diff --git a/PKGBUILD b/PKGBUILD index 95c5d29..da92cce 100644 --- a/PKGBUILD +++ b/PKGBUILD @@ -245,9 +245,9 @@ case $_basever in 0004-glitched-ondemand-muqss.patch 0004-glitched-muqss.patch 0004-5.9-ck1.patch - #0005-undead-glitched-ondemand-pds.patch - #0005-undead-glitched-pds.patch - #0005-v5.8_undead-pds099o.patch + 0005-undead-glitched-ondemand-pds.patch + 0005-undead-glitched-pds.patch + 0005-v5.9_undead-pds099o.patch 0005-glitched-pds.patch 0006-add-acs-overrides_iommu.patch 0007-v5.9-fsync.patch @@ -272,6 +272,9 @@ case $_basever in 'c605f638d74c61861ebdc36ebd4cb8b6475eae2f6273e1ccb2bbb3e10a2ec3fe' '2bbbac963b6ca44ef3f8a71ec7c5cad7d66df860869a73059087ee236775970a' '45a9ab99215ab3313be6e66e073d29154aac55bc58975a4df2dad116c918d27c' + '62496f9ca788996181ef145f96ad26291282fcc3fb95cdc04080dcf84365be33' + '31b428c464905e44ed61cdcd1f42b4ec157ebe5a44cb5b608c4c99b466df66ba' + 'f9f5f0a3a1d6c5233b9d7a4afe8ed99be97c4ff00a80bde4017d117c7d5f98ed' 'fca63d15ca4502aebd73e76d7499b243d2c03db71ff5ab0bf5cf268b2e576320' '19661ec0d39f9663452b34433214c755179894528bf73a42f6ba52ccf572832a' 'b302ba6c5bbe8ed19b20207505d513208fae1e678cf4d8e7ac0b154e5fe3f456' diff --git a/linux-tkg-config/prepare b/linux-tkg-config/prepare index eda9539..ad81728 100644 --- a/linux-tkg-config/prepare +++ b/linux-tkg-config/prepare @@ -127,7 +127,7 @@ _tkg_initscript() { plain "What CPU sched variant do you want to build/install?" if [ "$_basever" = "54" ] || [ "$_basever" = "57" ]; then prompt="`echo $' > 1.PDS\n 2.MuQSS\n 3.BMQ\n 4.CFS\nchoice[1-4?]: '`" - elif [ "$_basever" = "58" ]; then + elif [ "$_basever" = "58" ] || [ "$_basever" = "59" ]; then prompt="`echo $' > 1.Undead PDS (TkG)\n 2.Project C / PDS\n 3.Project C / BMQ\n 4.CFS\nchoice[1-4?]: '`" else prompt="`echo $' > 1.Project C / PDS\n 2.Project C / BMQ\n 3.MuQSS\n 4.CFS\nchoice[1-4?]: '`" @@ -150,7 +150,7 @@ _tkg_initscript() { elif [ "$CONDITION" = "4" ]; then echo "_cpusched=\"cfs\"" > "${_path}"/cpuschedset else - if [ "$_basever" = "58" ]; then + if [ "$_basever" = "58" ] || [ "$_basever" = "59" ]; then echo "_cpusched=\"upds\"" > "${_path}"/cpuschedset else echo "_cpusched=\"pds\"" > "${_path}"/cpuschedset @@ -382,8 +382,8 @@ _tkg_srcprep() { tkgpatch="$srcdir/0009-prjc_v${_basekernel}-r${rev}.patch" && _tkg_patcher fi - # 5.8 upds naming quirk - if [ "$_basever" = "58" ] && [ "${_cpusched}" = "upds" ];then + # upds naming quirk + if [ "${_cpusched}" = "upds" ];then # is it dead or alive doa="-undead" fi diff --git a/linux-tkg-patches/5.9/0005-undead-glitched-ondemand-pds.patch b/linux-tkg-patches/5.9/0005-undead-glitched-ondemand-pds.patch new file mode 100644 index 0000000..c1929e8 --- /dev/null +++ b/linux-tkg-patches/5.9/0005-undead-glitched-ondemand-pds.patch @@ -0,0 +1,18 @@ +diff --git a/drivers/cpufreq/cpufreq_ondemand.c b/drivers/cpufreq/cpufreq_ondemand.c +index 6b423eebfd5d..61e3271675d6 100644 +--- a/drivers/cpufreq/cpufreq_ondemand.c ++++ b/drivers/cpufreq/cpufreq_ondemand.c +@@ -21,10 +21,10 @@ + #include "cpufreq_ondemand.h" + + /* On-demand governor macros */ +-#define DEF_FREQUENCY_UP_THRESHOLD (63) +-#define DEF_SAMPLING_DOWN_FACTOR (1) ++#define DEF_FREQUENCY_UP_THRESHOLD (55) ++#define DEF_SAMPLING_DOWN_FACTOR (5) + #define MAX_SAMPLING_DOWN_FACTOR (100000) +-#define MICRO_FREQUENCY_UP_THRESHOLD (95) ++#define MICRO_FREQUENCY_UP_THRESHOLD (63) + #define MICRO_FREQUENCY_MIN_SAMPLE_RATE (10000) + #define MIN_FREQUENCY_UP_THRESHOLD (1) + #define MAX_FREQUENCY_UP_THRESHOLD (100) diff --git a/linux-tkg-patches/5.9/0005-undead-glitched-pds.patch b/linux-tkg-patches/5.9/0005-undead-glitched-pds.patch new file mode 100644 index 0000000..1e015a4 --- /dev/null +++ b/linux-tkg-patches/5.9/0005-undead-glitched-pds.patch @@ -0,0 +1,165 @@ +From f7f49141a5dbe9c99d78196b58c44307fb2e6be3 Mon Sep 17 00:00:00 2001 +From: Tk-Glitch +Date: Wed, 4 Jul 2018 04:30:08 +0200 +Subject: glitched - PDS + +diff --git a/kernel/Kconfig.hz b/kernel/Kconfig.hz +index 2a202a846757..1d9c7ed79b11 100644 +--- a/kernel/Kconfig.hz ++++ b/kernel/Kconfig.hz +@@ -4,7 +4,7 @@ + + choice + prompt "Timer frequency" +- default HZ_250 ++ default HZ_500 + help + Allows the configuration of the timer frequency. It is customary + to have the timer interrupt run at 1000 Hz but 100 Hz may be more +@@ -39,6 +39,13 @@ choice + on SMP and NUMA systems and exactly dividing by both PAL and + NTSC frame rates for video and multimedia work. + ++ config HZ_500 ++ bool "500 HZ" ++ help ++ 500 Hz is a balanced timer frequency. Provides fast interactivity ++ on desktops with great smoothness without increasing CPU power ++ consumption and sacrificing the battery life on laptops. ++ + config HZ_1000 + bool "1000 HZ" + help +@@ -52,6 +59,7 @@ config HZ + default 100 if HZ_100 + default 250 if HZ_250 + default 300 if HZ_300 ++ default 500 if HZ_500 + default 1000 if HZ_1000 + + config SCHED_HRTICK + +diff --git a/kernel/Kconfig.hz b/kernel/Kconfig.hz +index 2a202a846757..1d9c7ed79b11 100644 +--- a/kernel/Kconfig.hz ++++ b/kernel/Kconfig.hz +@@ -4,7 +4,7 @@ + + choice + prompt "Timer frequency" +- default HZ_500 ++ default HZ_750 + help + Allows the configuration of the timer frequency. It is customary + to have the timer interrupt run at 1000 Hz but 100 Hz may be more +@@ -46,6 +46,13 @@ choice + on desktops with great smoothness without increasing CPU power + consumption and sacrificing the battery life on laptops. + ++ config HZ_750 ++ bool "750 HZ" ++ help ++ 750 Hz is a good timer frequency for desktops. Provides fast ++ interactivity with great smoothness without sacrificing too ++ much throughput. ++ + config HZ_1000 + bool "1000 HZ" + help +@@ -60,6 +67,7 @@ config HZ + default 250 if HZ_250 + default 300 if HZ_300 + default 500 if HZ_500 ++ default 750 if HZ_750 + default 1000 if HZ_1000 + + config SCHED_HRTICK + +diff --git a/mm/vmscan.c b/mm/vmscan.c +index 9270a4370d54..30d01e647417 100644 +--- a/mm/vmscan.c ++++ b/mm/vmscan.c +@@ -169,7 +169,7 @@ + /* + * From 0 .. 200. Higher means more swappy. + */ +-int vm_swappiness = 60; ++int vm_swappiness = 20; + + static void set_task_reclaim_state(struct task_struct *task, + struct reclaim_state *rs) +diff --git a/init/Kconfig b/init/Kconfig +index 11fd9b502d06..e9bc34d3019b 100644 +--- a/init/Kconfig ++++ b/init/Kconfig +@@ -715,6 +715,7 @@ menu "Scheduler features" + config UCLAMP_TASK + bool "Enable utilization clamping for RT/FAIR tasks" + depends on CPU_FREQ_GOV_SCHEDUTIL ++ depends on !SCHED_PDS + help + This feature enables the scheduler to track the clamped utilization + of each CPU based on RUNNABLE tasks scheduled on that CPU. +@@ -948,7 +948,6 @@ config CGROUP_DEVICE + + config CGROUP_CPUACCT + bool "Simple CPU accounting controller" +- depends on !SCHED_PDS + help + Provides a simple controller for monitoring the + total CPU consumed by the tasks in a cgroup. +diff --git a/kernel/sched/Makefile b/kernel/sched/Makefile +index b23231bae996..cab4e5c5b38e 100644 +--- a/kernel/sched/Makefile ++++ b/kernel/sched/Makefile +@@ -24,13 +24,13 @@ obj-y += fair.o rt.o deadline.o + obj-$(CONFIG_SMP) += cpudeadline.o topology.o stop_task.o + obj-$(CONFIG_SCHED_AUTOGROUP) += autogroup.o + obj-$(CONFIG_SCHED_DEBUG) += debug.o +-obj-$(CONFIG_CGROUP_CPUACCT) += cpuacct.o + endif + obj-y += loadavg.o clock.o cputime.o + obj-y += idle.o + obj-y += wait.o wait_bit.o swait.o completion.o + obj-$(CONFIG_SMP) += cpupri.o pelt.o + obj-$(CONFIG_SCHEDSTATS) += stats.o ++obj-$(CONFIG_CGROUP_CPUACCT) += cpuacct.o + obj-$(CONFIG_CPU_FREQ) += cpufreq.o + obj-$(CONFIG_CPU_FREQ_GOV_SCHEDUTIL) += cpufreq_schedutil.o + obj-$(CONFIG_MEMBARRIER) += membarrier.o + +diff --git a/kernel/sched/pds.c b/kernel/sched/pds.c +index 9281ad164..f09a609cf 100644 +--- a/kernel/sched/pds.c ++++ b/kernel/sched/pds.c +@@ -81,6 +81,18 @@ enum { + NR_CPU_AFFINITY_CHK_LEVEL + }; + ++/* ++ * This allows printing both to /proc/sched_debug and ++ * to the console ++ */ ++#define SEQ_printf(m, x...) \ ++ do { \ ++ if (m) \ ++ seq_printf(m, x); \ ++ else \ ++ pr_cont(x); \ ++ } while (0) ++ + static inline void print_scheduler_version(void) + { + printk(KERN_INFO "pds: PDS-mq CPU Scheduler 0.99o by Alfred Chen.\n"); +@@ -6353,7 +6365,10 @@ void ia64_set_curr_task(int cpu, struct task_struct *p) + #ifdef CONFIG_SCHED_DEBUG + void proc_sched_show_task(struct task_struct *p, struct pid_namespace *ns, + struct seq_file *m) +-{} ++{ ++ SEQ_printf(m, "%s (%d, #threads: %d)\n", p->comm, task_pid_nr_ns(p, ns), ++ get_nr_threads(p)); ++} + + void proc_sched_set_task(struct task_struct *p) + {} diff --git a/linux-tkg-patches/5.9/0005-v5.9_undead-pds099o.patch b/linux-tkg-patches/5.9/0005-v5.9_undead-pds099o.patch new file mode 100644 index 0000000..69c84d7 --- /dev/null +++ b/linux-tkg-patches/5.9/0005-v5.9_undead-pds099o.patch @@ -0,0 +1,8715 @@ +From abe64ed9851070719c21d76f348f638d0803e2f9 Mon Sep 17 00:00:00 2001 +From: Tk-Glitch +Date: Thu, 29 Oct 2020 21:28:03 +0100 +Subject: PDS 099o, 5.9 rebase + + +diff --git a/Documentation/scheduler/sched-PDS-mq.txt b/Documentation/scheduler/sched-PDS-mq.txt +new file mode 100644 +index 000000000000..709e86f6487e +--- /dev/null ++++ b/Documentation/scheduler/sched-PDS-mq.txt +@@ -0,0 +1,56 @@ ++ Priority and Deadline based Skiplist multiple queue Scheduler ++ ------------------------------------------------------------- ++ ++CONTENT ++======== ++ ++ 0. Development ++ 1. Overview ++ 1.1 Design goal ++ 1.2 Design summary ++ 2. Design Detail ++ 2.1 Skip list implementation ++ 2.2 Task preempt ++ 2.3 Task policy, priority and deadline ++ 2.4 Task selection ++ 2.5 Run queue balance ++ 2.6 Task migration ++ ++ ++0. Development ++============== ++ ++Priority and Deadline based Skiplist multiple queue scheduler, referred to as ++PDS from here on, is developed upon the enhancement patchset VRQ(Variable Run ++Queue) for BFS(Brain Fuck Scheduler by Con Kolivas). PDS inherits the existing ++design from VRQ and inspired by the introduction of skiplist data structure ++to the scheduler by Con Kolivas. However, PDS is different from MuQSS(Multiple ++Queue Skiplist Scheduler, the successor after BFS) in many ways. ++ ++1. Overview ++=========== ++ ++1.1 Design goal ++--------------- ++ ++PDS is designed to make the cpu process scheduler code to be simple, but while ++efficiency and scalable. Be Simple, the scheduler code will be easy to be read ++and the behavious of scheduler will be easy to predict. Be efficiency, the ++scheduler shall be well balance the thoughput performance and task interactivity ++at the same time for different properties the tasks behave. Be scalable, the ++performance of the scheduler should be in good shape with the glowing of ++workload or with the growing of the cpu numbers. ++ ++1.2 Design summary ++------------------ ++ ++PDS is described as a multiple run queues cpu scheduler. Each cpu has its own ++run queue. A heavry customized skiplist is used as the backend data structure ++of the cpu run queue. Tasks in run queue is sorted by priority then virtual ++deadline(simplfy to just deadline from here on). In PDS, balance action among ++run queues are kept as less as possible to reduce the migration cost. Cpumask ++data structure is widely used in cpu affinity checking and cpu preemption/ ++selection to make PDS scalable with increasing cpu number. ++ ++ ++To be continued... +diff --git a/arch/powerpc/platforms/cell/spufs/sched.c b/arch/powerpc/platforms/cell/spufs/sched.c +index f18d5067cd0f..fe489fc01c73 100644 +--- a/arch/powerpc/platforms/cell/spufs/sched.c ++++ b/arch/powerpc/platforms/cell/spufs/sched.c +@@ -51,11 +51,6 @@ static struct task_struct *spusched_task; + static struct timer_list spusched_timer; + static struct timer_list spuloadavg_timer; + +-/* +- * Priority of a normal, non-rt, non-niced'd process (aka nice level 0). +- */ +-#define NORMAL_PRIO 120 +- + /* + * Frequency of the spu scheduler tick. By default we do one SPU scheduler + * tick for every 10 CPU scheduler ticks. +diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig +index 7101ac64bb20..1072a32fbca2 100644 +--- a/arch/x86/Kconfig ++++ b/arch/x86/Kconfig +@@ -1005,6 +1005,22 @@ config NR_CPUS + config SCHED_SMT + def_bool y if SMP + ++config SMT_NICE ++ bool "SMT (Hyperthreading) aware nice priority and policy support" ++ depends on SCHED_PDS && SCHED_SMT ++ default y ++ help ++ Enabling Hyperthreading on Intel CPUs decreases the effectiveness ++ of the use of 'nice' levels and different scheduling policies ++ (e.g. realtime) due to sharing of CPU power between hyperthreads. ++ SMT nice support makes each logical CPU aware of what is running on ++ its hyperthread siblings, maintaining appropriate distribution of ++ CPU according to nice levels and scheduling policies at the expense ++ of slightly increased overhead. ++ ++ If unsure say Y here. ++ ++ + config SCHED_MC + def_bool y + prompt "Multi-core scheduler support" +diff --git a/drivers/cpufreq/cpufreq_conservative.c b/drivers/cpufreq/cpufreq_conservative.c +index aa39ff31ec9f..eb72535ba99a 100644 +--- a/drivers/cpufreq/cpufreq_conservative.c ++++ b/drivers/cpufreq/cpufreq_conservative.c +@@ -28,8 +28,8 @@ struct cs_dbs_tuners { + }; + + /* Conservative governor macros */ +-#define DEF_FREQUENCY_UP_THRESHOLD (80) +-#define DEF_FREQUENCY_DOWN_THRESHOLD (20) ++#define DEF_FREQUENCY_UP_THRESHOLD (63) ++#define DEF_FREQUENCY_DOWN_THRESHOLD (26) + #define DEF_FREQUENCY_STEP (5) + #define DEF_SAMPLING_DOWN_FACTOR (1) + #define MAX_SAMPLING_DOWN_FACTOR (10) +diff --git a/drivers/cpufreq/cpufreq_ondemand.c b/drivers/cpufreq/cpufreq_ondemand.c +index ac361a8b1d3b..cbf7ed716f20 100644 +--- a/drivers/cpufreq/cpufreq_ondemand.c ++++ b/drivers/cpufreq/cpufreq_ondemand.c +@@ -18,7 +18,7 @@ + #include "cpufreq_ondemand.h" + + /* On-demand governor macros */ +-#define DEF_FREQUENCY_UP_THRESHOLD (80) ++#define DEF_FREQUENCY_UP_THRESHOLD (63) + #define DEF_SAMPLING_DOWN_FACTOR (1) + #define MAX_SAMPLING_DOWN_FACTOR (100000) + #define MICRO_FREQUENCY_UP_THRESHOLD (95) +@@ -127,7 +127,7 @@ static void dbs_freq_increase(struct cpufreq_policy *policy, unsigned int freq) + } + + /* +- * Every sampling_rate, we check, if current idle time is less than 20% ++ * Every sampling_rate, we check, if current idle time is less than 37% + * (default), then we try to increase frequency. Else, we adjust the frequency + * proportional to load. + */ +diff --git a/fs/proc/base.c b/fs/proc/base.c +index 617db4e0faa0..f85926764f9a 100644 +--- a/fs/proc/base.c ++++ b/fs/proc/base.c +@@ -479,7 +479,7 @@ static int proc_pid_schedstat(struct seq_file *m, struct pid_namespace *ns, + seq_puts(m, "0 0 0\n"); + else + seq_printf(m, "%llu %llu %lu\n", +- (unsigned long long)task->se.sum_exec_runtime, ++ (unsigned long long)tsk_seruntime(task), + (unsigned long long)task->sched_info.run_delay, + task->sched_info.pcount); + +diff --git a/include/linux/init_task.h b/include/linux/init_task.h +index 2c620d7ac432..1a7987c40c80 100644 +--- a/include/linux/init_task.h ++++ b/include/linux/init_task.h +@@ -36,7 +36,11 @@ extern struct cred init_cred; + #define INIT_PREV_CPUTIME(x) + #endif + ++#ifdef CONFIG_SCHED_PDS ++#define INIT_TASK_COMM "PDS" ++#else + #define INIT_TASK_COMM "swapper" ++#endif /* !CONFIG_SCHED_PDS */ + + /* Attach to the init_task data structure for proper alignment */ + #ifdef CONFIG_ARCH_TASK_STRUCT_ON_STACK +diff --git a/include/linux/jiffies.h b/include/linux/jiffies.h +index fed6ba96c527..f03a5ee419a1 100644 +--- a/include/linux/jiffies.h ++++ b/include/linux/jiffies.h +@@ -169,7 +169,7 @@ static inline u64 get_jiffies_64(void) + * Have the 32 bit jiffies value wrap 5 minutes after boot + * so jiffies wrap bugs show up earlier. + */ +-#define INITIAL_JIFFIES ((unsigned long)(unsigned int) (-300*HZ)) ++#define INITIAL_JIFFIES ((unsigned long)(unsigned int) (-10*HZ)) + + /* + * Change timeval to jiffies, trying to avoid the +diff --git a/include/linux/sched.h b/include/linux/sched.h +index afe01e232935..192c955964d3 100644 +--- a/include/linux/sched.h ++++ b/include/linux/sched.h +@@ -34,6 +34,7 @@ + #include + #include + #include ++#include + + /* task_struct member predeclarations (sorted alphabetically): */ + struct audit_context; +@@ -651,9 +652,13 @@ struct task_struct { + unsigned int flags; + unsigned int ptrace; + +-#ifdef CONFIG_SMP ++#if defined(CONFIG_SMP) || defined(CONFIG_SCHED_PDS) + int on_cpu; ++#endif ++#if defined(CONFIG_SMP) && !defined(CONFIG_SCHED_PDS) + struct __call_single_node wake_entry; ++#endif ++#ifdef CONFIG_SMP + #ifdef CONFIG_THREAD_INFO_IN_TASK + /* Current CPU: */ + unsigned int cpu; +@@ -662,6 +667,7 @@ struct task_struct { + unsigned long wakee_flip_decay_ts; + struct task_struct *last_wakee; + ++#ifndef CONFIG_SCHED_PDS + /* + * recent_used_cpu is initially set as the last CPU used by a task + * that wakes affine another task. Waker/wakee relationships can +@@ -670,6 +676,7 @@ struct task_struct { + * used CPU that may be idle. + */ + int recent_used_cpu; ++#endif /* CONFIG_SCHED_PDS */ + int wake_cpu; + #endif + int on_rq; +@@ -679,13 +686,27 @@ struct task_struct { + int normal_prio; + unsigned int rt_priority; + ++#ifdef CONFIG_SCHED_PDS ++ int time_slice; ++ u64 deadline; ++ /* skip list level */ ++ int sl_level; ++ /* skip list node */ ++ struct skiplist_node sl_node; ++ /* 8bits prio and 56bits deadline for quick processing */ ++ u64 priodl; ++ u64 last_ran; ++ /* sched_clock time spent running */ ++ u64 sched_time; ++#else /* CONFIG_SCHED_PDS */ + const struct sched_class *sched_class; + struct sched_entity se; + struct sched_rt_entity rt; ++ struct sched_dl_entity dl; ++#endif + #ifdef CONFIG_CGROUP_SCHED + struct task_group *sched_task_group; + #endif +- struct sched_dl_entity dl; + + #ifdef CONFIG_UCLAMP_TASK + /* +@@ -1332,6 +1353,29 @@ struct task_struct { + */ + }; + ++#ifdef CONFIG_SCHED_PDS ++void cpu_scaling(int cpu); ++void cpu_nonscaling(int cpu); ++#define tsk_seruntime(t) ((t)->sched_time) ++/* replace the uncertian rt_timeout with 0UL */ ++#define tsk_rttimeout(t) (0UL) ++ ++#define task_running_idle(p) ((p)->prio == IDLE_PRIO) ++#else /* CFS */ ++extern int runqueue_is_locked(int cpu); ++static inline void cpu_scaling(int cpu) ++{ ++} ++ ++static inline void cpu_nonscaling(int cpu) ++{ ++} ++#define tsk_seruntime(t) ((t)->se.sum_exec_runtime) ++#define tsk_rttimeout(t) ((t)->rt.timeout) ++ ++#define iso_task(p) (false) ++#endif /* CONFIG_SCHED_PDS */ ++ + static inline struct pid *task_pid(struct task_struct *task) + { + return task->thread_pid; +diff --git a/include/linux/sched/deadline.h b/include/linux/sched/deadline.h +index 1aff00b65f3c..a5e5fc2c9170 100644 +--- a/include/linux/sched/deadline.h ++++ b/include/linux/sched/deadline.h +@@ -1,5 +1,22 @@ + /* SPDX-License-Identifier: GPL-2.0 */ + ++#ifdef CONFIG_SCHED_PDS ++ ++#define __tsk_deadline(p) ((p)->deadline) ++ ++static inline int dl_prio(int prio) ++{ ++ return 1; ++} ++ ++static inline int dl_task(struct task_struct *p) ++{ ++ return 1; ++} ++#else ++ ++#define __tsk_deadline(p) ((p)->dl.deadline) ++ + /* + * SCHED_DEADLINE tasks has negative priorities, reflecting + * the fact that any of them has higher prio than RT and +@@ -19,6 +36,7 @@ static inline int dl_task(struct task_struct *p) + { + return dl_prio(p->prio); + } ++#endif /* CONFIG_SCHED_PDS */ + + static inline bool dl_time_before(u64 a, u64 b) + { +diff --git a/include/linux/sched/prio.h b/include/linux/sched/prio.h +index 7d64feafc408..fba04bb91492 100644 +--- a/include/linux/sched/prio.h ++++ b/include/linux/sched/prio.h +@@ -20,7 +20,18 @@ + */ + + #define MAX_USER_RT_PRIO 100 ++ ++#ifdef CONFIG_SCHED_PDS ++#define ISO_PRIO (MAX_USER_RT_PRIO) ++ ++#define MAX_RT_PRIO ((MAX_USER_RT_PRIO) + 1) ++ ++#define NORMAL_PRIO (MAX_RT_PRIO) ++#define IDLE_PRIO ((MAX_RT_PRIO) + 1) ++#define PRIO_LIMIT ((IDLE_PRIO) + 1) ++#else /* !CONFIG_SCHED_PDS */ + #define MAX_RT_PRIO MAX_USER_RT_PRIO ++#endif /* CONFIG_SCHED_PDS */ + + #define MAX_PRIO (MAX_RT_PRIO + NICE_WIDTH) + #define DEFAULT_PRIO (MAX_RT_PRIO + NICE_WIDTH / 2) +diff --git a/include/linux/sched/rt.h b/include/linux/sched/rt.h +index e5af028c08b4..a96012e6f15e 100644 +--- a/include/linux/sched/rt.h ++++ b/include/linux/sched/rt.h +@@ -24,8 +24,10 @@ static inline bool task_is_realtime(struct task_struct *tsk) + + if (policy == SCHED_FIFO || policy == SCHED_RR) + return true; ++#ifndef CONFIG_SCHED_PDS + if (policy == SCHED_DEADLINE) + return true; ++#endif + return false; + } + +diff --git a/include/linux/sched/task.h b/include/linux/sched/task.h +index a98965007eef..c68b76cc01dc 100644 +--- a/include/linux/sched/task.h ++++ b/include/linux/sched/task.h +@@ -93,7 +93,7 @@ int kernel_wait(pid_t pid, int *stat); + extern void free_task(struct task_struct *tsk); + + /* sched_exec is called by processes performing an exec */ +-#ifdef CONFIG_SMP ++#if defined(CONFIG_SMP) && !defined(CONFIG_SCHED_PDS) + extern void sched_exec(void); + #else + #define sched_exec() {} +diff --git a/include/linux/skip_list.h b/include/linux/skip_list.h +new file mode 100644 +index 000000000000..713fedd8034f +--- /dev/null ++++ b/include/linux/skip_list.h +@@ -0,0 +1,177 @@ ++/* ++ Copyright (C) 2016 Alfred Chen. ++ ++ Code based on Con Kolivas's skip list implementation for BFS, and ++ which is based on example originally by William Pugh. ++ ++Skip Lists are a probabilistic alternative to balanced trees, as ++described in the June 1990 issue of CACM and were invented by ++William Pugh in 1987. ++ ++A couple of comments about this implementation: ++ ++This file only provides a infrastructure of skip list. ++ ++skiplist_node is embedded into container data structure, to get rid the ++dependency of kmalloc/kfree operation in scheduler code. ++ ++A customized search function should be defined using DEFINE_SKIPLIST_INSERT ++macro and be used for skip list insert operation. ++ ++Random Level is also not defined in this file, instead, it should be customized ++implemented and set to node->level then pass to the customized skiplist_insert ++function. ++ ++Levels start at zero and go up to (NUM_SKIPLIST_LEVEL -1) ++ ++NUM_SKIPLIST_LEVEL in this implementation is 8 instead of origin 16, ++considering that there will be 256 entries to enable the top level when using ++random level p=0.5, and that number is more than enough for a run queue usage ++in a scheduler usage. And it also help to reduce the memory usage of the ++embedded skip list node in task_struct to about 50%. ++ ++The insertion routine has been implemented so as to use the ++dirty hack described in the CACM paper: if a random level is ++generated that is more than the current maximum level, the ++current maximum level plus one is used instead. ++ ++BFS Notes: In this implementation of skiplists, there are bidirectional ++next/prev pointers and the insert function returns a pointer to the actual ++node the value is stored. The key here is chosen by the scheduler so as to ++sort tasks according to the priority list requirements and is no longer used ++by the scheduler after insertion. The scheduler lookup, however, occurs in ++O(1) time because it is always the first item in the level 0 linked list. ++Since the task struct stores a copy of the node pointer upon skiplist_insert, ++it can also remove it much faster than the original implementation with the ++aid of prev<->next pointer manipulation and no searching. ++*/ ++#ifndef _LINUX_SKIP_LIST_H ++#define _LINUX_SKIP_LIST_H ++ ++#include ++ ++#define NUM_SKIPLIST_LEVEL (8) ++ ++struct skiplist_node { ++ int level; /* Levels in this node */ ++ struct skiplist_node *next[NUM_SKIPLIST_LEVEL]; ++ struct skiplist_node *prev[NUM_SKIPLIST_LEVEL]; ++}; ++ ++#define SKIPLIST_NODE_INIT(name) { 0,\ ++ {&name, &name, &name, &name,\ ++ &name, &name, &name, &name},\ ++ {&name, &name, &name, &name,\ ++ &name, &name, &name, &name},\ ++ } ++ ++static inline void INIT_SKIPLIST_NODE(struct skiplist_node *node) ++{ ++ /* only level 0 ->next matters in skiplist_empty()*/ ++ WRITE_ONCE(node->next[0], node); ++} ++ ++/** ++ * FULL_INIT_SKIPLIST_NODE -- fully init a skiplist_node, expecially for header ++ * @node: the skip list node to be inited. ++ */ ++static inline void FULL_INIT_SKIPLIST_NODE(struct skiplist_node *node) ++{ ++ int i; ++ ++ node->level = 0; ++ for (i = 0; i < NUM_SKIPLIST_LEVEL; i++) { ++ WRITE_ONCE(node->next[i], node); ++ node->prev[i] = node; ++ } ++} ++ ++/** ++ * skiplist_empty - test whether a skip list is empty ++ * @head: the skip list to test. ++ */ ++static inline int skiplist_empty(const struct skiplist_node *head) ++{ ++ return READ_ONCE(head->next[0]) == head; ++} ++ ++/** ++ * skiplist_entry - get the struct for this entry ++ * @ptr: the &struct skiplist_node pointer. ++ * @type: the type of the struct this is embedded in. ++ * @member: the name of the skiplist_node within the struct. ++ */ ++#define skiplist_entry(ptr, type, member) \ ++ container_of(ptr, type, member) ++ ++/** ++ * DEFINE_SKIPLIST_INSERT_FUNC -- macro to define a customized skip list insert ++ * function, which takes two parameters, first one is the header node of the ++ * skip list, second one is the skip list node to be inserted ++ * @func_name: the customized skip list insert function name ++ * @search_func: the search function to be used, which takes two parameters, ++ * 1st one is the itrator of skiplist_node in the list, the 2nd is the skip list ++ * node to be inserted, the function should return true if search should be ++ * continued, otherwise return false. ++ * Returns 1 if @node is inserted as the first item of skip list at level zero, ++ * otherwise 0 ++ */ ++#define DEFINE_SKIPLIST_INSERT_FUNC(func_name, search_func)\ ++static inline int func_name(struct skiplist_node *head, struct skiplist_node *node)\ ++{\ ++ struct skiplist_node *update[NUM_SKIPLIST_LEVEL];\ ++ struct skiplist_node *p, *q;\ ++ int k = head->level;\ ++\ ++ p = head;\ ++ do {\ ++ while (q = p->next[k], q != head && search_func(q, node))\ ++ p = q;\ ++ update[k] = p;\ ++ } while (--k >= 0);\ ++\ ++ k = node->level;\ ++ if (unlikely(k > head->level)) {\ ++ node->level = k = ++head->level;\ ++ update[k] = head;\ ++ }\ ++\ ++ do {\ ++ p = update[k];\ ++ q = p->next[k];\ ++ node->next[k] = q;\ ++ p->next[k] = node;\ ++ node->prev[k] = p;\ ++ q->prev[k] = node;\ ++ } while (--k >= 0);\ ++\ ++ return (p == head);\ ++} ++ ++/** ++ * skiplist_del_init -- delete skip list node from a skip list and reset it's ++ * init state ++ * @head: the header node of the skip list to be deleted from. ++ * @node: the skip list node to be deleted, the caller need to ensure @node is ++ * in skip list which @head represent. ++ * Returns 1 if @node is the first item of skip level at level zero, otherwise 0 ++ */ ++static inline int ++skiplist_del_init(struct skiplist_node *head, struct skiplist_node *node) ++{ ++ int l, m = node->level; ++ ++ for (l = 0; l <= m; l++) { ++ node->prev[l]->next[l] = node->next[l]; ++ node->next[l]->prev[l] = node->prev[l]; ++ } ++ if (m == head->level && m > 0) { ++ while (head->next[m] == head && m > 0) ++ m--; ++ head->level = m; ++ } ++ INIT_SKIPLIST_NODE(node); ++ ++ return (node->prev[0] == head); ++} ++#endif /* _LINUX_SKIP_LIST_H */ +diff --git a/include/uapi/linux/sched.h b/include/uapi/linux/sched.h +index 3bac0a8ceab2..f692642cf2da 100644 +--- a/include/uapi/linux/sched.h ++++ b/include/uapi/linux/sched.h +@@ -115,7 +115,10 @@ struct clone_args { + #define SCHED_FIFO 1 + #define SCHED_RR 2 + #define SCHED_BATCH 3 +-/* SCHED_ISO: reserved but not implemented yet */ ++/* SCHED_ISO: Implemented in BFS/MuQSSPDS only */ ++ ++#define SCHED_ISO 4 ++ + #define SCHED_IDLE 5 + #define SCHED_DEADLINE 6 + +diff --git a/init/Kconfig b/init/Kconfig +index d6a0b31b13dc..d4fcda3add24 100644 +--- a/init/Kconfig ++++ b/init/Kconfig +@@ -92,6 +92,21 @@ config THREAD_INFO_IN_TASK + + menu "General setup" + ++config SCHED_PDS ++ bool "PDS-mq cpu scheduler" ++ help ++ The Priority and Deadline based Skip list multiple queue CPU ++ Scheduler for excellent interactivity and responsiveness on the ++ desktop and solid scalability on normal hardware and commodity ++ servers. ++ ++ Currently incompatible with the Group CPU scheduler, and RCU TORTURE ++ TEST so these options are disabled. ++ ++ Say Y here. ++ default y ++ ++ + config BROKEN + bool + +@@ -858,6 +873,7 @@ config NUMA_BALANCING + depends on ARCH_SUPPORTS_NUMA_BALANCING + depends on !ARCH_WANT_NUMA_VARIABLE_LOCALITY + depends on SMP && NUMA && MIGRATION ++ depends on !SCHED_PDS + help + This option adds support for automatic NUMA aware memory/task placement. + The mechanism is quite primitive and is based on migrating memory when +@@ -944,7 +960,7 @@ menuconfig CGROUP_SCHED + bandwidth allocation to such task groups. It uses cgroups to group + tasks. + +-if CGROUP_SCHED ++if CGROUP_SCHED && !SCHED_PDS + config FAIR_GROUP_SCHED + bool "Group scheduling for SCHED_OTHER" + depends on CGROUP_SCHED +@@ -1073,6 +1089,7 @@ config CGROUP_DEVICE + + config CGROUP_CPUACCT + bool "Simple CPU accounting controller" ++ depends on !SCHED_PDS + help + Provides a simple controller for monitoring the + total CPU consumed by the tasks in a cgroup. +@@ -1200,6 +1217,7 @@ config CHECKPOINT_RESTORE + + config SCHED_AUTOGROUP + bool "Automatic process group scheduling" ++ depends on !SCHED_PDS + select CGROUPS + select CGROUP_SCHED + select FAIR_GROUP_SCHED +diff --git a/init/init_task.c b/init/init_task.c +index f6889fce64af..519552456bb5 100644 +--- a/init/init_task.c ++++ b/init/init_task.c +@@ -67,6 +67,127 @@ struct task_struct init_task + #endif + __aligned(L1_CACHE_BYTES) + = { ++#ifdef CONFIG_SCHED_PDS ++#ifdef CONFIG_THREAD_INFO_IN_TASK ++ .thread_info = INIT_THREAD_INFO(init_task), ++ .stack_refcount = ATOMIC_INIT(1), ++#endif ++ .state = 0, ++ .stack = init_stack, ++ .usage = ATOMIC_INIT(2), ++ .flags = PF_KTHREAD, ++ .prio = NORMAL_PRIO, ++ .static_prio = MAX_PRIO - 20, ++ .normal_prio = NORMAL_PRIO, ++ .deadline = 0, /* PDS only */ ++ .policy = SCHED_NORMAL, ++ .cpus_ptr = &init_task.cpus_mask, ++ .cpus_mask = CPU_MASK_ALL, ++ .nr_cpus_allowed= NR_CPUS, ++ .mm = NULL, ++ .active_mm = &init_mm, ++ .restart_block = { ++ .fn = do_no_restart_syscall, ++ }, ++ .sl_level = 0, /* PDS only */ ++ .sl_node = SKIPLIST_NODE_INIT(init_task.sl_node), /* PDS only */ ++ .time_slice = HZ, /* PDS only */ ++ .tasks = LIST_HEAD_INIT(init_task.tasks), ++#ifdef CONFIG_SMP ++ .pushable_tasks = PLIST_NODE_INIT(init_task.pushable_tasks, MAX_PRIO), ++#endif ++#ifdef CONFIG_CGROUP_SCHED ++ .sched_task_group = &root_task_group, ++#endif ++ .ptraced = LIST_HEAD_INIT(init_task.ptraced), ++ .ptrace_entry = LIST_HEAD_INIT(init_task.ptrace_entry), ++ .real_parent = &init_task, ++ .parent = &init_task, ++ .children = LIST_HEAD_INIT(init_task.children), ++ .sibling = LIST_HEAD_INIT(init_task.sibling), ++ .group_leader = &init_task, ++ RCU_POINTER_INITIALIZER(real_cred, &init_cred), ++ RCU_POINTER_INITIALIZER(cred, &init_cred), ++ .comm = INIT_TASK_COMM, ++ .thread = INIT_THREAD, ++ .fs = &init_fs, ++ .files = &init_files, ++ .signal = &init_signals, ++ .sighand = &init_sighand, ++ .nsproxy = &init_nsproxy, ++ .pending = { ++ .list = LIST_HEAD_INIT(init_task.pending.list), ++ .signal = {{0}} ++ }, ++ .blocked = {{0}}, ++ .alloc_lock = __SPIN_LOCK_UNLOCKED(init_task.alloc_lock), ++ .journal_info = NULL, ++ INIT_CPU_TIMERS(init_task) ++ .pi_lock = __RAW_SPIN_LOCK_UNLOCKED(init_task.pi_lock), ++ .timer_slack_ns = 50000, /* 50 usec default slack */ ++ .thread_pid = &init_struct_pid, ++ .thread_group = LIST_HEAD_INIT(init_task.thread_group), ++ .thread_node = LIST_HEAD_INIT(init_signals.thread_head), ++#ifdef CONFIG_AUDITSYSCALL ++ .loginuid = INVALID_UID, ++ .sessionid = AUDIT_SID_UNSET, ++#endif ++#ifdef CONFIG_PERF_EVENTS ++ .perf_event_mutex = __MUTEX_INITIALIZER(init_task.perf_event_mutex), ++ .perf_event_list = LIST_HEAD_INIT(init_task.perf_event_list), ++#endif ++#ifdef CONFIG_PREEMPT_RCU ++ .rcu_read_lock_nesting = 0, ++ .rcu_read_unlock_special.s = 0, ++ .rcu_node_entry = LIST_HEAD_INIT(init_task.rcu_node_entry), ++ .rcu_blocked_node = NULL, ++#endif ++#ifdef CONFIG_TASKS_RCU ++ .rcu_tasks_holdout = false, ++ .rcu_tasks_holdout_list = LIST_HEAD_INIT(init_task.rcu_tasks_holdout_list), ++ .rcu_tasks_idle_cpu = -1, ++#endif ++#ifdef CONFIG_CPUSETS ++ .mems_allowed_seq = SEQCNT_SPINLOCK_ZERO(init_task.mems_allowed_seq, ++ &init_task.alloc_lock), ++#endif ++#ifdef CONFIG_RT_MUTEXES ++ .pi_waiters = RB_ROOT_CACHED, ++ .pi_top_task = NULL, ++#endif ++ INIT_PREV_CPUTIME(init_task) ++#ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN ++ .vtime.seqcount = SEQCNT_ZERO(init_task.vtime_seqcount), ++ .vtime.starttime = 0, ++ .vtime.state = VTIME_SYS, ++#endif ++#ifdef CONFIG_NUMA_BALANCING ++ .numa_preferred_nid = -1, ++ .numa_group = NULL, ++ .numa_faults = NULL, ++#endif ++#ifdef CONFIG_KASAN ++ .kasan_depth = 1, ++#endif ++#ifdef CONFIG_TRACE_IRQFLAGS ++ .softirqs_enabled = 1, ++#endif ++#ifdef CONFIG_LOCKDEP ++ .lockdep_recursion = 0, ++#endif ++#ifdef CONFIG_FUNCTION_GRAPH_TRACER ++ .ret_stack = NULL, ++#endif ++#if defined(CONFIG_TRACING) && defined(CONFIG_PREEMPT) ++ .trace_recursion = 0, ++#endif ++#ifdef CONFIG_LIVEPATCH ++ .patch_state = KLP_UNDEFINED, ++#endif ++#ifdef CONFIG_SECURITY ++ .security = NULL, ++#endif ++#else /* CONFIG_SCHED_PDS */ + #ifdef CONFIG_THREAD_INFO_IN_TASK + .thread_info = INIT_THREAD_INFO(init_task), + .stack_refcount = REFCOUNT_INIT(1), +@@ -209,6 +329,7 @@ struct task_struct init_task + #ifdef CONFIG_SECCOMP + .seccomp = { .filter_count = ATOMIC_INIT(0) }, + #endif ++#endif /* CONFIG_SCHED_PDS */ + }; + EXPORT_SYMBOL(init_task); + +diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c +index 642415b8c3c9..952fe6cf948d 100644 +--- a/kernel/cgroup/cpuset.c ++++ b/kernel/cgroup/cpuset.c +@@ -636,7 +636,7 @@ static int validate_change(struct cpuset *cur, struct cpuset *trial) + return ret; + } + +-#ifdef CONFIG_SMP ++#if defined(CONFIG_SMP) && !defined(CONFIG_SCHED_PDS) + /* + * Helper routine for generate_sched_domains(). + * Do cpusets a, b have overlapping effective cpus_allowed masks? +@@ -1009,7 +1009,7 @@ static void rebuild_sched_domains_locked(void) + /* Have scheduler rebuild the domains */ + partition_and_rebuild_sched_domains(ndoms, doms, attr); + } +-#else /* !CONFIG_SMP */ ++#else /* !CONFIG_SMP || CONFIG_SCHED_PDS */ + static void rebuild_sched_domains_locked(void) + { + } +diff --git a/kernel/delayacct.c b/kernel/delayacct.c +index 27725754ac99..769d773c7182 100644 +--- a/kernel/delayacct.c ++++ b/kernel/delayacct.c +@@ -106,7 +106,7 @@ int __delayacct_add_tsk(struct taskstats *d, struct task_struct *tsk) + */ + t1 = tsk->sched_info.pcount; + t2 = tsk->sched_info.run_delay; +- t3 = tsk->se.sum_exec_runtime; ++ t3 = tsk_seruntime(tsk); + + d->cpu_count += t1; + +diff --git a/kernel/exit.c b/kernel/exit.c +index 733e80f334e7..3f3506c851fd 100644 +--- a/kernel/exit.c ++++ b/kernel/exit.c +@@ -121,7 +121,7 @@ static void __exit_signal(struct task_struct *tsk) + sig->curr_target = next_thread(tsk); + } + +- add_device_randomness((const void*) &tsk->se.sum_exec_runtime, ++ add_device_randomness((const void*) &tsk_seruntime(tsk), + sizeof(unsigned long long)); + + /* +@@ -142,7 +142,7 @@ static void __exit_signal(struct task_struct *tsk) + sig->inblock += task_io_get_inblock(tsk); + sig->oublock += task_io_get_oublock(tsk); + task_io_accounting_add(&sig->ioac, &tsk->ioac); +- sig->sum_sched_runtime += tsk->se.sum_exec_runtime; ++ sig->sum_sched_runtime += tsk_seruntime(tsk); + sig->nr_threads--; + __unhash_process(tsk, group_dead); + write_sequnlock(&sig->stats_lock); +diff --git a/kernel/livepatch/transition.c b/kernel/livepatch/transition.c +index f6310f848f34..b5de980c7d4e 100644 +--- a/kernel/livepatch/transition.c ++++ b/kernel/livepatch/transition.c +@@ -306,7 +306,11 @@ static bool klp_try_switch_task(struct task_struct *task) + */ + rq = task_rq_lock(task, &flags); + ++#ifdef CONFIG_SCHED_PDS ++ if (task_running(task) && task != current) { ++#else + if (task_running(rq, task) && task != current) { ++#endif + snprintf(err_buf, STACK_ERR_BUF_SIZE, + "%s: %s:%d is running\n", __func__, task->comm, + task->pid); +diff --git a/kernel/locking/rtmutex.c b/kernel/locking/rtmutex.c +index cfdd5b93264d..7577266d1c0c 100644 +--- a/kernel/locking/rtmutex.c ++++ b/kernel/locking/rtmutex.c +@@ -227,7 +227,7 @@ static inline bool unlock_rt_mutex_safe(struct rt_mutex *lock, + * Only use with rt_mutex_waiter_{less,equal}() + */ + #define task_to_waiter(p) \ +- &(struct rt_mutex_waiter){ .prio = (p)->prio, .deadline = (p)->dl.deadline } ++ &(struct rt_mutex_waiter){ .prio = (p)->prio, .deadline = __tsk_deadline(p) } + + static inline int + rt_mutex_waiter_less(struct rt_mutex_waiter *left, +@@ -678,7 +678,7 @@ static int rt_mutex_adjust_prio_chain(struct task_struct *task, + * the values of the node being removed. + */ + waiter->prio = task->prio; +- waiter->deadline = task->dl.deadline; ++ waiter->deadline = __tsk_deadline(task); + + rt_mutex_enqueue(lock, waiter); + +@@ -951,7 +951,7 @@ static int task_blocks_on_rt_mutex(struct rt_mutex *lock, + waiter->task = task; + waiter->lock = lock; + waiter->prio = task->prio; +- waiter->deadline = task->dl.deadline; ++ waiter->deadline = __tsk_deadline(task); + + /* Get the top priority waiter on the lock */ + if (rt_mutex_has_waiters(lock)) +diff --git a/kernel/sched/Makefile b/kernel/sched/Makefile +index 5fc9c9b70862..1b5bc273ec4b 100644 +--- a/kernel/sched/Makefile ++++ b/kernel/sched/Makefile +@@ -22,15 +22,21 @@ ifneq ($(CONFIG_SCHED_OMIT_FRAME_POINTER),y) + CFLAGS_core.o := $(PROFILING) -fno-omit-frame-pointer + endif + +-obj-y += core.o loadavg.o clock.o cputime.o +-obj-y += idle.o fair.o rt.o deadline.o +-obj-y += wait.o wait_bit.o swait.o completion.o +- +-obj-$(CONFIG_SMP) += cpupri.o cpudeadline.o topology.o stop_task.o pelt.o ++ifdef CONFIG_SCHED_PDS ++obj-y += pds.o ++else ++obj-y += core.o ++obj-y += fair.o rt.o deadline.o ++obj-$(CONFIG_SMP) += cpudeadline.o topology.o stop_task.o + obj-$(CONFIG_SCHED_AUTOGROUP) += autogroup.o +-obj-$(CONFIG_SCHEDSTATS) += stats.o + obj-$(CONFIG_SCHED_DEBUG) += debug.o + obj-$(CONFIG_CGROUP_CPUACCT) += cpuacct.o ++endif ++obj-y += loadavg.o clock.o cputime.o ++obj-y += idle.o ++obj-y += wait.o wait_bit.o swait.o completion.o ++obj-$(CONFIG_SMP) += cpupri.o pelt.o ++obj-$(CONFIG_SCHEDSTATS) += stats.o + obj-$(CONFIG_CPU_FREQ) += cpufreq.o + obj-$(CONFIG_CPU_FREQ_GOV_SCHEDUTIL) += cpufreq_schedutil.o + obj-$(CONFIG_MEMBARRIER) += membarrier.o +diff --git a/kernel/sched/cpufreq_schedutil.c b/kernel/sched/cpufreq_schedutil.c +index e39008242cf4..815be262eb90 100644 +--- a/kernel/sched/cpufreq_schedutil.c ++++ b/kernel/sched/cpufreq_schedutil.c +@@ -183,6 +183,7 @@ static unsigned int get_next_freq(struct sugov_policy *sg_policy, + return cpufreq_driver_resolve_freq(policy, freq); + } + ++#ifndef CONFIG_SCHED_PDS + /* + * This function computes an effective utilization for the given CPU, to be + * used for frequency selection given the linear relation: f = u * f_max. +@@ -300,6 +301,13 @@ static unsigned long sugov_get_util(struct sugov_cpu *sg_cpu) + + return schedutil_cpu_util(sg_cpu->cpu, util, max, FREQUENCY_UTIL, NULL); + } ++#else /* CONFIG_SCHED_PDS */ ++static unsigned long sugov_get_util(struct sugov_cpu *sg_cpu) ++{ ++ sg_cpu->max = arch_scale_cpu_capacity(sg_cpu->cpu); ++ return sg_cpu->max; ++} ++#endif + + /** + * sugov_iowait_reset() - Reset the IO boost status of a CPU. +@@ -443,7 +451,9 @@ static inline bool sugov_cpu_is_busy(struct sugov_cpu *sg_cpu) { return false; } + */ + static inline void ignore_dl_rate_limit(struct sugov_cpu *sg_cpu, struct sugov_policy *sg_policy) + { ++#ifndef CONFIG_SCHED_PDS + if (cpu_bw_dl(cpu_rq(sg_cpu->cpu)) > sg_cpu->bw_dl) ++#endif + sg_policy->limits_changed = true; + } + +@@ -686,6 +696,7 @@ static int sugov_kthread_create(struct sugov_policy *sg_policy) + } + + ret = sched_setattr_nocheck(thread, &attr); ++ + if (ret) { + kthread_stop(thread); + pr_warn("%s: failed to set SCHED_DEADLINE\n", __func__); +@@ -912,6 +923,7 @@ struct cpufreq_governor *cpufreq_default_governor(void) + cpufreq_governor_init(schedutil_gov); + + #ifdef CONFIG_ENERGY_MODEL ++#ifndef CONFIG_SCHED_PDS + extern bool sched_energy_update; + extern struct mutex sched_energy_mutex; + +@@ -942,4 +954,10 @@ void sched_cpufreq_governor_change(struct cpufreq_policy *policy, + } + + } ++#else /* CONFIG_SCHED_PDS */ ++void sched_cpufreq_governor_change(struct cpufreq_policy *policy, ++ struct cpufreq_governor *old_gov) ++{ ++} ++#endif + #endif +diff --git a/kernel/sched/cputime.c b/kernel/sched/cputime.c +index 5a55d2300452..76b956661488 100644 +--- a/kernel/sched/cputime.c ++++ b/kernel/sched/cputime.c +@@ -122,7 +122,12 @@ void account_user_time(struct task_struct *p, u64 cputime) + p->utime += cputime; + account_group_user_time(p, cputime); + ++#ifdef CONFIG_SCHED_PDS ++ index = (task_nice(p) > 0 || task_running_idle(p)) ? CPUTIME_NICE : ++ CPUTIME_USER; ++#else + index = (task_nice(p) > 0) ? CPUTIME_NICE : CPUTIME_USER; ++#endif + + /* Add user time to cpustat. */ + task_group_account_field(p, index, cputime); +@@ -146,7 +151,11 @@ void account_guest_time(struct task_struct *p, u64 cputime) + p->gtime += cputime; + + /* Add guest time to cpustat. */ ++#ifdef CONFIG_SCHED_PDS ++ if (task_nice(p) > 0 || task_running_idle(p)) { ++#else + if (task_nice(p) > 0) { ++#endif + cpustat[CPUTIME_NICE] += cputime; + cpustat[CPUTIME_GUEST_NICE] += cputime; + } else { +@@ -269,7 +278,7 @@ static inline u64 account_other_time(u64 max) + #ifdef CONFIG_64BIT + static inline u64 read_sum_exec_runtime(struct task_struct *t) + { +- return t->se.sum_exec_runtime; ++ return tsk_seruntime(t); + } + #else + static u64 read_sum_exec_runtime(struct task_struct *t) +@@ -279,7 +288,7 @@ static u64 read_sum_exec_runtime(struct task_struct *t) + struct rq *rq; + + rq = task_rq_lock(t, &rf); +- ns = t->se.sum_exec_runtime; ++ ns = tsk_seruntime(t); + task_rq_unlock(rq, t, &rf); + + return ns; +@@ -614,7 +623,7 @@ void cputime_adjust(struct task_cputime *curr, struct prev_cputime *prev, + void task_cputime_adjusted(struct task_struct *p, u64 *ut, u64 *st) + { + struct task_cputime cputime = { +- .sum_exec_runtime = p->se.sum_exec_runtime, ++ .sum_exec_runtime = tsk_seruntime(p), + }; + + task_cputime(p, &cputime.utime, &cputime.stime); +diff --git a/kernel/sched/idle.c b/kernel/sched/idle.c +index f324dc36fc43..80d841a6565e 100644 +--- a/kernel/sched/idle.c ++++ b/kernel/sched/idle.c +@@ -369,6 +369,7 @@ void cpu_startup_entry(enum cpuhp_state state) + do_idle(); + } + ++#ifndef CONFIG_SCHED_PDS + /* + * idle-task scheduling class. + */ +@@ -482,3 +483,4 @@ const struct sched_class idle_sched_class + .switched_to = switched_to_idle, + .update_curr = update_curr_idle, + }; ++#endif +diff --git a/kernel/sched/pds.c b/kernel/sched/pds.c +new file mode 100644 +index 000000000000..6e3920b03756 +--- /dev/null ++++ b/kernel/sched/pds.c +@@ -0,0 +1,6803 @@ ++/* ++ * kernel/sched/pds.c, was kernel/sched.c ++ * ++ * PDS-mq Core kernel scheduler code and related syscalls ++ * ++ * Copyright (C) 1991-2002 Linus Torvalds ++ * ++ * 2009-08-13 Brainfuck deadline scheduling policy by Con Kolivas deletes ++ * a whole lot of those previous things. ++ * 2017-09-06 Priority and Deadline based Skip list multiple queue kernel ++ * scheduler by Alfred Chen. ++ */ ++#define CREATE_TRACE_POINTS ++#include ++#undef CREATE_TRACE_POINTS ++ ++#include "pds_sched.h" ++ ++#include ++ ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++ ++#include ++ ++#include ++ ++#include "../workqueue_internal.h" ++#include "../../fs/io-wq.h" ++#include "../smpboot.h" ++ ++#include "pelt.h" ++#include "smp.h" ++ ++/* ++ * Export tracepoints that act as a bare tracehook (ie: have no trace event ++ * associated with them) to allow external modules to probe them. ++ */ ++EXPORT_TRACEPOINT_SYMBOL_GPL(pelt_irq_tp); ++ ++ ++#define rt_prio(prio) ((prio) < MAX_RT_PRIO) ++#define rt_task(p) rt_prio((p)->prio) ++#define rt_policy(policy) ((policy) == SCHED_FIFO || \ ++ (policy) == SCHED_RR || \ ++ (policy) == SCHED_ISO) ++#define task_has_rt_policy(p) (rt_policy((p)->policy)) ++ ++#define idle_policy(policy) ((policy) == SCHED_IDLE) ++#define idleprio_task(p) unlikely(idle_policy((p)->policy)) ++ ++#define STOP_PRIO (MAX_RT_PRIO - 1) ++ ++/* ++ * Some helpers for converting to/from various scales. Use shifts to get ++ * approximate multiples of ten for less overhead. ++ */ ++#define JIFFIES_TO_NS(TIME) ((TIME) * (1000000000 / HZ)) ++#define JIFFY_NS (1000000000 / HZ) ++#define HALF_JIFFY_NS (1000000000 / HZ / 2) ++#define HALF_JIFFY_US (1000000 / HZ / 2) ++#define MS_TO_NS(TIME) ((TIME) << 20) ++#define MS_TO_US(TIME) ((TIME) << 10) ++#define NS_TO_MS(TIME) ((TIME) >> 20) ++#define NS_TO_US(TIME) ((TIME) >> 10) ++#define US_TO_NS(TIME) ((TIME) << 10) ++ ++#define RESCHED_US (100) /* Reschedule if less than this many μs left */ ++ ++enum { ++ BASE_CPU_AFFINITY_CHK_LEVEL = 1, ++#ifdef CONFIG_SCHED_SMT ++ SMT_CPU_AFFINITY_CHK_LEVEL_SPACE_HOLDER, ++#endif ++#ifdef CONFIG_SCHED_MC ++ MC_CPU_AFFINITY_CHK_LEVEL_SPACE_HOLDER, ++#endif ++ NR_CPU_AFFINITY_CHK_LEVEL ++}; ++ ++static inline void print_scheduler_version(void) ++{ ++ printk(KERN_INFO "pds: PDS-mq CPU Scheduler 0.99o by Alfred Chen and kept alive artificially by Tk-Glitch.\n"); ++} ++ ++/* ++ * This is the time all tasks within the same priority round robin. ++ * Value is in ms and set to a minimum of 6ms. Scales with number of cpus. ++ * Tunable via /proc interface. ++ */ ++#define SCHED_DEFAULT_RR (4) ++int rr_interval __read_mostly = SCHED_DEFAULT_RR; ++ ++static int __init rr_interval_set(char *str) ++{ ++ u32 rr; ++ ++ pr_info("rr_interval: "); ++ if (kstrtouint(str, 0, &rr)) { ++ pr_cont("using default of %u, unable to parse %s\n", ++ rr_interval, str); ++ return 1; ++ } ++ ++ rr_interval = rr; ++ pr_cont("%d\n", rr_interval); ++ ++ return 1; ++} ++__setup("rr_interval=", rr_interval_set); ++ ++ ++static const u64 sched_prio2deadline[NICE_WIDTH] = { ++/* -20 */ 6291456, 6920601, 7612661, 8373927, 9211319, ++/* -15 */ 10132450, 11145695, 12260264, 13486290, 14834919, ++/* -10 */ 16318410, 17950251, 19745276, 21719803, 23891783, ++/* -5 */ 26280961, 28909057, 31799962, 34979958, 38477953, ++/* 0 */ 42325748, 46558322, 51214154, 56335569, 61969125, ++/* 5 */ 68166037, 74982640, 82480904, 90728994, 99801893, ++/* 10 */ 109782082, 120760290, 132836319, 146119950, 160731945, ++/* 15 */ 176805139, 194485652, 213934217, 235327638, 258860401 ++}; ++ ++/** ++ * sched_yield_type - Choose what sort of yield sched_yield will perform. ++ * 0: No yield. ++ * 1: Yield only to better priority/deadline tasks. (default) ++ * 2: Expire timeslice and recalculate deadline. ++ */ ++int sched_yield_type __read_mostly = 1; ++ ++/* ++ * The quota handed out to tasks of all priority levels when refilling their ++ * time_slice. ++ */ ++static inline int timeslice(void) ++{ ++ return MS_TO_US(rr_interval); ++} ++ ++#ifdef CONFIG_SMP ++enum { ++SCHED_RQ_EMPTY = 0, ++SCHED_RQ_IDLE, ++SCHED_RQ_NORMAL_0, ++SCHED_RQ_NORMAL_1, ++SCHED_RQ_NORMAL_2, ++SCHED_RQ_NORMAL_3, ++SCHED_RQ_NORMAL_4, ++SCHED_RQ_NORMAL_5, ++SCHED_RQ_NORMAL_6, ++SCHED_RQ_NORMAL_7, ++SCHED_RQ_ISO, ++SCHED_RQ_RT, ++NR_SCHED_RQ_QUEUED_LEVEL ++}; ++ ++static cpumask_t sched_rq_queued_masks[NR_SCHED_RQ_QUEUED_LEVEL] ++____cacheline_aligned_in_smp; ++ ++static DECLARE_BITMAP(sched_rq_queued_masks_bitmap, NR_SCHED_RQ_QUEUED_LEVEL) ++____cacheline_aligned_in_smp; ++ ++static cpumask_t sched_rq_pending_masks[NR_SCHED_RQ_QUEUED_LEVEL] ++____cacheline_aligned_in_smp; ++ ++static DECLARE_BITMAP(sched_rq_pending_masks_bitmap, NR_SCHED_RQ_QUEUED_LEVEL) ++____cacheline_aligned_in_smp; ++ ++DEFINE_PER_CPU(cpumask_t [NR_CPU_AFFINITY_CHK_LEVEL], sched_cpu_affinity_chk_masks); ++DEFINE_PER_CPU(cpumask_t *, sched_cpu_llc_start_mask); ++DEFINE_PER_CPU(cpumask_t *, sched_cpu_affinity_chk_end_masks); ++ ++#ifdef CONFIG_SCHED_SMT ++DEFINE_PER_CPU(int, sched_sibling_cpu); ++DEFINE_STATIC_KEY_FALSE(sched_smt_present); ++EXPORT_SYMBOL_GPL(sched_smt_present); ++ ++static cpumask_t sched_cpu_sg_idle_mask ____cacheline_aligned_in_smp; ++ ++#ifdef CONFIG_SMT_NICE ++/* ++ * Preemptible sibling group mask ++ * Which all sibling cpus are running at PRIO_LIMIT or IDLE_PRIO ++ */ ++static cpumask_t sched_cpu_psg_mask ____cacheline_aligned_in_smp; ++/* ++ * SMT supressed mask ++ * When a cpu is running task with NORMAL/ISO/RT policy, its sibling cpu ++ * will be supressed to run IDLE priority task. ++ */ ++static cpumask_t sched_smt_supressed_mask ____cacheline_aligned_in_smp; ++#endif /* CONFIG_SMT_NICE */ ++#endif ++ ++static int sched_rq_prio[NR_CPUS] ____cacheline_aligned; ++ ++/* ++ * Keep a unique ID per domain (we use the first CPUs number in the cpumask of ++ * the domain), this allows us to quickly tell if two cpus are in the same cache ++ * domain, see cpus_share_cache(). ++ */ ++DEFINE_PER_CPU(int, sd_llc_id); ++ ++int __weak arch_sd_sibling_asym_packing(void) ++{ ++ return 0*SD_ASYM_PACKING; ++} ++#else ++struct rq *uprq; ++#endif /* CONFIG_SMP */ ++ ++static DEFINE_MUTEX(sched_hotcpu_mutex); ++ ++DEFINE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues); ++ ++#ifndef prepare_arch_switch ++# define prepare_arch_switch(next) do { } while (0) ++#endif ++#ifndef finish_arch_post_lock_switch ++# define finish_arch_post_lock_switch() do { } while (0) ++#endif ++ ++/* ++ * Serialization rules: ++ * ++ * Lock order: ++ * ++ * p->pi_lock ++ * rq->lock ++ * hrtimer_cpu_base->lock (hrtimer_start() for bandwidth controls) ++ * ++ * rq1->lock ++ * rq2->lock where: rq1 < rq2 ++ * ++ * Regular state: ++ * ++ * Normal scheduling state is serialized by rq->lock. __schedule() takes the ++ * local CPU's rq->lock, it optionally removes the task from the runqueue and ++ * always looks at the local rq data structures to find the most elegible task ++ * to run next. ++ * ++ * Task enqueue is also under rq->lock, possibly taken from another CPU. ++ * Wakeups from another LLC domain might use an IPI to transfer the enqueue to ++ * the local CPU to avoid bouncing the runqueue state around [ see ++ * ttwu_queue_wakelist() ] ++ * ++ * Task wakeup, specifically wakeups that involve migration, are horribly ++ * complicated to avoid having to take two rq->locks. ++ * ++ * Special state: ++ * ++ * System-calls and anything external will use task_rq_lock() which acquires ++ * both p->pi_lock and rq->lock. As a consequence the state they change is ++ * stable while holding either lock: ++ * ++ * - sched_setaffinity()/ ++ * set_cpus_allowed_ptr(): p->cpus_ptr, p->nr_cpus_allowed ++ * - set_user_nice(): p->se.load, p->*prio ++ * - __sched_setscheduler(): p->sched_class, p->policy, p->*prio, ++ * p->se.load, p->rt_priority, ++ * p->dl.dl_{runtime, deadline, period, flags, bw, density} ++ * - sched_setnuma(): p->numa_preferred_nid ++ * - sched_move_task()/ ++ * cpu_cgroup_fork(): p->sched_task_group ++ * - uclamp_update_active() p->uclamp* ++ * ++ * p->state <- TASK_*: ++ * ++ * is changed locklessly using set_current_state(), __set_current_state() or ++ * set_special_state(), see their respective comments, or by ++ * try_to_wake_up(). This latter uses p->pi_lock to serialize against ++ * concurrent self. ++ * ++ * p->on_rq <- { 0, 1 = TASK_ON_RQ_QUEUED, 2 = TASK_ON_RQ_MIGRATING }: ++ * ++ * is set by activate_task() and cleared by deactivate_task(), under ++ * rq->lock. Non-zero indicates the task is runnable, the special ++ * ON_RQ_MIGRATING state is used for migration without holding both ++ * rq->locks. It indicates task_cpu() is not stable, see task_rq_lock(). ++ * ++ * p->on_cpu <- { 0, 1 }: ++ * ++ * is set by prepare_task() and cleared by finish_task() such that it will be ++ * set before p is scheduled-in and cleared after p is scheduled-out, both ++ * under rq->lock. Non-zero indicates the task is running on its CPU. ++ * ++ * [ The astute reader will observe that it is possible for two tasks on one ++ * CPU to have ->on_cpu = 1 at the same time. ] ++ * ++ * task_cpu(p): is changed by set_task_cpu(), the rules are: ++ * ++ * - Don't call set_task_cpu() on a blocked task: ++ * ++ * We don't care what CPU we're not running on, this simplifies hotplug, ++ * the CPU assignment of blocked tasks isn't required to be valid. ++ * ++ * - for try_to_wake_up(), called under p->pi_lock: ++ * ++ * This allows try_to_wake_up() to only take one rq->lock, see its comment. ++ * ++ * - for migration called under rq->lock: ++ * [ see task_on_rq_migrating() in task_rq_lock() ] ++ * ++ * o move_queued_task() ++ * o detach_task() ++ * ++ * - for migration called under double_rq_lock(): ++ * ++ * o __migrate_swap_task() ++ * o push_rt_task() / pull_rt_task() ++ * o push_dl_task() / pull_dl_task() ++ * o dl_task_offline_migration() ++ * ++ */ ++ ++/* ++ * Context: p->pi_lock ++ */ ++static inline struct rq ++*__task_access_lock(struct task_struct *p, raw_spinlock_t **plock) ++{ ++ struct rq *rq; ++ for (;;) { ++ rq = task_rq(p); ++ if (p->on_cpu || task_on_rq_queued(p)) { ++ raw_spin_lock(&rq->lock); ++ if (likely((p->on_cpu || task_on_rq_queued(p)) ++ && rq == task_rq(p))) { ++ *plock = &rq->lock; ++ return rq; ++ } ++ raw_spin_unlock(&rq->lock); ++ } else if (task_on_rq_migrating(p)) { ++ do { ++ cpu_relax(); ++ } while (unlikely(task_on_rq_migrating(p))); ++ } else { ++ *plock = NULL; ++ return rq; ++ } ++ } ++} ++ ++static inline void ++__task_access_unlock(struct task_struct *p, raw_spinlock_t *lock) ++{ ++ if (NULL != lock) ++ raw_spin_unlock(lock); ++} ++ ++static inline struct rq ++*task_access_lock_irqsave(struct task_struct *p, raw_spinlock_t **plock, ++ unsigned long *flags) ++{ ++ struct rq *rq; ++ for (;;) { ++ rq = task_rq(p); ++ if (p->on_cpu || task_on_rq_queued(p)) { ++ raw_spin_lock_irqsave(&rq->lock, *flags); ++ if (likely((p->on_cpu || task_on_rq_queued(p)) ++ && rq == task_rq(p))) { ++ *plock = &rq->lock; ++ return rq; ++ } ++ raw_spin_unlock_irqrestore(&rq->lock, *flags); ++ } else if (task_on_rq_migrating(p)) { ++ do { ++ cpu_relax(); ++ } while (unlikely(task_on_rq_migrating(p))); ++ } else { ++ raw_spin_lock_irqsave(&p->pi_lock, *flags); ++ if (likely(!p->on_cpu && !p->on_rq && ++ rq == task_rq(p))) { ++ *plock = &p->pi_lock; ++ return rq; ++ } ++ raw_spin_unlock_irqrestore(&p->pi_lock, *flags); ++ } ++ } ++} ++ ++static inline void ++task_access_unlock_irqrestore(struct task_struct *p, raw_spinlock_t *lock, ++ unsigned long *flags) ++{ ++ raw_spin_unlock_irqrestore(lock, *flags); ++} ++ ++/* ++ * __task_rq_lock - lock the rq @p resides on. ++ */ ++struct rq *__task_rq_lock(struct task_struct *p, struct rq_flags *rf) ++ __acquires(rq->lock) ++{ ++ struct rq *rq; ++ ++ lockdep_assert_held(&p->pi_lock); ++ ++ for (;;) { ++ rq = task_rq(p); ++ raw_spin_lock(&rq->lock); ++ if (likely(rq == task_rq(p) && !task_on_rq_migrating(p))) ++ return rq; ++ raw_spin_unlock(&rq->lock); ++ ++ while (unlikely(task_on_rq_migrating(p))) ++ cpu_relax(); ++ } ++} ++ ++/* ++ * task_rq_lock - lock p->pi_lock and lock the rq @p resides on. ++ */ ++struct rq *task_rq_lock(struct task_struct *p, struct rq_flags *rf) ++ __acquires(p->pi_lock) ++ __acquires(rq->lock) ++{ ++ struct rq *rq; ++ ++ for (;;) { ++ raw_spin_lock_irqsave(&p->pi_lock, rf->flags); ++ rq = task_rq(p); ++ raw_spin_lock(&rq->lock); ++ /* ++ * move_queued_task() task_rq_lock() ++ * ++ * ACQUIRE (rq->lock) ++ * [S] ->on_rq = MIGRATING [L] rq = task_rq() ++ * WMB (__set_task_cpu()) ACQUIRE (rq->lock); ++ * [S] ->cpu = new_cpu [L] task_rq() ++ * [L] ->on_rq ++ * RELEASE (rq->lock) ++ * ++ * If we observe the old CPU in task_rq_lock(), the acquire of ++ * the old rq->lock will fully serialize against the stores. ++ * ++ * If we observe the new CPU in task_rq_lock(), the address ++ * dependency headed by '[L] rq = task_rq()' and the acquire ++ * will pair with the WMB to ensure we then also see migrating. ++ */ ++ if (likely(rq == task_rq(p) && !task_on_rq_migrating(p))) { ++ return rq; ++ } ++ raw_spin_unlock(&rq->lock); ++ raw_spin_unlock_irqrestore(&p->pi_lock, rf->flags); ++ ++ while (unlikely(task_on_rq_migrating(p))) ++ cpu_relax(); ++ } ++} ++ ++/* ++ * RQ-clock updating methods: ++ */ ++ ++static void update_rq_clock_task(struct rq *rq, s64 delta) ++{ ++/* ++ * In theory, the compile should just see 0 here, and optimize out the call ++ * to sched_rt_avg_update. But I don't trust it... ++ */ ++ s64 __maybe_unused steal = 0, irq_delta = 0; ++ ++#ifdef CONFIG_IRQ_TIME_ACCOUNTING ++ irq_delta = irq_time_read(cpu_of(rq)) - rq->prev_irq_time; ++ ++ /* ++ * Since irq_time is only updated on {soft,}irq_exit, we might run into ++ * this case when a previous update_rq_clock() happened inside a ++ * {soft,}irq region. ++ * ++ * When this happens, we stop ->clock_task and only update the ++ * prev_irq_time stamp to account for the part that fit, so that a next ++ * update will consume the rest. This ensures ->clock_task is ++ * monotonic. ++ * ++ * It does however cause some slight miss-attribution of {soft,}irq ++ * time, a more accurate solution would be to update the irq_time using ++ * the current rq->clock timestamp, except that would require using ++ * atomic ops. ++ */ ++ if (irq_delta > delta) ++ irq_delta = delta; ++ ++ rq->prev_irq_time += irq_delta; ++ delta -= irq_delta; ++#endif ++#ifdef CONFIG_PARAVIRT_TIME_ACCOUNTING ++ if (static_key_false((¶virt_steal_rq_enabled))) { ++ steal = paravirt_steal_clock(cpu_of(rq)); ++ steal -= rq->prev_steal_time_rq; ++ ++ if (unlikely(steal > delta)) ++ steal = delta; ++ ++ rq->prev_steal_time_rq += steal; ++ ++ delta -= steal; ++ } ++#endif ++ ++ rq->clock_task += delta; ++ ++#ifdef CONFIG_HAVE_SCHED_AVG_IRQ ++ if ((irq_delta + steal)) ++ update_irq_load_avg(rq, irq_delta + steal); ++#endif ++} ++ ++static inline void update_rq_clock(struct rq *rq) ++{ ++ s64 delta = sched_clock_cpu(cpu_of(rq)) - rq->clock; ++ ++ if (unlikely(delta <= 0)) ++ return; ++ rq->clock += delta; ++ update_rq_clock_task(rq, delta); ++} ++ ++static inline void update_task_priodl(struct task_struct *p) ++{ ++ p->priodl = (((u64) (p->prio))<<56) | ((p->deadline)>>8); ++} ++ ++/* ++ * Deadline is "now" in niffies + (offset by priority). Setting the deadline ++ * is the key to everything. It distributes CPU fairly amongst tasks of the ++ * same nice value, it proportions CPU according to nice level, it means the ++ * task that last woke up the longest ago has the earliest deadline, thus ++ * ensuring that interactive tasks get low latency on wake up. The CPU ++ * proportion works out to the square of the virtual deadline difference, so ++ * this equation will give nice 19 3% CPU compared to nice 0. ++ */ ++static inline u64 task_deadline_diff(const struct task_struct *p) ++{ ++ return sched_prio2deadline[TASK_USER_PRIO(p)]; ++} ++ ++static inline u64 static_deadline_diff(int static_prio) ++{ ++ return sched_prio2deadline[USER_PRIO(static_prio)]; ++} ++ ++/* ++ * The time_slice is only refilled when it is empty and that is when we set a ++ * new deadline for non-rt tasks. ++ */ ++static inline void time_slice_expired(struct task_struct *p, struct rq *rq) ++{ ++ p->time_slice = timeslice(); ++ if (p->prio >= NORMAL_PRIO) ++ p->deadline = rq->clock + task_deadline_diff(p); ++ ++ update_task_priodl(p); ++} ++ ++static inline struct task_struct *rq_first_queued_task(struct rq *rq) ++{ ++ struct skiplist_node *node = rq->sl_header.next[0]; ++ ++ if (node == &rq->sl_header) ++ return rq->idle; ++ ++ return skiplist_entry(node, struct task_struct, sl_node); ++} ++ ++static inline struct task_struct *rq_second_queued_task(struct rq *rq) ++{ ++ struct skiplist_node *node = rq->sl_header.next[0]->next[0]; ++ ++ if (node == &rq->sl_header) ++ return rq->idle; ++ ++ return skiplist_entry(node, struct task_struct, sl_node); ++} ++ ++static inline int is_second_in_rq(struct task_struct *p, struct rq *rq) ++{ ++ return (p->sl_node.prev[0]->prev[0] == &rq->sl_header); ++} ++ ++static const int task_dl_hash_tbl[] = { ++/* 0 4 8 12 */ ++ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, ++/* 16 20 24 28 */ ++ 1, 1, 1, 2, 2, 2, 2, 2, 3, 3, 3, 4, 4, 5, 6, 7 ++}; ++ ++static inline int ++task_deadline_level(const struct task_struct *p, const struct rq *rq) ++{ ++ u64 delta = (rq->clock + sched_prio2deadline[39] - p->deadline) >> 23; ++ ++ delta = min((size_t)delta, ARRAY_SIZE(task_dl_hash_tbl) - 1); ++ return task_dl_hash_tbl[delta]; ++} ++ ++/* ++ * cmpxchg based fetch_or, macro so it works for different integer types ++ */ ++#define fetch_or(ptr, mask) \ ++ ({ \ ++ typeof(ptr) _ptr = (ptr); \ ++ typeof(mask) _mask = (mask); \ ++ typeof(*_ptr) _old, _val = *_ptr; \ ++ \ ++ for (;;) { \ ++ _old = cmpxchg(_ptr, _val, _val | _mask); \ ++ if (_old == _val) \ ++ break; \ ++ _val = _old; \ ++ } \ ++ _old; \ ++}) ++ ++#if defined(CONFIG_SMP) && defined(TIF_POLLING_NRFLAG) ++/* ++ * Atomically set TIF_NEED_RESCHED and test for TIF_POLLING_NRFLAG, ++ * this avoids any races wrt polling state changes and thereby avoids ++ * spurious IPIs. ++ */ ++static bool set_nr_and_not_polling(struct task_struct *p) ++{ ++ struct thread_info *ti = task_thread_info(p); ++ return !(fetch_or(&ti->flags, _TIF_NEED_RESCHED) & _TIF_POLLING_NRFLAG); ++} ++ ++/* ++ * Atomically set TIF_NEED_RESCHED if TIF_POLLING_NRFLAG is set. ++ * ++ * If this returns true, then the idle task promises to call ++ * flush_smp_call_function_from_idle() and reschedule soon. ++ */ ++static bool set_nr_if_polling(struct task_struct *p) ++{ ++ struct thread_info *ti = task_thread_info(p); ++ typeof(ti->flags) old, val = READ_ONCE(ti->flags); ++ ++ for (;;) { ++ if (!