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Commit d14c8a68 authored by Ingo Molnar's avatar Ingo Molnar
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Merge branch 'sched/for-linus' into tracing/for-linus

parents d59fdcf2 873a6ed6
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Showing with 1555 additions and 570 deletions
Documentation/scheduler/sched-domains.txt
View file @ d14c8a68
......@@ -61,10 +61,7 @@ builder by #define'ing ARCH_HASH_SCHED_DOMAIN, and exporting your
arch_init_sched_domains function. This function will attach domains to all
CPUs using cpu_attach_domain.
Implementors should change the line
#undef SCHED_DOMAIN_DEBUG
to
#define SCHED_DOMAIN_DEBUG
in kernel/sched.c as this enables an error checking parse of the sched domains
The sched-domains debugging infrastructure can be enabled by enabling
CONFIG_SCHED_DEBUG. This enables an error checking parse of the sched domains
which should catch most possible errors (described above). It also prints out
the domain structure in a visual format.
Documentation/scheduler/sched-rt-group.txt
View file @ d14c8a68
......@@ -51,9 +51,9 @@ needs only about 3% CPU time to do so, it can do with a 0.03 * 0.005s =
0.00015s. So this group can be scheduled with a period of 0.005s and a run time
of 0.00015s.
The remaining CPU time will be used for user input and other tass. Because
The remaining CPU time will be used for user input and other tasks. Because
realtime tasks have explicitly allocated the CPU time they need to perform
their tasks, buffer underruns in the graphocs or audio can be eliminated.
their tasks, buffer underruns in the graphics or audio can be eliminated.
NOTE: the above example is not fully implemented as of yet (2.6.25). We still
lack an EDF scheduler to make non-uniform periods usable.
......
include/linux/sched.h
View file @ d14c8a68
......@@ -134,7 +134,6 @@ extern unsigned long nr_running(void);
extern unsigned long nr_uninterruptible(void);
extern unsigned long nr_active(void);
extern unsigned long nr_iowait(void);
extern unsigned long weighted_cpuload(const int cpu);
struct seq_file;
struct cfs_rq;
......@@ -784,6 +783,8 @@ struct sched_domain {
unsigned int balance_interval; /* initialise to 1. units in ms. */
unsigned int nr_balance_failed; /* initialise to 0 */
u64 last_update;
#ifdef CONFIG_SCHEDSTATS
/* load_balance() stats */
unsigned int lb_count[CPU_MAX_IDLE_TYPES];
......@@ -823,23 +824,6 @@ extern int arch_reinit_sched_domains(void);
#endif /* CONFIG_SMP */
/*
* A runqueue laden with a single nice 0 task scores a weighted_cpuload of
* SCHED_LOAD_SCALE. This function returns 1 if any cpu is laden with a
* task of nice 0 or enough lower priority tasks to bring up the
* weighted_cpuload
*/
static inline int above_background_load(void)
{
unsigned long cpu;
for_each_online_cpu(cpu) {
if (weighted_cpuload(cpu) >= SCHED_LOAD_SCALE)
return 1;
}
return 0;
}
struct io_context; /* See blkdev.h */
#define NGROUPS_SMALL 32
#define NGROUPS_PER_BLOCK ((unsigned int)(PAGE_SIZE / sizeof(gid_t)))
......@@ -921,8 +905,8 @@ struct sched_class {
void (*set_cpus_allowed)(struct task_struct *p,
const cpumask_t *newmask);
void (*join_domain)(struct rq *rq);
void (*leave_domain)(struct rq *rq);
void (*rq_online)(struct rq *rq);
void (*rq_offline)(struct rq *rq);
void (*switched_from) (struct rq *this_rq, struct task_struct *task,
int running);
......@@ -1039,6 +1023,7 @@ struct task_struct {
#endif
int prio, static_prio, normal_prio;
unsigned int rt_priority;
const struct sched_class *sched_class;
struct sched_entity se;
struct sched_rt_entity rt;
......@@ -1122,7 +1107,6 @@ struct task_struct {
int __user *set_child_tid; /* CLONE_CHILD_SETTID */
int __user *clear_child_tid; /* CLONE_CHILD_CLEARTID */
unsigned int rt_priority;
cputime_t utime, stime, utimescaled, stimescaled;
cputime_t gtime;
cputime_t prev_utime, prev_stime;
......@@ -1141,12 +1125,12 @@ struct task_struct {
gid_t gid,egid,sgid,fsgid;
struct group_info *group_info;
kernel_cap_t cap_effective, cap_inheritable, cap_permitted, cap_bset;
unsigned securebits;
struct user_struct *user;
unsigned securebits;
#ifdef CONFIG_KEYS
unsigned char jit_keyring; /* default keyring to attach requested keys to */
struct key *request_key_auth; /* assumed request_key authority */
struct key *thread_keyring; /* keyring private to this thread */
unsigned char jit_keyring; /* default keyring to attach requested keys to */
#endif
char comm[TASK_COMM_LEN]; /* executable name excluding path
- access with [gs]et_task_comm (which lock
......@@ -1233,8 +1217,8 @@ struct task_struct {
# define MAX_LOCK_DEPTH 48UL
u64 curr_chain_key;
int lockdep_depth;
struct held_lock held_locks[MAX_LOCK_DEPTH];
unsigned int lockdep_recursion;
struct held_lock held_locks[MAX_LOCK_DEPTH];
#endif
/* journalling filesystem info */
......@@ -1262,10 +1246,6 @@ struct task_struct {
u64 acct_vm_mem1; /* accumulated virtual memory usage */
cputime_t acct_stimexpd;/* stime since last update */
#endif
#ifdef CONFIG_NUMA
struct mempolicy *mempolicy;
short il_next;
#endif
#ifdef CONFIG_CPUSETS
nodemask_t mems_allowed;
int cpuset_mems_generation;
......@@ -1284,6 +1264,10 @@ struct task_struct {
#endif
struct list_head pi_state_list;
struct futex_pi_state *pi_state_cache;
#endif
#ifdef CONFIG_NUMA
struct mempolicy *mempolicy;
short il_next;
#endif
atomic_t fs_excl; /* holding fs exclusive resources */
struct rcu_head rcu;
......@@ -1504,6 +1488,7 @@ static inline void put_task_struct(struct task_struct *t)
#define PF_SWAPWRITE 0x00800000 /* Allowed to write to swap */
#define PF_SPREAD_PAGE 0x01000000 /* Spread page cache over cpuset */
#define PF_SPREAD_SLAB 0x02000000 /* Spread some slab caches over cpuset */
#define PF_THREAD_BOUND 0x04000000 /* Thread bound to specific cpu */
#define PF_MEMPOLICY 0x10000000 /* Non-default NUMA mempolicy */
#define PF_MUTEX_TESTER 0x20000000 /* Thread belongs to the rt mutex tester */
#define PF_FREEZER_SKIP 0x40000000 /* Freezer should not count it as freezeable */
......@@ -1573,13 +1558,28 @@ static inline void sched_clock_idle_sleep_event(void)
static inline void sched_clock_idle_wakeup_event(u64 delta_ns)
{
}
#else
#ifdef CONFIG_NO_HZ
static inline void sched_clock_tick_stop(int cpu)
{
}
static inline void sched_clock_tick_start(int cpu)
{
}
#endif
#else /* CONFIG_HAVE_UNSTABLE_SCHED_CLOCK */
extern void sched_clock_init(void);
extern u64 sched_clock_cpu(int cpu);
extern void sched_clock_tick(void);
extern void sched_clock_idle_sleep_event(void);
extern void sched_clock_idle_wakeup_event(u64 delta_ns);
#ifdef CONFIG_NO_HZ
extern void sched_clock_tick_stop(int cpu);
extern void sched_clock_tick_start(int cpu);
#endif
#endif /* CONFIG_HAVE_UNSTABLE_SCHED_CLOCK */
/*
* For kernel-internal use: high-speed (but slightly incorrect) per-cpu
......@@ -1622,6 +1622,7 @@ extern unsigned int sysctl_sched_child_runs_first;
extern unsigned int sysctl_sched_features;
extern unsigned int sysctl_sched_migration_cost;
extern unsigned int sysctl_sched_nr_migrate;
extern unsigned int sysctl_sched_shares_ratelimit;
int sched_nr_latency_handler(struct ctl_table *table, int write,
struct file *file, void __user *buffer, size_t *length,
......
kernel/Makefile
View file @ d14c8a68
......@@ -3,7 +3,7 @@
#
obj-y = sched.o fork.o exec_domain.o panic.o printk.o profile.o \
exit.o itimer.o time.o softirq.o resource.o \
cpu.o exit.o itimer.o time.o softirq.o resource.o \
sysctl.o capability.o ptrace.o timer.o user.o \
signal.o sys.o kmod.o workqueue.o pid.o \
rcupdate.o extable.o params.o posix-timers.o \
......@@ -27,7 +27,7 @@ obj-$(CONFIG_RT_MUTEXES) += rtmutex.o
obj-$(CONFIG_DEBUG_RT_MUTEXES) += rtmutex-debug.o
obj-$(CONFIG_RT_MUTEX_TESTER) += rtmutex-tester.o
obj-$(CONFIG_GENERIC_ISA_DMA) += dma.o
obj-$(CONFIG_SMP) += cpu.o spinlock.o
obj-$(CONFIG_SMP) += spinlock.o
obj-$(CONFIG_DEBUG_SPINLOCK) += spinlock.o
obj-$(CONFIG_PROVE_LOCKING) += spinlock.o
obj-$(CONFIG_UID16) += uid16.o
......@@ -69,6 +69,7 @@ obj-$(CONFIG_TASK_DELAY_ACCT) += delayacct.o
obj-$(CONFIG_TASKSTATS) += taskstats.o tsacct.o
obj-$(CONFIG_MARKERS) += marker.o
obj-$(CONFIG_LATENCYTOP) += latencytop.o
obj-$(CONFIG_SMP) += sched_cpupri.o
ifneq ($(CONFIG_SCHED_NO_NO_OMIT_FRAME_POINTER),y)
# According to Alan Modra <alan@linuxcare.com.au>, the -fno-omit-frame-pointer is
......
kernel/cpu.c
View file @ d14c8a68
......@@ -15,6 +15,28 @@
#include <linux/stop_machine.h>
#include <linux/mutex.h>
/*
* Represents all cpu's present in the system
* In systems capable of hotplug, this map could dynamically grow
* as new cpu's are detected in the system via any platform specific
* method, such as ACPI for e.g.
*/
cpumask_t cpu_present_map __read_mostly;
EXPORT_SYMBOL(cpu_present_map);
#ifndef CONFIG_SMP
/*
* Represents all cpu's that are currently online.
*/
cpumask_t cpu_online_map __read_mostly = CPU_MASK_ALL;
EXPORT_SYMBOL(cpu_online_map);
cpumask_t cpu_possible_map __read_mostly = CPU_MASK_ALL;
EXPORT_SYMBOL(cpu_possible_map);
#else /* CONFIG_SMP */
/* Serializes the updates to cpu_online_map, cpu_present_map */
static DEFINE_MUTEX(cpu_add_remove_lock);
......@@ -403,3 +425,5 @@ void __ref enable_nonboot_cpus(void)
cpu_maps_update_done();
}
#endif /* CONFIG_PM_SLEEP_SMP */
#endif /* CONFIG_SMP */
kernel/cpuset.c
View file @ d14c8a68
......@@ -1194,6 +1194,15 @@ static int cpuset_can_attach(struct cgroup_subsys *ss,
if (cpus_empty(cs->cpus_allowed) || nodes_empty(cs->mems_allowed))
return -ENOSPC;
if (tsk->flags & PF_THREAD_BOUND) {
cpumask_t mask;
mutex_lock(&callback_mutex);
mask = cs->cpus_allowed;
mutex_unlock(&callback_mutex);
if (!cpus_equal(tsk->cpus_allowed, mask))
return -EINVAL;
}
return security_task_setscheduler(tsk, 0, NULL);
}
......@@ -1207,11 +1216,14 @@ static void cpuset_attach(struct cgroup_subsys *ss,
struct mm_struct *mm;
struct cpuset *cs = cgroup_cs(cont);
struct cpuset *oldcs = cgroup_cs(oldcont);
int err;
mutex_lock(&callback_mutex);
guarantee_online_cpus(cs, &cpus);
set_cpus_allowed_ptr(tsk, &cpus);
err = set_cpus_allowed_ptr(tsk, &cpus);
mutex_unlock(&callback_mutex);
if (err)
return;
from = oldcs->mems_allowed;
to = cs->mems_allowed;
......
kernel/kthread.c
View file @ d14c8a68
......@@ -180,6 +180,7 @@ void kthread_bind(struct task_struct *k, unsigned int cpu)
set_task_cpu(k, cpu);
k->cpus_allowed = cpumask_of_cpu(cpu);
k->rt.nr_cpus_allowed = 1;
k->flags |= PF_THREAD_BOUND;
}
EXPORT_SYMBOL(kthread_bind);
......
kernel/sched.c
View file @ d14c8a68
......@@ -74,6 +74,8 @@
#include <asm/tlb.h>
#include <asm/irq_regs.h>
#include "sched_cpupri.h"
/*
* Convert user-nice values [ -20 ... 0 ... 19 ]
* to static priority [ MAX_RT_PRIO..MAX_PRIO-1 ],
......@@ -289,15 +291,15 @@ struct task_group root_task_group;
static DEFINE_PER_CPU(struct sched_entity, init_sched_entity);
/* Default task group's cfs_rq on each cpu */
static DEFINE_PER_CPU(struct cfs_rq, init_cfs_rq) ____cacheline_aligned_in_smp;
#endif
#endif /* CONFIG_FAIR_GROUP_SCHED */
#ifdef CONFIG_RT_GROUP_SCHED
static DEFINE_PER_CPU(struct sched_rt_entity, init_sched_rt_entity);
static DEFINE_PER_CPU(struct rt_rq, init_rt_rq) ____cacheline_aligned_in_smp;
#endif
#else
#endif /* CONFIG_RT_GROUP_SCHED */
#else /* !CONFIG_FAIR_GROUP_SCHED */
#define root_task_group init_task_group
#endif
#endif /* CONFIG_FAIR_GROUP_SCHED */
/* task_group_lock serializes add/remove of task groups and also changes to
* a task group's cpu shares.
......@@ -307,9 +309,9 @@ static DEFINE_SPINLOCK(task_group_lock);
#ifdef CONFIG_FAIR_GROUP_SCHED
#ifdef CONFIG_USER_SCHED
# define INIT_TASK_GROUP_LOAD (2*NICE_0_LOAD)
#else
#else /* !CONFIG_USER_SCHED */
# define INIT_TASK_GROUP_LOAD NICE_0_LOAD
#endif
#endif /* CONFIG_USER_SCHED */
/*
* A weight of 0 or 1 can cause arithmetics problems.