(val & _TIF_POLLING_NRFLAG)) ++ return false; ++ if (val & _TIF_NEED_RESCHED) ++ return true; ++ old = cmpxchg(&ti->flags, val, val | _TIF_NEED_RESCHED); ++ if (old == val) ++ break; ++ val = old; ++ } ++ return true; ++} ++ ++#else ++static bool set_nr_and_not_polling(struct task_struct *p) ++{ ++ set_tsk_need_resched(p); ++ return true; ++} ++ ++#ifdef CONFIG_SMP ++static bool set_nr_if_polling(struct task_struct *p) ++{ ++ return false; ++} ++#endif ++#endif ++ ++#ifdef CONFIG_SMP ++#ifdef CONFIG_SMT_NICE ++static void resched_cpu_if_curr_is(int cpu, int priority) ++{ ++ struct rq *rq = cpu_rq(cpu); ++ ++ rcu_read_lock(); ++ ++ if (rcu_dereference(rq->curr)->prio != priority) ++ goto out; ++ ++ if (set_nr_if_polling(rq->idle)) { ++ trace_sched_wake_idle_without_ipi(cpu); ++ } else { ++ if (!do_raw_spin_trylock(&rq->lock)) ++ goto out; ++ spin_acquire(&rq->lock.dep_map, SINGLE_DEPTH_NESTING, 1, _RET_IP_); ++ ++ if (priority == rq->curr->prio) ++ smp_send_reschedule(cpu); ++ /* Else CPU is not idle, do nothing here */ ++ ++ spin_release(&rq->lock.dep_map, _RET_IP_); ++ do_raw_spin_unlock(&rq->lock); ++ } ++ ++out: ++ rcu_read_unlock(); ++} ++#endif /* CONFIG_SMT_NICE */ ++ ++static inline bool ++__update_cpumasks_bitmap(int cpu, unsigned long *plevel, unsigned long level, ++ cpumask_t cpumasks[], unsigned long bitmap[]) ++{ ++ if (*plevel == level) ++ return false; ++ ++ cpumask_clear_cpu(cpu, cpumasks + *plevel); ++ if (cpumask_empty(cpumasks + *plevel)) ++ clear_bit(*plevel, bitmap); ++ cpumask_set_cpu(cpu, cpumasks + level); ++ set_bit(level, bitmap); ++ ++ *plevel = level; ++ ++ return true; ++} ++ ++static inline int ++task_running_policy_level(const struct task_struct *p, const struct rq *rq) ++{ ++ int prio = p->prio; ++ ++ if (NORMAL_PRIO == prio) ++ return SCHED_RQ_NORMAL_0 + task_deadline_level(p, rq); ++ ++ if (ISO_PRIO == prio) ++ return SCHED_RQ_ISO; ++ if (prio < MAX_RT_PRIO) ++ return SCHED_RQ_RT; ++ return PRIO_LIMIT - prio; ++} ++ ++static inline void update_sched_rq_queued_masks_normal(struct rq *rq) ++{ ++ struct task_struct *p = rq_first_queued_task(rq); ++ ++ if (p->prio != NORMAL_PRIO) ++ return; ++ ++ __update_cpumasks_bitmap(cpu_of(rq), &rq->queued_level, ++ task_running_policy_level(p, rq), ++ &sched_rq_queued_masks[0], ++ &sched_rq_queued_masks_bitmap[0]); ++} ++ ++#ifdef CONFIG_SMT_NICE ++static inline void update_sched_cpu_psg_mask(const int cpu) ++{ ++ cpumask_t tmp; ++ ++ cpumask_or(&tmp, &sched_rq_queued_masks[SCHED_RQ_EMPTY], ++ &sched_rq_queued_masks[SCHED_RQ_IDLE]); ++ cpumask_and(&tmp, &tmp, cpu_smt_mask(cpu)); ++ if (cpumask_equal(&tmp, cpu_smt_mask(cpu))) ++ cpumask_or(&sched_cpu_psg_mask, &sched_cpu_psg_mask, ++ cpu_smt_mask(cpu)); ++ else ++ cpumask_andnot(&sched_cpu_psg_mask, &sched_cpu_psg_mask, ++ cpu_smt_mask(cpu)); ++} ++#endif ++ ++static inline void update_sched_rq_queued_masks(struct rq *rq) ++{ ++ int cpu = cpu_of(rq); ++ struct task_struct *p = rq_first_queued_task(rq); ++ unsigned long level; ++#ifdef CONFIG_SCHED_SMT ++ unsigned long last_level = rq->queued_level; ++#endif ++ ++ level = task_running_policy_level(p, rq); ++ sched_rq_prio[cpu] = p->prio; ++ ++ if (!__update_cpumasks_bitmap(cpu, &rq->queued_level, level, ++ &sched_rq_queued_masks[0], ++ &sched_rq_queued_masks_bitmap[0])) ++ return; ++ ++#ifdef CONFIG_SCHED_SMT ++ if (cpu == per_cpu(sched_sibling_cpu, cpu)) ++ return; ++ ++ if (SCHED_RQ_EMPTY == last_level) { ++ cpumask_andnot(&sched_cpu_sg_idle_mask, &sched_cpu_sg_idle_mask, ++ cpu_smt_mask(cpu)); ++ } else if (SCHED_RQ_EMPTY == level) { ++ cpumask_t tmp; ++ ++ cpumask_and(&tmp, cpu_smt_mask(cpu), ++ &sched_rq_queued_masks[SCHED_RQ_EMPTY]); ++ if (cpumask_equal(&tmp, cpu_smt_mask(cpu))) ++ cpumask_or(&sched_cpu_sg_idle_mask, cpu_smt_mask(cpu), ++ &sched_cpu_sg_idle_mask); ++ } ++ ++#ifdef CONFIG_SMT_NICE ++ if (level <= SCHED_RQ_IDLE && last_level > SCHED_RQ_IDLE) { ++ cpumask_clear_cpu(per_cpu(sched_sibling_cpu, cpu), ++ &sched_smt_supressed_mask); ++ update_sched_cpu_psg_mask(cpu); ++ resched_cpu_if_curr_is(per_cpu(sched_sibling_cpu, cpu), PRIO_LIMIT); ++ } else if (last_level <= SCHED_RQ_IDLE && level > SCHED_RQ_IDLE) { ++ cpumask_set_cpu(per_cpu(sched_sibling_cpu, cpu), ++ &sched_smt_supressed_mask); ++ update_sched_cpu_psg_mask(cpu); ++ resched_cpu_if_curr_is(per_cpu(sched_sibling_cpu, cpu), IDLE_PRIO); ++ } ++#endif /* CONFIG_SMT_NICE */ ++#endif ++} ++ ++static inline void update_sched_rq_pending_masks(struct rq *rq) ++{ ++ unsigned long level; ++ struct task_struct *p = rq_second_queued_task(rq); ++ ++ level = task_running_policy_level(p, rq); ++ ++ __update_cpumasks_bitmap(cpu_of(rq), &rq->pending_level, level, ++ &sched_rq_pending_masks[0], ++ &sched_rq_pending_masks_bitmap[0]); ++} ++ ++#else /* CONFIG_SMP */ ++static inline void update_sched_rq_queued_masks(struct rq *rq) {} ++static inline void update_sched_rq_queued_masks_normal(struct rq *rq) {} ++static inline void update_sched_rq_pending_masks(struct rq *rq) {} ++#endif ++ ++#ifdef CONFIG_NO_HZ_FULL ++/* ++ * Tick may be needed by tasks in the runqueue depending on their policy and ++ * requirements. If tick is needed, lets send the target an IPI to kick it out ++ * of nohz mode if necessary. ++ */ ++static inline void sched_update_tick_dependency(struct rq *rq) ++{ ++ int cpu = cpu_of(rq); ++ ++ if (!tick_nohz_full_cpu(cpu)) ++ return; ++ ++ if (rq->nr_running < 2) ++ tick_nohz_dep_clear_cpu(cpu, TICK_DEP_BIT_SCHED); ++ else ++ tick_nohz_dep_set_cpu(cpu, TICK_DEP_BIT_SCHED); ++} ++#else /* !CONFIG_NO_HZ_FULL */ ++static inline void sched_update_tick_dependency(struct rq *rq) { } ++#endif ++ ++/* ++ * Removing from the runqueue. Deleting a task from the skip list is done ++ * via the stored node reference in the task struct and does not require a full ++ * look up. Thus it occurs in O(k) time where k is the "level" of the list the ++ * task was stored at - usually < 4, max 16. ++ * ++ * Context: rq->lock ++ */ ++static inline void dequeue_task(struct task_struct *p, struct rq *rq, int flags) ++{ ++ lockdep_assert_held(&rq->lock); ++ ++ WARN_ONCE(task_rq(p) != rq, "pds: dequeue task reside on cpu%d from cpu%d\n", ++ task_cpu(p), cpu_of(rq)); ++ if (skiplist_del_init(&rq->sl_header, &p->sl_node)) { ++ update_sched_rq_queued_masks(rq); ++ update_sched_rq_pending_masks(rq); ++ } else if (is_second_in_rq(p, rq)) ++ update_sched_rq_pending_masks(rq); ++ rq->nr_running--; ++ ++ sched_update_tick_dependency(rq); ++ psi_dequeue(p, flags & DEQUEUE_SLEEP); ++ ++ sched_info_dequeued(rq, p); ++} ++ ++/* ++ * To determine if it's safe for a task of SCHED_IDLE to actually run as ++ * an idle task, we ensure none of the following conditions are met. ++ */ ++static inline bool idleprio_suitable(struct task_struct *p) ++{ ++ return (!freezing(p) && !signal_pending(p) && ++ !(task_contributes_to_load(p)) && !(p->flags & (PF_EXITING))); ++} ++ ++/* ++ * pds_skiplist_random_level -- Returns a pseudo-random level number for skip ++ * list node which is used in PDS run queue. ++ * ++ * In current implementation, based on testing, the first 8 bits in microseconds ++ * of niffies are suitable for random level population. ++ * find_first_bit() is used to satisfy p = 0.5 between each levels, and there ++ * should be platform hardware supported instruction(known as ctz/clz) to speed ++ * up this function. ++ * The skiplist level for a task is populated when task is created and doesn't ++ * change in task's life time. When task is being inserted into run queue, this ++ * skiplist level is set to task's sl_node->level, the skiplist insert function ++ * may change it based on current level of the skip lsit. ++ */ ++static inline int pds_skiplist_random_level(const struct task_struct *p) ++{ ++ long unsigned int randseed; ++ ++ /* ++ * 1. Some architectures don't have better than microsecond resolution ++ * so mask out ~microseconds as a factor of the random seed for skiplist ++ * insertion. ++ * 2. Use address of task structure pointer as another factor of the ++ * random seed for task burst forking scenario. ++ */ ++ randseed = (task_rq(p)->clock ^ (long unsigned int)p) >> 10; ++ ++ return find_first_bit(&randseed, NUM_SKIPLIST_LEVEL - 1); ++} ++ ++/** ++ * pds_skiplist_task_search -- search function used in PDS run queue skip list ++ * node insert operation. ++ * @it: iterator pointer to the node in the skip list ++ * @node: pointer to the skiplist_node to be inserted ++ * ++ * Returns true if key of @it is less or equal to key value of @node, otherwise ++ * false. ++ */ ++static inline bool ++pds_skiplist_task_search(struct skiplist_node *it, struct skiplist_node *node) ++{ ++ return (skiplist_entry(it, struct task_struct, sl_node)->priodl <= ++ skiplist_entry(node, struct task_struct, sl_node)->priodl); ++} ++ ++/* ++ * Define the skip list insert function for PDS ++ */ ++DEFINE_SKIPLIST_INSERT_FUNC(pds_skiplist_insert, pds_skiplist_task_search); ++ ++/* ++ * Adding task to the runqueue. ++ * ++ * Context: rq->lock ++ */ ++static inline void enqueue_task(struct task_struct *p, struct rq *rq, int flags) ++{ ++ lockdep_assert_held(&rq->lock); ++ ++ WARN_ONCE(task_rq(p) != rq, "pds: enqueue task reside on cpu%d to cpu%d\n", ++ task_cpu(p), cpu_of(rq)); ++ ++ p->sl_node.level = p->sl_level; ++ if (pds_skiplist_insert(&rq->sl_header, &p->sl_node)) { ++ update_sched_rq_queued_masks(rq); ++ update_sched_rq_pending_masks(rq); ++ } else if (is_second_in_rq(p, rq)) ++ update_sched_rq_pending_masks(rq); ++ rq->nr_running++; ++ ++ sched_update_tick_dependency(rq); ++ ++ sched_info_queued(rq, p); ++ psi_enqueue(p, flags); ++ ++ /* ++ * If in_iowait is set, the code below may not trigger any cpufreq ++ * utilization updates, so do it here explicitly with the IOWAIT flag ++ * passed. ++ */ ++ if (p->in_iowait) ++ cpufreq_update_this_cpu(rq, SCHED_CPUFREQ_IOWAIT); ++} ++ ++static inline void requeue_task(struct task_struct *p, struct rq *rq) ++{ ++ bool b_first, b_second; ++ ++ lockdep_assert_held(&rq->lock); ++ ++ WARN_ONCE(task_rq(p) != rq, "pds: cpu[%d] requeue task reside on cpu%d\n", ++ cpu_of(rq), task_cpu(p)); ++ ++ b_first = skiplist_del_init(&rq->sl_header, &p->sl_node); ++ b_second = is_second_in_rq(p, rq); ++ ++ p->sl_node.level = p->sl_level; ++ if (pds_skiplist_insert(&rq->sl_header, &p->sl_node) || b_first) { ++ update_sched_rq_queued_masks(rq); ++ update_sched_rq_pending_masks(rq); ++ } else if (is_second_in_rq(p, rq) || b_second) ++ update_sched_rq_pending_masks(rq); ++} ++ ++/* ++ * resched_curr - mark rq's current task 'to be rescheduled now'. ++ * ++ * On UP this means the setting of the need_resched flag, on SMP it ++ * might also involve a cross-CPU call to trigger the scheduler on ++ * the target CPU. ++ */ ++void resched_curr(struct rq *rq) ++{ ++ struct task_struct *curr = rq->curr; ++ int cpu; ++ ++ lockdep_assert_held(&rq->lock); ++ ++ if (test_tsk_need_resched(curr)) ++ return; ++ ++ cpu = cpu_of(rq); ++ if (cpu == smp_processor_id()) { ++ set_tsk_need_resched(curr); ++ set_preempt_need_resched(); ++ return; ++ } ++ ++ if (set_nr_and_not_polling(curr)) ++ smp_send_reschedule(cpu); ++ else ++ trace_sched_wake_idle_without_ipi(cpu); ++} ++ ++static inline void check_preempt_curr(struct rq *rq, struct task_struct *p) ++{ ++ struct task_struct *curr = rq->curr; ++ ++ if (curr->prio == PRIO_LIMIT) ++ resched_curr(rq); ++ ++ if (task_running_idle(p)) ++ return; ++ ++ if (p->priodl < curr->priodl) ++ resched_curr(rq); ++} ++ ++#ifdef CONFIG_SCHED_HRTICK ++/* ++ * Use HR-timers to deliver accurate preemption points. ++ */ ++ ++static void hrtick_clear(struct rq *rq) ++{ ++ if (hrtimer_active(&rq->hrtick_timer)) ++ hrtimer_cancel(&rq->hrtick_timer); ++} ++ ++/* ++ * High-resolution timer tick. ++ * Runs from hardirq context with interrupts disabled. ++ */ ++static enum hrtimer_restart hrtick(struct hrtimer *timer) ++{ ++ struct rq *rq = container_of(timer, struct rq, hrtick_timer); ++ struct task_struct *p; ++ ++ WARN_ON_ONCE(cpu_of(rq) != smp_processor_id()); ++ ++ raw_spin_lock(&rq->lock); ++ p = rq->curr; ++ p->time_slice = 0; ++ resched_curr(rq); ++ raw_spin_unlock(&rq->lock); ++ ++ return HRTIMER_NORESTART; ++} ++ ++/* ++ * Use hrtick when: ++ * - enabled by features ++ * - hrtimer is actually high res ++ */ ++static inline int hrtick_enabled(struct rq *rq) ++{ ++ /** ++ * PDS doesn't support sched_feat yet ++ if (!sched_feat(HRTICK)) ++ return 0; ++ */ ++ if (!cpu_active(cpu_of(rq))) ++ return 0; ++ return hrtimer_is_hres_active(&rq->hrtick_timer); ++} ++ ++#ifdef CONFIG_SMP ++ ++static void __hrtick_restart(struct rq *rq) ++{ ++ struct hrtimer *timer = &rq->hrtick_timer; ++ ++ hrtimer_start_expires(timer, HRTIMER_MODE_ABS_PINNED_HARD); ++} ++ ++/* ++ * called from hardirq (IPI) context ++ */ ++static void __hrtick_start(void *arg) ++{ ++ struct rq *rq = arg; ++ ++ raw_spin_lock(&rq->lock); ++ __hrtick_restart(rq); ++ raw_spin_unlock(&rq->lock); ++} ++ ++/* ++ * Called to set the hrtick timer state. ++ * ++ * called with rq->lock held and irqs disabled ++ */ ++void hrtick_start(struct rq *rq, u64 delay) ++{ ++ struct hrtimer *timer = &rq->hrtick_timer; ++ ktime_t time; ++ s64 delta; ++ ++ /* ++ * Don't schedule slices shorter than 10000ns, that just ++ * doesn't make sense and can cause timer DoS. ++ */ ++ delta = max_t(s64, delay, 10000LL); ++ time = ktime_add_ns(timer->base->get_time(), delta); ++ ++ hrtimer_set_expires(timer, time); ++ ++ if (rq == this_rq()) ++ __hrtick_restart(rq); ++ else ++ smp_call_function_single_async(cpu_of(rq), &rq->hrtick_csd); ++} ++ ++#else ++/* ++ * Called to set the hrtick timer state. ++ * ++ * called with rq->lock held and irqs disabled ++ */ ++void hrtick_start(struct rq *rq, u64 delay) ++{ ++ /* ++ * Don't schedule slices shorter than 10000ns, that just ++ * doesn't make sense. Rely on vruntime for fairness. ++ */ ++ delay = max_t(u64, delay, 10000LL); ++ hrtimer_start(&rq->hrtick_timer, ns_to_ktime(delay), ++ HRTIMER_MODE_REL_PINNED_HARD); ++} ++#endif /* CONFIG_SMP */ ++ ++static void hrtick_rq_init(struct rq *rq) ++{ ++#ifdef CONFIG_SMP ++ rq->hrtick_csd.flags = 0; ++ rq->hrtick_csd.func = __hrtick_start; ++ rq->hrtick_csd.info = rq; ++#endif ++ ++ hrtimer_init(&rq->hrtick_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_HARD); ++ rq->hrtick_timer.function = hrtick; ++} ++ ++static inline int rq_dither(struct rq *rq) ++{ ++ if ((rq->clock - rq->last_tick > HALF_JIFFY_NS) || hrtick_enabled(rq)) ++ return 0; ++ ++ return HALF_JIFFY_NS; ++} ++ ++#else /* CONFIG_SCHED_HRTICK */ ++static inline int hrtick_enabled(struct rq *rq) ++{ ++ return 0; ++} ++ ++static inline void hrtick_clear(struct rq *rq) ++{ ++} ++ ++static inline void hrtick_rq_init(struct rq *rq) ++{ ++} ++ ++static inline int rq_dither(struct rq *rq) ++{ ++ return (rq->clock - rq->last_tick > HALF_JIFFY_NS)? 0:HALF_JIFFY_NS; ++} ++#endif /* CONFIG_SCHED_HRTICK */ ++ ++static inline int normal_prio(struct task_struct *p) ++{ ++ static const int policy_to_prio[] = { ++ NORMAL_PRIO, /* SCHED_NORMAL */ ++ 0, /* SCHED_FIFO */ ++ 0, /* SCHED_RR */ ++ IDLE_PRIO, /* SCHED_BATCH */ ++ ISO_PRIO, /* SCHED_ISO */ ++ IDLE_PRIO /* SCHED_IDLE */ ++ }; ++ ++ if (task_has_rt_policy(p)) ++ return MAX_RT_PRIO - 1 - p->rt_priority; ++ return policy_to_prio[p->policy]; ++} ++ ++/* ++ * Calculate the current priority, i.e. the priority ++ * taken into account by the scheduler. This value might ++ * be boosted by RT tasks as it will be RT if the task got ++ * RT-boosted. If not then it returns p->normal_prio. ++ */ ++static int effective_prio(struct task_struct *p) ++{ ++ p->normal_prio = normal_prio(p); ++ /* ++ * If we are RT tasks or we were boosted to RT priority, ++ * keep the priority unchanged. Otherwise, update priority ++ * to the normal priority: ++ */ ++ if (!rt_prio(p->prio)) ++ return p->normal_prio; ++ return p->prio; ++} ++ ++/* ++ * activate_task - move a task to the runqueue. ++ * ++ * Context: rq->lock ++ */ ++static void activate_task(struct task_struct *p, struct rq *rq) ++{ ++ if (task_contributes_to_load(p)) ++ rq->nr_uninterruptible--; ++ enqueue_task(p, rq, ENQUEUE_WAKEUP); ++ p->on_rq = 1; ++ cpufreq_update_this_cpu(rq, 0); ++} ++ ++/* ++ * deactivate_task - remove a task from the runqueue. ++ * ++ * Context: rq->lock ++ */ ++static inline void deactivate_task(struct task_struct *p, struct rq *rq) ++{ ++ if (task_contributes_to_load(p)) ++ rq->nr_uninterruptible++; ++ dequeue_task(p, rq, DEQUEUE_SLEEP); ++ p->on_rq = 0; ++ cpufreq_update_this_cpu(rq, 0); ++} ++ ++static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu) ++{ ++#ifdef CONFIG_SMP ++ /* ++ * After ->cpu is set up to a new value, task_access_lock(p, ...) can be ++ * successfully executed on another CPU. We must ensure that updates of ++ * per-task data have been completed by this moment. ++ */ ++ smp_wmb(); ++ ++#ifdef CONFIG_THREAD_INFO_IN_TASK ++ WRITE_ONCE(p->cpu, cpu); ++#else ++ WRITE_ONCE(task_thread_info(p)->cpu, cpu); ++#endif ++#endif ++} ++ ++#ifdef CONFIG_SMP ++void set_task_cpu(struct task_struct *p, unsigned int new_cpu) ++{ ++#ifdef CONFIG_SCHED_DEBUG ++ /* ++ * We should never call set_task_cpu() on a blocked task, ++ * ttwu() will sort out the placement. ++ */ ++ WARN_ON_ONCE(p->state != TASK_RUNNING && p->state != TASK_WAKING && ++ !p->on_rq); ++#ifdef CONFIG_LOCKDEP ++ /* ++ * The caller should hold either p->pi_lock or rq->lock, when changing ++ * a task's CPU. ->pi_lock for waking tasks, rq->lock for runnable tasks. ++ * ++ * sched_move_task() holds both and thus holding either pins the cgroup, ++ * see task_group(). ++ */ ++ WARN_ON_ONCE(debug_locks && !(lockdep_is_held(&p->pi_lock) || ++ lockdep_is_held(&task_rq(p)->lock))); ++#endif ++ /* ++ * Clearly, migrating tasks to offline CPUs is a fairly daft thing. ++ */ ++ WARN_ON_ONCE(!cpu_online(new_cpu)); ++#endif ++ if (task_cpu(p) == new_cpu) ++ return; ++ trace_sched_migrate_task(p, new_cpu); ++ rseq_migrate(p); ++ perf_event_task_migrate(p); ++ ++ __set_task_cpu(p, new_cpu); ++} ++ ++static inline bool is_per_cpu_kthread(struct task_struct *p) ++{ ++ return ((p->flags & PF_KTHREAD) && (1 == p->nr_cpus_allowed)); ++} ++ ++/* ++ * Per-CPU kthreads are allowed to run on !active && online CPUs, see ++ * __set_cpus_allowed_ptr() and select_fallback_rq(). ++ */ ++static inline bool is_cpu_allowed(struct task_struct *p, int cpu) ++{ ++ if (!cpumask_test_cpu(cpu, &p->cpus_mask)) ++ return false; ++ ++ if (is_per_cpu_kthread(p)) ++ return cpu_online(cpu); ++ ++ return cpu_active(cpu); ++} ++ ++/* ++ * This is how migration works: ++ * ++ * 1) we invoke migration_cpu_stop() on the target CPU using ++ * stop_one_cpu(). ++ * 2) stopper starts to run (implicitly forcing the migrated thread ++ * off the CPU) ++ * 3) it checks whether the migrated task is still in the wrong runqueue. ++ * 4) if it's in the wrong runqueue then the migration thread removes ++ * it and puts it into the right queue. ++ * 5) stopper completes and stop_one_cpu() returns and the migration ++ * is done. ++ */ ++ ++/* ++ * move_queued_task - move a queued task to new rq. ++ * ++ * Returns (locked) new rq. Old rq's lock is released. ++ */ ++static struct rq *move_queued_task(struct rq *rq, struct task_struct *p, int ++ new_cpu) ++{ ++ lockdep_assert_held(&rq->lock); ++ ++ p->on_rq = TASK_ON_RQ_MIGRATING; ++ dequeue_task(p, rq, 0); ++ set_task_cpu(p, new_cpu); ++ raw_spin_unlock(&rq->lock); ++ ++ rq = cpu_rq(new_cpu); ++ ++ raw_spin_lock(&rq->lock); ++ BUG_ON(task_cpu(p) != new_cpu); ++ enqueue_task(p, rq, 0); ++ p->on_rq = TASK_ON_RQ_QUEUED; ++ check_preempt_curr(rq, p); ++ ++ return rq; ++} ++ ++struct migration_arg { ++ struct task_struct *task; ++ int dest_cpu; ++}; ++ ++/* ++ * Move (not current) task off this CPU, onto the destination CPU. We're doing ++ * this because either it can't run here any more (set_cpus_allowed() ++ * away from this CPU, or CPU going down), or because we're ++ * attempting to rebalance this task on exec (sched_exec). ++ * ++ * So we race with normal scheduler movements, but that's OK, as long ++ * as the task is no longer on this CPU. ++ */ ++static struct rq *__migrate_task(struct rq *rq, struct task_struct *p, int ++ dest_cpu) ++{ ++ /* Affinity changed (again). */ ++ if (!is_cpu_allowed(p, dest_cpu)) ++ return rq; ++ ++ update_rq_clock(rq); ++ return move_queued_task(rq, p, dest_cpu); ++} ++ ++/* ++ * migration_cpu_stop - this will be executed by a highprio stopper thread ++ * and performs thread migration by bumping thread off CPU then ++ * 'pushing' onto another runqueue. ++ */ ++static int migration_cpu_stop(void *data) ++{ ++ struct migration_arg *arg = data; ++ struct task_struct *p = arg->task; ++ struct rq *rq = this_rq(); ++ ++ /* ++ * The original target CPU might have gone down and we might ++ * be on another CPU but it doesn't matter. ++ */ ++ local_irq_disable(); ++ ++ raw_spin_lock(&p->pi_lock); ++ raw_spin_lock(&rq->lock); ++ /* ++ * If task_rq(p) != rq, it cannot be migrated here, because we're ++ * holding rq->lock, if p->on_rq == 0 it cannot get enqueued because ++ * we're holding p->pi_lock. ++ */ ++ if (task_rq(p) == rq) ++ if (task_on_rq_queued(p)) ++ rq = __migrate_task(rq, p, arg->dest_cpu); ++ raw_spin_unlock(&rq->lock); ++ raw_spin_unlock(&p->pi_lock); ++ ++ local_irq_enable(); ++ return 0; ++} ++ ++static inline void ++set_cpus_allowed_common(struct task_struct *p, const struct cpumask *new_mask) ++{ ++ cpumask_copy(&p->cpus_mask, new_mask); ++ p->nr_cpus_allowed = cpumask_weight(new_mask); ++} ++ ++void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask) ++{ ++ set_cpus_allowed_common(p, new_mask); ++} ++#endif ++ ++/* Enter with rq lock held. We know p is on the local CPU */ ++static inline void __set_tsk_resched(struct task_struct *p) ++{ ++ set_tsk_need_resched(p); ++ set_preempt_need_resched(); ++} ++ ++/** ++ * task_curr - is this task currently executing on a CPU? ++ * @p: the task in question. ++ * ++ * Return: 1 if the task is currently executing. 0 otherwise. ++ */ ++inline int task_curr(const struct task_struct *p) ++{ ++ return cpu_curr(task_cpu(p)) == p; ++} ++ ++#ifdef CONFIG_SMP ++/* ++ * wait_task_inactive - wait for a thread to unschedule. ++ * ++ * If @match_state is nonzero, it's the @p->state value just checked and ++ * not expected to change. If it changes, i.e. @p might have woken up, ++ * then return zero. When we succeed in waiting for @p to be off its CPU, ++ * we return a positive number (its total switch count). If a second call ++ * a short while later returns the same number, the caller can be sure that ++ * @p has remained unscheduled the whole time. ++ * ++ * The caller must ensure that the task *will* unschedule sometime soon, ++ * else this function might spin for a *long* time. This function can't ++ * be called with interrupts off, or it may introduce deadlock with ++ * smp_call_function() if an IPI is sent by the same process we are ++ * waiting to become inactive. ++ */ ++unsigned long wait_task_inactive(struct task_struct *p, long match_state) ++{ ++ unsigned long flags; ++ bool running, on_rq; ++ unsigned long ncsw; ++ struct rq *rq; ++ raw_spinlock_t *lock; ++ ++ for (;;) { ++ rq = task_rq(p); ++ ++ /* ++ * If the task is actively running on another CPU ++ * still, just relax and busy-wait without holding ++ * any locks. ++ * ++ * NOTE! Since we don't hold any locks, it's not ++ * even sure that "rq" stays as the right runqueue! ++ * But we don't care, since this will return false ++ * if the runqueue has changed and p is actually now ++ * running somewhere else! ++ */ ++ while (task_running(p) && p == rq->curr) { ++ if (match_state && unlikely(p->state != match_state)) ++ return 0; ++ cpu_relax(); ++ } ++ ++ /* ++ * Ok, time to look more closely! We need the rq ++ * lock now, to be *sure*. If we're wrong, we'll ++ * just go back and repeat. ++ */ ++ task_access_lock_irqsave(p, &lock, &flags); ++ trace_sched_wait_task(p); ++ running = task_running(p); ++ on_rq = p->on_rq; ++ ncsw = 0; ++ if (!match_state || p->state == match_state) ++ ncsw = p->nvcsw | LONG_MIN; /* sets MSB */ ++ task_access_unlock_irqrestore(p, lock, &flags); ++ ++ /* ++ * If it changed from the expected state, bail out now. ++ */ ++ if (unlikely(!ncsw)) ++ break; ++ ++ /* ++ * Was it really running after all now that we ++ * checked with the proper locks actually held? ++ * ++ * Oops. Go back and try again.. ++ */ ++ if (unlikely(running)) { ++ cpu_relax(); ++ continue; ++ } ++ ++ /* ++ * It's not enough that it's not actively running, ++ * it must be off the runqueue _entirely_, and not ++ * preempted! ++ * ++ * So if it was still runnable (but just not actively ++ * running right now), it's preempted, and we should ++ * yield - it could be a while. ++ */ ++ if (unlikely(on_rq)) { ++ ktime_t to = NSEC_PER_SEC / HZ; ++ ++ set_current_state(TASK_UNINTERRUPTIBLE); ++ schedule_hrtimeout(&to, HRTIMER_MODE_REL); ++ continue; ++ } ++ ++ /* ++ * Ahh, all good. It wasn't running, and it wasn't ++ * runnable, which means that it will never become ++ * running in the future either. We're all done! ++ */ ++ break; ++ } ++ ++ return ncsw; ++} ++ ++/*** ++ * kick_process - kick a running thread to enter/exit the kernel ++ * @p: the to-be-kicked thread ++ * ++ * Cause a process which is running on another CPU to enter ++ * kernel-mode, without any delay. (to get signals handled.) ++ * ++ * NOTE: this function doesn't have to take the runqueue lock, ++ * because all it wants to ensure is that the remote task enters ++ * the kernel. If the IPI races and the task has been migrated ++ * to another CPU then no harm is done and the purpose has been ++ * achieved as well. ++ */ ++void kick_process(struct task_struct *p) ++{ ++ int cpu; ++ ++ preempt_disable(); ++ cpu = task_cpu(p); ++ if ((cpu != smp_processor_id()) && task_curr(p)) ++ smp_send_reschedule(cpu); ++ preempt_enable(); ++} ++EXPORT_SYMBOL_GPL(kick_process); ++ ++/* ++ * ->cpus_mask is protected by both rq->lock and p->pi_lock ++ * ++ * A few notes on cpu_active vs cpu_online: ++ * ++ * - cpu_active must be a subset of cpu_online ++ * ++ * - on CPU-up we allow per-CPU kthreads on the online && !active CPU, ++ * see __set_cpus_allowed_ptr(). At this point the newly online ++ * CPU isn't yet part of the sched domains, and balancing will not ++ * see it. ++ * ++ * - on cpu-down we clear cpu_active() to mask the sched domains and ++ * avoid the load balancer to place new tasks on the to be removed ++ * CPU. Existing tasks will remain running there and will be taken ++ * off. ++ * ++ * This means that fallback selection must not select !active CPUs. ++ * And can assume that any active CPU must be online. Conversely ++ * select_task_rq() below may allow selection of !active CPUs in order ++ * to satisfy the above rules. ++ */ ++static int select_fallback_rq(int cpu, struct task_struct *p) ++{ ++ int nid = cpu_to_node(cpu); ++ const struct cpumask *nodemask = NULL; ++ enum { cpuset, possible, fail } state = cpuset; ++ int dest_cpu; ++ ++ /* ++ * If the node that the CPU is on has been offlined, cpu_to_node() ++ * will return -1. There is no CPU on the node, and we should ++ * select the CPU on the other node. ++ */ ++ if (nid != -1) { ++ nodemask = cpumask_of_node(nid); ++ ++ /* Look for allowed, online CPU in same node. */ ++ for_each_cpu(dest_cpu, nodemask) { ++ if (!cpu_active(dest_cpu)) ++ continue; ++ if (cpumask_test_cpu(dest_cpu, &p->cpus_mask)) ++ return dest_cpu; ++ } ++ } ++ ++ for (;;) { ++ /* Any allowed, online CPU? */ ++ for_each_cpu(dest_cpu, &p->cpus_mask) { ++ if (!is_cpu_allowed(p, dest_cpu)) ++ continue; ++ goto out; ++ } ++ ++ /* No more Mr. Nice Guy. */ ++ switch (state) { ++ case cpuset: ++ if (IS_ENABLED(CONFIG_CPUSETS)) { ++ cpuset_cpus_allowed_fallback(p); ++ state = possible; ++ break; ++ } ++ fallthrough; ++ case possible: ++ do_set_cpus_allowed(p, cpu_possible_mask); ++ state = fail; ++ break; ++ ++ case fail: ++ BUG(); ++ break; ++ } ++ } ++ ++out: ++ if (state != cpuset) { ++ /* ++ * Don't tell them about moving exiting tasks or ++ * kernel threads (both mm NULL), since they never ++ * leave kernel. ++ */ ++ if (p->mm && printk_ratelimit()) { ++ printk_deferred("process %d (%s) no longer affine to cpu%d\n", ++ task_pid_nr(p), p->comm, cpu); ++ } ++ } ++ ++ return dest_cpu; ++} ++ ++static inline int best_mask_cpu(int cpu, const cpumask_t *cpumask) ++{ ++ cpumask_t *mask; ++ ++ if (cpumask_test_cpu(cpu, cpumask)) ++ return cpu; ++ ++ mask = &(per_cpu(sched_cpu_affinity_chk_masks, cpu)[0]); ++ while ((cpu = cpumask_any_and(cpumask, mask)) >= nr_cpu_ids) ++ mask++; ++ ++ return cpu; ++} ++ ++/* ++ * task_preemptible_rq - return the rq which the given task can preempt on ++ * @p: task wants to preempt CPU ++ * @only_preempt_low_policy: indicate only preempt rq running low policy than @p ++ */ ++static inline int ++task_preemptible_rq_idle(struct task_struct *p, cpumask_t *chk_mask) ++{ ++ cpumask_t tmp; ++ ++#ifdef CONFIG_SCHED_SMT ++ if (cpumask_and(&tmp, chk_mask, &sched_cpu_sg_idle_mask)) ++ return best_mask_cpu(task_cpu(p), &tmp); ++#endif ++ ++#ifdef CONFIG_SMT_NICE ++ /* Only ttwu on cpu which is not smt supressed */ ++ if (cpumask_andnot(&tmp, chk_mask, &sched_smt_supressed_mask)) { ++ cpumask_t t; ++ if (cpumask_and(&t, &tmp, &sched_rq_queued_masks[SCHED_RQ_EMPTY])) ++ return best_mask_cpu(task_cpu(p), &t); ++ return best_mask_cpu(task_cpu(p), &tmp); ++ } ++#endif ++ ++ if (cpumask_and(&tmp, chk_mask, &sched_rq_queued_masks[SCHED_RQ_EMPTY])) ++ return best_mask_cpu(task_cpu(p), &tmp); ++ return best_mask_cpu(task_cpu(p), chk_mask); ++} ++ ++static inline int ++task_preemptible_rq(struct task_struct *p, cpumask_t *chk_mask, ++ int preempt_level) ++{ ++ cpumask_t tmp; ++ int level; ++ ++#ifdef CONFIG_SCHED_SMT ++#ifdef CONFIG_SMT_NICE ++ if (cpumask_and(&tmp, chk_mask, &sched_cpu_psg_mask)) ++ return best_mask_cpu(task_cpu(p), &tmp); ++#else ++ if (cpumask_and(&tmp, chk_mask, &sched_cpu_sg_idle_mask)) ++ return best_mask_cpu(task_cpu(p), &tmp); ++#endif ++#endif ++ ++ level = find_first_bit(sched_rq_queued_masks_bitmap, ++ NR_SCHED_RQ_QUEUED_LEVEL); ++ ++ while (level < preempt_level) { ++ if (cpumask_and(&tmp, chk_mask, &sched_rq_queued_masks[level])) ++ return best_mask_cpu(task_cpu(p), &tmp); ++ ++ level = find_next_bit(sched_rq_queued_masks_bitmap, ++ NR_SCHED_RQ_QUEUED_LEVEL, ++ level + 1); ++ } ++ ++ if (unlikely(SCHED_RQ_RT == level && ++ level == preempt_level && ++ cpumask_and(&tmp, chk_mask, ++ &sched_rq_queued_masks[SCHED_RQ_RT]))) { ++ unsigned int cpu; ++ ++ for_each_cpu (cpu, &tmp) ++ if (p->prio < sched_rq_prio[cpu]) ++ return cpu; ++ } ++ ++ return best_mask_cpu(task_cpu(p), chk_mask); ++} ++ ++static inline int select_task_rq(struct task_struct *p) ++{ ++ cpumask_t chk_mask; ++ ++ if (unlikely(!cpumask_and(&chk_mask, &p->cpus_mask, cpu_online_mask))) ++ return select_fallback_rq(task_cpu(p), p); ++ ++ /* Check IDLE tasks suitable to run normal priority */ ++ if (idleprio_task(p)) { ++ if (idleprio_suitable(p)) { ++ p->prio = p->normal_prio; ++ update_task_priodl(p); ++ return task_preemptible_rq_idle(p, &chk_mask); ++ } ++ p->prio = NORMAL_PRIO; ++ update_task_priodl(p); ++ } ++ ++ return task_preemptible_rq(p, &chk_mask, ++ task_running_policy_level(p, this_rq())); ++} ++#else /* CONFIG_SMP */ ++static inline int select_task_rq(struct task_struct *p) ++{ ++ return 0; ++} ++#endif /* CONFIG_SMP */ ++ ++static void ++ttwu_stat(struct task_struct *p, int cpu, int wake_flags) ++{ ++ struct rq *rq; ++ ++ if (!schedstat_enabled()) ++ return; ++ ++ rq= this_rq(); ++ ++#ifdef CONFIG_SMP ++ if (cpu == rq->cpu) ++ __schedstat_inc(rq->ttwu_local); ++ else { ++ /** PDS ToDo: ++ * How to do ttwu_wake_remote ++ */ ++ } ++#endif /* CONFIG_SMP */ ++ ++ __schedstat_inc(rq->ttwu_count); ++} ++ ++/* ++ * Mark the task runnable and perform wakeup-preemption. ++ */ ++static inline void ++ttwu_do_wakeup(struct rq *rq, struct task_struct *p, int wake_flags) ++{ ++ p->state = TASK_RUNNING; ++ trace_sched_wakeup(p); ++} ++ ++static inline void ++ttwu_do_activate(struct rq *rq, struct task_struct *p, int wake_flags) ++{ ++#ifdef CONFIG_SMP ++ if (p->sched_contributes_to_load) ++ rq->nr_uninterruptible--; ++#endif ++ ++ activate_task(p, rq); ++ ttwu_do_wakeup(rq, p, 0); ++} ++ ++/* ++ * Consider @p being inside a wait loop: ++ * ++ * for (;;) { ++ * set_current_state(TASK_UNINTERRUPTIBLE); ++ * ++ * if (CONDITION) ++ * break; ++ * ++ * schedule(); ++ * } ++ * __set_current_state(TASK_RUNNING); ++ * ++ * between set_current_state() and schedule(). In this case @p is still ++ * runnable, so