......@@ -363,6 +365,10 @@ static inline void set_task_rq(struct task_struct *p, unsigned int cpu)
#else
static inline void set_task_rq(struct task_struct *p, unsigned int cpu) { }
static inline struct task_group *task_group(struct task_struct *p)
{
return NULL;
}
#endif /* CONFIG_GROUP_SCHED */
......@@ -373,6 +379,7 @@ struct cfs_rq {
u64 exec_clock;
u64 min_vruntime;
u64 pair_start;
struct rb_root tasks_timeline;
struct rb_node *rb_leftmost;
......@@ -401,6 +408,31 @@ struct cfs_rq {
*/
struct list_head leaf_cfs_rq_list;
struct task_group *tg; /* group that "owns" this runqueue */
#ifdef CONFIG_SMP
/*
* the part of load.weight contributed by tasks
*/
unsigned long task_weight;
/*
* h_load = weight * f(tg)
*
* Where f(tg) is the recursive weight fraction assigned to
* this group.
*/
unsigned long h_load;
/*
* this cpu's part of tg->shares
*/
unsigned long shares;
/*
* load.weight at the time we set shares
*/
unsigned long rq_weight;
#endif
#endif
};
......@@ -452,6 +484,9 @@ struct root_domain {
*/
cpumask_t rto_mask;
atomic_t rto_count;
#ifdef CONFIG_SMP
struct cpupri cpupri;
#endif
};
/*
......@@ -526,6 +561,9 @@ struct rq {
int push_cpu;
/* cpu of this runqueue: */
int cpu;
int online;
unsigned long avg_load_per_task;
struct task_struct *migration_thread;
struct list_head migration_queue;
......@@ -748,6 +786,12 @@ late_initcall(sched_init_debug);
*/
const_debug unsigned int sysctl_sched_nr_migrate = 32;
/*
* ratelimit for updating the group shares.
* default: 0.5ms
*/
const_debug unsigned int sysctl_sched_shares_ratelimit = 500000;
/*
* period over which we measure -rt task cpu usage in us.
* default: 1s
......@@ -775,82 +819,6 @@ static inline u64 global_rt_runtime(void)
return (u64)sysctl_sched_rt_runtime * NSEC_PER_USEC;
}
unsigned long long time_sync_thresh = 100000;
static DEFINE_PER_CPU(unsigned long long, time_offset);
static DEFINE_PER_CPU(unsigned long long, prev_cpu_time);
/*
* Global lock which we take every now and then to synchronize
* the CPUs time. This method is not warp-safe, but it's good
* enough to synchronize slowly diverging time sources and thus
* it's good enough for tracing:
*/
static DEFINE_SPINLOCK(time_sync_lock);
static unsigned long long prev_global_time;
static unsigned long long __sync_cpu_clock(unsigned long long time, int cpu)
{
/*
* We want this inlined, to not get tracer function calls
* in this critical section:
*/
spin_acquire(&time_sync_lock.dep_map, 0, 0, _THIS_IP_);
__raw_spin_lock(&time_sync_lock.raw_lock);
if (time < prev_global_time) {
per_cpu(time_offset, cpu) += prev_global_time - time;
time = prev_global_time;
} else {
prev_global_time = time;
}
__raw_spin_unlock(&time_sync_lock.raw_lock);
spin_release(&time_sync_lock.dep_map, 1, _THIS_IP_);
return time;
}
static unsigned long long __cpu_clock(int cpu)
{
unsigned long long now;
/*
* Only call sched_clock() if the scheduler has already been
* initialized (some code might call cpu_clock() very early):
*/
if (unlikely(!scheduler_running))
return 0;
now = sched_clock_cpu(cpu);
return now;
}
/*
* For kernel-internal use: high-speed (but slightly incorrect) per-cpu
* clock constructed from sched_clock():
*/
unsigned long long cpu_clock(int cpu)
{
unsigned long long prev_cpu_time, time, delta_time;
unsigned long flags;
local_irq_save(flags);
prev_cpu_time = per_cpu(prev_cpu_time, cpu);
time = __cpu_clock(cpu) + per_cpu(time_offset, cpu);
delta_time = time-prev_cpu_time;
if (unlikely(delta_time > time_sync_thresh)) {
time = __sync_cpu_clock(time, cpu);
per_cpu(prev_cpu_time, cpu) = time;
}
local_irq_restore(flags);
return time;
}
EXPORT_SYMBOL_GPL(cpu_clock);
#ifndef prepare_arch_switch
# define prepare_arch_switch(next) do { } while (0)
#endif
......@@ -1313,15 +1281,15 @@ void wake_up_idle_cpu(int cpu)
if (!tsk_is_polling(rq->idle))
smp_send_reschedule(cpu);
}
#endif
#endif /* CONFIG_NO_HZ */
#else
#else /* !CONFIG_SMP */
static void __resched_task(struct task_struct *p, int tif_bit)
{
assert_spin_locked(&task_rq(p)->lock);
set_tsk_thread_flag(p, tif_bit);
}
#endif
#endif /* CONFIG_SMP */
#if BITS_PER_LONG == 32
# define WMULT_CONST (~0UL)
......@@ -1336,6 +1304,9 @@ static void __resched_task(struct task_struct *p, int tif_bit)
*/
#define SRR(x, y) (((x) + (1UL << ((y) - 1))) >> (y))
/*
* delta *= weight / lw
*/
static unsigned long
calc_delta_mine(unsigned long delta_exec, unsigned long weight,
struct load_weight *lw)
......@@ -1363,12 +1334,6 @@ calc_delta_mine(unsigned long delta_exec, unsigned long weight,
return (unsigned long)min(tmp, (u64)(unsigned long)LONG_MAX);
}
static inline unsigned long
calc_delta_fair(unsigned long delta_exec, struct load_weight *lw)
{
return calc_delta_mine(delta_exec, NICE_0_LOAD, lw);
}
static inline void update_load_add(struct load_weight *lw, unsigned long inc)
{
lw->weight += inc;
......@@ -1479,17 +1444,211 @@ static inline void dec_cpu_load(struct rq *rq, unsigned long load)
#ifdef CONFIG_SMP
static unsigned long source_load(int cpu, int type);
static unsigned long target_load(int cpu, int type);
static unsigned long cpu_avg_load_per_task(int cpu);
static int task_hot(struct task_struct *p, u64 now, struct sched_domain *sd);
#else /* CONFIG_SMP */
static unsigned long cpu_avg_load_per_task(int cpu)
{
struct rq *rq = cpu_rq(cpu);
if (rq->nr_running)
rq->avg_load_per_task = rq->load.weight / rq->nr_running;
return rq->avg_load_per_task;
}
#ifdef CONFIG_FAIR_GROUP_SCHED
static void cfs_rq_set_shares(struct cfs_rq *cfs_rq, unsigned long shares)
typedef void (*tg_visitor)(struct task_group *, int, struct sched_domain *);
/*
* Iterate the full tree, calling @down when first entering a node and @up when
* leaving it for the final time.
*/
static void
walk_tg_tree(tg_visitor down, tg_visitor up, int cpu, struct sched_domain *sd)
{
struct task_group *parent, *child;
rcu_read_lock();
parent = &root_task_group;
down:
(*down)(parent, cpu, sd);
list_for_each_entry_rcu(child, &parent->children, siblings) {
parent = child;
goto down;
up:
continue;
}
(*up)(parent, cpu, sd);
child = parent;
parent = parent->parent;
if (parent)
goto up;
rcu_read_unlock();
}
static void __set_se_shares(struct sched_entity *se, unsigned long shares);
/*
* Calculate and set the cpu's group shares.
*/
static void
__update_group_shares_cpu(struct task_group *tg, int cpu,
unsigned long sd_shares, unsigned long sd_rq_weight)
{
int boost = 0;
unsigned long shares;
unsigned long rq_weight;
if (!tg->se[cpu])
return;
rq_weight = tg->cfs_rq[cpu]->load.weight;
/*
* If there are currently no tasks on the cpu pretend there is one of
* average load so that when a new task gets to run here it will not
* get delayed by group starvation.
*/
if (!rq_weight) {
boost = 1;
rq_weight = NICE_0_LOAD;
}
if (unlikely(rq_weight > sd_rq_weight))
rq_weight = sd_rq_weight;
/*
* \Sum shares * rq_weight
* shares = -----------------------
* \Sum rq_weight
*
*/
shares = (sd_shares * rq_weight) / (sd_rq_weight + 1);
/*
* record the actual number of shares, not the boosted amount.
*/
tg->cfs_rq[cpu]->shares = boost ? 0 : shares;
tg->cfs_rq[cpu]->rq_weight = rq_weight;
if (shares < MIN_SHARES)
shares = MIN_SHARES;
else if (shares > MAX_SHARES)
shares = MAX_SHARES;
__set_se_shares(tg->se[cpu], shares);
}
/*
* Re-compute the task group their per cpu shares over the given domain.
* This needs to be done in a bottom-up fashion because the rq weight of a
* parent group depends on the shares of its child groups.
*/
static void
tg_shares_up(struct task_group *tg, int cpu, struct sched_domain *sd)
{
unsigned long rq_weight = 0;
unsigned long shares = 0;
int i;
for_each_cpu_mask(i, sd->span) {
rq_weight += tg->cfs_rq[i]->load.weight;
shares += tg->cfs_rq[i]->shares;
}
if ((!shares && rq_weight) || shares > tg->shares)
shares = tg->shares;
if (!sd->parent || !(sd->parent->flags & SD_LOAD_BALANCE))
shares = tg->shares;
if (!rq_weight)
rq_weight = cpus_weight(sd->span) * NICE_0_LOAD;
for_each_cpu_mask(i, sd->span) {
struct rq *rq = cpu_rq(i);
unsigned long flags;
spin_lock_irqsave(&rq->lock, flags);
__update_group_shares_cpu(tg, i, shares, rq_weight);
spin_unlock_irqrestore(&rq->lock, flags);
}
}
/*
* Compute the cpu's hierarchical load factor for each task group.
* This needs to be done in a top-down fashion because the load of a child
* group is a fraction of its parents load.
*/
static void
tg_load_down(struct task_group *tg, int cpu, struct sched_domain *sd)
{
unsigned long load;
if (!tg->parent) {
load = cpu_rq(cpu)->load.weight;
} else {
load = tg->parent->cfs_rq[cpu]->h_load;
load *= tg->cfs_rq[cpu]->shares;
load /= tg->parent->cfs_rq[cpu]->load.weight + 1;
}
tg->cfs_rq[cpu]->h_load = load;
}
static void
tg_nop(struct task_group *tg, int cpu, struct sched_domain *sd)
{
}
static void update_shares(struct sched_domain *sd)
{
u64 now = cpu_clock(raw_smp_processor_id());
s64 elapsed = now - sd->last_update;
if (elapsed >= (s64)(u64)sysctl_sched_shares_ratelimit) {
sd->last_update = now;
walk_tg_tree(tg_nop, tg_shares_up, 0, sd);
}
}
static void update_shares_locked(struct rq *rq, struct sched_domain *sd)
{
spin_unlock(&rq->lock);
update_shares(sd);
spin_lock(&rq->lock);
}
static void update_h_load(int cpu)
{
walk_tg_tree(tg_load_down, tg_nop, cpu, NULL);
}
#else
static inline void update_shares(struct sched_domain *sd)
{
}
static inline void update_shares_locked(struct rq *rq, struct sched_domain *sd)
{
}
#endif
#endif /* CONFIG_SMP */
#endif
#ifdef CONFIG_FAIR_GROUP_SCHED
static void cfs_rq_set_shares(struct cfs_rq *cfs_rq, unsigned long shares)
{
#ifdef CONFIG_SMP
cfs_rq->shares = shares;
#endif
}
#endif
#include "sched_stats.h"
#include "sched_idletask.c"
......@@ -1500,27 +1659,17 @@ static void cfs_rq_set_shares(struct cfs_rq *cfs_rq, unsigned long shares)
#endif
#define sched_class_highest (&rt_sched_class)
#define for_each_class(class) \
for (class = sched_class_highest; class; class = class->next)
static inline void inc_load(struct rq *rq, const struct task_struct *p)
{
update_load_add(&rq->load, p->se.load.weight);
}
static inline void dec_load(struct rq *rq, const struct task_struct *p)
{
update_load_sub(&rq->load, p->se.load.weight);
}
static void inc_nr_running(struct task_struct *p, struct rq *rq)
static void inc_nr_running(struct rq *rq)
{
rq->nr_running++;
inc_load(rq, p);
}
static void dec_nr_running(struct task_struct *p, struct rq *rq)
static void dec_nr_running(struct rq *rq)
{
rq->nr_running--;
dec_load(rq, p);
}
static void set_load_weight(struct task_struct *p)
......@@ -1544,6 +1693,12 @@ static void set_load_weight(struct task_struct *p)
p->se.load.inv_weight = prio_to_wmult[p->static_prio - MAX_RT_PRIO];
}
static void update_avg(u64 *avg, u64 sample)
{
s64 diff = sample - *avg;
*avg += diff >> 3;
}
static void enqueue_task(struct rq *rq, struct task_struct *p, int wakeup)
{
sched_info_queued(p);
......@@ -1553,6 +1708,13 @@ static void enqueue_task(struct rq *rq, struct task_struct *p, int wakeup)
static void dequeue_task(struct rq *rq, struct task_struct *p, int sleep)
{
if (sleep && p->se.last_wakeup) {
update_avg(&p->se.avg_overlap,
p->se.sum_exec_runtime - p->se.last_wakeup);
p->se.last_wakeup = 0;
}
sched_info_dequeued(p);
p->sched_class->dequeue_task(rq, p, sleep);
p->se.on_rq = 0;
}
......@@ -1612,7 +1774,7 @@ static void activate_task(struct rq *rq, struct task_struct *p, int wakeup)
rq->nr_uninterruptible--;
enqueue_task(rq, p, wakeup);
inc_nr_running(p, rq);
inc_nr_running(rq);
}
/*
......@@ -1624,7 +1786,7 @@ static void deactivate_task(struct rq *rq, struct task_struct *p, int sleep)
rq->nr_uninterruptible++;
dequeue_task(rq, p, sleep);
dec_nr_running(p, rq);
dec_nr_running(rq);
}
/**
......@@ -1636,12 +1798,6 @@ inline int task_curr(const struct task_struct *p)
return cpu_curr(task_cpu(p)) == p;
}
/* Used instead of source_load when we know the type == 0 */
unsigned long weighted_cpuload(const int cpu)
{
return cpu_rq(cpu)->load.weight;
}
static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu)
{
set_task_rq(p, cpu);
......@@ -1670,6 +1826,12 @@ static inline void check_class_changed(struct rq *rq, struct task_struct *p,
#ifdef CONFIG_SMP
/* Used instead of source_load when we know the type == 0 */
static unsigned long weighted_cpuload(const int cpu)
{
return cpu_rq(cpu)->load.weight;
}
/*
* Is this task likely cache-hot:
*/
......@@ -1880,7 +2042,7 @@ static unsigned long source_load(int cpu, int type)
struct rq *rq = cpu_rq(cpu);
unsigned long total = weighted_cpuload(cpu);
if (type == 0)
if (type == 0 || !sched_feat(LB_BIAS))
return total;
return min(rq->cpu_load[type-1], total);
......@@ -1895,24 +2057,12 @@ static unsigned long target_load(int cpu, int type)
struct rq *rq = cpu_rq(cpu);
unsigned long total = weighted_cpuload(cpu);
if (type == 0)
if (type == 0 || !sched_feat(LB_BIAS))
return total;
return max(rq->cpu_load[type-1], total);
}
/*
* Return the average load per task on the cpu's run queue
*/
static unsigned long cpu_avg_load_per_task(int cpu)
{
struct rq *rq = cpu_rq(cpu);
unsigned long total = weighted_cpuload(cpu);
unsigned long n = rq->nr_running;
return n ? total / n : SCHED_LOAD_SCALE;
}
/*
* find_idlest_group finds and returns the least busy CPU group within the
* domain.