all that needs doing is change p->state back to TASK_RUNNING in ++ * an atomic manner. ++ * ++ * By taking task_rq(p)->lock we serialize against schedule(), if @p->on_rq ++ * then schedule() must still happen and p->state can be changed to ++ * TASK_RUNNING. Otherwise we lost the race, schedule() has happened, and we ++ * need to do a full wakeup with enqueue. ++ * ++ * Returns: %true when the wakeup is done, ++ * %false otherwise. ++ */ ++static int ttwu_runnable(struct task_struct *p, int wake_flags) ++{ ++ struct rq *rq; ++ raw_spinlock_t *lock; ++ int ret = 0; ++ ++ rq = __task_access_lock(p, &lock); ++ if (task_on_rq_queued(p)) { ++ ttwu_do_wakeup(rq, p, wake_flags); ++ ret = 1; ++ } ++ __task_access_unlock(p, lock); ++ ++ return ret; ++} ++ ++/* ++ * Notes on Program-Order guarantees on SMP systems. ++ * ++ * MIGRATION ++ * ++ * The basic program-order guarantee on SMP systems is that when a task [t] ++ * migrates, all its activity on its old CPU [c0] happens-before any subsequent ++ * execution on its new CPU [c1]. ++ * ++ * For migration (of runnable tasks) this is provided by the following means: ++ * ++ * A) UNLOCK of the rq(c0)->lock scheduling out task t ++ * B) migration for t is required to synchronize *both* rq(c0)->lock and ++ * rq(c1)->lock (if not at the same time, then in that order). ++ * C) LOCK of the rq(c1)->lock scheduling in task ++ * ++ * Transitivity guarantees that B happens after A and C after B. ++ * Note: we only require RCpc transitivity. ++ * Note: the CPU doing B need not be c0 or c1 ++ * ++ * Example: ++ * ++ * CPU0 CPU1 CPU2 ++ * ++ * LOCK rq(0)->lock ++ * sched-out X ++ * sched-in Y ++ * UNLOCK rq(0)->lock ++ * ++ * LOCK rq(0)->lock // orders against CPU0 ++ * dequeue X ++ * UNLOCK rq(0)->lock ++ * ++ * LOCK rq(1)->lock ++ * enqueue X ++ * UNLOCK rq(1)->lock ++ * ++ * LOCK rq(1)->lock // orders against CPU2 ++ * sched-out Z ++ * sched-in X ++ * UNLOCK rq(1)->lock ++ * ++ * ++ * BLOCKING -- aka. SLEEP + WAKEUP ++ * ++ * For blocking we (obviously) need to provide the same guarantee as for ++ * migration. However the means are completely different as there is no lock ++ * chain to provide order. Instead we do: ++ * ++ * 1) smp_store_release(X->on_cpu, 0) -- finish_task() ++ * 2) smp_cond_load_acquire(!X->on_cpu) -- try_to_wake_up() ++ * ++ * Example: ++ * ++ * CPU0 (schedule) CPU1 (try_to_wake_up) CPU2 (schedule) ++ * ++ * LOCK rq(0)->lock LOCK X->pi_lock ++ * dequeue X ++ * sched-out X ++ * smp_store_release(X->on_cpu, 0); ++ * ++ * smp_cond_load_acquire(&X->on_cpu, !VAL); ++ * X->state = WAKING ++ * set_task_cpu(X,2) ++ * ++ * LOCK rq(2)->lock ++ * enqueue X ++ * X->state = RUNNING ++ * UNLOCK rq(2)->lock ++ * ++ * LOCK rq(2)->lock // orders against CPU1 ++ * sched-out Z ++ * sched-in X ++ * UNLOCK rq(2)->lock ++ * ++ * UNLOCK X->pi_lock ++ * UNLOCK rq(0)->lock ++ * ++ * ++ * However; for wakeups there is a second guarantee we must provide, namely we ++ * must observe the state that lead to our wakeup. That is, not only must our ++ * task observe its own prior state, it must also observe the stores prior to ++ * its wakeup. ++ * ++ * This means that any means of doing remote wakeups must order the CPU doing ++ * the wakeup against the CPU the task is going to end up running on. This, ++ * however, is already required for the regular Program-Order guarantee above, ++ * since the waking CPU is the one issueing the ACQUIRE (smp_cond_load_acquire). ++ * ++ */ ++ ++/** ++ * try_to_wake_up - wake up a thread ++ * @p: the thread to be awakened ++ * @state: the mask of task states that can be woken ++ * @wake_flags: wake modifier flags (WF_*) ++ * ++ * Conceptually does: ++ * ++ * If (@state & @p->state) @p->state = TASK_RUNNING. ++ * ++ * If the task was not queued/runnable, also place it back on a runqueue. ++ * ++ * This function is atomic against schedule() which would dequeue the task. ++ * ++ * It issues a full memory barrier before accessing @p->state, see the comment ++ * with set_current_state(). ++ * ++ * Uses p->pi_lock to serialize against concurrent wake-ups. ++ * ++ * Relies on p->pi_lock stabilizing: ++ * - p->sched_class ++ * - p->cpus_ptr ++ * - p->sched_task_group ++ * in order to do migration, see its use of select_task_rq()/set_task_cpu(). ++ * ++ * Tries really hard to only take one task_rq(p)->lock for performance. ++ * Takes rq->lock in: ++ * - ttwu_runnable() -- old rq, unavoidable, see comment there; ++ * - ttwu_queue() -- new rq, for enqueue of the task; ++ * - psi_ttwu_dequeue() -- much sadness :-( accounting will kill us. ++ * ++ * As a consequence we race really badly with just about everything. See the ++ * many memory barriers and their comments for details. ++ * ++ * Return: %true if @p->state changes (an actual wakeup was done), ++ * %false otherwise. ++ */ ++static int try_to_wake_up(struct task_struct *p, unsigned int state, ++ int wake_flags) ++{ ++ unsigned long flags; ++ struct rq *rq; ++ int cpu, success = 0; ++ ++ /* ++ * If we are going to wake up a thread waiting for CONDITION we ++ * need to ensure that CONDITION=1 done by the caller can not be ++ * reordered with p->state check below. This pairs with smp_store_mb() ++ * in set_current_state() that the waiting thread does. ++ */ ++ raw_spin_lock_irqsave(&p->pi_lock, flags); ++ smp_mb__after_spinlock(); ++ if (!(p->state & state)) ++ goto out; ++ ++ trace_sched_waking(p); ++ ++ /* We're going to change ->state: */ ++ success = 1; ++ cpu = task_cpu(p); ++ ++ /* ++ * Ensure we load p->on_rq _after_ p->state, otherwise it would ++ * be possible to, falsely, observe p->on_rq == 0 and get stuck ++ * in smp_cond_load_acquire() below. ++ * ++ * flush_smp_call_function_from_idle() try_to_wake_up() ++ * STORE p->on_rq = 1 LOAD p->state ++ * UNLOCK rq->lock ++ * ++ * __schedule() (switch to task 'p') ++ * LOCK rq->lock smp_rmb(); ++ * smp_mb__after_spinlock(); ++ * UNLOCK rq->lock ++ * ++ * [task p] ++ * STORE p->state = UNINTERRUPTIBLE LOAD p->on_rq ++ * ++ * Pairs with the LOCK+smp_mb__after_spinlock() on rq->lock in ++ * __schedule(). See the comment for smp_mb__after_spinlock(). ++ */ ++ smp_rmb(); ++ if (p->on_rq && ttwu_runnable(p, wake_flags)) ++ goto stat; ++ ++#ifdef CONFIG_SMP ++ /* ++ * Ensure we load p->on_cpu _after_ p->on_rq, otherwise it would be ++ * possible to, falsely, observe p->on_cpu == 0. ++ * ++ * One must be running (->on_cpu == 1) in order to remove oneself ++ * from the runqueue. ++ * ++ * __schedule() (switch to task 'p') try_to_wake_up() ++ * STORE p->on_cpu = 1 LOAD p->on_rq ++ * UNLOCK rq->lock ++ * ++ * __schedule() (put 'p' to sleep) ++ * LOCK rq->lock smp_rmb(); ++ * smp_mb__after_spinlock(); ++ * STORE p->on_rq = 0 LOAD p->on_cpu ++ * ++ * Pairs with the LOCK+smp_mb__after_spinlock() on rq->lock in ++ * __schedule(). See the comment for smp_mb__after_spinlock(). ++ */ ++ smp_rmb(); ++ ++ /* ++ * If the owning (remote) CPU is still in the middle of schedule() with ++ * this task as prev, wait until its done referencing the task. ++ * ++ * Pairs with the smp_store_release() in finish_task(). ++ * ++ * This ensures that tasks getting woken will be fully ordered against ++ * their previous state and preserve Program Order. ++ */ ++ smp_cond_load_acquire(&p->on_cpu, !VAL); ++ ++ p->sched_contributes_to_load = !!task_contributes_to_load(p); ++ p->state = TASK_WAKING; ++ ++ if (p->in_iowait) { ++ delayacct_blkio_end(p); ++ atomic_dec(&task_rq(p)->nr_iowait); ++ } ++ ++ if (SCHED_ISO == p->policy && ISO_PRIO != p->prio) { ++ p->prio = ISO_PRIO; ++ p->deadline = 0UL; ++ update_task_priodl(p); ++ } ++ ++ cpu = select_task_rq(p); ++ ++ if (cpu != task_cpu(p)) { ++ wake_flags |= WF_MIGRATED; ++ psi_ttwu_dequeue(p); ++ set_task_cpu(p, cpu); ++ } ++#else /* CONFIG_SMP */ ++ if (p->in_iowait) { ++ delayacct_blkio_end(p); ++ atomic_dec(&task_rq(p)->nr_iowait); ++ } ++#endif ++ ++ rq = cpu_rq(cpu); ++ raw_spin_lock(&rq->lock); ++ ++ update_rq_clock(rq); ++ ttwu_do_activate(rq, p, wake_flags); ++ check_preempt_curr(rq, p); ++ ++ raw_spin_unlock(&rq->lock); ++ ++stat: ++ ttwu_stat(p, cpu, wake_flags); ++out: ++ raw_spin_unlock_irqrestore(&p->pi_lock, flags); ++ ++ return success; ++} ++ ++/** ++ * try_invoke_on_locked_down_task - Invoke a function on task in fixed state ++ * @p: Process for which the function is to be invoked. ++ * @func: Function to invoke. ++ * @arg: Argument to function. ++ * ++ * If the specified task can be quickly locked into a definite state ++ * (either sleeping or on a given runqueue), arrange to keep it in that ++ * state while invoking @func(@arg). This function can use ->on_rq and ++ * task_curr() to work out what the state is, if required. Given that ++ * @func can be invoked with a runqueue lock held, it had better be quite ++ * lightweight. ++ * ++ * Returns: ++ * @false if the task slipped out from under the locks. ++ * @true if the task was locked onto a runqueue or is sleeping. ++ * However, @func can override this by returning @false. ++ */ ++bool try_invoke_on_locked_down_task(struct task_struct *p, bool (*func)(struct task_struct *t, void *arg), void *arg) ++{ ++ bool ret = false; ++ struct rq_flags rf; ++ struct rq *rq; ++ ++ lockdep_assert_irqs_enabled(); ++ raw_spin_lock_irq(&p->pi_lock); ++ if (p->on_rq) { ++ rq = __task_rq_lock(p, &rf); ++ if (task_rq(p) == rq) ++ ret = func(p, arg); ++ rq_unlock(rq, &rf); ++ } else { ++ switch (p->state) { ++ case TASK_RUNNING: ++ case TASK_WAKING: ++ break; ++ default: ++ smp_rmb(); // See smp_rmb() comment in try_to_wake_up(). ++ if (!p->on_rq) ++ ret = func(p, arg); ++ } ++ } ++ raw_spin_unlock_irq(&p->pi_lock); ++ return ret; ++} ++ ++/** ++ * wake_up_process - Wake up a specific process ++ * @p: The process to be woken up. ++ * ++ * Attempt to wake up the nominated process and move it to the set of runnable ++ * processes. ++ * ++ * Return: 1 if the process was woken up, 0 if it was already running. ++ * ++ * This function executes a full memory barrier before accessing the task state. ++ */ ++int wake_up_process(struct task_struct *p) ++{ ++ return try_to_wake_up(p, TASK_NORMAL, 0); ++} ++EXPORT_SYMBOL(wake_up_process); ++ ++int wake_up_state(struct task_struct *p, unsigned int state) ++{ ++ return try_to_wake_up(p, state, 0); ++} ++ ++/* ++ * Perform scheduler related setup for a newly forked process p. ++ * p is forked by current. ++ */ ++int sched_fork(unsigned long __maybe_unused clone_flags, struct task_struct *p) ++{ ++ unsigned long flags; ++ int cpu = get_cpu(); ++ struct rq *rq = this_rq(); ++ ++#ifdef CONFIG_PREEMPT_NOTIFIERS ++ INIT_HLIST_HEAD(&p->preempt_notifiers); ++#endif ++ /* Should be reset in fork.c but done here for ease of PDS patching */ ++ p->on_cpu = ++ p->on_rq = ++ p->utime = ++ p->stime = ++ p->sched_time = 0; ++ ++ p->sl_level = pds_skiplist_random_level(p); ++ INIT_SKIPLIST_NODE(&p->sl_node); ++ ++#ifdef CONFIG_COMPACTION ++ p->capture_control = NULL; ++#endif ++ ++ /* ++ * We mark the process as NEW here. This guarantees that ++ * nobody will actually run it, and a signal or other external ++ * event cannot wake it up and insert it on the runqueue either. ++ */ ++ p->state = TASK_NEW; ++ ++ /* ++ * Make sure we do not leak PI boosting priority to the child. ++ */ ++ p->prio = current->normal_prio; ++ ++ /* ++ * Revert to default priority/policy on fork if requested. ++ */ ++ if (unlikely(p->sched_reset_on_fork)) { ++ if (task_has_rt_policy(p)) { ++ p->policy = SCHED_NORMAL; ++ p->static_prio = NICE_TO_PRIO(0); ++ p->rt_priority = 0; ++ } else if (PRIO_TO_NICE(p->static_prio) < 0) ++ p->static_prio = NICE_TO_PRIO(0); ++ ++ p->prio = p->normal_prio = normal_prio(p); ++ ++ /* ++ * We don't need the reset flag anymore after the fork. It has ++ * fulfilled its duty: ++ */ ++ p->sched_reset_on_fork = 0; ++ } ++ ++ /* ++ * Share the timeslice between parent and child, thus the ++ * total amount of pending timeslices in the system doesn't change, ++ * resulting in more scheduling fairness. ++ */ ++ raw_spin_lock_irqsave(&rq->lock, flags); ++ rq->curr->time_slice /= 2; ++ p->time_slice = rq->curr->time_slice; ++#ifdef CONFIG_SCHED_HRTICK ++ hrtick_start(rq, US_TO_NS(rq->curr->time_slice)); ++#endif ++ ++ if (p->time_slice < RESCHED_US) { ++ update_rq_clock(rq); ++ time_slice_expired(p, rq); ++ resched_curr(rq); ++ } else ++ update_task_priodl(p); ++ raw_spin_unlock_irqrestore(&rq->lock, flags); ++ ++ /* ++ * The child is not yet in the pid-hash so no cgroup attach races, ++ * and the cgroup is pinned to this child due to cgroup_fork() ++ * is ran before sched_fork(). ++ * ++ * Silence PROVE_RCU. ++ */ ++ raw_spin_lock_irqsave(&p->pi_lock, flags); ++ /* ++ * We're setting the CPU for the first time, we don't migrate, ++ * so use __set_task_cpu(). ++ */ ++ __set_task_cpu(p, cpu); ++ raw_spin_unlock_irqrestore(&p->pi_lock, flags); ++ ++#ifdef CONFIG_SCHED_INFO ++ if (unlikely(sched_info_on())) ++ memset(&p->sched_info, 0, sizeof(p->sched_info)); ++#endif ++ init_task_preempt_count(p); ++ ++ put_cpu(); ++ return 0; ++} ++ ++void sched_post_fork(struct task_struct *p) {} ++ ++#ifdef CONFIG_SCHEDSTATS ++ ++DEFINE_STATIC_KEY_FALSE(sched_schedstats); ++static bool __initdata __sched_schedstats = false; ++ ++static void set_schedstats(bool enabled) ++{ ++ if (enabled) ++ static_branch_enable(&sched_schedstats); ++ else ++ static_branch_disable(&sched_schedstats); ++} ++ ++void force_schedstat_enabled(void) ++{ ++ if (!schedstat_enabled()) { ++ pr_info("kernel profiling enabled schedstats, disable via kernel.sched_schedstats.\n"); ++ static_branch_enable(&sched_schedstats); ++ } ++} ++ ++static int __init setup_schedstats(char *str) ++{ ++ int ret = 0; ++ if (!str) ++ goto out; ++ ++ /* ++ * This code is called before jump labels have been set up, so we can't ++ * change the static branch directly just yet. Instead set a temporary ++ * variable so init_schedstats() can do it later. ++ */ ++ if (!strcmp(str, "enable")) { ++ __sched_schedstats = true; ++ ret = 1; ++ } else if (!strcmp(str, "disable")) { ++ __sched_schedstats = false; ++ ret = 1; ++ } ++out: ++ if (!ret) ++ pr_warn("Unable to parse schedstats=\n"); ++ ++ return ret; ++} ++__setup("schedstats=", setup_schedstats); ++ ++static void __init init_schedstats(void) ++{ ++ set_schedstats(__sched_schedstats); ++} ++ ++#ifdef CONFIG_PROC_SYSCTL ++int sysctl_schedstats(struct ctl_table *table, int write, ++ void __user *buffer, size_t *lenp, loff_t *ppos) ++{ ++ struct ctl_table t; ++ int err; ++ int state = static_branch_likely(&sched_schedstats); ++ ++ if (write && !capable(CAP_SYS_ADMIN)) ++ return -EPERM; ++ ++ t = *table; ++ t.data = &state; ++ err = proc_dointvec_minmax(&t, write, buffer, lenp, ppos); ++ if (err < 0) ++ return err; ++ if (write) ++ set_schedstats(state); ++ return err; ++} ++#endif /* CONFIG_PROC_SYSCTL */ ++#else /* !CONFIG_SCHEDSTATS */ ++static inline void init_schedstats(void) {} ++#endif /* CONFIG_SCHEDSTATS */ ++ ++/* ++ * wake_up_new_task - wake up a newly created task for the first time. ++ * ++ * This function will do some initial scheduler statistics housekeeping ++ * that must be done for every newly created context, then puts the task ++ * on the runqueue and wakes it. ++ */ ++void wake_up_new_task(struct task_struct *p) ++{ ++ unsigned long flags; ++ struct rq *rq; ++ ++ raw_spin_lock_irqsave(&p->pi_lock, flags); ++ ++ p->state = TASK_RUNNING; ++ ++ rq = cpu_rq(select_task_rq(p)); ++#ifdef CONFIG_SMP ++ /* ++ * Fork balancing, do it here and not earlier because: ++ * - cpus_mask can change in the fork path ++ * - any previously selected CPU might disappear through hotplug ++ * Use __set_task_cpu() to avoid calling sched_class::migrate_task_rq, ++ * as we're not fully set-up yet. ++ */ ++ __set_task_cpu(p, cpu_of(rq)); ++#endif ++ ++ raw_spin_lock(&rq->lock); ++ ++ update_rq_clock(rq); ++ activate_task(p, rq); ++ trace_sched_wakeup_new(p); ++ check_preempt_curr(rq, p); ++ ++ raw_spin_unlock(&rq->lock); ++ raw_spin_unlock_irqrestore(&p->pi_lock, flags); ++} ++ ++#ifdef CONFIG_PREEMPT_NOTIFIERS ++ ++static DEFINE_STATIC_KEY_FALSE(preempt_notifier_key); ++ ++void preempt_notifier_inc(void) ++{ ++ static_branch_inc(&preempt_notifier_key); ++} ++EXPORT_SYMBOL_GPL(preempt_notifier_inc); ++ ++void preempt_notifier_dec(void) ++{ ++ static_branch_dec(&preempt_notifier_key); ++} ++EXPORT_SYMBOL_GPL(preempt_notifier_dec); ++ ++/** ++ * preempt_notifier_register - tell me when current is being preempted & rescheduled ++ * @notifier: notifier struct to register ++ */ ++void preempt_notifier_register(struct preempt_notifier *notifier) ++{ ++ if (!static_branch_unlikely(&preempt_notifier_key)) ++ WARN(1, "registering preempt_notifier while notifiers disabled\n"); ++ ++ hlist_add_head(¬ifier->link, ¤t->preempt_notifiers); ++} ++EXPORT_SYMBOL_GPL(preempt_notifier_register); ++ ++/** ++ * preempt_notifier_unregister - no longer interested in preemption notifications ++ * @notifier: notifier struct to unregister ++ * ++ * This is *not* safe to call from within a preemption notifier. ++ */ ++void preempt_notifier_unregister(struct preempt_notifier *notifier) ++{ ++ hlist_del(¬ifier->link); ++} ++EXPORT_SYMBOL_GPL(preempt_notifier_unregister); ++ ++static void __fire_sched_in_preempt_notifiers(struct task_struct *curr) ++{ ++ struct preempt_notifier *notifier; ++ ++ hlist_for_each_entry(notifier, &curr->preempt_notifiers, link) ++ notifier->ops->sched_in(notifier, raw_smp_processor_id()); ++} ++ ++static __always_inline void fire_sched_in_preempt_notifiers(struct task_struct *curr) ++{ ++ if (static_branch_unlikely(&preempt_notifier_key)) ++ __fire_sched_in_preempt_notifiers(curr); ++} ++ ++static void ++__fire_sched_out_preempt_notifiers(struct task_struct *curr, ++ struct task_struct *next) ++{ ++ struct preempt_notifier *notifier; ++ ++ hlist_for_each_entry(notifier, &curr->preempt_notifiers, link) ++ notifier->ops->sched_out(notifier, next); ++} ++ ++static __always_inline void ++fire_sched_out_preempt_notifiers(struct task_struct *curr, ++ struct task_struct *next) ++{ ++ if (static_branch_unlikely(&preempt_notifier_key)) ++ __fire_sched_out_preempt_notifiers(curr, next); ++} ++ ++#else /* !CONFIG_PREEMPT_NOTIFIERS */ ++ ++static inline void fire_sched_in_preempt_notifiers(struct task_struct *curr) ++{ ++} ++ ++static inline void ++fire_sched_out_preempt_notifiers(struct task_struct *curr, ++ struct task_struct *next) ++{ ++} ++ ++#endif /* CONFIG_PREEMPT_NOTIFIERS */ ++ ++static inline void prepare_task(struct task_struct *next) ++{ ++ /* ++ * Claim the task as running, we do this before switching to it ++ * such that any running task will have this set. ++ * ++ * See the ttwu() WF_ON_CPU case and its ordering comment. ++ */ ++ WRITE_ONCE(next->on_cpu, 1); ++} ++ ++static inline void finish_task(struct task_struct *prev) ++{ ++#ifdef CONFIG_SMP ++ /* ++ * This must be the very last reference to @prev from this CPU. After ++ * p->on_cpu is cleared, the task can be moved to a different CPU. We ++ * must ensure this doesn't happen until the switch is completely ++ * finished. ++ * ++ * In particular, the load of prev->state in finish_task_switch() must ++ * happen before this. ++ * ++ * Pairs with the smp_cond_load_acquire() in try_to_wake_up(). ++ */ ++ smp_store_release(&prev->on_cpu, 0); ++#else ++ prev->on_cpu = 0; ++#endif ++} ++ ++static inline void ++prepare_lock_switch(struct rq *rq, struct task_struct *next) ++{ ++ /* ++ * Since the runqueue lock will be released by the next ++ * task (which is an invalid locking op but in the case ++ * of the scheduler it's an obvious special-case), so we ++ * do an early lockdep release here: ++ */ ++ spin_release(&rq->lock.dep_map, _THIS_IP_); ++#ifdef CONFIG_DEBUG_SPINLOCK ++ /* this is a valid case when another task releases the spinlock */ ++ rq->lock.owner = next; ++#endif ++} ++ ++static inline void finish_lock_switch(struct rq *rq) ++{ ++ /* ++ * If we are tracking spinlock dependencies then we have to ++ * fix up the runqueue lock - which gets 'carried over' from ++ * prev into current: ++ */ ++ spin_acquire(&rq->lock.dep_map, 0, 0, _THIS_IP_); ++ raw_spin_unlock_irq(&rq->lock); ++} ++ ++/** ++ * prepare_task_switch - prepare to switch tasks ++ * @rq: the runqueue preparing to switch ++ * @next: the task we are going to switch to. ++ * ++ * This is called with the rq lock held and interrupts off. It must ++ * be paired with a subsequent finish_task_switch after the context ++ * switch. ++ * ++ * prepare_task_switch sets up locking and calls architecture specific ++ * hooks. ++ */ ++static inline void ++prepare_task_switch(struct rq *rq, struct task_struct *prev, ++ struct task_struct *next) ++{ ++ kcov_prepare_switch(prev); ++ sched_info_switch(rq, prev, next); ++ perf_event_task_sched_out(prev, next); ++ rseq_preempt(prev); ++ fire_sched_out_preempt_notifiers(prev, next); ++ prepare_task(next); ++ prepare_arch_switch(next); ++} ++ ++/** ++ * finish_task_switch - clean up after a task-switch ++ * @rq: runqueue associated with task-switch ++ * @prev: the thread we just switched away from. ++ * ++ * finish_task_switch must be called after the context switch, paired ++ * with a prepare_task_switch call before the context switch. ++ * finish_task_switch will reconcile locking set up by prepare_task_switch, ++ * and do any other architecture-specific cleanup actions. ++ * ++ * Note that we may have delayed dropping an mm in context_switch(). If ++ * so, we finish that here outside of the runqueue lock. (Doing it ++ * with the lock held can cause deadlocks; see schedule() for ++ * details.) ++ * ++ * The context switch have flipped the stack from under us and restored the ++ * local variables which were saved when this task called schedule() in the ++ * past. prev == current is still correct but we need to recalculate this_rq ++ * because prev may have moved to another CPU. ++ */ ++static struct rq *finish_task_switch(struct task_struct *prev) ++ __releases(rq->lock) ++{ ++ struct rq *rq = this_rq(); ++ struct mm_struct *mm = rq->prev_mm; ++ long prev_state; ++ ++ /* ++ * The previous task will have left us with a preempt_count of 2 ++ * because it left us after: ++ * ++ * schedule() ++ * preempt_disable(); // 1 ++ * __schedule() ++ * raw_spin_lock_irq(&rq->lock) // 2 ++ * ++ * Also, see FORK_PREEMPT_COUNT. ++ */ ++ if (WARN_ONCE(preempt_count() != 2*PREEMPT_DISABLE_OFFSET, ++ "corrupted preempt_count: %s/%d/0x%x\n", ++ current->comm, current->pid, preempt_count())) ++ preempt_count_set(FORK_PREEMPT_COUNT); ++ ++ rq->prev_mm = NULL; ++ ++ /* ++ * A task struct has one reference for the use as "current". ++ * If a task dies, then it sets TASK_DEAD in tsk->state and calls ++ * schedule one last time. The schedule call will never return, and ++ * the scheduled task must drop that reference. ++ * ++ * We must observe prev->state before clearing prev->on_cpu (in ++ * finish_task), otherwise a concurrent wakeup can get prev ++ * running on another CPU and we could rave with its RUNNING -> DEAD ++ * transition, resulting in a double drop. ++ */ ++ prev_state = prev->state; ++ vtime_task_switch(prev); ++ perf_event_task_sched_in(prev, current); ++ finish_task(prev); ++ finish_lock_switch(rq); ++ finish_arch_post_lock_switch(); ++ kcov_finish_switch(current); ++ ++ fire_sched_in_preempt_notifiers(current); ++ /* ++ * When switching through a kernel thread, the loop in ++ * membarrier_{private,global}_expedited() may have observed that ++ * kernel thread and not issued an IPI. It is therefore possible to ++ * schedule between user->kernel->user threads without passing though ++ * switch_mm(). Membarrier requires a barrier after storing to ++ * rq->curr, before returning to userspace, so provide them here: ++ * ++ * - a full memory barrier for {PRIVATE,GLOBAL}_EXPEDITED, implicitly ++ * provided by mmdrop(), ++ * - a sync_core for SYNC_CORE. ++ */ ++ if (mm) { ++ membarrier_mm_sync_core_before_usermode(mm); ++ mmdrop(mm); ++ } ++ if (unlikely(prev_state == TASK_DEAD)) { ++ /* ++ * Remove function-return probe instances associated with this ++ * task and put them back on the free list. ++ */ ++ kprobe_flush_task(prev); ++ ++ /* Task is done with its stack. */ ++ put_task_stack(prev); ++ ++ put_task_struct_rcu_user(prev); ++ } ++ ++ tick_nohz_task_switch(); ++ return rq; ++} ++ ++/** ++ * schedule_tail - first thing a freshly forked thread must call. ++ * @prev: the thread we just switched away from. ++ */ ++asmlinkage __visible void schedule_tail(struct task_struct *prev) ++ __releases(rq->lock) ++{ ++ struct rq *rq; ++ ++ /* ++ * New tasks start with FORK_PREEMPT_COUNT, see there and ++ * finish_task_switch() for details. ++ * ++ * finish_task_switch() will drop rq->lock() and lower preempt_count ++ * and the preempt_enable() will end up enabling preemption (on ++ * PREEMPT_COUNT kernels). ++ */ ++ ++ rq = finish_task_switch(prev); ++ preempt_enable(); ++ ++ if (current->set_child_tid) ++ put_user(task_pid_vnr(current), current->set_child_tid); ++ ++ calculate_sigpending(); ++} ++ ++/* ++ * context_switch - switch to the new MM and the new thread's register state. ++ */ ++static __always_inline struct rq * ++context_switch(struct rq *rq, struct task_struct *prev, ++ struct task_struct *next) ++{ ++ prepare_task_switch(rq, prev, next); ++ ++ /* ++ * For paravirt, this is coupled with an exit in switch_to to ++ * combine the page table reload and the switch backend into ++ * one hypercall. ++ */ ++ arch_start_context_switch(prev); ++ ++ /* ++ * kernel -> kernel lazy + transfer active ++ * user -> kernel lazy + mmgrab() active ++ * ++ * kernel -> user switch + mmdrop() active ++ * user -> user switch ++ */ ++ if (!next->mm) { // to kernel ++ enter_lazy_tlb(prev->active_mm, next); ++ ++ next->active_mm = prev->active_mm; ++ if (prev->mm) // from user ++ mmgrab(prev->active_mm); ++ else ++ prev->active_mm = NULL; ++ } else { // to user ++ membarrier_switch_mm(rq, prev->active_mm, next->mm); ++ /* ++ * sys_membarrier() requires an smp_mb() between setting ++ * rq->curr / membarrier_switch_mm() and returning to userspace. ++ * ++ * The below provides this either through switch_mm(), or in ++ * case 'prev->active_mm == next->mm' through ++ * finish_task_switch()'s mmdrop(). ++ */ ++ switch_mm_irqs_off(prev->active_mm, next->mm, next); ++ ++ if (!prev->mm) { // from kernel ++ /* will mmdrop() in finish_task_switch(). */ ++ rq->prev_mm = prev->active_mm; ++ prev->active_mm = NULL; ++ } ++ } ++ ++ prepare_lock_switch(rq, next); ++ ++ /* Here we just switch the register state and the stack. */ ++ switch_to(prev, next, prev); ++ barrier(); ++ ++ return finish_task_switch(prev); ++} ++ ++/* ++ * nr_running, nr_uninterruptible and nr_context_switches: ++ * ++ * externally visible scheduler statistics: current number of runnable ++ * threads, total number of context switches performed since bootup. ++ */ ++unsigned long nr_running(void) ++{ ++ unsigned long i, sum = 0; ++ ++ for_each_online_cpu(i) ++ sum += cpu_rq(i)->nr_running; ++ ++ return sum; ++} ++ ++/* ++ * Check if only the current task is running on the CPU. ++ * ++ * Caution: this function does not check that the caller has disabled ++ * preemption, thus the result might have a time-of-check-to-time-of-use ++ * race. The caller is responsible to use it correctly, for example: ++ * ++ * - from a non-preemptible section (of course) ++ * ++ * - from a thread that is bound to a single CPU ++ * ++ * - in a loop with very short iterations (e.g. a polling loop) ++ */ ++bool single_task_running(void) ++{ ++ return raw_rq()->nr_running == 1; ++} ++EXPORT_SYMBOL(single_task_running); ++ ++unsigned long long nr_context_switches(void) ++{ ++ int i; ++ unsigned long long sum = 0; ++ ++ for_each_possible_cpu(i) ++ sum += cpu_rq(i)->nr_switches; ++ ++ return sum; ++} ++ ++/* ++ * Consumers of these two interfaces, like for example the cpuidle menu ++ * governor, are using nonsensical data. Preferring shallow idle state selection ++ * for a CPU that has IO-wait which might not even end up running the task when ++ * it does become runnable. ++ */ ++ ++unsigned long nr_iowait_cpu(int cpu) ++{ ++ return atomic_read(&cpu_rq(cpu)->nr_iowait); ++} ++ ++/* ++ * IO-wait accounting, and how its mostly bollocks (on SMP). ++ * ++ * The idea behind IO-wait account is to account the idle time that we could ++ * have spend running if it were not for IO. That is, if we were to improve the ++ * storage performance, we'd have a proportional reduction in IO-wait time. ++ * ++ * This all works nicely on UP, where, when a task blocks on IO, we account ++ * idle time as IO-wait, because if the storage were faster, it could've been ++ * running and we'd not be idle. ++ * ++ * This has been extended to SMP, by doing the same for each CPU. This however ++ * is broken. ++ * ++ * Imagine for instance the case where two tasks block on one CPU, only the one ++ * CPU will have IO-wait accounted, while the other has regular idle. Even ++ * though, if the storage were faster, both could've ran at the same time, ++ * utilising both CPUs. ++ * ++ * This means, that when looking globally, the current IO-wait accounting on ++ * SMP is a lower bound, by reason of under accounting. ++ * ++ * Worse, since the numbers are provided per CPU, they are sometimes ++ * interpreted per CPU, and that is nonsensical. A blocked task isn't strictly ++ * associated with any one particular CPU, it can wake to another CPU than it ++ * blocked on. This means the per CPU IO-wait number is meaningless. ++ * ++ * Task CPU affinities can make all that even more 'interesting'. ++ */ ++ ++unsigned long nr_iowait(void) ++{ ++ unsigned long i, sum = 0; ++ ++ for_each_possible_cpu(i) ++ sum += nr_iowait_cpu(i); ++ ++ return sum; ++} ++ ++DEFINE_PER_CPU(struct kernel_stat, kstat); ++DEFINE_PER_CPU(struct kernel_cpustat, kernel_cpustat); ++ ++EXPORT_PER_CPU_SYMBOL(kstat); ++EXPORT_PER_CPU_SYMBOL(kernel_cpustat); ++ ++static inline void pds_update_curr(struct rq *rq, struct task_struct *p) ++{ ++ s64 ns = rq->clock_task - p->last_ran; ++ ++ p->sched_time += ns; ++ account_group_exec_runtime(p, ns); ++ ++ /* time_slice accounting is done in usecs to avoid overflow on 32bit */ ++ p->time_slice -= NS_TO_US(ns); ++ p->last_ran = rq->clock_task; ++} ++ ++/* ++ * Return accounted runtime for the task. ++ * Return separately the current's pending runtime that have not been ++ * accounted yet. ++ */ ++unsigned long long task_sched_runtime(struct task_struct *p) ++{ ++ unsigned long flags; ++ struct rq *rq; ++ raw_spinlock_t *lock; ++ u64 ns; ++ ++#if defined(CONFIG_64BIT) && defined(CONFIG_SMP) ++ /* ++ * 64-bit doesn't need locks to atomically read a 64-bit value. ++ * So we have a optimization chance when the task's delta_exec is 0. ++ * Reading ->on_cpu is racy, but this is ok. ++ * ++ * If we race with it leaving CPU, we'll take a lock. So we're correct. ++ * If we race with it entering CPU, unaccounted time is 0. This is ++ * indistinguishable from the read occurring a few cycles earlier. ++ * If we see ->on_cpu without ->on_rq, the task is leaving, and has ++ * been accounted, so we're correct here as well. ++ */ ++ if (!p->on_cpu || !task_on_rq_queued(p)) ++ return tsk_seruntime(p); ++#endif ++ ++ rq = task_access_lock_irqsave(p, &lock, &flags); ++ /* ++ * Must be ->curr _and_ ->on_rq. If dequeued, we would ++ * project cycles that may never be accounted to this ++ * thread, breaking clock_gettime(). ++ */ ++ if (p == rq->curr && task_on_rq_queued(p)) { ++ update_rq_clock(rq); ++ pds_update_curr(rq, p); ++ } ++ ns = tsk_seruntime(p); ++ task_access_unlock_irqrestore(p, lock, &flags); ++ ++ return ns; ++} ++ ++/* This manages tasks that have run out of timeslice during a scheduler_tick */ ++static inline void pds_scheduler_task_tick(struct rq *rq) ++{ ++ struct task_struct *p = rq->curr; ++ ++ if (is_idle_task(p)) ++ return; ++ ++ pds_update_curr(rq, p); ++ ++ cpufreq_update_util(rq, 0); ++ ++ /* ++ * Tasks that were scheduled in the first half of a tick are not ++ * allowed to run into the 2nd half of the next tick if they will ++ * run out of time slice in the interim. Otherwise, if they have ++ * less than RESCHED_US μs of time slice left they will be rescheduled. ++ */ ++ if (p->time_slice - rq->dither >= RESCHED_US) ++ return; ++ ++ /** ++ * p->time_slice < RESCHED_US. We will modify task_struct under ++ * rq lock as p is rq->curr ++ */ ++ __set_tsk_resched(p); ++} ++ ++#ifdef CONFIG_SMP ++ ++#ifdef CONFIG_SCHED_SMT ++static int active_load_balance_cpu_stop(void *data) ++{ ++ struct rq *rq = this_rq(); ++ struct task_struct *p = data; ++ int cpu; ++ unsigned long flags; ++ ++ local_irq_save(flags); ++ ++ raw_spin_lock(&p->pi_lock); ++ raw_spin_lock(&rq->lock); ++ ++ rq->active_balance = 0; ++ /* ++ * _something_ may have changed the task, double check again ++ */ ++ if (task_on_rq_queued(p) && task_rq(p) == rq && ++ (cpu = cpumask_any_and(&p->cpus_mask, &sched_cpu_sg_idle_mask)) < nr_cpu_ids) ++ rq = __migrate_task(rq, p, cpu); ++ ++ raw_spin_unlock(&rq->lock); ++ raw_spin_unlock(&p->pi_lock); ++ ++ local_irq_restore(flags); ++ ++ return 0; ++} ++ ++/* pds_sg_balance_trigger - trigger slibing group balance for @cpu */ ++static void pds_sg_balance_trigger(const int cpu) ++{ ++ struct rq *rq = cpu_rq(cpu); ++ unsigned long flags; ++ struct task_struct *curr; ++ ++ if (!raw_spin_trylock_irqsave(&rq->lock, flags)) ++ return; ++ curr = rq->curr; ++ if (!is_idle_task(curr) && ++ cpumask_intersects(&curr->cpus_mask, &sched_cpu_sg_idle_mask)) { ++ int active_balance = 0; ++ ++ if (likely(!rq->active_balance)) { ++ rq->active_balance = 1; ++ active_balance = 1; ++ } ++ ++ raw_spin_unlock_irqrestore(&rq->lock, flags); ++ ++ if (likely(active_balance)) ++ stop_one_cpu_nowait(cpu, active_load_balance_cpu_stop, ++ curr, &rq->active_balance_work); ++ } else ++ raw_spin_unlock_irqrestore(&rq->lock, flags); ++} ++ ++/* ++ * pds_sg_balance_check - slibing group balance check for run queue @rq ++ */ ++static inline void pds_sg_balance_check(const struct rq *rq) ++{ ++ cpumask_t chk; ++ int i; ++ ++ /* Only online cpu will do sg balance checking */ ++ if (unlikely(!rq->online)) ++ return; ++ ++ /* Only cpu in slibing idle group will do the checking */ ++ if (!cpumask_test_cpu(cpu_of(rq), &sched_cpu_sg_idle_mask)) ++ return; ++ ++ /* Find potential cpus which can migrate the currently running task */ ++ if (!cpumask_andnot(&chk, &sched_rq_pending_masks[SCHED_RQ_EMPTY], ++ &sched_rq_queued_masks[SCHED_RQ_EMPTY])) ++ return; ++ ++ for_each_cpu(i, &chk) { ++ /* skip the cpu which has idle slibing cpu */ ++ if (cpumask_test_cpu(per_cpu(sched_sibling_cpu, i), ++ &sched_rq_queued_masks[SCHED_RQ_EMPTY])) ++ continue; ++ pds_sg_balance_trigger(i); ++ } ++} ++ ++#endif /* CONFIG_SCHED_SMT */ ++#endif /* CONFIG_SMP */ ++ ++/* ++ * This function gets called by the timer code, with HZ frequency. ++ * We call it with interrupts disabled. ++ */ ++void scheduler_tick(void) ++{ ++ int cpu __maybe_unused = smp_processor_id(); ++ struct rq *rq = cpu_rq(cpu); ++ ++ arch_scale_freq_tick(); ++ sched_clock_tick(); ++ ++ raw_spin_lock(&rq->lock); ++ update_rq_clock(rq); ++ ++ pds_scheduler_task_tick(rq); ++ update_sched_rq_queued_masks_normal(rq); ++ calc_global_load_tick(rq); ++ psi_task_tick(rq); ++ ++ rq->last_tick = rq->clock; ++ raw_spin_unlock(&rq->lock); ++ ++ perf_event_task_tick(); ++} ++ ++#ifdef CONFIG_NO_HZ_FULL ++struct tick_work { ++ int cpu; ++ atomic_t state; ++ struct delayed_work work; ++}; ++/* Values for ->state, see diagram below. */ ++#define TICK_SCHED_REMOTE_OFFLINE 0 ++#define TICK_SCHED_REMOTE_OFFLINING 1 ++#define TICK_SCHED_REMOTE_RUNNING 2 ++ ++/* ++ * State diagram for ->state: ++ * ++ * ++ * TICK_SCHED_REMOTE_OFFLINE ++ * | ^ ++ * | | ++ * | | sched_tick_remote() ++ * | | ++ * | | ++ * +--TICK_SCHED_REMOTE_OFFLINING ++ * | ^ ++ * | | ++ * sched_tick_start() | | sched_tick_stop() ++ * | | ++ * V | ++ * TICK_SCHED_REMOTE_RUNNING ++ * ++ * ++ * Other transitions get WARN_ON_ONCE(), except that sched_tick_remote() ++ * and sched_tick_start() are happy to leave the state in RUNNING. ++ */ ++ ++static struct tick_work __percpu *tick_work_cpu; ++ ++static void sched_tick_remote(struct work_struct *work) ++{ ++ struct delayed_work *dwork = to_delayed_work(work); ++ struct tick_work *twork = container_of(dwork, struct tick_work, work); ++ int cpu = twork->cpu; ++ struct rq *rq = cpu_rq(cpu); ++ struct task_struct *curr; ++ unsigned long flags; ++ u64 delta; ++ int os; ++ ++ /* ++ * Handle the tick only if it appears the remote CPU is running in full ++ * dynticks mode. The check is racy by nature, but missing a tick or ++ * having one too much is no big deal because the scheduler tick updates ++ * statistics and checks timeslices in a time-independent way, regardless ++ * of when exactly it is running. ++ */ ++ if (!tick_nohz_tick_stopped_cpu(cpu)) ++ goto out_requeue; ++ ++ raw_spin_lock_irqsave(&rq->lock, flags); ++ curr = rq->curr; ++ if (cpu_is_offline(cpu)) ++ goto out_unlock; ++ ++ update_rq_clock(rq); ++ if (!is_idle_task(curr)) { ++ /* ++ * Make sure the next tick runs within a reasonable ++ * amount of time. ++ */ ++ delta = rq_clock_task(rq) - curr->last_ran; ++ WARN_ON_ONCE(delta > (u64)NSEC_PER_SEC * 3); ++ } ++ pds_scheduler_task_tick(rq); ++ update_sched_rq_queued_masks_normal(rq); ++ calc_load_nohz_remote(rq); ++ ++out_unlock: ++ raw_spin_unlock_irqrestore(&rq->lock, flags); ++ ++out_requeue: ++ /* ++ * Run the remote tick once per second (1Hz). This arbitrary ++ * frequency is large enough to avoid overload but short enough ++ * to keep scheduler internal stats reasonably up to date. But ++ * first update state to reflect hotplug activity if required. ++ */ ++ os = atomic_fetch_add_unless(&twork->state, -1, TICK_SCHED_REMOTE_RUNNING); ++ WARN_ON_ONCE(os == TICK_SCHED_REMOTE_OFFLINE); ++ if (os == TICK_SCHED_REMOTE_RUNNING) ++ queue_delayed_work(system_unbound_wq, dwork, HZ); ++} ++ ++static void sched_tick_start(int cpu) ++{ ++ int os; ++ struct tick_work *twork; ++ ++ if (housekeeping_cpu(cpu, HK_FLAG_TICK)) ++ return; ++ ++ WARN_ON_ONCE(!tick_work_cpu); ++ ++ twork = per_cpu_ptr(tick_work_cpu, cpu); ++ os = atomic_xchg(&twork->state, TICK_SCHED_REMOTE_RUNNING); ++ WARN_ON_ONCE(os == TICK_SCHED_REMOTE_RUNNING); ++ if (os == TICK_SCHED_REMOTE_OFFLINE) { ++ twork->cpu = cpu; ++ INIT_DELAYED_WORK(&twork->work, sched_tick_remote); ++ queue_delayed_work(system_unbound_wq, &twork->work, HZ); ++ } ++} ++ ++#ifdef CONFIG_HOTPLUG_CPU ++static void sched_tick_stop(int cpu) ++{ ++ struct tick_work *twork; ++ ++ if (housekeeping_cpu(cpu, HK_FLAG_TICK)) ++ return; ++ ++ WARN_ON_ONCE(!tick_work_cpu); ++ ++ twork = per_cpu_ptr(tick_work_cpu, cpu); ++ cancel_delayed_work_sync(&twork->work); ++} ++#endif /* CONFIG_HOTPLUG_CPU */ ++ ++int __init sched_tick_offload_init(void) ++{ ++ tick_work_cpu = alloc_percpu(struct tick_work); ++ BUG_ON(!tick_work_cpu); ++ return 0; ++} ++ ++#else /* !CONFIG_NO_HZ_FULL */ ++static inline void sched_tick_start(int cpu) { } ++static inline void sched_tick_stop(int cpu) { } ++#endif ++ ++#if defined(CONFIG_PREEMPTION) && (defined(CONFIG_DEBUG_PREEMPT) || \ ++ defined(CONFIG_PREEMPT_TRACER)) ++/* ++ * If the value passed in is equal to the current preempt count ++ * then we just disabled preemption. Start timing the latency. ++ */ ++static inline void preempt_latency_start(int val) ++{ ++ if (preempt_count() == val) { ++ unsigned long ip = get_lock_parent_ip(); ++#ifdef CONFIG_DEBUG_PREEMPT ++ current->preempt_disable_ip = ip; ++#endif ++ trace_preempt_off(CALLER_ADDR0, ip); ++ } ++} ++ ++void preempt_count_add(int val) ++{ ++#ifdef CONFIG_DEBUG_PREEMPT ++ /* ++ * Underflow? ++ */ ++ if (DEBUG_LOCKS_WARN_ON((preempt_count() < 0))) ++ return; ++#endif ++ __preempt_count_add(val); ++#ifdef CONFIG_DEBUG_PREEMPT ++ /* ++ * Spinlock count overflowing soon? ++ */ ++ DEBUG_LOCKS_WARN_ON((preempt_count() & PREEMPT_MASK) >= ++ PREEMPT_MASK - 10); ++#endif ++ preempt_latency_start(val); ++} ++EXPORT_SYMBOL(preempt_count_add); ++NOKPROBE_SYMBOL(preempt_count_add); ++ ++/* ++ * If the value passed in equals to the current preempt count ++ * then we just enabled preemption. Stop timing the latency. ++ */ ++static inline void preempt_latency_stop(int val) ++{ ++ if (preempt_count() == val) ++ trace_preempt_on(CALLER_ADDR0, get_lock_parent_ip()); ++} ++ ++void preempt_count_sub(int val) ++{ ++#ifdef CONFIG_DEBUG_PREEMPT ++ /* ++ * Underflow? ++ */ ++ if (DEBUG_LOCKS_WARN_ON(val > preempt_count())) ++ return; ++ /* ++ * Is the spinlock portion underflowing? ++ */ ++ if (DEBUG_LOCKS_WARN_ON((val < PREEMPT_MASK) && ++ !(preempt_count() & PREEMPT_MASK))) ++ return; ++#endif ++ ++ preempt_latency_stop(val); ++ __preempt_count_sub(val); ++} ++EXPORT_SYMBOL(preempt_count_sub); ++NOKPROBE_SYMBOL(preempt_count_sub); ++ ++#else ++static inline void preempt_latency_start(int val) { } ++static inline void preempt_latency_stop(int val) { } ++#endif ++ ++/* ++ * Timeslices below RESCHED_US are considered as good as expired as there's no ++ * point rescheduling when there's so little time left. SCHED_BATCH tasks ++ * have been flagged be not latency sensitive and likely to be fully CPU ++ * bound so every time they're rescheduled they have their time_slice ++ * refilled, but get a new later deadline to have little effect on ++ * SCHED_NORMAL tasks. ++ ++ */ ++static inline void check_deadline(struct task_struct *p, struct rq *rq) ++{ ++ if (rq->idle == p) ++ return; ++ ++ pds_update_curr(rq, p); ++ ++ if (p->time_slice < RESCHED_US) { ++ time_slice_expired(p, rq); ++ if (SCHED_ISO == p->policy && ISO_PRIO == p->prio) { ++ p->prio = NORMAL_PRIO; ++ p->deadline = rq->clock + task_deadline_diff(p); ++ update_task_priodl(p); ++ } ++ if (SCHED_FIFO != p->policy && task_on_rq_queued(p)) ++ requeue_task(p, rq); ++ } ++} ++ ++#ifdef CONFIG_SMP ++ ++#define SCHED_RQ_NR_MIGRATION (32UL) ++/* ++ * Migrate pending tasks in @rq to @dest_cpu ++ * Will try to migrate mininal of half of @rq nr_running tasks and ++ * SCHED_RQ_NR_MIGRATION to @dest_cpu ++ */ ++static inline int ++migrate_pending_tasks(struct rq *rq, struct rq *dest_rq, int filter_prio) ++{ ++ struct task_struct *p; ++ int dest_cpu = cpu_of(dest_rq); ++ int nr_migrated = 0; ++ int nr_tries = min((rq->nr_running + 1) / 2, SCHED_RQ_NR_MIGRATION); ++ struct skiplist_node *node = rq->sl_header.next[0]; ++ ++ while (nr_tries && node != &rq->sl_header) { ++ p = skiplist_entry(node, struct task_struct, sl_node); ++ node = node->next[0]; ++ ++ if (task_running(p)) ++ continue; ++ if (p->prio >= filter_prio) ++ break; ++ if (cpumask_test_cpu(dest_cpu, &p->cpus_mask)) { ++ dequeue_task(p, rq, 0); ++ set_task_cpu(p, dest_cpu); ++ enqueue_task(p, dest_rq, 0); ++ nr_migrated++; ++ } ++ nr_tries--; ++ /* make a jump */ ++ if (node == &rq->sl_header) ++ break; ++ node = node->next[0]; ++ } ++ ++ return nr_migrated; ++} ++ ++static inline int ++take_queued_task_cpumask(struct rq *rq, cpumask_t *chk_mask, int filter_prio) ++{ ++ int src_cpu; ++ ++ for_each_cpu(src_cpu, chk_mask) { ++ int nr_migrated; ++ struct rq *src_rq = cpu_rq(src_cpu); ++ ++ if (!do_raw_spin_trylock(&src_rq->lock)) { ++ if (PRIO_LIMIT == filter_prio) ++ continue; ++ return 0; ++ } ++ spin_acquire(&src_rq->lock.dep_map, SINGLE_DEPTH_NESTING, 1, _RET_IP_); ++ ++ update_rq_clock(src_rq); ++ if ((nr_migrated = migrate_pending_tasks(src_rq, rq, filter_prio))) ++ cpufreq_update_this_cpu(rq, 0); ++ ++ spin_release(&src_rq->lock.dep_map, _RET_IP_); ++ do_raw_spin_unlock(&src_rq->lock); ++ ++ if (nr_migrated || PRIO_LIMIT != filter_prio) ++ return nr_migrated; ++ } ++ return 0; ++} ++ ++static inline int take_other_rq_task(struct rq *rq, int cpu, int filter_prio) ++{ ++ struct cpumask *affinity_mask, *end; ++ struct cpumask chk; ++ ++ if (PRIO_LIMIT == filter_prio) { ++ cpumask_complement(&chk, &sched_rq_pending_masks[SCHED_RQ_EMPTY]); ++#ifdef CONFIG_SMT_NICE ++ { ++ /* also try to take IDLE priority tasks from smt supressed cpu */ ++ struct cpumask t; ++ if (cpumask_and(&t, &sched_smt_supressed_mask, ++ &sched_rq_queued_masks[SCHED_RQ_IDLE])) ++ cpumask_or(&chk, &chk, &t); ++ } ++#endif ++ } else if (NORMAL_PRIO == filter_prio) { ++ cpumask_or(&chk, &sched_rq_pending_masks[SCHED_RQ_RT], ++ &sched_rq_pending_masks[SCHED_RQ_ISO]); ++ } else if (IDLE_PRIO == filter_prio) { ++ cpumask_complement(&chk, &sched_rq_pending_masks[SCHED_RQ_EMPTY]); ++ cpumask_andnot(&chk, &chk, &sched_rq_pending_masks[SCHED_RQ_IDLE]); ++ } else ++ cpumask_copy(&chk, &sched_rq_pending_masks[SCHED_RQ_RT]); ++ ++ if (cpumask_empty(&chk)) ++ return 0; ++ ++ affinity_mask = per_cpu(sched_cpu_llc_start_mask, cpu); ++ end = per_cpu(sched_cpu_affinity_chk_end_masks, cpu); ++ do { ++ struct cpumask tmp; ++ ++ if (cpumask_and(&tmp, &chk, affinity_mask) && ++ take_queued_task_cpumask(rq, &tmp, filter_prio)) ++ return 1; ++ } while (++affinity_mask < end); ++ ++ return 0; ++} ++#endif ++ ++static inline struct task_struct * ++choose_next_task(struct rq *rq, int cpu, struct task_struct *prev) ++{ ++ struct task_struct *next = rq_first_queued_task(rq); ++ ++#ifdef CONFIG_SMT_NICE ++ if (cpumask_test_cpu(cpu, &sched_smt_supressed_mask)) { ++ if (next->prio >= IDLE_PRIO) { ++ if (rq->online && ++ take_other_rq_task(rq, cpu, IDLE_PRIO)) ++ return rq_first_queued_task(rq); ++ return rq->idle; ++ } ++ } ++#endif ++ ++#ifdef CONFIG_SMP ++ if (likely(rq->online)) ++ if (take_other_rq_task(rq, cpu, next->prio)) { ++ resched_curr(rq); ++ return rq_first_queued_task(rq); ++ } ++#endif ++ return next; ++} ++ ++static inline unsigned long get_preempt_disable_ip(struct task_struct *p) ++{ ++#ifdef CONFIG_DEBUG_PREEMPT ++ return p->preempt_disable_ip; ++#else ++ return 0; ++#endif ++} ++ ++/* ++ * Print scheduling while atomic bug: ++ */ ++static noinline void __schedule_bug(struct task_struct *prev) ++{ ++ /* Save this before calling printk(), since that will clobber it */ ++ unsigned long preempt_disable_ip = get_preempt_disable_ip(current); ++ ++ if (oops_in_progress) ++ return; ++ ++ printk(KERN_ERR "BUG: scheduling while atomic: %s/%d/0x%08x\n", ++ prev->comm, prev->pid, preempt_count()); ++ ++ debug_show_held_locks(prev); ++ print_modules(); ++ if (irqs_disabled()) ++ print_irqtrace_events(prev); ++ if (IS_ENABLED(CONFIG_DEBUG_PREEMPT) ++ && in_atomic_preempt_off()) { ++ pr_err("Preemption disabled at:"); ++ print_ip_sym(KERN_ERR, preempt_disable_ip); ++ } ++ if (panic_on_warn) ++ panic("scheduling while atomic\n"); ++ ++ dump_stack(); ++ add_taint(TAINT_WARN, LOCKDEP_STILL_OK); ++} ++ ++/* ++ * Various schedule()-time debugging checks and statistics: ++ */ ++static inline void schedule_debug(struct task_struct *prev, bool preempt) ++{ ++#ifdef CONFIG_SCHED_STACK_END_CHECK ++ if (task_stack_end_corrupted(prev)) ++ panic("corrupted stack end detected inside scheduler\n"); ++#endif ++ ++#ifdef CONFIG_DEBUG_ATOMIC_SLEEP ++ if (!preempt && prev->state && prev->non_block_count) { ++ printk(KERN_ERR "BUG: scheduling in a non-blocking section: %s/%d/%i\n", ++ prev->comm, prev->pid, prev->non_block_count); ++ dump_stack(); ++ add_taint(TAINT_WARN, LOCKDEP_STILL_OK); ++ } ++#endif ++ ++ if (unlikely(in_atomic_preempt_off())) { ++ __schedule_bug(prev); ++ preempt_count_set(PREEMPT_DISABLED); ++ } ++ rcu_sleep_check(); ++ ++ profile_hit(SCHED_PROFILING, __builtin_return_address(0)); ++ ++ schedstat_inc(this_rq()->sched_count); ++} ++ ++static inline void set_rq_task(struct rq *rq, struct task_struct *p) ++{ ++ p->last_ran = rq->clock_task; ++ ++#ifdef CONFIG_HIGH_RES_TIMERS ++ if (p != rq->idle) ++ hrtick_start(rq, US_TO_NS(p->time_slice)); ++#endif ++ /* update rq->dither */ ++ rq->dither = rq_dither(rq); ++} ++ ++/* ++ * schedule() is the main scheduler function. ++ * ++ * The main means of driving the scheduler and thus entering this function are: ++ * ++ * 1. Explicit blocking: mutex, semaphore, waitqueue, etc. ++ * ++ * 2. TIF_NEED_RESCHED flag is checked on interrupt and userspace return ++ * paths. For example, see arch/x86/entry_64.S. ++ * ++ * To drive preemption between tasks, the scheduler sets the flag in timer ++ * interrupt handler scheduler_tick(). ++ * ++ * 3. Wakeups don't really cause entry into schedule(). They add a ++ * task to the run-queue and that's it. ++ * ++ * Now, if the new task added to the run-queue preempts the current ++ * task, then the wakeup sets TIF_NEED_RESCHED and schedule() gets ++ * called on the nearest possible occasion: ++ * ++ * - If the kernel is preemptible (CONFIG_PREEMPTION=y): ++ * ++ * - in syscall or exception context, at the next outmost ++ * preempt_enable(). (this might be as soon as the wake_up()'s ++ * spin_unlock()!) ++ * ++ * - in IRQ context, return from interrupt-handler to ++ * preemptible context ++ * ++ * - If the kernel is not preemptible (CONFIG_PREEMPT is not set) ++ * then at the next: ++ * ++ * - cond_resched() call ++ * - explicit schedule() call ++ * - return from syscall or exception to user-space ++ * - return from interrupt-handler to user-space ++ * ++ * WARNING: must be called with preemption disabled! ++ */ ++static void __sched notrace __schedule(bool preempt) ++{ ++ struct task_struct *prev, *next; ++ unsigned long *switch_count; ++ struct rq *rq; ++ int cpu; ++ ++ cpu = smp_processor_id(); ++ rq = cpu_rq(cpu); ++ prev = rq->curr; ++ ++ schedule_debug(prev, preempt); ++ ++ /* by passing sched_feat(HRTICK) checking which PDS doesn't support */ ++ hrtick_clear(rq); ++ ++ local_irq_disable(); ++ rcu_note_context_switch(preempt); ++ ++ /* ++ * Make sure that signal_pending_state()->signal_pending() below ++ * can't be reordered with __set_current_state(TASK_INTERRUPTIBLE) ++ * done by the caller to avoid the race with signal_wake_up(). ++ * ++ * The membarrier system call requires a full memory barrier ++ * after coming from user-space, before storing to rq->curr. ++ */ ++ raw_spin_lock(&rq->lock); ++ smp_mb__after_spinlock(); ++ ++ update_rq_clock(rq); ++ ++ switch_count = &prev->nivcsw; ++ if (!preempt && prev->state) { ++ if (signal_pending_state(prev->state, prev)) { ++ prev->state = TASK_RUNNING; ++ } else { ++ deactivate_task(prev, rq); ++ ++ if (prev->in_iowait) { ++ atomic_inc(&rq->nr_iowait); ++ delayacct_blkio_start(); ++ } ++ } ++ switch_count = &prev->nvcsw; ++ } ++ ++ check_deadline(prev, rq); ++ ++ next = choose_next_task(rq, cpu, prev); ++ clear_tsk_need_resched(prev); ++ clear_preempt_need_resched(); ++ ++ set_rq_task(rq, next); ++ ++ if (prev != next) { ++ if (next->prio == PRIO_LIMIT) ++ schedstat_inc(rq->sched_goidle); ++ ++ /* ++ * RCU users of rcu_dereference(rq->curr) may not see ++ * changes to task_struct made by pick_next_task(). ++ */ ++ RCU_INIT_POINTER(rq->curr, next); ++ /* ++ * The membarrier system call requires each architecture ++ * to have a full memory barrier after updating ++ * rq->curr, before returning to user-space. ++ * ++ * Here are the schemes providing that barrier on the ++ * various architectures: ++ * - mm ? switch_mm() : mmdrop() for x86, s390, sparc, PowerPC. ++ * switch_mm() rely on membarrier_arch_switch_mm() on PowerPC. ++ * - finish_lock_switch() for weakly-ordered ++ * architectures where spin_unlock is a full barrier, ++ * - switch_to() for arm64 (weakly-ordered, spin_unlock ++ * is a RELEASE barrier), ++ */ ++ ++*switch_count; ++ rq->nr_switches++; ++ ++ psi_sched_switch(prev, next, !task_on_rq_queued(prev)); ++ ++ trace_sched_switch(preempt, prev, next); ++ ++ /* Also unlocks the rq: */ ++ rq = context_switch(rq, prev, next); ++#ifdef CONFIG_SCHED_SMT ++ pds_sg_balance_check(rq); ++#endif ++ } else ++ raw_spin_unlock_irq(&rq->lock); ++} ++ ++void __noreturn do_task_dead(void) ++{ ++ /* Causes final put_task_struct in finish_task_switch(): */ ++ set_special_state(TASK_DEAD); ++ ++ /* Tell freezer to ignore us: */ ++ current->flags |= PF_NOFREEZE; ++ __schedule(false); ++ ++ BUG(); ++ ++ /* Avoid "noreturn function does return" - but don't continue if BUG() is a NOP: */ ++ for (;;) ++ cpu_relax(); ++} ++ ++static inline void sched_submit_work(struct task_struct *tsk) ++{ ++ if (!tsk->state || tsk_is_pi_blocked(tsk) || ++ signal_pending_state(tsk->state, tsk)) ++ return; ++ ++ /* ++ * If a worker went to sleep, notify and ask workqueue whether ++ * it wants to wake up a task to maintain concurrency. ++ * As this function is called inside the schedule() context, ++ * we disable preemption to avoid it calling schedule() again ++ * in the possible wakeup of a kworker. ++ */ ++ if (tsk->flags & (PF_WQ_WORKER | PF_IO_WORKER)) { ++ preempt_disable(); ++ if (tsk->flags & PF_WQ_WORKER) ++ wq_worker_sleeping(tsk); ++ else ++ io_wq_worker_sleeping(tsk); ++ preempt_enable_no_resched(); ++ } ++ ++ /* ++ * If we are going to sleep and we have plugged IO queued, ++ * make sure to submit it to avoid deadlocks. ++ */ ++ if (blk_needs_flush_plug(tsk)) ++ blk_schedule_flush_plug(tsk); ++} ++ ++static void sched_update_worker(struct task_struct *tsk) ++{ ++ if (tsk->flags & (PF_WQ_WORKER | PF_IO_WORKER)) { ++ if (tsk->flags & PF_WQ_WORKER) ++ wq_worker_running(tsk); ++ else ++ io_wq_worker_running(tsk); ++ } ++} ++ ++asmlinkage __visible void __sched schedule(void) ++{ ++ struct task_struct *tsk = current; ++ ++ sched_submit_work(tsk); ++ do { ++ preempt_disable(); ++ __schedule(false); ++ sched_preempt_enable_no_resched(); ++ } while (need_resched()); ++ sched_update_worker(tsk); ++} ++EXPORT_SYMBOL(schedule); ++ ++/* ++ * synchronize_rcu_tasks() makes sure that no task is stuck in preempted ++ * state (have scheduled out non-voluntarily) by making sure that all ++ * tasks have either left the run queue or have gone into user space. ++ * As idle tasks do not do either, they must not ever be preempted ++ * (schedule out non-voluntarily). ++ * ++ * schedule_idle() is similar to schedule_preempt_disable() except that it ++ * never enables preemption because it does not call sched_submit_work(). ++ */ ++void __sched schedule_idle(void) ++{ ++ /* ++ * As this skips calling sched_submit_work(), which the idle task does ++ * regardless because that function is a nop when the task is in a ++ * TASK_RUNNING state, make sure this isn't used someplace that the ++ * current task can be in any other state. Note, idle is always in the ++ * TASK_RUNNING state. ++ */ ++ WARN_ON_ONCE(current->state); ++ do { ++ __schedule(false); ++ } while (need_resched()); ++} ++ ++#ifdef CONFIG_CONTEXT_TRACKING ++asmlinkage __visible void __sched schedule_user(void) ++{ ++ /* ++ * If we come here after a random call to set_need_resched(), ++ * or we have been woken up remotely but the IPI has not yet arrived, ++ * we haven't yet exited the RCU idle mode. Do it here manually until ++ * we find a better solution. ++ * ++ * NB: There are buggy callers of this function. Ideally we ++ * should warn if prev_state != CONTEXT_USER, but that will trigger ++ * too frequently to make sense yet. ++ */ ++ enum ctx_state prev_state = exception_enter(); ++ schedule(); ++ exception_exit(prev_state); ++} ++#endif ++ ++/** ++ * schedule_preempt_disabled - called with preemption disabled ++ * ++ * Returns with preemption disabled. Note: preempt_count must be 1 ++ */ ++void __sched schedule_preempt_disabled(void) ++{ ++ sched_preempt_enable_no_resched(); ++ schedule(); ++ preempt_disable(); ++} ++ ++static void __sched notrace preempt_schedule_common(void) ++{ ++ do { ++ /* ++ * Because the function tracer can trace preempt_count_sub() ++ * and it also uses preempt_enable/disable_notrace(), if ++ * NEED_RESCHED is set, the preempt_enable_notrace() called ++ * by the function tracer will call this function again and ++ * cause infinite recursion. ++ * ++ * Preemption must be disabled here before the function ++ * tracer can trace. Break up preempt_disable() into two ++ * calls. One to disable preemption without fear of being ++ * traced. The other to still record the preemption latency, ++ * which can also be traced by the function tracer. ++ */ ++ preempt_disable_notrace(); ++ preempt_latency_start(1); ++ __schedule(true); ++ preempt_latency_stop(1); ++ preempt_enable_no_resched_notrace(); ++ ++ /* ++ * Check again in case we missed a preemption opportunity ++ * between schedule and now. ++ */ ++ } while (need_resched()); ++} ++ ++#ifdef CONFIG_PREEMPTION ++/* ++ * This is the entry point to schedule() from in-kernel preemption ++ * off of preempt_enable. ++ */ ++asmlinkage __visible void __sched notrace preempt_schedule(void) ++{ ++ /* ++ * If there is a non-zero preempt_count or interrupts are disabled, ++ * we do not want to preempt the current task. Just return.. ++ */ ++ if (likely(!preemptible())) ++ return; ++ ++ preempt_schedule_common(); ++} ++NOKPROBE_SYMBOL(preempt_schedule); ++EXPORT_SYMBOL(preempt_schedule); ++ ++/** ++ * preempt_schedule_notrace - preempt_schedule called by tracing ++ * ++ * The tracing infrastructure uses preempt_enable_notrace to prevent ++ * recursion and tracing preempt enabling caused by the tracing ++ * infrastructure itself. But as tracing can happen in areas coming ++ * from userspace or just about to enter userspace, a preempt enable ++ * can occur before user_exit() is called. This will cause the scheduler ++ * to be called when the system is still in usermode. ++ * ++ * To prevent this, the preempt_enable_notrace will use this function ++ * instead of preempt_schedule() to exit user context if needed before ++ * calling the scheduler. ++ */ ++asmlinkage __visible void __sched notrace preempt_schedule_notrace(void) ++{ ++ enum ctx_state prev_ctx; ++ ++ if (likely(!preemptible())) ++ return; ++ ++ do { ++ /* ++ * Because the function tracer can trace preempt_count_sub() ++ * and it also uses preempt_enable/disable_notrace(), if ++ * NEED_RESCHED is set, the preempt_enable_notrace() called ++ * by the function tracer will call this function again and ++ * cause infinite recursion. ++ * ++ * Preemption must be disabled here before the function ++ * tracer can trace. Break up preempt_disable() into two ++ * calls. One to disable preemption without fear of being ++ * traced. The other to still record the preemption latency, ++ * which can also be traced by the function tracer. ++ */ ++ preempt_disable_notrace(); ++ preempt_latency_start(1); ++ /* ++ * Needs preempt disabled in case user_exit() is traced ++ * and the tracer calls preempt_enable_notrace() causing ++ * an infinite recursion. ++ */ ++ prev_ctx = exception_enter(); ++ __schedule(true); ++ exception_exit(prev_ctx); ++ ++ preempt_latency_stop(1); ++ preempt_enable_no_resched_notrace(); ++ } while (need_resched()); ++} ++EXPORT_SYMBOL_GPL(preempt_schedule_notrace); ++ ++#endif /* CONFIG_PREEMPTION */ ++ ++/* ++ * This is the entry point to schedule() from kernel preemption ++ * off of irq context. ++ * Note, that this is called and return with irqs disabled. This will ++ * protect us against recursive calling from irq. ++ */ ++asmlinkage __visible void __sched preempt_schedule_irq(void) ++{ ++ enum ctx_state prev_state; ++ ++ /* Catch callers which need to be fixed */ ++ BUG_ON(preempt_count() || !irqs_disabled()); ++ ++ prev_state = exception_enter(); ++ ++ do { ++ preempt_disable(); ++ local_irq_enable(); ++ __schedule(true); ++ local_irq_disable(); ++ sched_preempt_enable_no_resched(); ++ } while (need_resched()); ++ ++ exception_exit(prev_state); ++} ++ ++int default_wake_function(wait_queue_entry_t *curr, unsigned mode, int wake_flags, ++ void *key) ++{ ++ return try_to_wake_up(curr->private, mode, wake_flags); ++} ++EXPORT_SYMBOL(default_wake_function); ++ ++static inline void ++check_task_changed(struct rq *rq, struct task_struct *p) ++{ ++ /* ++ * Trigger changes when task priority/deadline modified. ++ */ ++ if (task_on_rq_queued(p)) { ++ struct task_struct *first; ++ ++ requeue_task(p, rq); ++ ++ /* Resched if first queued task not running and not IDLE */ ++ if ((first = rq_first_queued_task(rq)) != rq->curr && ++ !task_running_idle(first)) ++ resched_curr(rq); ++ } ++} ++ ++#ifdef CONFIG_RT_MUTEXES ++ ++static inline int __rt_effective_prio(struct task_struct *pi_task, int prio) ++{ ++ if (pi_task) ++ prio = min(prio, pi_task->prio); ++ ++ return prio; ++} ++ ++static inline int rt_effective_prio(struct task_struct *p, int prio) ++{ ++ struct task_struct *pi_task = rt_mutex_get_top_task(p); ++ ++ return __rt_effective_prio(pi_task, prio); ++} ++ ++/* ++ * rt_mutex_setprio - set the current priority of a task ++ * @p: task to boost ++ * @pi_task: donor task ++ * ++ * This function changes the 'effective' priority of a task. It does ++ * not touch ->normal_prio like __setscheduler(). ++ * ++ * Used by the rt_mutex code to implement priority inheritance ++ * logic. Call site only calls if the priority of the task changed. ++ */ ++void rt_mutex_setprio(struct task_struct *p, struct task_struct *pi_task) ++{ ++ int prio; ++ struct rq *rq; ++ raw_spinlock_t *lock; ++ ++ /* XXX used to be waiter->prio, not waiter->task->prio */ ++ prio = __rt_effective_prio(pi_task, p->normal_prio); ++ ++ /* ++ * If nothing changed; bail early. ++ */ ++ if (p->pi_top_task == pi_task && prio == p->prio) ++ return; ++ ++ rq = __task_access_lock(p, &lock); ++ /* ++ * Set under pi_lock && rq->lock, such that the value can be used under ++ * either lock. ++ * ++ * Note that there is loads of tricky to make this pointer cache work ++ * right. rt_mutex_slowunlock()+rt_mutex_postunlock() work together to ++ * ensure a task is de-boosted (pi_task is set to NULL) before the ++ * task is allowed to run again (and can exit). This ensures the pointer ++ * points to a blocked task -- which guaratees the task is present. ++ */ ++ p->pi_top_task = pi_task; ++ ++ /* ++ * For FIFO/RR we only need to set prio, if that matches we're done. ++ */ ++ if (prio == p->prio) ++ goto out_unlock; ++ ++ /* ++ * Idle task boosting is a nono in general. There is one ++ * exception, when PREEMPT_RT and NOHZ is active: ++ * ++ * The idle task calls get_next_timer_interrupt() and holds ++ * the timer wheel base->lock on the CPU and another CPU wants ++ * to access the timer (probably to cancel it). We can safely ++ * ignore the boosting request, as the idle CPU runs this code ++ * with interrupts disabled and will complete the lock ++ * protected section without being interrupted. So there is no ++ * real need to boost. ++ */ ++ if (unlikely(p == rq->idle)) { ++ WARN_ON(p != rq->curr); ++ WARN_ON(p->pi_blocked_on); ++ goto out_unlock; ++ } ++ ++ trace_sched_pi_setprio(p, pi_task); ++ p->prio = prio; ++ update_task_priodl(p); ++ ++ check_task_changed(rq, p); ++ ++out_unlock: ++ __task_access_unlock(p, lock); ++} ++#else ++static inline int rt_effective_prio(struct task_struct *p, int prio) ++{ ++ return prio; ++} ++#endif ++ ++void set_user_nice(struct task_struct *p, long nice) ++{ ++ int new_static; ++ unsigned long flags; ++ struct rq *rq; ++ raw_spinlock_t *lock; ++ ++ if (task_nice(p) == nice || nice < MIN_NICE || nice > MAX_NICE) ++ return; ++ new_static = NICE_TO_PRIO(nice); ++ /* ++ * We have to be careful, if called from sys_setpriority(), ++ * the task might be in the middle of scheduling on another CPU. ++ */ ++ raw_spin_lock_irqsave(&p->pi_lock, flags); ++ rq = __task_access_lock(p, &lock); ++ ++ /* rq lock may not held!! */ ++ update_rq_clock(rq); ++ ++ p->static_prio = new_static; ++ /* ++ * The RT priorities are set via sched_setscheduler(), but we still ++ * allow the 'normal' nice value to be set - but as expected ++ * it wont have any effect on scheduling until the task is ++ * not SCHED_NORMAL/SCHED_BATCH: ++ */ ++ if (task_has_rt_policy(p)) ++ goto out_unlock; ++ ++ p->deadline -= task_deadline_diff(p); ++ p->deadline += static_deadline_diff(new_static); ++ p->prio = effective_prio(p); ++ update_task_priodl(p); ++ ++ check_task_changed(rq, p); ++out_unlock: ++ __task_access_unlock(p, lock); ++ raw_spin_unlock_irqrestore(&p->pi_lock, flags); ++} ++EXPORT_SYMBOL(set_user_nice); ++ ++/* ++ * can_nice - check if a task can reduce its nice value ++ * @p: task ++ * @nice: nice value ++ */ ++int can_nice(const struct task_struct *p, const int nice) ++{ ++ /* Convert nice value [19,-20] to rlimit style value [1,40] */ ++ int nice_rlim = nice_to_rlimit(nice); ++ ++ return (nice_rlim <= task_rlimit(p, RLIMIT_NICE) || ++ capable(CAP_SYS_NICE)); ++} ++ ++#ifdef __ARCH_WANT_SYS_NICE ++ ++/* ++ * sys_nice - change the priority of the current process. ++ * @increment: priority increment ++ * ++ * sys_setpriority is a more generic, but much slower function that ++ * does similar things. ++ */ ++SYSCALL_DEFINE1(nice, int, increment) ++{ ++ long nice, retval; ++ ++ /* ++ * Setpriority might change our priority at the same moment. ++ * We don't have to worry. Conceptually one call occurs first ++ * and we have a single winner. ++ */ ++ ++ increment = clamp(increment, -NICE_WIDTH, NICE_WIDTH); ++ nice = task_nice(current) + increment; ++ ++ nice = clamp_val(nice, MIN_NICE, MAX_NICE); ++ if (increment < 0 && !can_nice(current, nice)) ++ return -EPERM; ++ ++ retval = security_task_setnice(current, nice); ++ if (retval) ++ return retval; ++ ++ set_user_nice(current, nice); ++ return 0; ++} ++ ++#endif ++ ++/** ++ * task_prio - return the priority value of a given task. ++ * @p: the task in question. ++ * ++ * Return: The priority value as seen by users in /proc. ++ * RT tasks are offset by -100. Normal tasks are centered around 1, value goes ++ * from 0(SCHED_ISO) up to 82 (nice +19 SCHED_IDLE). ++ */ ++int task_prio(const struct task_struct *p) ++{ ++ int level, prio = p->prio - MAX_RT_PRIO; ++ static const int level_to_nice_prio[] = {39, 33, 26, 20, 14, 7, 0, 0}; ++ ++ /* rt tasks */ ++ if (prio <= 0) ++ goto out; ++ ++ preempt_disable(); ++ level = task_deadline_level(p, this_rq()); ++ preempt_enable(); ++ prio += level_to_nice_prio[level]; ++ if (idleprio_task(p)) ++ prio += NICE_WIDTH; ++out: ++ return prio; ++} ++ ++/** ++ * idle_cpu - is a given CPU idle currently? ++ * @cpu: the processor in question. ++ * ++ * Return: 1 if the CPU is currently idle. 0 otherwise. ++ */ ++int idle_cpu(int cpu) ++{ ++ return cpu_curr(cpu) == cpu_rq(cpu)->idle; ++} ++ ++/** ++ * idle_task - return the idle task for a given CPU. ++ * @cpu: the processor in question. ++ * ++ * Return: The idle task for the cpu @cpu. ++ */ ++struct task_struct *idle_task(int cpu) ++{ ++ return cpu_rq(cpu)->idle; ++} ++ ++/** ++ * find_process_by_pid - find a process with a matching PID value. ++ * @pid: the pid in question. ++ * ++ * The task of @pid, if found. %NULL otherwise. ++ */ ++static inline struct task_struct *find_process_by_pid(pid_t pid) ++{ ++ return pid ? find_task_by_vpid(pid) : current; ++} ++ ++#ifdef CONFIG_SMP ++void sched_set_stop_task(int cpu, struct task_struct *stop) ++{ ++ struct sched_param stop_param = { .sched_priority = STOP_PRIO }; ++ struct sched_param start_param = { .sched_priority = 0 }; ++ struct task_struct *old_stop = cpu_rq(cpu)->stop; ++ ++ if (stop) { ++ /* ++ * Make it appear like a SCHED_FIFO task, its something ++ * userspace knows about and won't get confused about. ++ * ++ * Also, it will make PI more or less work without too ++ * much confusion -- but then, stop work should not ++ * rely on PI working anyway. ++ */ ++ sched_setscheduler_nocheck(stop, SCHED_FIFO, &stop_param); ++ } ++ ++ cpu_rq(cpu)->stop = stop; ++ ++ if (old_stop) { ++ /* ++ * Reset it back to a normal scheduling policy so that ++ * it can die in pieces. ++ */ ++ sched_setscheduler_nocheck(old_stop, SCHED_NORMAL, &start_param); ++ } ++} ++ ++/* ++ * Change a given task's CPU affinity. Migrate the thread to a ++ * proper CPU and schedule it away if the CPU it's executing on ++ * is removed from the allowed bitmask. ++ * ++ * NOTE: the caller must have a valid reference to the task, the ++ * task must not exit() & deallocate itself prematurely. The ++ * call is not atomic; no spinlocks may be held. ++ */ ++static int __set_cpus_allowed_ptr(struct task_struct *p, ++ const struct cpumask *new_mask, bool check) ++{ ++ const struct cpumask *cpu_valid_mask = cpu_active_mask; ++ int dest_cpu; ++ unsigned long flags; ++ struct rq *rq; ++ raw_spinlock_t *lock; ++ int ret = 0; ++ ++ raw_spin_lock_irqsave(&p->pi_lock, flags); ++ rq = __task_access_lock(p, &lock); ++ ++ if (p->flags & PF_KTHREAD) { ++ /* ++ * Kernel threads are allowed on online && !active CPUs ++ */ ++ cpu_valid_mask = cpu_online_mask; ++ } ++ ++ /* ++ * Must re-check here, to close a race against __kthread_bind(), ++ * sched_setaffinity() is not guaranteed to observe the flag. ++ */ ++ if (check && (p->flags & PF_NO_SETAFFINITY)) { ++ ret = -EINVAL; ++ goto out; ++ } ++ ++ if (cpumask_equal(&p->cpus_mask, new_mask)) ++ goto out; ++ ++ dest_cpu = cpumask_any_and(cpu_valid_mask, new_mask); ++ if (dest_cpu >= nr_cpu_ids) { ++ ret = -EINVAL; ++ goto out; ++ } ++ ++ do_set_cpus_allowed(p, new_mask); ++ ++ if (p->flags & PF_KTHREAD) { ++ /* ++ * For kernel threads that do indeed end up on online && ++ * !active we want to ensure they are strict per-CPU threads. ++ */ ++ WARN_ON(cpumask_intersects(new_mask, cpu_online_mask) && ++ !cpumask_intersects(new_mask, cpu_active_mask) && ++ p->nr_cpus_allowed != 1); ++ } ++ ++ /* Can the task run on the task's current CPU? If so, we're done */ ++ if (cpumask_test_cpu(task_cpu(p), new_mask)) ++ goto out; ++ ++ if (task_running(p) || p->state == TASK_WAKING) { ++ struct migration_arg arg = { p, dest_cpu }; ++ ++ /* Need help from migration thread: drop lock and wait. */ ++ __task_access_unlock(p, lock); ++ raw_spin_unlock_irqrestore(&p->pi_lock, flags); ++ stop_one_cpu(cpu_of(rq), migration_cpu_stop, &arg); ++ return 0; ++ } ++ if (task_on_rq_queued(p)) { ++ /* ++ * OK, since we're going to drop the lock immediately ++ * afterwards anyway. ++ */ ++ update_rq_clock(rq); ++ rq = move_queued_task(rq, p, dest_cpu); ++ lock = &rq->lock; ++ } ++ ++out: ++ __task_access_unlock(p, lock); ++ raw_spin_unlock_irqrestore(&p->pi_lock, flags); ++ ++ return ret; ++} ++ ++int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask) ++{ ++ return __set_cpus_allowed_ptr(p, new_mask, false); ++} ++EXPORT_SYMBOL_GPL(set_cpus_allowed_ptr); ++ ++#else ++static inline int ++__set_cpus_allowed_ptr(struct task_struct *p, ++ const struct cpumask *new_mask, bool check) ++{ ++ return set_cpus_allowed_ptr(p, new_mask); ++} ++#endif ++ ++static u64 task_init_deadline(const struct task_struct *p) ++{ ++ return task_rq(p)->clock + task_deadline_diff(p); ++} ++ ++u64 (* task_init_deadline_func_tbl[])(const struct task_struct *p) = { ++ task_init_deadline, /* SCHED_NORMAL */ ++ NULL, /* SCHED_FIFO */ ++ NULL, /* SCHED_RR */ ++ task_init_deadline, /* SCHED_BATCH */ ++ NULL, /* SCHED_ISO */ ++ task_init_deadline /* SCHED_IDLE */ ++}; ++ ++/* ++ * sched_setparam() passes in -1 for its policy, to let the functions ++ * it calls know not to change it. ++ */ ++#define SETPARAM_POLICY -1 ++ ++static void __setscheduler_params(struct task_struct *p, ++ const struct sched_attr *attr) ++{ ++ int old_policy = p->policy; ++ int policy = attr->sched_policy; ++ ++ if (policy == SETPARAM_POLICY) ++ policy = p->policy; ++ ++ p->policy = policy; ++ ++ /* ++ * allow normal nice value to be set, but will not have any ++ * effect on scheduling until the task not SCHED_NORMAL/ ++ * SCHED_BATCH ++ */ ++ p->static_prio = NICE_TO_PRIO(attr->sched_nice); ++ ++ /* ++ * __sched_setscheduler() ensures attr->sched_priority == 0 when ++ * !rt_policy. Always setting this ensures that things like ++ * getparam()/getattr() don't report silly values for !rt tasks. ++ */ ++ p->rt_priority = attr->sched_priority; ++ p->normal_prio = normal_prio(p); ++ ++ if (old_policy != policy) ++ p->deadline = (task_init_deadline_func_tbl[p->policy])? ++ task_init_deadline_func_tbl[p->policy](p):0ULL; ++} ++ ++/* Actually do priority change: must hold rq lock. */ ++static void __setscheduler(struct rq *rq, struct task_struct *p, ++ const struct sched_attr *attr, bool keep_boost) ++{ ++ __setscheduler_params(p, attr); ++ ++ /* ++ * Keep a potential priority boosting if called from ++ * sched_setscheduler(). ++ */ ++ p->prio = normal_prio(p); ++ if (keep_boost) ++ p->prio = rt_effective_prio(p, p->prio); ++ update_task_priodl(p); ++} ++ ++/* ++ * check the target process has a UID that matches the current process's ++ */ ++static bool check_same_owner(struct task_struct *p) ++{ ++ const struct cred *cred = current_cred(), *pcred; ++ bool match; ++ ++ rcu_read_lock(); ++ pcred = __task_cred(p); ++ match = (uid_eq(cred->euid, pcred->euid) || ++ uid_eq(cred->euid, pcred->uid)); ++ rcu_read_unlock(); ++ return match; ++} ++ ++static int ++__sched_setscheduler(struct task_struct *p, ++ const struct sched_attr *attr, bool user, bool pi) ++{ ++ const struct sched_attr dl_squash_attr = { ++ .size = sizeof(struct sched_attr), ++ .sched_policy = SCHED_FIFO, ++ .sched_nice = 0, ++ .sched_priority = 99, ++ }; ++ int newprio = MAX_RT_PRIO - 1 - attr->sched_priority; ++ int retval, oldpolicy = -1; ++ int policy = attr->sched_policy; ++ unsigned long flags; ++ struct rq *rq; ++ int reset_on_fork; ++ raw_spinlock_t *lock; ++ ++ /* The pi code expects interrupts enabled */ ++ BUG_ON(pi && in_interrupt()); ++ ++ /* ++ * PDS supports SCHED_DEADLINE by squash it as prio 0 SCHED_FIFO ++ */ ++ if (unlikely(SCHED_DEADLINE == policy)) { ++ attr = &dl_squash_attr; ++ policy = attr->sched_policy; ++ newprio = MAX_RT_PRIO - 1 - attr->sched_priority; ++ } ++recheck: ++ /* Double check policy once rq lock held */ ++ if (policy < 0) { ++ reset_on_fork = p->sched_reset_on_fork; ++ policy = oldpolicy = p->policy; ++ } else { ++ reset_on_fork = !!(attr->sched_flags & SCHED_RESET_ON_FORK); ++ ++ if (policy > SCHED_IDLE) ++ return -EINVAL; ++ } ++ ++ if (attr->sched_flags & ~(SCHED_FLAG_ALL)) ++ return -EINVAL; ++ ++ /* ++ * Valid priorities for SCHED_FIFO and SCHED_RR are ++ * 1..MAX_USER_RT_PRIO-1, valid priority for SCHED_NORMAL and ++ * SCHED_BATCH and SCHED_IDLE is 0. ++ */ ++ if (attr->sched_priority < 0 || ++ (p->mm && attr->sched_priority > MAX_USER_RT_PRIO - 1) || ++ (!p->mm && attr->sched_priority > MAX_RT_PRIO - 1)) ++ return -EINVAL; ++ if ((SCHED_RR == policy || SCHED_FIFO == policy) != ++ (attr->sched_priority != 0)) ++ return -EINVAL; ++ ++ /* ++ * Allow unprivileged RT tasks to decrease priority: ++ */ ++ if (user && !capable(CAP_SYS_NICE)) { ++ if (SCHED_FIFO == policy || SCHED_RR == policy) { ++ unsigned long rlim_rtprio = ++ task_rlimit(p, RLIMIT_RTPRIO); ++ ++ /* Can't set/change the rt policy */ ++ if (policy != p->policy && !rlim_rtprio) ++ return -EPERM; ++ ++ /* Can't increase priority */ ++ if (attr->sched_priority > p->rt_priority && ++ attr->sched_priority > rlim_rtprio) ++ return -EPERM; ++ } ++ ++ /* Can't change other user's priorities */ ++ if (!check_same_owner(p)) ++ return -EPERM; ++ ++ /* Normal users shall not reset the sched_reset_on_fork flag */ ++ if (p->sched_reset_on_fork && !reset_on_fork) ++ return -EPERM; ++ } ++ ++ if (user) { ++ retval = security_task_setscheduler(p); ++ if (retval) ++ return retval; ++ } ++ ++ if (pi) ++ cpuset_read_lock(); ++ ++ /* ++ * Make sure no PI-waiters arrive (or leave) while we are ++ * changing the priority of the task: ++ */ ++ raw_spin_lock_irqsave(&p->pi_lock, flags); ++ ++ /* ++ * To be able to change p->policy safely, task_access_lock() ++ * must be called. ++ * IF use task_access_lock() here: ++ * For the task p which is not running, reading rq->stop is ++ * racy but acceptable as ->stop doesn't change much. ++ * An enhancemnet can be made to read rq->stop saftly. ++ */ ++ rq = __task_access_lock(p, &lock); ++ ++ /* ++ * Changing the policy of the stop threads its a very bad idea ++ */ ++ if (p == rq->stop) { ++ retval = -EINVAL; ++ goto unlock; ++ } ++ ++ /* ++ * If not changing anything there's no need to proceed further: ++ */ ++ if (unlikely(policy == p->policy)) { ++ if (rt_policy(policy) && attr->sched_priority != p->rt_priority) ++ goto change; ++ if (!rt_policy(policy) && ++ NICE_TO_PRIO(attr->sched_nice) != p->static_prio) ++ goto change; ++ ++ p->sched_reset_on_fork = reset_on_fork; ++ retval = 0; ++ goto unlock; ++ } ++change: ++ ++ /* Re-check policy now with rq lock held */ ++ if (unlikely(oldpolicy != -1 && oldpolicy != p->policy)) { ++ policy = oldpolicy = -1; ++ __task_access_unlock(p, lock); ++ raw_spin_unlock_irqrestore(&p->pi_lock, flags); ++ if (pi) ++ cpuset_read_unlock(); ++ goto recheck; ++ } ++ ++ p->sched_reset_on_fork = reset_on_fork; ++ ++ if (pi) { ++ /* ++ * Take priority boosted tasks into account. If the new ++ * effective priority is unchanged, we just store the new ++ * normal parameters and do not touch the scheduler class and ++ * the runqueue. This will be done when the task deboost ++ * itself. ++ */ ++ if (rt_effective_prio(p, newprio) == p->prio) { ++ __setscheduler_params(p, attr); ++ retval = 0; ++ goto unlock; ++ } ++ } ++ ++ __setscheduler(rq, p, attr, pi); ++ ++ check_task_changed(rq, p); ++ ++ /* Avoid rq from going away on us: */ ++ preempt_disable(); ++ __task_access_unlock(p, lock); ++ raw_spin_unlock_irqrestore(&p->pi_lock, flags); ++ ++ if (pi) { ++ cpuset_read_unlock(); ++ rt_mutex_adjust_pi(p); ++ } ++ ++ preempt_enable(); ++ ++ return 0; ++ ++unlock: ++ __task_access_unlock(p, lock); ++ raw_spin_unlock_irqrestore(&p->pi_lock, flags); ++ if (pi) ++ cpuset_read_unlock(); ++ return retval; ++} ++ ++static int _sched_setscheduler(struct task_struct *p, int policy, ++ const struct sched_param *param, bool check) ++{ ++ struct sched_attr attr = { ++ .sched_policy = policy, ++ .sched_priority = param->sched_priority, ++ .sched_nice = PRIO_TO_NICE(p->static_prio), ++ }; ++ ++ /* Fixup the legacy SCHED_RESET_ON_FORK hack. */ ++ if ((policy != SETPARAM_POLICY) && (policy & SCHED_RESET_ON_FORK)) { ++ attr.sched_flags |= SCHED_FLAG_RESET_ON_FORK; ++ policy &= ~SCHED_RESET_ON_FORK; ++ attr.sched_policy = policy; ++ } ++ ++ return __sched_setscheduler(p, &attr, check, true); ++} ++ ++/** ++ * sched_setscheduler - change the scheduling policy and/or RT priority of a thread. ++ * @p: the task in question. ++ * @policy: new policy. ++ * @param: structure containing the new RT priority. ++ * ++ * Use sched_set_fifo(), read its comment. ++ * ++ * Return: 0 on success. An error code otherwise. ++ * ++ * NOTE that the task may be already dead. ++ */ ++int sched_setscheduler(struct task_struct *p, int policy, ++ const struct sched_param *param) ++{ ++ return _sched_setscheduler(p, policy, param, true); ++} ++ ++int sched_setattr(struct task_struct *p, const struct sched_attr *attr) ++{ ++ return __sched_setscheduler(p, attr, true, true); ++} ++ ++int sched_setattr_nocheck(struct task_struct *p, const struct sched_attr *attr) ++{ ++ return __sched_setscheduler(p, attr, false, true); ++} ++ ++/** ++ * sched_setscheduler_nocheck - change the scheduling policy and/or RT priority of a thread from kernelspace. ++ * @p: the task in question. ++ * @policy: new policy. ++ * @param: structure containing the new RT priority. ++ * ++ * Just like sched_setscheduler, only don't bother checking if the ++ * current context has permission. For example, this is needed in ++ * stop_machine(): we create temporary high priority worker threads, ++ * but our caller might not have that capability. ++ * ++ * Return: 0 on success. An error code otherwise. ++ */ ++int sched_setscheduler_nocheck(struct task_struct *p, int policy, ++ const struct sched_param *param) ++{ ++ return _sched_setscheduler(p, policy, param, false); ++} ++ ++/* ++ * SCHED_FIFO is a broken scheduler model; that is, it is fundamentally ++ * incapable of resource management, which is the one thing an OS really should ++ * be doing. ++ * ++ * This is of course the reason it is limited to privileged users only. ++ * ++ * Worse still; it is fundamentally impossible to compose static priority ++ * workloads. You cannot take two correctly working static prio workloads ++ * and smash them together and still expect them to work. ++ * ++ * For this reason 'all' FIFO tasks the kernel creates are basically at: ++ * ++ * MAX_RT_PRIO / 2 ++ * ++ * The administrator _MUST_ configure the system, the kernel simply doesn't ++ * know enough information to make a sensible choice. ++ */ ++void sched_set_fifo(struct task_struct *p) ++{ ++ struct sched_param sp = { .sched_priority = MAX_RT_PRIO / 2 }; ++ WARN_ON_ONCE(sched_setscheduler_nocheck(p, SCHED_FIFO, &sp) != 0); ++} ++EXPORT_SYMBOL_GPL(sched_set_fifo); ++ ++/* ++ * For when you don't much care about FIFO, but want to be above SCHED_NORMAL. ++ */ ++void sched_set_fifo_low(struct task_struct *p) ++{ ++ struct sched_param sp = { .sched_priority = 1 }; ++ WARN_ON_ONCE(sched_setscheduler_nocheck(p, SCHED_FIFO, &sp) != 0); ++} ++EXPORT_SYMBOL_GPL(sched_set_fifo_low); ++ ++void sched_set_normal(struct task_struct *p, int nice) ++{ ++ struct sched_attr attr = { ++ .sched_policy = SCHED_NORMAL, ++ .sched_nice = nice, ++ }; ++ WARN_ON_ONCE(sched_setattr_nocheck(p, &attr) != 0); ++} ++EXPORT_SYMBOL_GPL(sched_set_normal); ++ ++static int ++do_sched_setscheduler(pid_t pid, int policy, struct sched_param __user *param) ++{ ++ struct sched_param lparam; ++ struct task_struct *p; ++ int retval; ++ ++ if (!param || pid < 0) ++ return -EINVAL; ++ if (copy_from_user(&lparam, param, sizeof(struct sched_param))) ++ return -EFAULT; ++ ++ rcu_read_lock(); ++ retval = -ESRCH; ++ p = find_process_by_pid(pid); ++ if (likely(p)) ++ get_task_struct(p); ++ rcu_read_unlock(); ++ ++ if (likely(p)) { ++ retval = sched_setscheduler(p, policy, &lparam); ++ put_task_struct(p); ++ } ++ ++ return retval; ++} ++ ++/* ++ * Mimics kernel/events/core.c perf_copy_attr(). ++ */ ++static int sched_copy_attr(struct sched_attr __user *uattr, struct sched_attr *attr) ++{ ++ u32 size; ++ int ret; ++ ++ /* Zero the full structure, so that a short copy will be nice: */ ++ memset(attr, 0, sizeof(*attr)); ++ ++ ret = get_user(size, &uattr->size); ++ if (ret) ++ return ret; ++ ++ /* ABI compatibility quirk: */ ++ if (!size) ++ size = SCHED_ATTR_SIZE_VER0; ++ ++ if (size < SCHED_ATTR_SIZE_VER0 || size > PAGE_SIZE) ++ goto err_size; ++ ++ ret = copy_struct_from_user(attr, sizeof(*attr), uattr, size); ++ if (ret) { ++ if (ret == -E2BIG) ++ goto err_size; ++ return ret; ++ } ++ ++ /* ++ * XXX: Do we want to be lenient like existing syscalls; or do we want ++ * to be strict and return an error on out-of-bounds values? ++ */ ++ attr->sched_nice = clamp(attr->sched_nice, -20, 19); ++ ++ /* sched/core.c uses zero here but we already know ret is zero */ ++ return 0; ++ ++err_size: ++ put_user(sizeof(*attr), &uattr->size); ++ return -E2BIG; ++} ++ ++/** ++ * sys_sched_setscheduler - set/change the scheduler policy and RT priority ++ * @pid: the pid in question. ++ * @policy: new policy. ++ * ++ * Return: 0 on success. An error code otherwise. ++ * @param: structure containing the new RT priority. ++ */ ++SYSCALL_DEFINE3(sched_setscheduler, pid_t, pid, int, policy, struct sched_param __user *, param) ++{ ++ if (policy < 0) ++ return -EINVAL; ++ ++ return do_sched_setscheduler(pid, policy, param); ++} ++ ++/** ++ * sys_sched_setparam - set/change the RT priority of a thread ++ * @pid: the pid in question. ++ * @param: structure containing the new RT priority. ++ * ++ * Return: 0 on success. An error code otherwise. ++ */ ++SYSCALL_DEFINE2(sched_setparam, pid_t, pid, struct sched_param __user *, param) ++{ ++ return do_sched_setscheduler(pid, SETPARAM_POLICY, param); ++} ++ ++/** ++ * sys_sched_setattr - same as above, but with extended sched_attr ++ * @pid: the pid in question. ++ * @uattr: structure containing the extended parameters. ++ */ ++SYSCALL_DEFINE3(sched_setattr, pid_t, pid, struct sched_attr __user *, uattr, ++ unsigned int, flags) ++{ ++ struct sched_attr attr; ++ struct task_struct *p; ++ int retval; ++ ++ if (!uattr || pid < 0 || flags) ++ return -EINVAL; ++ ++ retval = sched_copy_attr(uattr, &attr); ++ if (retval) ++ return retval; ++ ++ if ((int)attr.sched_policy < 0) ++ return -EINVAL; ++ ++ rcu_read_lock(); ++ retval = -ESRCH; ++ p = find_process_by_pid(pid); ++ if (p != NULL) ++ retval = sched_setattr(p, &attr); ++ rcu_read_unlock(); ++ ++ return retval; ++} ++ ++/** ++ * sys_sched_getscheduler - get the policy (scheduling class) of a thread ++ * @pid: the pid in question. ++ * ++ * Return: On success, the policy of the thread. Otherwise, a negative error ++ * code. ++ */ ++SYSCALL_DEFINE1(sched_getscheduler, pid_t, pid) ++{ ++ struct task_struct *p; ++ int retval = -EINVAL; ++ ++ if (pid < 0) ++ goto out_nounlock; ++ ++ retval = -ESRCH; ++ rcu_read_lock(); ++ p = find_process_by_pid(pid); ++ if (p) { ++ retval = security_task_getscheduler(p); ++ if (!retval) ++ retval = p->policy; ++ } ++ rcu_read_unlock(); ++ ++out_nounlock: ++ return retval; ++} ++ ++/** ++ * sys_sched_getscheduler - get the RT priority of a thread ++ * @pid: the pid in question. ++ * @param: structure containing the RT priority. ++ * ++ * Return: On success, 0 and the RT priority is in @param. Otherwise, an error ++ * code. ++ */ ++SYSCALL_DEFINE2(sched_getparam, pid_t, pid, struct sched_param __user *, param) ++{ ++ struct sched_param lp = { .sched_priority = 0 }; ++ struct task_struct *p; ++ int retval = -EINVAL; ++ ++ if (!param || pid < 0) ++ goto out_nounlock; ++ ++ rcu_read_lock(); ++ p = find_process_by_pid(pid); ++ retval = -ESRCH; ++ if (!p) ++ goto out_unlock; ++ ++ retval = security_task_getscheduler(p); ++ if (retval) ++ goto out_unlock; ++ ++ if (task_has_rt_policy(p)) ++ lp.sched_priority = p->rt_priority; ++ rcu_read_unlock(); ++ ++ /* ++ * This one might sleep, we cannot do it with a spinlock held ... ++ */ ++ retval = copy_to_user(param, &lp, sizeof(*param)) ? -EFAULT : 0; ++ ++out_nounlock: ++ return retval; ++ ++out_unlock: ++ rcu_read_unlock(); ++ return retval; ++} ++ ++/* ++ * Copy the kernel size attribute structure (which might be larger ++ * than what user-space knows about) to user-space. ++ * ++ * Note that all cases are valid: user-space buffer can be larger or ++ * smaller than the kernel-space buffer. The usual case is that both ++ * have the same size. ++ */ ++static int ++sched_attr_copy_to_user(struct sched_attr __user *uattr, ++ struct sched_attr *kattr, ++ unsigned int usize) ++{ ++ unsigned int ksize = sizeof(*kattr); ++ ++ if (!access_ok(uattr, usize)) ++ return -EFAULT; ++ ++ /* ++ * sched_getattr() ABI forwards and backwards compatibility: ++ * ++ * If usize == ksize then we just copy everything to user-space and all is good. ++ * ++ * If usize < ksize then we only copy as much as user-space has space for, ++ * this keeps ABI compatibility as well. We skip the rest. ++ * ++ * If usize > ksize then user-space is using a newer version of the ABI, ++ * which part the kernel doesn't know about. Just ignore it - tooling can ++ * detect the kernel's knowledge of attributes from the attr->size value ++ * which is set to ksize in this case. ++ */ ++ kattr->size = min(usize, ksize); ++ ++ if (copy_to_user(uattr, kattr, kattr->size)) ++ return -EFAULT; ++ ++ return 0; ++} ++ ++/** ++ * sys_sched_getattr - similar to sched_getparam, but with sched_attr ++ * @pid: the pid in question. ++ * @uattr: structure containing the extended parameters. ++ * @usize: sizeof(attr) for fwd/bwd comp. ++ * @flags: for future extension. ++ */ ++SYSCALL_DEFINE4(sched_getattr, pid_t, pid, struct sched_attr __user *, uattr, ++ unsigned int, usize, unsigned int, flags) ++{ ++ struct sched_attr kattr = { }; ++ struct task_struct *p; ++ int retval; ++ ++ if (!uattr || pid < 0 || usize > PAGE_SIZE || ++ usize < SCHED_ATTR_SIZE_VER0 || flags) ++ return -EINVAL; ++ ++ rcu_read_lock(); ++ p = find_process_by_pid(pid); ++ retval = -ESRCH; ++ if (!p) ++ goto out_unlock; ++ ++ retval = security_task_getscheduler(p); ++ if (retval) ++ goto out_unlock; ++ ++ kattr.sched_policy = p->policy; ++ if (rt_task(p)) ++ kattr.sched_priority = p->rt_priority; ++ else ++ kattr.sched_nice = task_nice(p); ++ ++#ifdef CONFIG_UCLAMP_TASK ++ kattr.sched_util_min = p->uclamp_req[UCLAMP_MIN].value; ++ kattr.sched_util_max = p->uclamp_req[UCLAMP_MAX].value; ++#endif ++ ++ rcu_read_unlock(); ++ ++ return sched_attr_copy_to_user(uattr, &kattr, usize); ++ ++out_unlock: ++ rcu_read_unlock(); ++ return retval; ++} ++ ++long sched_setaffinity(pid_t pid, const struct cpumask *in_mask) ++{ ++ cpumask_var_t cpus_mask, new_mask; ++ struct task_struct *p; ++ int retval; ++ ++ get_online_cpus(); ++ rcu_read_lock(); ++ ++ p = find_process_by_pid(pid); ++ if (!p) { ++ rcu_read_unlock(); ++ put_online_cpus(); ++ return -ESRCH; ++ } ++ ++ /* Prevent p going away */ ++ get_task_struct(p); ++ rcu_read_unlock(); ++ ++ if (p->flags & PF_NO_SETAFFINITY) { ++ retval = -EINVAL; ++ goto out_put_task; ++ } ++ if (!alloc_cpumask_var(&cpus_mask, GFP_KERNEL)) { ++ retval = -ENOMEM; ++ goto out_put_task; ++ } ++ if (!alloc_cpumask_var(&new_mask, GFP_KERNEL)) { ++ retval = -ENOMEM; ++ goto out_free_cpus_allowed; ++ } ++ retval = -EPERM; ++ if (!check_same_owner(p)) { ++ rcu_read_lock(); ++ if (!ns_capable(__task_cred(p)->user_ns, CAP_SYS_NICE)) { ++ rcu_read_unlock(); ++ goto out_unlock; ++ } ++ rcu_read_unlock(); ++ } ++ ++ retval = security_task_setscheduler(p); ++ if (retval) ++ goto out_unlock; ++ ++ cpuset_cpus_allowed(p, cpus_mask); ++ cpumask_and(new_mask, in_mask, cpus_mask); ++again: ++ retval = __set_cpus_allowed_ptr(p, new_mask, true); ++ ++ if (!retval) { ++ cpuset_cpus_allowed(p, cpus_mask); ++ if (!cpumask_subset(new_mask, cpus_mask)) { ++ /* ++ * We must have raced with a concurrent cpuset ++ * update. Just reset the cpus_mask to the ++ * cpuset's cpus_mask ++ */ ++ cpumask_copy(new_mask, cpus_mask); ++ goto again; ++ } ++ } ++out_unlock: ++ free_cpumask_var(new_mask); ++out_free_cpus_allowed: ++ free_cpumask_var(cpus_mask); ++out_put_task: ++ put_task_struct(p); ++ put_online_cpus(); ++ return retval; ++} ++ ++static int get_user_cpu_mask(unsigned long __user *user_mask_ptr, unsigned len, ++ struct cpumask *new_mask) ++{ ++ if (len < cpumask_size()) ++ cpumask_clear(new_mask); ++ else if (len > cpumask_size()) ++ len = cpumask_size(); ++ ++ return copy_from_user(new_mask, user_mask_ptr, len) ? -EFAULT : 0; ++} ++ ++/** ++ * sys_sched_setaffinity - set the CPU affinity of a process ++ * @pid: pid of the process ++ * @len: length in bytes of the bitmask pointed to by user_mask_ptr ++ * @user_mask_ptr: user-space pointer to the new CPU mask ++ * ++ * Return: 0 on success. An error code otherwise. ++ */ ++SYSCALL_DEFINE3(sched_setaffinity, pid_t, pid, unsigned int, len, ++ unsigned long __user *, user_mask_ptr) ++{ ++ cpumask_var_t new_mask; ++ int retval; ++ ++ if (!alloc_cpumask_var(&new_mask, GFP_KERNEL)) ++ return -ENOMEM; ++ ++ retval = get_user_cpu_mask(user_mask_ptr, len, new_mask); ++ if (retval == 0) ++ retval = sched_setaffinity(pid, new_mask); ++ free_cpumask_var(new_mask); ++ return retval; ++} ++ ++long sched_getaffinity(pid_t pid, cpumask_t *mask) ++{ ++ struct task_struct *p; ++ raw_spinlock_t *lock; ++ unsigned long flags; ++ int retval; ++ ++ rcu_read_lock(); ++ ++ retval = -ESRCH; ++ p = find_process_by_pid(pid); ++ if (!p) ++ goto out_unlock; ++ ++ retval = security_task_getscheduler(p); ++ if (retval) ++ goto out_unlock; ++ ++ task_access_lock_irqsave(p, &lock, &flags); ++ cpumask_and(mask, &p->cpus_mask, cpu_active_mask); ++ task_access_unlock_irqrestore(p, lock, &flags); ++ ++out_unlock: ++ rcu_read_unlock(); ++ ++ return retval; ++} ++ ++/** ++ * sys_sched_getaffinity - get the CPU affinity of a process ++ * @pid: pid of the process ++ * @len: length in bytes of the bitmask pointed to by user_mask_ptr ++ * @user_mask_ptr: user-space pointer to hold the current CPU mask ++ * ++ * Return: size of CPU mask copied to user_mask_ptr on success. An ++ * error code otherwise. ++ */ ++SYSCALL_DEFINE3(sched_getaffinity, pid_t, pid, unsigned int, len, ++ unsigned long __user *, user_mask_ptr) ++{ ++ int ret; ++ cpumask_var_t mask; ++ ++ if ((len * BITS_PER_BYTE) < nr_cpu_ids) ++ return -EINVAL; ++ if (len & (sizeof(unsigned long)-1)) ++ return -EINVAL; ++ ++ if (!alloc_cpumask_var(&mask, GFP_KERNEL)) ++ return -ENOMEM; ++ ++ ret = sched_getaffinity(pid, mask); ++ if (ret == 0) { ++ unsigned int retlen = min_t(size_t, len, cpumask_size()); ++ ++ if (copy_to_user(user_mask_ptr, mask, retlen)) ++ ret = -EFAULT; ++ else ++ ret = retlen; ++ } ++ free_cpumask_var(mask); ++ ++ return ret; ++} ++ ++/** ++ * sys_sched_yield - yield the current processor to other threads. ++ * ++ * This function yields the current CPU to other tasks. It does this by ++ * scheduling away the current task. If it still has the earliest deadline ++ * it will be scheduled again as the next task. ++ * ++ * Return: 0. ++ */ ++static void do_sched_yield(void) ++{ ++ struct rq *rq; ++ struct rq_flags rf; ++ ++ if (!sched_yield_type) ++ return; ++ ++ rq = this_rq_lock_irq(&rf); ++ ++ if (sched_yield_type > 1) { ++ time_slice_expired(current, rq); ++ requeue_task(current, rq); ++ } ++ schedstat_inc(rq->yld_count); ++ ++ /* ++ * Since we are going to call schedule() anyway, there's ++ * no need to preempt or enable interrupts: ++ */ ++ preempt_disable(); ++ raw_spin_unlock(&rq->lock); ++ sched_preempt_enable_no_resched(); ++ ++ schedule(); ++} ++ ++SYSCALL_DEFINE0(sched_yield) ++{ ++ do_sched_yield(); ++ return 0; ++} ++ ++#ifndef CONFIG_PREEMPTION ++int __sched _cond_resched(void) ++{ ++ if (should_resched(0)) { ++ preempt_schedule_common(); ++ return 1; ++ } ++ rcu_all_qs(); ++ return 0; ++} ++EXPORT_SYMBOL(_cond_resched); ++#endif ++ ++/* ++ * __cond_resched_lock() - if a reschedule is pending, drop the given lock, ++ * call schedule, and on return reacquire the lock. ++ * ++ * This works OK both with and without CONFIG_PREEMPTION. We do strange low-level ++ * operations here to prevent schedule() from being called twice (once via ++ * spin_unlock(), once by hand). ++ */ ++int __cond_resched_lock(spinlock_t *lock) ++{ ++ int resched = should_resched(PREEMPT_LOCK_OFFSET); ++ int ret = 0; ++ ++ lockdep_assert_held(lock); ++ ++ if (spin_needbreak(lock) || resched) { ++ spin_unlock(lock); ++ if (resched) ++ preempt_schedule_common(); ++ else ++ cpu_relax(); ++ ret = 1; ++ spin_lock(lock); ++ } ++ return ret; ++} ++EXPORT_SYMBOL(__cond_resched_lock); ++ ++/** ++ * yield - yield the current processor to other threads. ++ * ++ * Do not ever use this function, there's a 99% chance you're doing it wrong. ++ * ++ * The scheduler is at all times free to pick the calling task as the most ++ * eligible task to run, if removing the yield() call from your code breaks ++ * it, its already broken. ++ * ++ * Typical broken usage is: ++ * ++ * while (!event) ++ * yield(); ++ * ++ * where one assumes that yield() will let 'the other' process run that will ++ * make event true. If the current task is a SCHED_FIFO task that will never ++ * happen. Never use yield() as a progress guarantee!! ++ * ++ * If you want to use yield() to wait for something, use wait_event(). ++ * If you want to use yield() to be 'nice' for others, use cond_resched(). ++ * If you still want to use yield(), do not! ++ */ ++void __sched yield(void) ++{ ++ set_current_state(TASK_RUNNING); ++ do_sched_yield(); ++} ++EXPORT_SYMBOL(yield); ++ ++/** ++ * yield_to - yield the current processor to another thread in ++ * your thread group, or accelerate that thread toward the ++ * processor it's on. ++ * @p: target task ++ * @preempt: whether task preemption is allowed or not ++ * ++ * It's the caller's job to ensure that the target task struct ++ * can't go away on us before we can do any checks. ++ * ++ * In PDS, yield_to is not supported. ++ * ++ * Return: ++ * true (>0) if we indeed boosted the target task. ++ * false (0) if we failed to boost the target. ++ * -ESRCH if there's no task to yield to. ++ */ ++int __sched yield_to(struct task_struct *p, bool preempt) ++{ ++ return 0; ++} ++EXPORT_SYMBOL_GPL(yield_to); ++ ++int io_schedule_prepare(void) ++{ ++ int old_iowait = current->in_iowait; ++ ++ current->in_iowait = 1; ++ blk_schedule_flush_plug(current); ++ ++ return old_iowait; ++} ++ ++void io_schedule_finish(int token) ++{ ++ current->in_iowait = token; ++} ++ ++/* ++ * This task is about to go to sleep on IO. Increment rq->nr_iowait so ++ * that process accounting knows that this is a task in IO wait state. ++ * ++ * But don't do that if it is a deliberate, throttling IO wait (this task ++ * has set its backing_dev_info: the queue against which it should throttle) ++ */ ++ ++long __sched io_schedule_timeout(long timeout) ++{ ++ int token; ++ long ret; ++ ++ token = io_schedule_prepare(); ++ ret = schedule_timeout(timeout); ++ io_schedule_finish(token); ++ ++ return ret; ++} ++EXPORT_SYMBOL(io_schedule_timeout); ++ ++void io_schedule(void) ++{ ++ int token; ++ ++ token = io_schedule_prepare(); ++ schedule(); ++ io_schedule_finish(token); ++} ++EXPORT_SYMBOL(io_schedule); ++ ++/** ++ * sys_sched_get_priority_max - return maximum RT priority. ++ * @policy: scheduling class. ++ * ++ * Return: On success, this syscall returns the maximum ++ * rt_priority that can be used by a given scheduling class. ++ * On failure, a negative error code is returned. ++ */ ++SYSCALL_DEFINE1(sched_get_priority_max, int, policy) ++{ ++ int ret = -EINVAL; ++ ++ switch (policy) { ++ case SCHED_FIFO: ++ case SCHED_RR: ++ ret = MAX_USER_RT_PRIO-1; ++ break; ++ case SCHED_NORMAL: ++ case SCHED_BATCH: ++ case SCHED_ISO: ++ case SCHED_IDLE: ++ ret = 0; ++ break; ++ } ++ return ret; ++} ++ ++/** ++ * sys_sched_get_priority_min - return minimum RT priority. ++ * @policy: scheduling class. ++ * ++ * Return: On success, this syscall returns the minimum ++ * rt_priority that can be used by a given scheduling class. ++ * On failure, a negative error code is returned. ++ */ ++SYSCALL_DEFINE1(sched_get_priority_min, int, policy) ++{ ++ int ret = -EINVAL; ++ ++ switch (policy) { ++ case SCHED_FIFO: ++ case SCHED_RR: ++ ret = 1; ++ break; ++ case SCHED_NORMAL: ++ case SCHED_BATCH: ++ case SCHED_ISO: ++ case SCHED_IDLE: ++ ret = 0; ++ break; ++ } ++ return ret; ++} ++ ++static int sched_rr_get_interval(pid_t pid, struct timespec64 *t) ++{ ++ struct task_struct *p; ++ int retval; ++ ++ if (pid < 0) ++ return -EINVAL; ++ ++ retval = -ESRCH; ++ rcu_read_lock(); ++ p = find_process_by_pid(pid); ++ if (!p) ++ goto out_unlock; ++ ++ retval = security_task_getscheduler(p); ++ if (retval) ++ goto out_unlock; ++ rcu_read_unlock(); ++ ++ *t = ns_to_timespec64(MS_TO_NS(rr_interval)); ++ return 0; ++ ++out_unlock: ++ rcu_read_unlock(); ++ return retval; ++} ++ ++/** ++ * sys_sched_rr_get_interval - return the default timeslice of a process. ++ * @pid: pid of the process. ++ * @interval: userspace pointer to the timeslice value. ++ * ++ * ++ * Return: On success, 0 and the timeslice is in @interval. Otherwise, ++ * an error code. ++ */ ++SYSCALL_DEFINE2(sched_rr_get_interval, pid_t, pid, ++ struct __kernel_timespec __user *, interval) ++{ ++ struct timespec64 t; ++ int retval = sched_rr_get_interval(pid, &t); ++ ++ if (retval == 0) ++ retval = put_timespec64(&t, interval); ++ ++ return retval; ++} ++ ++#ifdef CONFIG_COMPAT_32BIT_TIME ++SYSCALL_DEFINE2(sched_rr_get_interval_time32, pid_t, pid, ++ struct old_timespec32 __user *, interval) ++{ ++ struct timespec64 t; ++ int retval = sched_rr_get_interval(pid, &t); ++ ++ if (retval == 0) ++ retval = put_old_timespec32(&t, interval); ++ return retval; ++} ++#endif ++ ++void sched_show_task(struct task_struct *p) ++{ ++ unsigned long free = 0; ++ int ppid; ++ ++ if (!try_get_task_stack(p)) ++ return; ++ ++ pr_info("task:%-15.15s state:%c", p->comm, task_state_to_char(p)); ++ ++ if (p->state == TASK_RUNNING) ++ pr_cont(" running task "); ++#ifdef CONFIG_DEBUG_STACK_USAGE ++ free = stack_not_used(p); ++#endif ++ ppid = 0; ++ rcu_read_lock(); ++ if (pid_alive(p)) ++ ppid = task_pid_nr(rcu_dereference(p->real_parent)); ++ rcu_read_unlock(); ++ pr_cont(" stack:%5lu pid:%5d ppid:%6d flags:0x%08lx\n", ++ free, task_pid_nr(p), ppid, ++ (unsigned long)task_thread_info(p)->flags); ++ ++ print_worker_info(KERN_INFO, p); ++ show_stack(p, NULL, KERN_INFO); ++ put_task_stack(p); ++} ++EXPORT_SYMBOL_GPL(sched_show_task); ++ ++static inline bool ++state_filter_match(unsigned long state_filter, struct task_struct *p) ++{ ++ /* no filter, everything matches */ ++ if (!state_filter) ++ return true; ++ ++ /* filter, but doesn't match */ ++ if (!(p->state & state_filter)) ++ return false; ++ ++ /* ++ * When looking for TASK_UNINTERRUPTIBLE skip TASK_IDLE (allows ++ * TASK_KILLABLE). ++ */ ++ if (state_filter == TASK_UNINTERRUPTIBLE && p->state == TASK_IDLE) ++ return false; ++ ++ return true; ++} ++ ++ ++void show_state_filter(unsigned long state_filter) ++{ ++ struct task_struct *g, *p; ++ ++ rcu_read_lock(); ++ for_each_process_thread(g, p) { ++ /* ++ * reset the NMI-timeout, listing all files on a slow ++ * console might take a lot of time: ++ * Also, reset softlockup watchdogs on all CPUs, because ++ * another CPU might be blocked waiting for us to process ++ * an IPI. ++ */ ++ touch_nmi_watchdog(); ++ touch_all_softlockup_watchdogs(); ++ if (state_filter_match(state_filter, p)) ++ sched_show_task(p); ++ } ++ ++#ifdef CONFIG_SCHED_DEBUG ++ /* PDS TODO: should support this ++ if (!state_filter) ++ sysrq_sched_debug_show(); ++ */ ++#endif ++ rcu_read_unlock(); ++ /* ++ * Only show locks if all tasks are dumped: ++ */ ++ if (!state_filter) ++ debug_show_all_locks(); ++} ++ ++void dump_cpu_task(int cpu) ++{ ++ pr_info("Task dump for CPU %d:\n", cpu); ++ sched_show_task(cpu_curr(cpu)); ++} ++ ++/** ++ * init_idle - set up an idle thread for a given CPU ++ * @idle: task in question ++ * @cpu: cpu the idle task belongs to ++ * ++ * NOTE: this function does not set the idle thread's NEED_RESCHED ++ * flag, to make booting more robust. ++ */ ++void init_idle(struct task_struct *idle, int cpu) ++{ ++ struct rq *rq = cpu_rq(cpu); ++ unsigned long flags; ++ ++ raw_spin_lock_irqsave(&idle->pi_lock, flags); ++ raw_spin_lock(&rq->lock); ++ update_rq_clock(rq); ++ ++ idle->last_ran = rq->clock_task; ++ idle->state = TASK_RUNNING; ++ idle->flags |= PF_IDLE; ++ /* Setting prio to illegal value shouldn't matter when never queued */ ++ idle->prio = PRIO_LIMIT; ++ idle->deadline = rq_clock(rq) + task_deadline_diff(idle); ++ update_task_priodl(idle); ++ ++ kasan_unpoison_task_stack(idle); ++ ++#ifdef CONFIG_SMP ++ /* ++ * It's possible that init_idle() gets called multiple times on a task, ++ * in that case do_set_cpus_allowed() will not do the right thing. ++ * ++ * And since this is boot we can forgo the serialisation. ++ */ ++ set_cpus_allowed_common(idle, cpumask_of(cpu)); ++#endif ++ ++ /* Silence PROVE_RCU */ ++ rcu_read_lock(); ++ __set_task_cpu(idle, cpu); ++ rcu_read_unlock(); ++ ++ rq->idle = idle; ++ rcu_assign_pointer(rq->curr, idle); ++ idle->on_cpu = 1; ++ ++ raw_spin_unlock(&rq->lock); ++ raw_spin_unlock_irqrestore(&idle->pi_lock, flags); ++ ++ /* Set the preempt count _outside_ the spinlocks! */ ++ init_idle_preempt_count(idle, cpu); ++ ++ ftrace_graph_init_idle_task(idle, cpu); ++ vtime_init_idle(idle, cpu); ++#ifdef CONFIG_SMP ++ sprintf(idle->comm, "%s/%d", INIT_TASK_COMM, cpu); ++#endif ++} ++ ++void resched_cpu(int cpu) ++{ ++ struct rq *rq = cpu_rq(cpu); ++ unsigned long flags; ++ ++ raw_spin_lock_irqsave(&rq->lock, flags); ++ if (cpu_online(cpu) || cpu == smp_processor_id()) ++ resched_curr(cpu_rq(cpu)); ++ raw_spin_unlock_irqrestore(&rq->lock, flags); ++} ++ ++static bool __wake_q_add(struct wake_q_head *head, struct task_struct *task) ++{ ++ struct wake_q_node *node = &task->wake_q; ++ ++ /* ++ * Atomically grab the task, if ->wake_q is !nil already it means ++ * its already queued (either by us or someone else) and will get the ++ * wakeup due to that. ++ * ++ * In order to ensure that a pending wakeup will observe our pending ++ * state, even in the failed case, an explicit smp_mb() must be used. ++ */ ++ smp_mb__before_atomic(); ++ if (unlikely(cmpxchg_relaxed(&node->next, NULL, WAKE_Q_TAIL))) ++ return false; ++ ++ /* ++ * The head is context local, there can be no concurrency. ++ */ ++ *head->lastp = node; ++ head->lastp = &node->next; ++ return true; ++} ++ ++/** ++ * wake_q_add() - queue a wakeup for 'later' waking. ++ * @head: the wake_q_head to add @task to ++ * @task: the task to queue for 'later' wakeup ++ * ++ * Queue a task for later wakeup, most likely by the wake_up_q() call in the ++ * same context, _HOWEVER_ this is not guaranteed, the wakeup can come ++ * instantly. ++ * ++ * This function must be used as-if it were wake_up_process(); IOW the task ++ * must be ready to be woken at this location. ++ */ ++void wake_q_add(struct wake_q_head *head, struct task_struct *task) ++{ ++ if (__wake_q_add(head, task)) ++ get_task_struct(task); ++} ++ ++/** ++ * wake_q_add_safe() - safely queue a wakeup for 'later' waking. ++ * @head: the wake_q_head to add @task to ++ * @task: the task to queue for 'later' wakeup ++ * ++ * Queue a task for later wakeup, most likely by the wake_up_q() call in the ++ * same context, _HOWEVER_ this is not guaranteed, the wakeup can come ++ * instantly. ++ * ++ * This function must be used as-if it were wake_up_process(); IOW the task ++ * must be ready to be woken at this location. ++ * ++ * This function is essentially a task-safe equivalent to wake_q_add(). Callers ++ * that already hold reference to @task can call the 'safe' version and trust ++ * wake_q to do the right thing depending whether or not the @task is already ++ * queued for wakeup. ++ */ ++void wake_q_add_safe(struct wake_q_head *head, struct task_struct *task) ++{ ++ if (!__wake_q_add(head, task)) ++ put_task_struct(task); ++} ++ ++void wake_up_q(struct wake_q_head *head) ++{ ++ struct wake_q_node *node = head->first; ++ ++ while (node != WAKE_Q_TAIL) { ++ struct task_struct *task; ++ ++ task = container_of(node, struct task_struct, wake_q); ++ BUG_ON(!task); ++ /* task can safely be re-inserted now: */ ++ node = node->next; ++ task->wake_q.next = NULL; ++ ++ /* ++ * wake_up_process() executes a full barrier, which pairs with ++ * the queueing in wake_q_add() so as not to miss wakeups. ++ */ ++ wake_up_process(task); ++ put_task_struct(task); ++ } ++} ++ ++#ifdef CONFIG_SMP ++ ++int cpuset_cpumask_can_shrink(const struct cpumask __maybe_unused *cur, ++ const struct cpumask __maybe_unused *trial) ++{ ++ return 1; ++} ++ ++int task_can_attach(struct task_struct *p, ++ const struct cpumask *cs_cpus_allowed) ++{ ++ int ret = 0; ++ ++ /* ++ * Kthreads which disallow setaffinity shouldn't be moved ++ * to a new cpuset; we don't want to change their CPU ++ * affinity and isolating such threads by their set of ++ * allowed nodes is unnecessary. Thus, cpusets are not ++ * applicable for such threads. This prevents checking for ++ * success of set_cpus_allowed_ptr() on all attached tasks ++ * before cpus_mask may be changed. ++ */ ++ if (p->flags & PF_NO_SETAFFINITY) ++ ret = -EINVAL; ++ ++ return ret; ++} ++ ++static bool sched_smp_initialized __read_mostly; ++ ++#ifdef CONFIG_NO_HZ_COMMON ++void nohz_balance_enter_idle(int cpu) ++{ ++} ++ ++void select_nohz_load_balancer(int stop_tick) ++{ ++} ++ ++void set_cpu_sd_state_idle(void) {} ++ ++/* ++ * In the semi idle case, use the nearest busy CPU for migrating timers ++ * from an idle CPU. This is good for power-savings. ++ * ++ * We don't do similar optimization for completely idle system, as ++ * selecting an idle CPU will add more delays to the timers than intended ++ * (as that CPU's timer base may not be uptodate wrt jiffies etc). ++ */ ++int get_nohz_timer_target(void) ++{ ++ int i, cpu = smp_processor_id(), default_cpu = -1; ++ struct cpumask *mask; ++ ++ if (housekeeping_cpu(cpu, HK_FLAG_TIMER)) { ++ if (!idle_cpu(cpu)) ++ return cpu; ++ default_cpu = cpu; ++ } ++ ++ for (mask = &(per_cpu(sched_cpu_affinity_chk_masks, cpu)[0]); ++ mask < per_cpu(sched_cpu_affinity_chk_end_masks, cpu); mask++) ++ for_each_cpu_and(i, mask, housekeeping_cpumask(HK_FLAG_TIMER)) ++ if (!idle_cpu(i)) ++ return i; ++ ++ if (default_cpu == -1) ++ default_cpu = housekeeping_any_cpu(HK_FLAG_TIMER); ++ cpu = default_cpu; ++ ++ return cpu; ++} ++ ++/* ++ * When add_timer_on() enqueues a timer into the timer wheel of an ++ * idle CPU then this timer might expire before the next timer event ++ * which is scheduled to wake up that CPU. In case of a completely ++ * idle system the next event might even be infinite time into the ++ * future. wake_up_idle_cpu() ensures that the CPU is woken up and ++ * leaves the inner idle loop so the newly added timer is taken into ++ * account when the CPU goes back to idle and evaluates the timer ++ * wheel for the next timer event. ++ */ ++void wake_up_idle_cpu(int cpu) ++{ ++ struct rq *rq = cpu_rq(cpu); ++ ++ if (cpu == smp_processor_id()) ++ return; ++ ++ if (set_nr_and_not_polling(rq->idle)) ++ smp_send_reschedule(cpu); ++ else ++ trace_sched_wake_idle_without_ipi(cpu); ++} ++ ++void wake_up_nohz_cpu(int cpu) ++{ ++ wake_up_idle_cpu(cpu); ++} ++#endif /* CONFIG_NO_HZ_COMMON */ ++ ++#ifdef CONFIG_HOTPLUG_CPU ++/* ++ * Ensures that the idle task is using init_mm right before its CPU goes ++ * offline. ++ */ ++void idle_task_exit(void) ++{ ++ struct mm_struct *mm = current->active_mm; ++ ++ BUG_ON(current != this_rq()->idle); ++ ++ if (mm != &init_mm) { ++ switch_mm(mm, &init_mm, current); ++ finish_arch_post_lock_switch(); ++ } ++ ++ /* finish_cpu(), as ran on the BP, will clean up the active_mm state */ ++} ++ ++/* ++ * Migrate all tasks from the rq, sleeping tasks will be migrated by ++ * try_to_wake_up()->select_task_rq(). ++ * ++ * Called with rq->lock held even though we'er in stop_machine() and ++ * there's no concurrency possible, we hold the required locks anyway ++ * because of lock validation efforts. ++ */ ++static void migrate_tasks(struct rq *dead_rq) ++{ ++ struct rq *rq = dead_rq; ++ struct task_struct *p, *stop = rq->stop; ++ struct skiplist_node *node; ++ int count = 0; ++ ++ /* ++ * Fudge the rq selection such that the below task selection loop ++ * doesn't get stuck on the currently eligible stop task. ++ * ++ * We're currently inside stop_machine() and the rq is either stuck ++ * in the stop_machine_cpu_stop() loop, or we're executing this code, ++ * either way we should never end up calling schedule() until we're ++ * done here. ++ */ ++ rq->stop = NULL; ++ ++ node = &rq->sl_header; ++ while ((node = node->next[0]) != &rq->sl_header) { ++ int dest_cpu; ++ ++ p = skiplist_entry(node, struct task_struct, sl_node); ++ ++ /* skip the running task */ ++ if (task_running(p)) ++ continue; ++ ++ /* ++ * Rules for changing task_struct::cpus_mask are holding ++ * both pi_lock and rq->lock, such that holding either ++ * stabilizes the mask. ++ * ++ * Drop rq->lock is not quite as disastrous as it usually is ++ * because !cpu_active at this point, which means load-balance ++ * will not interfere. Also, stop-machine. ++ */ ++ raw_spin_unlock(&rq->lock); ++ raw_spin_lock(&p->pi_lock); ++ raw_spin_lock(&rq->lock); ++ ++ /* ++ * Since we're inside stop-machine, _nothing_ should have ++ * changed the task, WARN if weird stuff happened, because in ++ * that case the above rq->lock drop is a fail too. ++ */ ++ if (WARN_ON(task_rq(p) != rq || !task_on_rq_queued(p))) { ++ raw_spin_unlock(&p->pi_lock); ++ continue; ++ } ++ ++ count++; ++ /* Find suitable destination for @next, with force if needed. */ ++ dest_cpu = select_fallback_rq(dead_rq->cpu, p); ++ ++ rq = __migrate_task(rq, p, dest_cpu); ++ raw_spin_unlock(&rq->lock); ++ raw_spin_unlock(&p->pi_lock); ++ ++ rq = dead_rq; ++ raw_spin_lock(&rq->lock); ++ /* Check queued task all over from the header again */ ++ node = &rq->sl_header; ++ } ++ ++ rq->stop = stop; ++} ++ ++static void set_rq_offline(struct rq *rq) ++{ ++ if (rq->online) ++ rq->online = false; ++} ++#endif /* CONFIG_HOTPLUG_CPU */ ++ ++static void set_rq_online(struct rq *rq) ++{ ++ if (!rq->online) ++ rq->online = true; ++} ++ ++#ifdef CONFIG_SCHED_DEBUG ++ ++static __read_mostly int sched_debug_enabled; ++ ++static int __init sched_debug_setup(char *str) ++{ ++ sched_debug_enabled = 1; ++ ++ return 0; ++} ++early_param("sched_debug", sched_debug_setup); ++ ++static inline bool sched_debug(void) ++{ ++ return sched_debug_enabled; ++} ++#else /* !CONFIG_SCHED_DEBUG */ ++static inline bool sched_debug(void) ++{ ++ return false; ++} ++#endif /* CONFIG_SCHED_DEBUG */ ++ ++#ifdef CONFIG_SMP ++void send_call_function_single_ipi(int cpu) ++{ ++ struct rq *rq = cpu_rq(cpu); ++ ++ if (!set_nr_if_polling(rq->idle)) ++ arch_send_call_function_single_ipi(cpu); ++ else ++ trace_sched_wake_idle_without_ipi(cpu); ++} ++ ++void sched_ttwu_pending(void *arg) ++{ ++ struct llist_node *llist = arg; ++ struct rq *rq = this_rq(); ++ struct task_struct *p, *t; ++ struct rq_flags rf; ++ ++ if (!llist) ++ return; ++ ++ /* ++ * rq::ttwu_pending racy indication of out-standing wakeups. ++ * Races such that false-negatives are possible, since they ++ * are shorter lived that false-positives would be. ++ */ ++ WRITE_ONCE(rq->ttwu_pending, 0); ++ ++ rq_lock_irqsave(rq, &rf); ++ update_rq_clock(rq); ++ ++ /*llist_for_each_entry_safe(p, t, llist, wake_entry) ++ ttwu_do_activate(rq, p, p->sched_remote_wakeup ? WF_MIGRATED : 0, &rf);*/ ++ ++ rq_unlock_irqrestore(rq, &rf); ++} ++ ++void wake_up_if_idle(int cpu) ++{ ++ struct rq *rq = cpu_rq(cpu); ++ unsigned long flags; ++ ++ rcu_read_lock(); ++ ++ if (!is_idle_task(rcu_dereference(rq->curr))) ++ goto out; ++ ++ if (set_nr_if_polling(rq->idle)) { ++ trace_sched_wake_idle_without_ipi(cpu); ++ } else { ++ raw_spin_lock_irqsave(&rq->lock, flags); ++ if (is_idle_task(rq->curr)) ++ smp_send_reschedule(cpu); ++ /* Else CPU is not idle, do nothing here */ ++ raw_spin_unlock_irqrestore(&rq->lock, flags); ++ } ++ ++out: ++ rcu_read_unlock(); ++} ++ ++bool cpus_share_cache(int this_cpu, int that_cpu) ++{ ++ return per_cpu(sd_llc_id, this_cpu) == per_cpu(sd_llc_id, that_cpu); ++} ++#else /* !CONFIG_SMP */ ++ ++static inline bool ttwu_queue_wakelist(struct task_struct *p, int cpu, int wake_flags) ++{ ++ return false; ++} ++ ++#endif /* CONFIG_SMP */ ++ ++/* ++ * Topology list, bottom-up. ++ */ ++static struct sched_domain_topology_level default_topology[] = { ++#ifdef CONFIG_SCHED_SMT ++ { cpu_smt_mask, cpu_smt_flags, SD_INIT_NAME(SMT) }, ++#endif ++#ifdef CONFIG_SCHED_MC ++ { cpu_coregroup_mask, cpu_core_flags, SD_INIT_NAME(MC) }, ++#endif ++ { cpu_cpu_mask, SD_INIT_NAME(DIE) }, ++ { NULL, }, ++}; ++ ++static struct sched_domain_topology_level *sched_domain_topology = ++ default_topology; ++ ++#define for_each_sd_topology(tl) \ ++ for (tl = sched_domain_topology; tl->mask; tl++) ++ ++void set_sched_topology(struct sched_domain_topology_level *tl) ++{ ++ if (WARN_ON_ONCE(sched_smp_initialized)) ++ return; ++ ++ sched_domain_topology = tl; ++} ++ ++/* ++ * Initializers for schedule domains ++ * Non-inlined to reduce accumulated stack pressure in build_sched_domains() ++ */ ++ ++int sched_domain_level_max; ++ ++/* ++ * Partition sched domains as specified by the 'ndoms_new' ++ * cpumasks in the array doms_new[] of cpumasks. This compares ++ * doms_new[] to the current sched domain partitioning, doms_cur[]. ++ * It destroys each deleted domain and builds each new domain. ++ * ++ * 'doms_new' is an array of cpumask_var_t's of length 'ndoms_new'. ++ * The masks don't intersect (don't overlap.) We should setup one ++ * sched domain for each mask. CPUs not in any of the cpumasks will ++ * not be load balanced. If the same cpumask appears both in the ++ * current 'doms_cur' domains and in the new 'doms_new', we can leave ++ * it as it is. ++ * ++ * The passed in 'doms_new' should be allocated using ++ * alloc_sched_domains. This routine takes ownership of it and will ++ * free_sched_domains it when done with it. If the caller failed the ++ * alloc call, then it can pass in doms_new == NULL && ndoms_new == 1, ++ * and partition_sched_domains() will fallback to the single partition ++ * 'fallback_doms', it also forces the domains to be rebuilt. ++ * ++ * If doms_new == NULL it will be replaced with cpu_online_mask. ++ * ndoms_new == 0 is a special case for destroying existing domains, ++ * and it will not create the default domain. ++ * ++ * Call with hotplug lock held ++ */ ++void partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[], ++ struct sched_domain_attr *dattr_new) ++{ ++ /** ++ * PDS doesn't depend on sched domains, but just keep this api ++ */ ++} ++ ++/* ++ * used to mark begin/end of suspend/resume: ++ */ ++static int num_cpus_frozen; ++ ++#ifdef CONFIG_NUMA ++int __read_mostly node_reclaim_distance = RECLAIM_DISTANCE; ++ ++/* ++ * sched_numa_find_closest() - given the NUMA topology, find the cpu ++ * closest to @cpu from @cpumask. ++ * cpumask: cpumask to find a cpu from ++ * cpu: cpu to be close to ++ * ++ * returns: cpu, or nr_cpu_ids when nothing found. ++ */ ++int sched_numa_find_closest(const struct cpumask *cpus, int cpu) ++{ ++ return best_mask_cpu(cpu, cpus); ++} ++#endif /* CONFIG_NUMA */ ++ ++/* ++ * Update cpusets according to cpu_active mask. If cpusets are ++ * disabled, cpuset_update_active_cpus() becomes a simple wrapper ++ * around partition_sched_domains(). ++ * ++ * If we come here as part of a suspend/resume, don't touch cpusets because we ++ * want to restore it back to its original state upon resume anyway. ++ */ ++static void cpuset_cpu_active(void) ++{ ++ if (cpuhp_tasks_frozen) { ++ /* ++ * num_cpus_frozen tracks how many CPUs are involved in suspend ++ * resume sequence. As long as this is not the last online ++ * operation in the resume sequence, just build a single sched ++ * domain, ignoring cpusets. ++ */ ++ partition_sched_domains(1, NULL, NULL); ++ if (--num_cpus_frozen) ++ return; ++ /* ++ * This is the last CPU online operation. So fall through and ++ * restore the original sched domains by considering the ++ * cpuset configurations. ++ */ ++ cpuset_force_rebuild(); ++ } ++ ++ cpuset_update_active_cpus(); ++} ++ ++static int cpuset_cpu_inactive(unsigned int cpu) ++{ ++ if (!cpuhp_tasks_frozen) { ++ cpuset_update_active_cpus(); ++ } else { ++ num_cpus_frozen++; ++ partition_sched_domains(1, NULL, NULL); ++ } ++ return 0; ++} ++ ++int sched_cpu_activate(unsigned int cpu) ++{ ++ struct rq *rq = cpu_rq(cpu); ++ unsigned long flags; ++ ++#ifdef CONFIG_SCHED_SMT ++ /* ++ * When going up, increment the number of cores with SMT present. ++ */ ++ if (cpumask_weight(cpu_smt_mask(cpu)) == 2) ++ static_branch_inc_cpuslocked(&sched_smt_present); ++#endif ++ set_cpu_active(cpu, true); ++ ++ if (sched_smp_initialized) ++ cpuset_cpu_active(); ++ ++ /* ++ * Put the rq online, if not already. This happens: ++ * ++ * 1) In the early boot process, because we build the real domains ++ * after all cpus have been brought up. ++ * ++ * 2) At runtime, if cpuset_cpu_active() fails to rebuild the ++ * domains. ++ */ ++ raw_spin_lock_irqsave(&rq->lock, flags); ++ set_rq_online(rq); ++ raw_spin_unlock_irqrestore(&rq->lock, flags); ++ ++ return 0; ++} ++ ++int sched_cpu_deactivate(unsigned int cpu) ++{ ++ int ret; ++ ++ set_cpu_active(cpu, false); ++ /* ++ * We've cleared cpu_active_mask, wait for all preempt-disabled and RCU ++ * users of this state to go away such that all new such users will ++ * observe it. ++ * ++ * Do sync before park smpboot threads to take care the rcu boost case. ++ */ ++ synchronize_rcu(); ++ ++#ifdef CONFIG_SCHED_SMT ++ /* ++ * When going down, decrement the number of cores with SMT present. ++ */ ++ if (cpumask_weight(cpu_smt_mask(cpu)) == 2) ++ static_branch_dec_cpuslocked(&sched_smt_present); ++#endif ++ ++ if (!sched_smp_initialized) ++ return 0; ++ ++ ret = cpuset_cpu_inactive(cpu); ++ if (ret) { ++ set_cpu_active(cpu, true); ++ return ret; ++ } ++ return 0; ++} ++ ++static void sched_rq_cpu_starting(unsigned int cpu) ++{ ++ struct rq *rq = cpu_rq(cpu); ++ ++ rq->calc_load_update = calc_load_update; ++} ++ ++int sched_cpu_starting(unsigned int cpu) ++{ ++ sched_rq_cpu_starting(cpu); ++ sched_tick_start(cpu); ++ return 0; ++} ++ ++#ifdef CONFIG_HOTPLUG_CPU ++int sched_cpu_dying(unsigned int cpu) ++{ ++ struct rq *rq = cpu_rq(cpu); ++ unsigned long flags; ++ ++ sched_tick_stop(cpu); ++ raw_spin_lock_irqsave(&rq->lock, flags); ++ set_rq_offline(rq); ++ migrate_tasks(rq); ++ raw_spin_unlock_irqrestore(&rq->lock, flags); ++ ++ hrtick_clear(rq); ++ return 0; ++} ++#endif ++ ++#ifdef CONFIG_SMP ++static void sched_init_topology_cpumask_early(void) ++{ ++ int cpu, level; ++ cpumask_t *tmp; ++ ++ for_each_possible_cpu(cpu) { ++ for (level = 0; level < NR_CPU_AFFINITY_CHK_LEVEL; level++) { ++ tmp = &(per_cpu(sched_cpu_affinity_chk_masks, cpu)[level]); ++ cpumask_copy(tmp, cpu_possible_mask); ++ cpumask_clear_cpu(cpu, tmp); ++ } ++ per_cpu(sched_cpu_llc_start_mask, cpu) = ++ &(per_cpu(sched_cpu_affinity_chk_masks, cpu)[0]); ++ per_cpu(sched_cpu_affinity_chk_end_masks, cpu) = ++ &(per_cpu(sched_cpu_affinity_chk_masks, cpu)[1]); ++ } ++} ++ ++static void sched_init_topology_cpumask(void) ++{ ++ int cpu; ++ cpumask_t *chk; ++ ++ for_each_online_cpu(cpu) { ++ chk = &(per_cpu(sched_cpu_affinity_chk_masks, cpu)[0]); ++ ++#ifdef CONFIG_SCHED_SMT ++ cpumask_setall(chk); ++ cpumask_clear_cpu(cpu, chk); ++ if (cpumask_and(chk, chk, topology_sibling_cpumask(cpu))) { ++ per_cpu(sched_sibling_cpu, cpu) = cpumask_first(chk); ++ printk(KERN_INFO "pds: cpu #%d affinity check mask - smt 0x%08lx", ++ cpu, (chk++)->bits[0]); ++ } ++#endif ++#ifdef CONFIG_SCHED_MC ++ cpumask_setall(chk); ++ cpumask_clear_cpu(cpu, chk); ++ if (cpumask_and(chk, chk, cpu_coregroup_mask(cpu))) { ++ per_cpu(sched_cpu_llc_start_mask, cpu) = chk; ++ printk(KERN_INFO "pds: cpu #%d affinity check mask - coregroup 0x%08lx", ++ cpu, (chk++)->bits[0]); ++ } ++ cpumask_complement(chk, cpu_coregroup_mask(cpu)); ++ ++ /** ++ * Set up sd_llc_id per CPU ++ */ ++ per_cpu(sd_llc_id, cpu) = ++ cpumask_first(cpu_coregroup_mask(cpu)); ++#else ++ per_cpu(sd_llc_id, cpu) = ++ cpumask_first(topology_core_cpumask(cpu)); ++ ++ per_cpu(sched_cpu_llc_start_mask, cpu) = chk; ++ ++ cpumask_setall(chk); ++ cpumask_clear_cpu(cpu, chk); ++#endif /* NOT CONFIG_SCHED_MC */ ++ if (cpumask_and(chk, chk, topology_core_cpumask(cpu))) ++ printk(KERN_INFO "pds: cpu #%d affinity check mask - core 0x%08lx", ++ cpu, (chk++)->bits[0]); ++ cpumask_complement(chk, topology_core_cpumask(cpu)); ++ ++ if (cpumask_and(chk, chk, cpu_online_mask)) ++ printk(KERN_INFO "pds: cpu #%d affinity check mask - others 0x%08lx", ++ cpu, (chk++)->bits[0]); ++ ++ per_cpu(sched_cpu_affinity_chk_end_masks, cpu) = chk; ++ } ++} ++#endif ++ ++void __init sched_init_smp(void) ++{ ++ /* Move init over to a non-isolated CPU */ ++ if (set_cpus_allowed_ptr(current, housekeeping_cpumask(HK_FLAG_DOMAIN)) < 0) ++ BUG(); ++ ++ cpumask_copy(&sched_rq_queued_masks[SCHED_RQ_EMPTY], cpu_online_mask); ++ ++ sched_init_topology_cpumask(); ++ ++ sched_smp_initialized = true; ++} ++#else ++void __init sched_init_smp(void) ++{ ++} ++#endif /* CONFIG_SMP */ ++ ++int in_sched_functions(unsigned long addr) ++{ ++ return in_lock_functions(addr) || ++ (addr >= (unsigned long)__sched_text_start ++ && addr < (unsigned long)__sched_text_end); ++} ++ ++#ifdef CONFIG_CGROUP_SCHED ++/* task group related information */ ++struct task_group { ++ struct cgroup_subsys_state css; ++ ++ struct rcu_head rcu; ++ struct list_head list; ++ ++ struct task_group *parent; ++ struct list_head siblings; ++ struct list_head children; ++}; ++ ++/* ++ * Default task group. ++ * Every task in system belongs to this group at bootup. ++ */ ++struct task_group root_task_group; ++LIST_HEAD(task_groups); ++ ++/* Cacheline aligned slab cache for task_group */ ++static struct kmem_cache *task_group_cache __read_mostly; ++#endif /* CONFIG_CGROUP_SCHED */ ++ ++void __init sched_init(void) ++{ ++ int i; ++ struct rq *rq; ++ ++ print_scheduler_version(); ++ ++ wait_bit_init(); ++ ++#ifdef CONFIG_SMP ++ for (i = 0; i < NR_SCHED_RQ_QUEUED_LEVEL; i++) ++ cpumask_clear(&sched_rq_queued_masks[i]); ++ cpumask_setall(&sched_rq_queued_masks[SCHED_RQ_EMPTY]); ++ set_bit(SCHED_RQ_EMPTY, sched_rq_queued_masks_bitmap); ++ ++ cpumask_setall(&sched_rq_pending_masks[SCHED_RQ_EMPTY]); ++ set_bit(SCHED_RQ_EMPTY, sched_rq_pending_masks_bitmap); ++#else ++ uprq = &per_cpu(runqueues, 0); ++#endif ++ ++#ifdef CONFIG_CGROUP_SCHED ++ task_group_cache = KMEM_CACHE(task_group, 0); ++ ++ list_add(&root_task_group.list, &task_groups); ++ INIT_LIST_HEAD(&root_task_group.children); ++ INIT_LIST_HEAD(&root_task_group.siblings); ++#endif /* CONFIG_CGROUP_SCHED */ ++ for_each_possible_cpu(i) { ++ rq = cpu_rq(i); ++ FULL_INIT_SKIPLIST_NODE(&rq->sl_header); ++ raw_spin_lock_init(&rq->lock); ++ rq->dither = 0; ++ rq->nr_running = rq->nr_uninterruptible = 0; ++ rq->calc_load_active = 0; ++ rq->calc_load_update = jiffies + LOAD_FREQ; ++#ifdef CONFIG_SMP ++ rq->online = false; ++ rq->cpu = i; ++ ++ rq->queued_level = SCHED_RQ_EMPTY; ++ rq->pending_level = SCHED_RQ_EMPTY; ++#ifdef CONFIG_SCHED_SMT ++ per_cpu(sched_sibling_cpu, i) = i; ++ rq->active_balance = 0; ++#endif ++#endif ++ rq->nr_switches = 0; ++ atomic_set(&rq->nr_iowait, 0); ++ hrtick_rq_init(rq); ++ } ++#ifdef CONFIG_SMP ++ /* Set rq->online for cpu 0 */ ++ cpu_rq(0)->online = true; ++#endif ++ ++ /* ++ * The boot idle thread does lazy MMU switching as well: ++ */ ++ mmgrab(&init_mm); ++ enter_lazy_tlb(&init_mm, current); ++ ++ /* ++ * Make us the idle thread. Technically, schedule() should not be ++ * called from this thread, however somewhere below it might be, ++ * but because we are the idle thread, we just pick up running again ++ * when this