......@@ -2019,6 +2169,9 @@ static int sched_balance_self(int cpu, int flag)
sd = tmp;
}
if (sd)
update_shares(sd);
while (sd) {
cpumask_t span, tmpmask;
struct sched_group *group;
......@@ -2085,6 +2238,22 @@ static int try_to_wake_up(struct task_struct *p, unsigned int state, int sync)
if (!sched_feat(SYNC_WAKEUPS))
sync = 0;
#ifdef CONFIG_SMP
if (sched_feat(LB_WAKEUP_UPDATE)) {
struct sched_domain *sd;
this_cpu = raw_smp_processor_id();
cpu = task_cpu(p);
for_each_domain(this_cpu, sd) {
if (cpu_isset(cpu, sd->span)) {
update_shares(sd);
break;
}
}
}
#endif
smp_wmb();
rq = task_rq_lock(p, &flags);
old_state = p->state;
......@@ -2131,7 +2300,7 @@ static int try_to_wake_up(struct task_struct *p, unsigned int state, int sync)
}
}
}
#endif
#endif /* CONFIG_SCHEDSTATS */
out_activate:
#endif /* CONFIG_SMP */
......@@ -2157,6 +2326,8 @@ static int try_to_wake_up(struct task_struct *p, unsigned int state, int sync)
p->sched_class->task_wake_up(rq, p);
#endif
out:
current->se.last_wakeup = current->se.sum_exec_runtime;
task_rq_unlock(rq, &flags);
return success;
......@@ -2277,7 +2448,7 @@ void wake_up_new_task(struct task_struct *p, unsigned long clone_flags)
* management (if any):
*/
p->sched_class->task_new(rq, p);
inc_nr_running(p, rq);
inc_nr_running(rq);
}
check_preempt_curr(rq, p);
#ifdef CONFIG_SMP
......@@ -2331,7 +2502,7 @@ fire_sched_out_preempt_notifiers(struct task_struct *curr,
notifier->ops->sched_out(notifier, next);
}
#else
#else /* !CONFIG_PREEMPT_NOTIFIERS */
static void fire_sched_in_preempt_notifiers(struct task_struct *curr)
{
......@@ -2343,7 +2514,7 @@ fire_sched_out_preempt_notifiers(struct task_struct *curr,
{
}
#endif
#endif /* CONFIG_PREEMPT_NOTIFIERS */
/**
* prepare_task_switch - prepare to switch tasks
......@@ -2785,7 +2956,7 @@ balance_tasks(struct rq *this_rq, int this_cpu, struct rq *busiest,
enum cpu_idle_type idle, int *all_pinned,
int *this_best_prio, struct rq_iterator *iterator)
{
int loops = 0, pulled = 0, pinned = 0, skip_for_load;
int loops = 0, pulled = 0, pinned = 0;
struct task_struct *p;
long rem_load_move = max_load_move;
......@@ -2801,14 +2972,8 @@ balance_tasks(struct rq *this_rq, int this_cpu, struct rq *busiest,
next:
if (!p || loops++ > sysctl_sched_nr_migrate)
goto out;
/*
* To help distribute high priority tasks across CPUs we don't
* skip a task if it will be the highest priority task (i.e. smallest
* prio value) on its new queue regardless of its load weight
*/
skip_for_load = (p->se.load.weight >> 1) > rem_load_move +
SCHED_LOAD_SCALE_FUZZ;
if ((skip_for_load && p->prio >= *this_best_prio) ||
if ((p->se.load.weight >> 1) > rem_load_move ||
!can_migrate_task(p, busiest, this_cpu, sd, idle, &pinned)) {
p = iterator->next(iterator->arg);
goto next;
......@@ -2863,6 +3028,10 @@ static int move_tasks(struct rq *this_rq, int this_cpu, struct rq *busiest,
max_load_move - total_load_moved,
sd, idle, all_pinned, &this_best_prio);
class = class->next;
if (idle == CPU_NEWLY_IDLE && this_rq->nr_running)
break;
} while (class && max_load_move > total_load_moved);
return total_load_moved > 0;
......@@ -2939,6 +3108,7 @@ find_busiest_group(struct sched_domain *sd, int this_cpu,
max_load = this_load = total_load = total_pwr = 0;
busiest_load_per_task = busiest_nr_running = 0;
this_load_per_task = this_nr_running = 0;
if (idle == CPU_NOT_IDLE)
load_idx = sd->busy_idx;
else if (idle == CPU_NEWLY_IDLE)
......@@ -2953,6 +3123,8 @@ find_busiest_group(struct sched_domain *sd, int this_cpu,
int __group_imb = 0;
unsigned int balance_cpu = -1, first_idle_cpu = 0;
unsigned long sum_nr_running, sum_weighted_load;
unsigned long sum_avg_load_per_task;
unsigned long avg_load_per_task;
local_group = cpu_isset(this_cpu, group->cpumask);
......@@ -2961,6 +3133,8 @@ find_busiest_group(struct sched_domain *sd, int this_cpu,
/* Tally up the load of all CPUs in the group */
sum_weighted_load = sum_nr_running = avg_load = 0;
sum_avg_load_per_task = avg_load_per_task = 0;
max_cpu_load = 0;
min_cpu_load = ~0UL;
......@@ -2994,6 +3168,8 @@ find_busiest_group(struct sched_domain *sd, int this_cpu,
avg_load += load;
sum_nr_running += rq->nr_running;
sum_weighted_load += weighted_cpuload(i);
sum_avg_load_per_task += cpu_avg_load_per_task(i);
}
/*
......@@ -3015,7 +3191,20 @@ find_busiest_group(struct sched_domain *sd, int this_cpu,
avg_load = sg_div_cpu_power(group,
avg_load * SCHED_LOAD_SCALE);
if ((max_cpu_load - min_cpu_load) > SCHED_LOAD_SCALE)
/*
* Consider the group unbalanced when the imbalance is larger
* than the average weight of two tasks.
*
* APZ: with cgroup the avg task weight can vary wildly and
* might not be a suitable number - should we keep a
* normalized nr_running number somewhere that negates
* the hierarchy?
*/
avg_load_per_task = sg_div_cpu_power(group,
sum_avg_load_per_task * SCHED_LOAD_SCALE);
if ((max_cpu_load - min_cpu_load) > 2*avg_load_per_task)
__group_imb = 1;
group_capacity = group->__cpu_power / SCHED_LOAD_SCALE;
......@@ -3156,9 +3345,9 @@ find_busiest_group(struct sched_domain *sd, int this_cpu,
if (busiest_load_per_task > this_load_per_task)
imbn = 1;
} else
this_load_per_task = SCHED_LOAD_SCALE;
this_load_per_task = cpu_avg_load_per_task(this_cpu);
if (max_load - this_load + SCHED_LOAD_SCALE_FUZZ >=
if (max_load - this_load + 2*busiest_load_per_task >=
busiest_load_per_task * imbn) {
*imbalance = busiest_load_per_task;
return busiest;
......@@ -3284,6 +3473,7 @@ static int load_balance(int this_cpu, struct rq *this_rq,
schedstat_inc(sd, lb_count[idle]);
redo:
update_shares(sd);
group = find_busiest_group(sd, this_cpu, &imbalance, idle, &sd_idle,
cpus, balance);
......@@ -3386,8 +3576,9 @@ static int load_balance(int this_cpu, struct rq *this_rq,
if (!ld_moved && !sd_idle && sd->flags & SD_SHARE_CPUPOWER &&
!test_sd_parent(sd, SD_POWERSAVINGS_BALANCE))
return -1;
return ld_moved;
ld_moved = -1;
goto out;
out_balanced:
schedstat_inc(sd, lb_balanced[idle]);
......@@ -3402,8 +3593,13 @@ static int load_balance(int this_cpu, struct rq *this_rq,
if (!sd_idle && sd->flags & SD_SHARE_CPUPOWER &&
!test_sd_parent(sd, SD_POWERSAVINGS_BALANCE))
return -1;
return 0;
ld_moved = -1;
else
ld_moved = 0;
out:
if (ld_moved)
update_shares(sd);
return ld_moved;
}
/*
......@@ -3438,6 +3634,7 @@ load_balance_newidle(int this_cpu, struct rq *this_rq, struct sched_domain *sd,
schedstat_inc(sd, lb_count[CPU_NEWLY_IDLE]);
redo:
update_shares_locked(this_rq, sd);
group = find_busiest_group(sd, this_cpu, &imbalance, CPU_NEWLY_IDLE,
&sd_idle, cpus, NULL);
if (!group) {
......@@ -3481,6 +3678,7 @@ load_balance_newidle(int this_cpu, struct rq *this_rq, struct sched_domain *sd,
} else
sd->nr_balance_failed = 0;
update_shares_locked(this_rq, sd);
return ld_moved;
out_balanced:
......@@ -3672,6 +3870,7 @@ static void rebalance_domains(int cpu, enum cpu_idle_type idle)
/* Earliest time when we have to do rebalance again */
unsigned long next_balance = jiffies + 60*HZ;
int update_next_balance = 0;
int need_serialize;
cpumask_t tmp;
for_each_domain(cpu, sd) {
......@@ -3689,8 +3888,9 @@ static void rebalance_domains(int cpu, enum cpu_idle_type idle)
if (interval > HZ*NR_CPUS/10)
interval = HZ*NR_CPUS/10;
need_serialize = sd->flags & SD_SERIALIZE;
if (sd->flags & SD_SERIALIZE) {
if (need_serialize) {
if (!spin_trylock(&balancing))
goto out;
}
......@@ -3706,7 +3906,7 @@ static void rebalance_domains(int cpu, enum cpu_idle_type idle)
}
sd->last_balance = jiffies;
}
if (sd->flags & SD_SERIALIZE)
if (need_serialize)
spin_unlock(&balancing);
out:
if (time_after(next_balance, sd->last_balance + interval)) {
......@@ -4070,6 +4270,7 @@ static noinline void __schedule_bug(struct task_struct *prev)
prev->comm, prev->pid, preempt_count());
debug_show_held_locks(prev);
print_modules();
if (irqs_disabled())
print_irqtrace_events(prev);
......@@ -4143,7 +4344,7 @@ asmlinkage void __sched schedule(void)
struct task_struct *prev, *next;
unsigned long *switch_count;
struct rq *rq;
int cpu;
int cpu, hrtick = sched_feat(HRTICK);
need_resched:
preempt_disable();
......@@ -4158,6 +4359,7 @@ asmlinkage void __sched schedule(void)
schedule_debug(prev);
if (hrtick)
hrtick_clear(rq);
/*
......@@ -4204,6 +4406,7 @@ asmlinkage void __sched schedule(void)
} else
spin_unlock_irq(&rq->lock);
if (hrtick)
hrtick_set(rq);
if (unlikely(reacquire_kernel_lock(current) < 0))
......@@ -4586,10 +4789,8 @@ void set_user_nice(struct task_struct *p, long nice)
goto out_unlock;
}
on_rq = p->se.on_rq;
if (on_rq) {
if (on_rq)
dequeue_task(rq, p, 0);
dec_load(rq, p);
}
p->static_prio = NICE_TO_PRIO(nice);
set_load_weight(p);
......@@ -4599,7 +4800,6 @@ void set_user_nice(struct task_struct *p, long nice)
if (on_rq) {
enqueue_task(rq, p, 0);
inc_load(rq, p);
/*
* If the task increased its priority or is running and
* lowered its priority, then reschedule its CPU:
......@@ -5070,24 +5270,6 @@ asmlinkage long sys_sched_setaffinity(pid_t pid, unsigned int len,
return sched_setaffinity(pid, &new_mask);
}
/*
* Represents all cpu's present in the system
* In systems capable of hotplug, this map could dynamically grow
* as new cpu's are detected in the system via any platform specific
* method, such as ACPI for e.g.
*/
cpumask_t cpu_present_map __read_mostly;
EXPORT_SYMBOL(cpu_present_map);
#ifndef CONFIG_SMP
cpumask_t cpu_online_map __read_mostly = CPU_MASK_ALL;
EXPORT_SYMBOL(cpu_online_map);
cpumask_t cpu_possible_map __read_mostly = CPU_MASK_ALL;
EXPORT_SYMBOL(cpu_possible_map);
#endif
long sched_getaffinity(pid_t pid, cpumask_t *mask)
{
struct task_struct *p;
......@@ -5571,6 +5753,12 @@ int set_cpus_allowed_ptr(struct task_struct *p, const cpumask_t *new_mask)
goto out;
}
if (unlikely((p->flags & PF_THREAD_BOUND) && p != current &&
!cpus_equal(p->cpus_allowed, *new_mask))) {
ret = -EINVAL;
goto out;
}
if (p->sched_class->set_cpus_allowed)
p->sched_class->set_cpus_allowed(p, new_mask);
else {
......@@ -6060,6 +6248,36 @@ static void unregister_sched_domain_sysctl(void)
}
#endif
static void set_rq_online(struct rq *rq)
{
if (!rq->online) {
const struct sched_class *class;
cpu_set(rq->cpu, rq->rd->online);
rq->online = 1;
for_each_class(class) {
if (class->rq_online)
class->rq_online(rq);
}
}
}
static void set_rq_offline(struct rq *rq)
{
if (rq->online) {
const struct sched_class *class;
for_each_class(class) {
if (class->rq_offline)
class->rq_offline(rq);
}
cpu_clear(rq->cpu, rq->rd->online);
rq->online = 0;
}
}
/*
* migration_call - callback that gets triggered when a CPU is added.
* Here we can start up the necessary migration thread for the new CPU.