runqueue becomes "idle". ++ */ ++ init_idle(current, smp_processor_id()); ++ ++ calc_load_update = jiffies + LOAD_FREQ; ++ ++#ifdef CONFIG_SMP ++ idle_thread_set_boot_cpu(); ++ ++ sched_init_topology_cpumask_early(); ++#endif /* SMP */ ++ ++ init_schedstats(); ++ ++ psi_init(); ++} ++ ++#ifdef CONFIG_DEBUG_ATOMIC_SLEEP ++static inline int preempt_count_equals(int preempt_offset) ++{ ++ int nested = preempt_count() + rcu_preempt_depth(); ++ ++ return (nested == preempt_offset); ++} ++ ++void __might_sleep(const char *file, int line, int preempt_offset) ++{ ++ /* ++ * Blocking primitives will set (and therefore destroy) current->state, ++ * since we will exit with TASK_RUNNING make sure we enter with it, ++ * otherwise we will destroy state. ++ */ ++ WARN_ONCE(current->state != TASK_RUNNING && current->task_state_change, ++ "do not call blocking ops when !TASK_RUNNING; " ++ "state=%lx set at [<%p>] %pS\n", ++ current->state, ++ (void *)current->task_state_change, ++ (void *)current->task_state_change); ++ ++ ___might_sleep(file, line, preempt_offset); ++} ++EXPORT_SYMBOL(__might_sleep); ++ ++void ___might_sleep(const char *file, int line, int preempt_offset) ++{ ++ /* Ratelimiting timestamp: */ ++ static unsigned long prev_jiffy; ++ ++ unsigned long preempt_disable_ip; ++ ++ /* WARN_ON_ONCE() by default, no rate limit required: */ ++ rcu_sleep_check(); ++ ++ if ((preempt_count_equals(preempt_offset) && !irqs_disabled() && ++ !is_idle_task(current) && !current->non_block_count) || ++ system_state == SYSTEM_BOOTING || system_state > SYSTEM_RUNNING || ++ oops_in_progress) ++ return; ++ if (time_before(jiffies, prev_jiffy + HZ) && prev_jiffy) ++ return; ++ prev_jiffy = jiffies; ++ ++ /* Save this before calling printk(), since that will clobber it: */ ++ preempt_disable_ip = get_preempt_disable_ip(current); ++ ++ printk(KERN_ERR ++ "BUG: sleeping function called from invalid context at %s:%d\n", ++ file, line); ++ printk(KERN_ERR ++ "in_atomic(): %d, irqs_disabled(): %d, non_block: %d, pid: %d, name: %s\n", ++ in_atomic(), irqs_disabled(), current->non_block_count, ++ current->pid, current->comm); ++ ++ if (task_stack_end_corrupted(current)) ++ printk(KERN_EMERG "Thread overran stack, or stack corrupted\n"); ++ ++ debug_show_held_locks(current); ++ if (irqs_disabled()) ++ print_irqtrace_events(current); ++#ifdef CONFIG_DEBUG_PREEMPT ++ if (!preempt_count_equals(preempt_offset)) { ++ pr_err("Preemption disabled at:"); ++ print_ip_sym(KERN_ERR, preempt_disable_ip); ++ } ++#endif ++ dump_stack(); ++ add_taint(TAINT_WARN, LOCKDEP_STILL_OK); ++} ++EXPORT_SYMBOL(___might_sleep); ++ ++void __cant_sleep(const char *file, int line, int preempt_offset) ++{ ++ static unsigned long prev_jiffy; ++ ++ if (irqs_disabled()) ++ return; ++ ++ if (!IS_ENABLED(CONFIG_PREEMPT_COUNT)) ++ return; ++ ++ if (preempt_count() > preempt_offset) ++ return; ++ ++ if (time_before(jiffies, prev_jiffy + HZ) && prev_jiffy) ++ return; ++ prev_jiffy = jiffies; ++ ++ printk(KERN_ERR "BUG: assuming atomic context at %s:%d\n", file, line); ++ printk(KERN_ERR "in_atomic(): %d, irqs_disabled(): %d, pid: %d, name: %s\n", ++ in_atomic(), irqs_disabled(), ++ current->pid, current->comm); ++ ++ debug_show_held_locks(current); ++ dump_stack(); ++ add_taint(TAINT_WARN, LOCKDEP_STILL_OK); ++} ++EXPORT_SYMBOL_GPL(__cant_sleep); ++#endif ++ ++#ifdef CONFIG_MAGIC_SYSRQ ++void normalize_rt_tasks(void) ++{ ++ struct task_struct *g, *p; ++ struct sched_attr attr = { ++ .sched_policy = SCHED_NORMAL, ++ }; ++ ++ read_lock(&tasklist_lock); ++ for_each_process_thread(g, p) { ++ /* ++ * Only normalize user tasks: ++ */ ++ if (p->flags & PF_KTHREAD) ++ continue; ++ ++ if (!rt_task(p)) { ++ /* ++ * Renice negative nice level userspace ++ * tasks back to 0: ++ */ ++ if (task_nice(p) < 0) ++ set_user_nice(p, 0); ++ continue; ++ } ++ ++ __sched_setscheduler(p, &attr, false, false); ++ } ++ read_unlock(&tasklist_lock); ++} ++#endif /* CONFIG_MAGIC_SYSRQ */ ++ ++#if defined(CONFIG_IA64) || defined(CONFIG_KGDB_KDB) ++/* ++ * These functions are only useful for the IA64 MCA handling, or kdb. ++ * ++ * They can only be called when the whole system has been ++ * stopped - every CPU needs to be quiescent, and no scheduling ++ * activity can take place. Using them for anything else would ++ * be a serious bug, and as a result, they aren't even visible ++ * under any other configuration. ++ */ ++ ++/** ++ * curr_task - return the current task for a given CPU. ++ * @cpu: the processor in question. ++ * ++ * ONLY VALID WHEN THE WHOLE SYSTEM IS STOPPED! ++ * ++ * Return: The current task for @cpu. ++ */ ++struct task_struct *curr_task(int cpu) ++{ ++ return cpu_curr(cpu); ++} ++ ++#endif /* defined(CONFIG_IA64) || defined(CONFIG_KGDB_KDB) */ ++ ++#ifdef CONFIG_IA64 ++/** ++ * ia64_set_curr_task - set the current task for a given CPU. ++ * @cpu: the processor in question. ++ * @p: the task pointer to set. ++ * ++ * Description: This function must only be used when non-maskable interrupts ++ * are serviced on a separate stack. It allows the architecture to switch the ++ * notion of the current task on a CPU in a non-blocking manner. This function ++ * must be called with all CPU's synchronised, and interrupts disabled, the ++ * and caller must save the original value of the current task (see ++ * curr_task() above) and restore that value before reenabling interrupts and ++ * re-starting the system. ++ * ++ * ONLY VALID WHEN THE WHOLE SYSTEM IS STOPPED! ++ */ ++void ia64_set_curr_task(int cpu, struct task_struct *p) ++{ ++ cpu_curr(cpu) = p; ++} ++ ++#endif ++ ++#ifdef CONFIG_SCHED_DEBUG ++void proc_sched_show_task(struct task_struct *p, struct pid_namespace *ns, ++ struct seq_file *m) ++{} ++ ++void proc_sched_set_task(struct task_struct *p) ++{} ++#endif ++ ++#ifdef CONFIG_CGROUP_SCHED ++static void sched_free_group(struct task_group *tg) ++{ ++ kmem_cache_free(task_group_cache, tg); ++} ++ ++/* allocate runqueue etc for a new task group */ ++struct task_group *sched_create_group(struct task_group *parent) ++{ ++ struct task_group *tg; ++ ++ tg = kmem_cache_alloc(task_group_cache, GFP_KERNEL | __GFP_ZERO); ++ if (!tg) ++ return ERR_PTR(-ENOMEM); ++ ++ return tg; ++} ++ ++void sched_online_group(struct task_group *tg, struct task_group *parent) ++{ ++} ++ ++/* rcu callback to free various structures associated with a task group */ ++static void sched_free_group_rcu(struct rcu_head *rhp) ++{ ++ /* Now it should be safe to free those cfs_rqs */ ++ sched_free_group(container_of(rhp, struct task_group, rcu)); ++} ++ ++void sched_destroy_group(struct task_group *tg) ++{ ++ /* Wait for possible concurrent references to cfs_rqs complete */ ++ call_rcu(&tg->rcu, sched_free_group_rcu); ++} ++ ++void sched_offline_group(struct task_group *tg) ++{ ++} ++ ++static inline struct task_group *css_tg(struct cgroup_subsys_state *css) ++{ ++ return css ? container_of(css, struct task_group, css) : NULL; ++} ++ ++static struct cgroup_subsys_state * ++cpu_cgroup_css_alloc(struct cgroup_subsys_state *parent_css) ++{ ++ struct task_group *parent = css_tg(parent_css); ++ struct task_group *tg; ++ ++ if (!parent) { ++ /* This is early initialization for the top cgroup */ ++ return &root_task_group.css; ++ } ++ ++ tg = sched_create_group(parent); ++ if (IS_ERR(tg)) ++ return ERR_PTR(-ENOMEM); ++ return &tg->css; ++} ++ ++/* Expose task group only after completing cgroup initialization */ ++static int cpu_cgroup_css_online(struct cgroup_subsys_state *css) ++{ ++ struct task_group *tg = css_tg(css); ++ struct task_group *parent = css_tg(css->parent); ++ ++ if (parent) ++ sched_online_group(tg, parent); ++ return 0; ++} ++ ++static void cpu_cgroup_css_released(struct cgroup_subsys_state *css) ++{ ++ struct task_group *tg = css_tg(css); ++ ++ sched_offline_group(tg); ++} ++ ++static void cpu_cgroup_css_free(struct cgroup_subsys_state *css) ++{ ++ struct task_group *tg = css_tg(css); ++ ++ /* ++ * Relies on the RCU grace period between css_released() and this. ++ */ ++ sched_free_group(tg); ++} ++ ++static void cpu_cgroup_fork(struct task_struct *task) ++{ ++} ++ ++static int cpu_cgroup_can_attach(struct cgroup_taskset *tset) ++{ ++ return 0; ++} ++ ++static void cpu_cgroup_attach(struct cgroup_taskset *tset) ++{ ++} ++ ++static struct cftype cpu_legacy_files[] = { ++ { } /* Terminate */ ++}; ++ ++static struct cftype cpu_files[] = { ++ { } /* terminate */ ++}; ++ ++static int cpu_extra_stat_show(struct seq_file *sf, ++ struct cgroup_subsys_state *css) ++{ ++ return 0; ++} ++ ++struct cgroup_subsys cpu_cgrp_subsys = { ++ .css_alloc = cpu_cgroup_css_alloc, ++ .css_online = cpu_cgroup_css_online, ++ .css_released = cpu_cgroup_css_released, ++ .css_free = cpu_cgroup_css_free, ++ .css_extra_stat_show = cpu_extra_stat_show, ++ .fork = cpu_cgroup_fork, ++ .can_attach = cpu_cgroup_can_attach, ++ .attach = cpu_cgroup_attach, ++ .legacy_cftypes = cpu_files, ++ .legacy_cftypes = cpu_legacy_files, ++ .dfl_cftypes = cpu_files, ++ .early_init = true, ++ .threaded = true, ++}; ++#endif /* CONFIG_CGROUP_SCHED */ ++ ++#undef CREATE_TRACE_POINTS +diff --git a/kernel/sched/pds_sched.h b/kernel/sched/pds_sched.h +new file mode 100644 +index 000000000000..0a2e8b145ae1 +--- /dev/null ++++ b/kernel/sched/pds_sched.h +@@ -0,0 +1,581 @@ ++#ifndef PDS_SCHED_H ++#define PDS_SCHED_H ++ ++#include ++ ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++ ++#include ++ ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++ ++#include ++ ++#ifdef CONFIG_PARAVIRT ++# include ++#endif ++ ++#include "cpupri.h" ++ ++#include ++ ++/* task_struct::on_rq states: */ ++#define TASK_ON_RQ_QUEUED 1 ++#define TASK_ON_RQ_MIGRATING 2 ++ ++static inline int task_on_rq_queued(struct task_struct *p) ++{ ++ return p->on_rq == TASK_ON_RQ_QUEUED; ++} ++ ++static inline int task_on_rq_migrating(struct task_struct *p) ++{ ++ return READ_ONCE(p->on_rq) == TASK_ON_RQ_MIGRATING; ++} ++ ++/* ++ * wake flags ++ */ ++#define WF_SYNC 0x01 /* waker goes to sleep after wakeup */ ++#define WF_FORK 0x02 /* child wakeup after fork */ ++#define WF_MIGRATED 0x04 /* internal use, task got migrated */ ++ ++/* ++ * rq::clock_update_flags bits ++ */ ++#define RQCF_REQ_SKIP 0x01 ++#define RQCF_ACT_SKIP 0x02 ++#define RQCF_UPDATED 0x04 ++ ++/* ++ * This is the main, per-CPU runqueue data structure. ++ * This data should only be modified by the local cpu. ++ */ ++struct rq { ++ /* runqueue lock: */ ++ raw_spinlock_t lock; ++ ++ struct task_struct __rcu *curr; ++ struct task_struct *idle, *stop; ++ struct mm_struct *prev_mm; ++ ++ struct skiplist_node sl_header; ++ ++ /* switch count */ ++ u64 nr_switches; ++ ++ atomic_t nr_iowait; ++ ++#ifdef CONFIG_MEMBARRIER ++ int membarrier_state; ++#endif ++ ++#ifdef CONFIG_SMP ++ int cpu; /* cpu of this runqueue */ ++ bool online; ++ unsigned int ttwu_pending; ++ unsigned int clock_update_flags; ++ ++#ifdef CONFIG_HAVE_SCHED_AVG_IRQ ++ struct sched_avg avg_irq; ++#endif ++#ifdef CONFIG_SCHED_THERMAL_PRESSURE ++ struct sched_avg avg_thermal; ++#endif ++ ++ unsigned long queued_level; ++ unsigned long pending_level; ++ ++#ifdef CONFIG_SCHED_SMT ++ int active_balance; ++ struct cpu_stop_work active_balance_work; ++#endif ++#endif /* CONFIG_SMP */ ++#ifdef CONFIG_IRQ_TIME_ACCOUNTING ++ u64 prev_irq_time; ++#endif /* CONFIG_IRQ_TIME_ACCOUNTING */ ++#ifdef CONFIG_PARAVIRT ++ u64 prev_steal_time; ++#endif /* CONFIG_PARAVIRT */ ++#ifdef CONFIG_PARAVIRT_TIME_ACCOUNTING ++ u64 prev_steal_time_rq; ++#endif /* CONFIG_PARAVIRT_TIME_ACCOUNTING */ ++ ++ /* calc_load related fields */ ++ unsigned long calc_load_update; ++ long calc_load_active; ++ ++ u64 clock, last_tick; ++ u64 clock_task; ++ int dither; ++ ++ unsigned long nr_running; ++ unsigned long nr_uninterruptible; ++ ++#ifdef CONFIG_SCHED_HRTICK ++#ifdef CONFIG_SMP ++ call_single_data_t hrtick_csd; ++#endif ++ struct hrtimer hrtick_timer; ++#endif ++ ++#ifdef CONFIG_SCHEDSTATS ++ ++ /* latency stats */ ++ struct sched_info rq_sched_info; ++ unsigned long long rq_cpu_time; ++ /* could above be rq->cfs_rq.exec_clock + rq->rt_rq.rt_runtime ? */ ++ ++ /* sys_sched_yield() stats */ ++ unsigned int yld_count; ++ ++ /* schedule() stats */ ++ unsigned int sched_switch; ++ unsigned int sched_count; ++ unsigned int sched_goidle; ++ ++ /* try_to_wake_up() stats */ ++ unsigned int ttwu_count; ++ unsigned int ttwu_local; ++#endif /* CONFIG_SCHEDSTATS */ ++#ifdef CONFIG_CPU_IDLE ++ /* Must be inspected within a rcu lock section */ ++ struct cpuidle_state *idle_state; ++#endif ++}; ++ ++#define task_contributes_to_load(task) ((task->state & TASK_UNINTERRUPTIBLE) != 0 && \ ++ (task->flags & PF_FROZEN) == 0 && \ ++ (task->state & TASK_NOLOAD) == 0) ++ ++extern unsigned long calc_load_update; ++extern atomic_long_t calc_load_tasks; ++ ++extern void calc_global_load_tick(struct rq *this_rq); ++extern long calc_load_fold_active(struct rq *this_rq, long adjust); ++ ++#ifndef CONFIG_SMP ++extern struct rq *uprq; ++#define cpu_rq(cpu) (uprq) ++#define this_rq() (uprq) ++#define raw_rq() (uprq) ++#define task_rq(p) (uprq) ++#define cpu_curr(cpu) ((uprq)->curr) ++#else /* CONFIG_SMP */ ++DECLARE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues); ++#define cpu_rq(cpu) (&per_cpu(runqueues, (cpu))) ++#define this_rq() this_cpu_ptr(&runqueues) ++#define raw_rq() raw_cpu_ptr(&runqueues) ++#define task_rq(p) cpu_rq(task_cpu(p)) ++#define cpu_curr(cpu) (cpu_rq(cpu)->curr) ++ ++#if defined(CONFIG_SCHED_DEBUG) && defined(CONFIG_SYSCTL) ++void register_sched_domain_sysctl(void); ++void unregister_sched_domain_sysctl(void); ++#else ++static inline void register_sched_domain_sysctl(void) ++{ ++} ++static inline void unregister_sched_domain_sysctl(void) ++{ ++} ++#endif ++ ++#endif /* CONFIG_SMP */ ++ ++#ifndef arch_scale_freq_tick ++static __always_inline ++void arch_scale_freq_tick(void) ++{ ++} ++#endif ++ ++#ifndef arch_scale_freq_capacity ++static __always_inline ++unsigned long arch_scale_freq_capacity(int cpu) ++{ ++ return SCHED_CAPACITY_SCALE; ++} ++#endif ++ ++static inline u64 __rq_clock_broken(struct rq *rq) ++{ ++ return READ_ONCE(rq->clock); ++} ++ ++static inline u64 rq_clock(struct rq *rq) ++{ ++ /* ++ * Relax lockdep_assert_held() checking as in VRQ, call to ++ * sched_info_xxxx() may not held rq->lock ++ * lockdep_assert_held(&rq->lock); ++ */ ++ return rq->clock; ++} ++ ++static inline u64 rq_clock_task(struct rq *rq) ++{ ++ /* ++ * Relax lockdep_assert_held() checking as in VRQ, call to ++ * sched_info_xxxx() may not held rq->lock ++ * lockdep_assert_held(&rq->lock); ++ */ ++ return rq->clock_task; ++} ++ ++/** ++ * By default the decay is the default pelt decay period. ++ * The decay shift can change the decay period in ++ * multiples of 32. ++ * Decay shift Decay period(ms) ++ * 0 32 ++ * 1 64 ++ * 2 128 ++ * 3 256 ++ * 4 512 ++ */ ++extern int sched_thermal_decay_shift; ++ ++static inline u64 rq_clock_thermal(struct rq *rq) ++{ ++ return rq_clock_task(rq) >> sched_thermal_decay_shift; ++} ++ ++/* ++ * {de,en}queue flags: ++ * ++ * DEQUEUE_SLEEP - task is no longer runnable ++ * ENQUEUE_WAKEUP - task just became runnable ++ * ++ */ ++ ++#define DEQUEUE_SLEEP 0x01 ++ ++#define ENQUEUE_WAKEUP 0x01 ++ ++ ++/* ++ * Below are scheduler API which using in other kernel code ++ * It use the dummy rq_flags ++ * ToDo : PDS need to support these APIs for compatibility with mainline ++ * scheduler code. ++ */ ++struct rq_flags { ++ unsigned long flags; ++ struct pin_cookie cookie; ++ unsigned int clock_update_flags; ++}; ++ ++struct rq *__task_rq_lock(struct task_struct *p, struct rq_flags *rf) ++ __acquires(rq->lock); ++ ++struct rq *task_rq_lock(struct task_struct *p, struct rq_flags *rf) ++ __acquires(p->pi_lock) ++ __acquires(rq->lock); ++ ++static inline void __task_rq_unlock(struct rq *rq, struct rq_flags *rf) ++ __releases(rq->lock) ++{ ++ raw_spin_unlock(&rq->lock); ++} ++ ++static inline void rq_pin_lock(struct rq *rq, struct rq_flags *rf) ++{ ++ rf->cookie = lockdep_pin_lock(&rq->lock); ++ ++#ifdef CONFIG_SCHED_DEBUG ++ rq->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP); ++ rf->clock_update_flags = 0; ++#endif ++} ++ ++static inline void rq_unpin_lock(struct rq *rq, struct rq_flags *rf) ++{ ++#ifdef CONFIG_SCHED_DEBUG ++ if (rq->clock_update_flags > RQCF_ACT_SKIP) ++ rf->clock_update_flags = RQCF_UPDATED; ++#endif ++ ++ lockdep_unpin_lock(&rq->lock, rf->cookie); ++} ++ ++static inline void ++task_rq_unlock(struct rq *rq, struct task_struct *p, struct rq_flags *rf) ++ __releases(rq->lock) ++ __releases(p->pi_lock) ++{ ++ raw_spin_unlock(&rq->lock); ++ raw_spin_unlock_irqrestore(&p->pi_lock, rf->flags); ++} ++ ++static inline void ++rq_lock_irqsave(struct rq *rq, struct rq_flags *rf) ++ __acquires(rq->lock) ++{ ++ raw_spin_lock_irqsave(&rq->lock, rf->flags); ++ rq_pin_lock(rq, rf); ++} ++ ++static inline void ++rq_unlock_irqrestore(struct rq *rq, struct rq_flags *rf) ++ __releases(rq->lock) ++{ ++ rq_unpin_lock(rq, rf); ++ raw_spin_unlock_irqrestore(&rq->lock, rf->flags); ++} ++ ++static inline void ++rq_unlock_irq(struct rq *rq, struct rq_flags *rf) ++ __releases(rq->lock) ++{ ++ raw_spin_unlock_irq(&rq->lock); ++} ++ ++static inline void ++rq_unlock(struct rq *rq, struct rq_flags *rf) ++ __releases(rq->lock) ++{ ++ rq_unpin_lock(rq, rf); ++ raw_spin_unlock(&rq->lock); ++} ++ ++static inline struct rq * ++this_rq_lock_irq(struct rq_flags *rf) ++ __acquires(rq->lock) ++{ ++ struct rq *rq; ++ ++ local_irq_disable(); ++ rq = this_rq(); ++ raw_spin_lock(&rq->lock); ++ ++ return rq; ++} ++ ++static inline int task_current(struct rq *rq, struct task_struct *p) ++{ ++ return rq->curr == p; ++} ++ ++static inline bool task_running(struct task_struct *p) ++{ ++ return p->on_cpu; ++} ++ ++extern struct static_key_false sched_schedstats; ++ ++extern void flush_smp_call_function_from_idle(void); ++ ++#ifdef CONFIG_CPU_IDLE ++static inline void idle_set_state(struct rq *rq, ++ struct cpuidle_state *idle_state) ++{ ++ rq->idle_state = idle_state; ++} ++ ++static inline struct cpuidle_state *idle_get_state(struct rq *rq) ++{ ++ WARN_ON(!rcu_read_lock_held()); ++ return rq->idle_state; ++} ++#else ++static inline void idle_set_state(struct rq *rq, ++ struct cpuidle_state *idle_state) ++{ ++} ++ ++static inline struct cpuidle_state *idle_get_state(struct rq *rq) ++{ ++ return NULL; ++} ++#endif ++ ++static inline int cpu_of(const struct rq *rq) ++{ ++#ifdef CONFIG_SMP ++ return rq->cpu; ++#else ++ return 0; ++#endif ++} ++ ++#include "stats.h" ++ ++#ifdef CONFIG_IRQ_TIME_ACCOUNTING ++struct irqtime { ++ u64 total; ++ u64 tick_delta; ++ u64 irq_start_time; ++ struct u64_stats_sync sync; ++}; ++ ++DECLARE_PER_CPU(struct irqtime, cpu_irqtime); ++ ++/* ++ * Returns the irqtime minus the softirq time computed by ksoftirqd. ++ * Otherwise ksoftirqd's sum_exec_runtime is substracted its own runtime ++ * and never move forward. ++ */ ++static inline u64 irq_time_read(int cpu) ++{ ++ struct irqtime *irqtime = &per_cpu(cpu_irqtime, cpu); ++ unsigned int seq; ++ u64 total; ++ ++ do { ++ seq = __u64_stats_fetch_begin(&irqtime->sync); ++ total = irqtime->total; ++ } while (__u64_stats_fetch_retry(&irqtime->sync, seq)); ++ ++ return total; ++} ++#endif /* CONFIG_IRQ_TIME_ACCOUNTING */ ++ ++#ifdef CONFIG_CPU_FREQ ++DECLARE_PER_CPU(struct update_util_data __rcu *, cpufreq_update_util_data); ++ ++/** ++ * cpufreq_update_util - Take a note about CPU utilization changes. ++ * @rq: Runqueue to carry out the update for. ++ * @flags: Update reason flags. ++ * ++ * This function is called by the scheduler on the CPU whose utilization is ++ * being updated. ++ * ++ * It can only be called from RCU-sched read-side critical sections. ++ * ++ * The way cpufreq is currently arranged requires it to evaluate the CPU ++ * performance state (frequency/voltage) on a regular basis to prevent it from ++ * being stuck in a completely inadequate performance level for too long. ++ * That is not guaranteed to happen if the updates are only triggered from CFS ++ * and DL, though, because they may not be coming in if only RT tasks are ++ * active all the time (or there are RT tasks only). ++ * ++ * As a workaround for that issue, this function is called periodically by the ++ * RT sched class to trigger extra cpufreq updates to prevent it from stalling, ++ * but that really is a band-aid. Going forward it should be replaced with ++ * solutions targeted more specifically at RT tasks. ++ */ ++static inline void cpufreq_update_util(struct rq *rq, unsigned int flags) ++{ ++ struct update_util_data *data; ++ ++ data = rcu_dereference_sched(*this_cpu_ptr(&cpufreq_update_util_data)); ++ if (data) ++ data->func(data, rq_clock(rq), flags); ++} ++ ++static inline void cpufreq_update_this_cpu(struct rq *rq, unsigned int flags) ++{ ++ if (cpu_of(rq) == smp_processor_id()) ++ cpufreq_update_util(rq, flags); ++} ++#else ++static inline void cpufreq_update_util(struct rq *rq, unsigned int flags) {} ++static inline void cpufreq_update_this_cpu(struct rq *rq, unsigned int flags) {} ++#endif /* CONFIG_CPU_FREQ */ ++ ++#ifdef CONFIG_NO_HZ_FULL ++extern int __init sched_tick_offload_init(void); ++#else ++static inline int sched_tick_offload_init(void) { return 0; } ++#endif ++ ++#ifdef arch_scale_freq_capacity ++#ifndef arch_scale_freq_invariant ++#define arch_scale_freq_invariant() (true) ++#endif ++#else /* arch_scale_freq_capacity */ ++#define arch_scale_freq_invariant() (false) ++#endif ++ ++extern void schedule_idle(void); ++ ++#define cap_scale(v, s) ((v)*(s) >> SCHED_CAPACITY_SHIFT) ++ ++/* ++ * !! For sched_setattr_nocheck() (kernel) only !! ++ * ++ * This is actually gross. :( ++ * ++ * It is used to make schedutil kworker(s) higher priority than SCHED_DEADLINE ++ * tasks, but still be able to sleep. We need this on platforms that cannot ++ * atomically change clock frequency. Remove once fast switching will be ++ * available on such platforms. ++ * ++ * SUGOV stands for SchedUtil GOVernor. ++ */ ++#define SCHED_FLAG_SUGOV 0x10000000 ++ ++#ifdef CONFIG_MEMBARRIER ++/* ++ * The scheduler provides memory barriers required by membarrier between: ++ * - prior user-space memory accesses and store to rq->membarrier_state, ++ * - store to rq->membarrier_state and following user-space memory accesses. ++ * In the same way it provides those guarantees around store to rq->curr. ++ */ ++static inline void membarrier_switch_mm(struct rq *rq, ++ struct mm_struct *prev_mm, ++ struct mm_struct *next_mm) ++{ ++ int membarrier_state; ++ ++ if (prev_mm == next_mm) ++ return; ++ ++ membarrier_state = atomic_read(&next_mm->membarrier_state); ++ if (READ_ONCE(rq->membarrier_state) == membarrier_state) ++ return; ++ ++ WRITE_ONCE(rq->membarrier_state, membarrier_state); ++} ++#else ++static inline void membarrier_switch_mm(struct rq *rq, ++ struct mm_struct *prev_mm, ++ struct mm_struct *next_mm) ++{ ++} ++#endif ++ ++#ifdef CONFIG_NUMA ++extern int sched_numa_find_closest(const struct cpumask *cpus, int cpu); ++#else ++static inline int sched_numa_find_closest(const struct cpumask *cpus, int cpu) ++{ ++ return nr_cpu_ids; ++} ++#endif ++ ++void swake_up_all_locked(struct swait_queue_head *q); ++void __prepare_to_swait(struct swait_queue_head *q, struct swait_queue *wait); ++ ++#endif /* PDS_SCHED_H */ +diff --git a/kernel/sched/pelt.c b/kernel/sched/pelt.c +index 2c613e1cff3a..02bef8978060 100644 +--- a/kernel/sched/pelt.c ++++ b/kernel/sched/pelt.c +@@ -270,6 +270,7 @@ ___update_load_avg(struct sched_avg *sa, unsigned long load) + WRITE_ONCE(sa->util_avg, sa->util_sum / divider); + } + ++#ifndef CONFIG_SCHED_PDS + /* + * sched_entity: + * +@@ -387,6 +388,7 @@ int update_dl_rq_load_avg(u64 now, struct rq *rq, int running) + + return 0; + } ++#endif + + #ifdef CONFIG_SCHED_THERMAL_PRESSURE + /* +diff --git a/kernel/sched/pelt.h b/kernel/sched/pelt.h +index 795e43e02afc..d1fc38858d7f 100644 +--- a/kernel/sched/pelt.h ++++ b/kernel/sched/pelt.h +@@ -1,11 +1,13 @@ + #ifdef CONFIG_SMP + #include "sched-pelt.h" + ++#ifndef CONFIG_SCHED_PDS + int __update_load_avg_blocked_se(u64 now, struct sched_entity *se); + int __update_load_avg_se(u64 now, struct cfs_rq *cfs_rq, struct sched_entity *se); + int __update_load_avg_cfs_rq(u64 now, struct cfs_rq *cfs_rq); + int update_rt_rq_load_avg(u64 now, struct rq *rq, int running); + int update_dl_rq_load_avg(u64 now, struct rq *rq, int running); ++#endif + + #ifdef CONFIG_SCHED_THERMAL_PRESSURE + int update_thermal_load_avg(u64 now, struct rq *rq, u64 capacity); +@@ -42,6 +44,7 @@ static inline u32 get_pelt_divider(struct sched_avg *avg) + return LOAD_AVG_MAX - 1024 + avg->period_contrib; + } + ++#ifndef CONFIG_SCHED_PDS + /* + * When a task is dequeued, its estimated utilization should not be update if + * its util_avg has not been updated at least once. +@@ -162,9 +165,11 @@ static inline u64 cfs_rq_clock_pelt(struct cfs_rq *cfs_rq) + return rq_clock_pelt(rq_of(cfs_rq)); + } + #endif ++#endif /* CONFIG_SCHED_PDS */ + + #else + ++#ifndef CONFIG_SCHED_PDS + static inline int + update_cfs_rq_load_avg(u64 now, struct cfs_rq *cfs_rq) + { +@@ -193,6 +198,7 @@ static inline u64 thermal_load_avg(struct rq *rq) + { + return 0; + } ++#endif + + static inline int + update_irq_load_avg(struct rq *rq, u64 running) +diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h +index 28709f6b0975..21a6c761703a 100644 +--- a/kernel/sched/sched.h ++++ b/kernel/sched/sched.h +@@ -2,6 +2,10 @@ + /* + * Scheduler internal types and methods: + */ ++#ifdef CONFIG_SCHED_PDS ++#include "pds_sched.h" ++#else ++ + #include + + #include +@@ -2626,3 +2630,5 @@ static inline bool is_per_cpu_kthread(struct task_struct *p) + + void swake_up_all_locked(struct swait_queue_head *q); + void __prepare_to_swait(struct swait_queue_head *q, struct swait_queue *wait); ++ ++#endif /* !CONFIG_SCHED_PDS */ +diff --git a/kernel/sched/stats.c b/kernel/sched/stats.c +index 750fb3c67eed..45bd43942575 100644 +--- a/kernel/sched/stats.c ++++ b/kernel/sched/stats.c +@@ -22,8 +22,10 @@ static int show_schedstat(struct seq_file *seq, void *v) + } else { + struct rq *rq; + #ifdef CONFIG_SMP ++#ifndef CONFIG_SCHED_PDS + struct sched_domain *sd; + int dcount = 0; ++#endif + #endif + cpu = (unsigned long)(v - 2); + rq = cpu_rq(cpu); +@@ -40,6 +42,7 @@ static int show_schedstat(struct seq_file *seq, void *v) + seq_printf(seq, "\n"); + + #ifdef CONFIG_SMP ++#ifndef CONFIG_SCHED_PDS + /* domain-specific stats */ + rcu_read_lock(); + for_each_domain(cpu, sd) { +@@ -68,6 +71,7 @@ static int show_schedstat(struct seq_file *seq, void *v) + sd->ttwu_move_balance); + } + rcu_read_unlock(); ++#endif + #endif + } + return 0; +diff --git a/kernel/sysctl.c b/kernel/sysctl.c +index afad085960b8..61b25c6470d4 100644 +--- a/kernel/sysctl.c ++++ b/kernel/sysctl.c +@@ -117,9 +117,13 @@ static int __maybe_unused four = 4; + static unsigned long zero_ul; + static unsigned long one_ul = 1; + static unsigned long long_max = LONG_MAX; +-static int one_hundred = 100; +-static int two_hundred = 200; +-static int one_thousand = 1000; ++static int __read_mostly one_hundred = 100; ++static int __read_mostly two_hundred = 200; ++static int __read_mostly one_thousand = 1000; ++#ifdef CONFIG_SCHED_PDS ++extern int rr_interval; ++extern int sched_yield_type; ++#endif + #ifdef CONFIG_PRINTK + static int ten_thousand = 10000; + #endif +@@ -184,7 +188,7 @@ static enum sysctl_writes_mode sysctl_writes_strict = SYSCTL_WRITES_STRICT; + int sysctl_legacy_va_layout; + #endif + +-#ifdef CONFIG_SCHED_DEBUG ++#if defined(CONFIG_SCHED_DEBUG) && !defined(CONFIG_SCHED_PDS) + static int min_sched_granularity_ns = 100000; /* 100 usecs */ + static int max_sched_granularity_ns = NSEC_PER_SEC; /* 1 second */ + static int min_wakeup_granularity_ns; /* 0 usecs */ +@@ -1652,6 +1656,7 @@ int proc_do_static_key(struct ctl_table *table, int write, + } + + static struct ctl_table kern_table[] = { ++#ifndef CONFIG_SCHED_PDS + { + .procname = "sched_child_runs_first", + .data = &sysctl_sched_child_runs_first, +@@ -1854,6 +1859,7 @@ static struct ctl_table kern_table[] = { + .extra2 = SYSCTL_ONE, + }, + #endif ++#endif /* !CONFIG_SCHED_PDS */ + #ifdef CONFIG_PROVE_LOCKING + { + .procname = "prove_locking", +@@ -2430,6 +2436,26 @@ static struct ctl_table kern_table[] = { + .proc_handler = proc_dointvec, + }, + #endif ++#ifdef CONFIG_SCHED_PDS ++ { ++ .procname = "rr_interval", ++ .data = &rr_interval, ++ .maxlen = sizeof (int), ++ .mode = 0644, ++ .proc_handler = &proc_dointvec_minmax, ++ .extra1 = SYSCTL_ONE, ++ .extra2 = &one_thousand, ++ }, ++ { ++ .procname = "yield_type", ++ .data = &sched_yield_type, ++ .maxlen = sizeof (int), ++ .mode = 0644, ++ .proc_handler = &proc_dointvec_minmax, ++ .extra1 = SYSCTL_ZERO, ++ .extra2 = &two, ++ }, ++#endif + #if defined(CONFIG_S390) && defined(CONFIG_SMP) + { + .procname = "spin_retry", +diff --git a/kernel/time/posix-cpu-timers.c b/kernel/time/posix-cpu-timers.c +index a71758e34e45..fd62616c45ad 100644 +--- a/kernel/time/posix-cpu-timers.c ++++ b/kernel/time/posix-cpu-timers.c +@@ -216,7 +216,7 @@ static void task_sample_cputime(struct task_struct *p, u64 *samples) + u64 stime, utime; + + task_cputime(p, &utime, &stime); +- store_samples(samples, stime, utime, p->se.sum_exec_runtime); ++ store_samples(samples, stime, utime, tsk_seruntime(p)); + } + + static void proc_sample_cputime_atomic(struct task_cputime_atomic *at, +@@ -801,6 +801,7 @@ static void collect_posix_cputimers(struct posix_cputimers *pct, u64 *samples, + } + } + ++#ifndef CONFIG_SCHED_PDS + static inline void check_dl_overrun(struct task_struct *tsk) + { + if (tsk->dl.dl_overrun) { +@@ -808,6 +809,7 @@ static inline void check_dl_overrun(struct task_struct *tsk) + __group_send_sig_info(SIGXCPU, SEND_SIG_PRIV, tsk); + } + } ++#endif + + static bool check_rlimit(u64 time, u64 limit, int signo, bool rt, bool hard) + { +@@ -835,8 +837,10 @@ static void check_thread_timers(struct task_struct *tsk, + u64 samples[CPUCLOCK_MAX]; + unsigned long soft; + ++#ifndef CONFIG_SCHED_PDS + if (dl_task(tsk)) + check_dl_overrun(tsk); ++#endif + + if (expiry_cache_is_inactive(pct)) + return; +@@ -850,7 +854,7 @@ static void check_thread_timers(struct task_struct *tsk, + soft = task_rlimit(tsk, RLIMIT_RTTIME); + if (soft != RLIM_INFINITY) { + /* Task RT timeout is accounted in jiffies. RTTIME is usec */ +- unsigned long rttime = tsk->rt.timeout * (USEC_PER_SEC / HZ); ++ unsigned long rttime = tsk_rttimeout(tsk) * (USEC_PER_SEC / HZ); + unsigned long hard = task_rlimit_max(tsk, RLIMIT_RTTIME); + + /* At the hard limit, send SIGKILL. No further action. */ +@@ -1086,8 +1090,10 @@ static inline bool fastpath_timer_check(struct task_struct *tsk) + return true; + } + ++#ifndef CONFIG_SCHED_PDS + if (dl_task(tsk) && tsk->dl.dl_overrun) + return true; ++#endif + + return false; + } +diff --git a/kernel/trace/trace_selftest.c b/kernel/trace/trace_selftest.c +index b5e3496cf803..0816db0b9c16 100644 +--- a/kernel/trace/trace_selftest.c ++++ b/kernel/trace/trace_selftest.c +@@ -1048,10 +1048,15 @@ static int trace_wakeup_test_thread(void *data) + { + /* Make this a -deadline thread */ + static const struct sched_attr attr = { ++#ifdef CONFIG_SCHED_PDS ++ /* No deadline on BFS, use RR */ ++ .sched_policy = SCHED_RR, ++#else + .sched_policy = SCHED_DEADLINE, + .sched_runtime = 100000ULL, + .sched_deadline = 10000000ULL, + .sched_period = 10000000ULL ++#endif + }; + struct wakeup_test_data *x = data; +