......@@ -6097,7 +6315,8 @@ migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu)
spin_lock_irqsave(&rq->lock, flags);
if (rq->rd) {
BUG_ON(!cpu_isset(cpu, rq->rd->span));
cpu_set(cpu, rq->rd->online);
set_rq_online(rq);
}
spin_unlock_irqrestore(&rq->lock, flags);
break;
......@@ -6158,7 +6377,7 @@ migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu)
spin_lock_irqsave(&rq->lock, flags);
if (rq->rd) {
BUG_ON(!cpu_isset(cpu, rq->rd->span));
cpu_clear(cpu, rq->rd->online);
set_rq_offline(rq);
}
spin_unlock_irqrestore(&rq->lock, flags);
break;
......@@ -6192,6 +6411,28 @@ void __init migration_init(void)
#ifdef CONFIG_SCHED_DEBUG
static inline const char *sd_level_to_string(enum sched_domain_level lvl)
{
switch (lvl) {
case SD_LV_NONE:
return "NONE";
case SD_LV_SIBLING:
return "SIBLING";
case SD_LV_MC:
return "MC";
case SD_LV_CPU:
return "CPU";
case SD_LV_NODE:
return "NODE";
case SD_LV_ALLNODES:
return "ALLNODES";
case SD_LV_MAX:
return "MAX";
}
return "MAX";
}
static int sched_domain_debug_one(struct sched_domain *sd, int cpu, int level,
cpumask_t *groupmask)
{
......@@ -6211,7 +6452,8 @@ static int sched_domain_debug_one(struct sched_domain *sd, int cpu, int level,
return -1;
}
printk(KERN_CONT "span %s\n", str);
printk(KERN_CONT "span %s level %s\n",
str, sd_level_to_string(sd->level));
if (!cpu_isset(cpu, sd->span)) {
printk(KERN_ERR "ERROR: domain->span does not contain "
......@@ -6295,9 +6537,9 @@ static void sched_domain_debug(struct sched_domain *sd, int cpu)
}
kfree(groupmask);
}
#else
#else /* !CONFIG_SCHED_DEBUG */
# define sched_domain_debug(sd, cpu) do { } while (0)
#endif
#endif /* CONFIG_SCHED_DEBUG */
static int sd_degenerate(struct sched_domain *sd)
{
......@@ -6357,20 +6599,16 @@ sd_parent_degenerate(struct sched_domain *sd, struct sched_domain *parent)
static void rq_attach_root(struct rq *rq, struct root_domain *rd)
{
unsigned long flags;
const struct sched_class *class;
spin_lock_irqsave(&rq->lock, flags);
if (rq->rd) {
struct root_domain *old_rd = rq->rd;
for (class = sched_class_highest; class; class = class->next) {
if (class->leave_domain)
class->leave_domain(rq);
}
if (cpu_isset(rq->cpu, old_rd->online))
set_rq_offline(rq);
cpu_clear(rq->cpu, old_rd->span);
cpu_clear(rq->cpu, old_rd->online);
if (atomic_dec_and_test(&old_rd->refcount))
kfree(old_rd);
......@@ -6381,12 +6619,7 @@ static void rq_attach_root(struct rq *rq, struct root_domain *rd)
cpu_set(rq->cpu, rd->span);
if (cpu_isset(rq->cpu, cpu_online_map))
cpu_set(rq->cpu, rd->online);
for (class = sched_class_highest; class; class = class->next) {
if (class->join_domain)
class->join_domain(rq);
}
set_rq_online(rq);
spin_unlock_irqrestore(&rq->lock, flags);
}
......@@ -6397,6 +6630,8 @@ static void init_rootdomain(struct root_domain *rd)
cpus_clear(rd->span);
cpus_clear(rd->online);
cpupri_init(&rd->cpupri);
}
static void init_defrootdomain(void)
......@@ -6591,7 +6826,7 @@ static void sched_domain_node_span(int node, cpumask_t *span)
cpus_or(*span, *span, *nodemask);
}
}
#endif
#endif /* CONFIG_NUMA */
int sched_smt_power_savings = 0, sched_mc_power_savings = 0;
......@@ -6610,7 +6845,7 @@ cpu_to_cpu_group(int cpu, const cpumask_t *cpu_map, struct sched_group **sg,
*sg = &per_cpu(sched_group_cpus, cpu);
return cpu;
}
#endif
#endif /* CONFIG_SCHED_SMT */
/*
* multi-core sched-domains:
......@@ -6618,7 +6853,7 @@ cpu_to_cpu_group(int cpu, const cpumask_t *cpu_map, struct sched_group **sg,
#ifdef CONFIG_SCHED_MC
static DEFINE_PER_CPU(struct sched_domain, core_domains);
static DEFINE_PER_CPU(struct sched_group, sched_group_core);
#endif
#endif /* CONFIG_SCHED_MC */
#if defined(CONFIG_SCHED_MC) && defined(CONFIG_SCHED_SMT)
static int
......@@ -6720,7 +6955,7 @@ static void init_numa_sched_groups_power(struct sched_group *group_head)
sg = sg->next;
} while (sg != group_head);
}
#endif
#endif /* CONFIG_NUMA */
#ifdef CONFIG_NUMA
/* Free memory allocated for various sched_group structures */
......@@ -6757,11 +6992,11 @@ static void free_sched_groups(const cpumask_t *cpu_map, cpumask_t *nodemask)
sched_group_nodes_bycpu[cpu] = NULL;
}
}
#else
#else /* !CONFIG_NUMA */
static void free_sched_groups(const cpumask_t *cpu_map, cpumask_t *nodemask)
{
}
#endif
#endif /* CONFIG_NUMA */
/*
* Initialize sched groups cpu_power.
......@@ -7470,7 +7705,7 @@ int sched_create_sysfs_power_savings_entries(struct sysdev_class *cls)
#endif
return err;
}
#endif
#endif /* CONFIG_SCHED_MC || CONFIG_SCHED_SMT */
/*
* Force a reinitialization of the sched domains hierarchy. The domains
......@@ -7481,21 +7716,28 @@ int sched_create_sysfs_power_savings_entries(struct sysdev_class *cls)
static int update_sched_domains(struct notifier_block *nfb,
unsigned long action, void *hcpu)
{
int cpu = (int)(long)hcpu;
switch (action) {
case CPU_UP_PREPARE:
case CPU_UP_PREPARE_FROZEN:
case CPU_DOWN_PREPARE:
case CPU_DOWN_PREPARE_FROZEN:
disable_runtime(cpu_rq(cpu));
/* fall-through */
case CPU_UP_PREPARE:
case CPU_UP_PREPARE_FROZEN:
detach_destroy_domains(&cpu_online_map);
free_sched_domains();
return NOTIFY_OK;
case CPU_UP_CANCELED:
case CPU_UP_CANCELED_FROZEN:
case CPU_DOWN_FAILED:
case CPU_DOWN_FAILED_FROZEN:
case CPU_ONLINE:
case CPU_ONLINE_FROZEN:
enable_runtime(cpu_rq(cpu));
/* fall-through */
case CPU_UP_CANCELED:
case CPU_UP_CANCELED_FROZEN:
case CPU_DEAD:
case CPU_DEAD_FROZEN:
/*
......@@ -7695,8 +7937,8 @@ void __init sched_init(void)
root_task_group.cfs_rq = (struct cfs_rq **)ptr;
ptr += nr_cpu_ids * sizeof(void **);
#endif
#endif
#endif /* CONFIG_USER_SCHED */
#endif /* CONFIG_FAIR_GROUP_SCHED */
#ifdef CONFIG_RT_GROUP_SCHED
init_task_group.rt_se = (struct sched_rt_entity **)ptr;
ptr += nr_cpu_ids * sizeof(void **);
......@@ -7710,8 +7952,8 @@ void __init sched_init(void)
root_task_group.rt_rq = (struct rt_rq **)ptr;
ptr += nr_cpu_ids * sizeof(void **);
#endif
#endif
#endif /* CONFIG_USER_SCHED */
#endif /* CONFIG_RT_GROUP_SCHED */
}
#ifdef CONFIG_SMP
......@@ -7727,8 +7969,8 @@ void __init sched_init(void)
#ifdef CONFIG_USER_SCHED
init_rt_bandwidth(&root_task_group.rt_bandwidth,
global_rt_period(), RUNTIME_INF);
#endif
#endif
#endif /* CONFIG_USER_SCHED */
#endif /* CONFIG_RT_GROUP_SCHED */
#ifdef CONFIG_GROUP_SCHED
list_add(&init_task_group.list, &task_groups);
......@@ -7738,8 +7980,8 @@ void __init sched_init(void)
INIT_LIST_HEAD(&root_task_group.children);
init_task_group.parent = &root_task_group;
list_add(&init_task_group.siblings, &root_task_group.children);
#endif
#endif
#endif /* CONFIG_USER_SCHED */
#endif /* CONFIG_GROUP_SCHED */
for_each_possible_cpu(i) {
struct rq *rq;
......@@ -7819,6 +8061,7 @@ void __init sched_init(void)
rq->next_balance = jiffies;
rq->push_cpu = 0;
rq->cpu = i;
rq->online = 0;
rq->migration_thread = NULL;
INIT_LIST_HEAD(&rq->migration_queue);
rq_attach_root(rq, &def_root_domain);
......@@ -8058,7 +8301,7 @@ static inline void unregister_fair_sched_group(struct task_group *tg, int cpu)
{
list_del_rcu(&tg->cfs_rq[cpu]->leaf_cfs_rq_list);
}
#else
#else /* !CONFG_FAIR_GROUP_SCHED */
static inline void free_fair_sched_group(struct task_group *tg)
{
}
......@@ -8076,7 +8319,7 @@ static inline void register_fair_sched_group(struct task_group *tg, int cpu)
static inline void unregister_fair_sched_group(struct task_group *tg, int cpu)
{
}
#endif
#endif /* CONFIG_FAIR_GROUP_SCHED */
#ifdef CONFIG_RT_GROUP_SCHED
static void free_rt_sched_group(struct task_group *tg)
......@@ -8147,7 +8390,7 @@ static inline void unregister_rt_sched_group(struct task_group *tg, int cpu)
{
list_del_rcu(&tg->rt_rq[cpu]->leaf_rt_rq_list);
}
#else
#else /* !CONFIG_RT_GROUP_SCHED */
static inline void free_rt_sched_group(struct task_group *tg)
{
}
......@@ -8165,7 +8408,7 @@ static inline void register_rt_sched_group(struct task_group *tg, int cpu)
static inline void unregister_rt_sched_group(struct task_group *tg, int cpu)
{
}
#endif
#endif /* CONFIG_RT_GROUP_SCHED */
#ifdef CONFIG_GROUP_SCHED
static void free_sched_group(struct task_group *tg)
......@@ -8276,17 +8519,14 @@ void sched_move_task(struct task_struct *tsk)
task_rq_unlock(rq, &flags);
}
#endif
#endif /* CONFIG_GROUP_SCHED */
#ifdef CONFIG_FAIR_GROUP_SCHED
static void set_se_shares(struct sched_entity *se, unsigned long shares)
static void __set_se_shares(struct sched_entity *se, unsigned long shares)
{
struct cfs_rq *cfs_rq = se->cfs_rq;
struct rq *rq = cfs_rq->rq;
int on_rq;
spin_lock_irq(&rq->lock);
on_rq = se->on_rq;
if (on_rq)
dequeue_entity(cfs_rq, se, 0);
......@@ -8296,8 +8536,17 @@ static void set_se_shares(struct sched_entity *se, unsigned long shares)
if (on_rq)
enqueue_entity(cfs_rq, se, 0);
}
spin_unlock_irq(&rq->lock);
static void set_se_shares(struct sched_entity *se, unsigned long shares)
{
struct cfs_rq *cfs_rq = se->cfs_rq;
struct rq *rq = cfs_rq->rq;
unsigned long flags;
spin_lock_irqsave(&rq->lock, flags);
__set_se_shares(se, shares);
spin_unlock_irqrestore(&rq->lock, flags);
}
static DEFINE_MUTEX(shares_mutex);
......@@ -8336,8 +8585,13 @@ int sched_group_set_shares(struct task_group *tg, unsigned long shares)
* w/o tripping rebalance_share or load_balance_fair.
*/
tg->shares = shares;
for_each_possible_cpu(i)
for_each_possible_cpu(i) {
/*
* force a rebalance
*/
cfs_rq_set_shares(tg->cfs_rq[i], 0);
set_se_shares(tg->se[i], shares);
}
/*
* Enable load balance activity on this group, by inserting it back on
......@@ -8376,7 +8630,7 @@ static unsigned long to_ratio(u64 period, u64 runtime)
#ifdef CONFIG_CGROUP_SCHED
static int __rt_schedulable(struct task_group *tg, u64 period, u64 runtime)
{
struct task_group *tgi, *parent = tg ? tg->parent : NULL;
struct task_group *tgi, *parent = tg->parent;
unsigned long total = 0;
if (!parent) {
......@@ -8400,7 +8654,7 @@ static int __rt_schedulable(struct task_group *tg, u64 period, u64 runtime)
}
rcu_read_unlock();
return total + to_ratio(period, runtime) <
return total + to_ratio(period, runtime) <=
to_ratio(ktime_to_ns(parent->rt_bandwidth.rt_period),
parent->rt_bandwidth.rt_runtime);
}
......@@ -8520,16 +8774,21 @@ long sched_group_rt_period(struct task_group *tg)
static int sched_rt_global_constraints(void)
{
struct task_group *tg = &root_task_group;
u64 rt_runtime, rt_period;
int ret = 0;
rt_period = ktime_to_ns(tg->rt_bandwidth.rt_period);
rt_runtime = tg->rt_bandwidth.rt_runtime;
mutex_lock(&rt_constraints_mutex);
if (!__rt_schedulable(NULL, 1, 0))
if (!__rt_schedulable(tg, rt_period, rt_runtime))
ret = -EINVAL;
mutex_unlock(&rt_constraints_mutex);
return ret;
}
#else
#else /* !CONFIG_RT_GROUP_SCHED */
static int sched_rt_global_constraints(void)
{
unsigned long flags;
......@@ -8547,7 +8806,7 @@ static int sched_rt_global_constraints(void)
return 0;
}
#endif
#endif /* CONFIG_RT_GROUP_SCHED */
int sched_rt_handler(struct ctl_table *table, int write,
struct file *filp, void __user *buffer, size_t *lenp,
......@@ -8655,7 +8914,7 @@ static u64 cpu_shares_read_u64(struct cgroup *cgrp, struct cftype *cft)
return (u64) tg->shares;
}
#endif
#endif /* CONFIG_FAIR_GROUP_SCHED */
#ifdef CONFIG_RT_GROUP_SCHED
static int cpu_rt_runtime_write(struct cgroup *cgrp, struct cftype *cft,
......@@ -8679,7 +8938,7 @@ static u64 cpu_rt_period_read_uint(struct cgroup *cgrp, struct cftype *cft)
{
return sched_group_rt_period(cgroup_tg(cgrp));
}
#endif
#endif /* CONFIG_RT_GROUP_SCHED */
static struct cftype cpu_files[] = {
#ifdef CONFIG_FAIR_GROUP_SCHED
......
kernel/sched_clock.c
View file @ d14c8a68
......@@ -3,6 +3,9 @@
*
* Copyright (C) 2008 Red Hat, Inc., Peter Zijlstra <pzijlstr@redhat.com>
*
* Updates and enhancements:
* Copyright (C) 2008 Red Hat, Inc. Steven Rostedt <srostedt@redhat.com>
*
* Based on code by:
* Ingo Molnar <mingo@redhat.com>
* Guillaume Chazarain <guichaz@gmail.com>
......@@ -32,6 +35,11 @@
#ifdef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
#define MULTI_SHIFT 15
/* Max is double, Min is 1/2 */
#define MAX_MULTI (2LL << MULTI_SHIFT)
#define MIN_MULTI (1LL << (MULTI_SHIFT-1))
struct sched_clock_data {
/*
* Raw spinlock - this is a special case: this might be called
......@@ -40,11 +48,15 @@ struct sched_clock_data {
*/
raw_spinlock_t lock;
unsigned long prev_jiffies;
unsigned long tick_jiffies;
u64 prev_raw;
u64 tick_raw;
u64 tick_gtod;
u64 clock;
s64 multi;
#ifdef CONFIG_NO_HZ
int check_max;
#endif
};
static DEFINE_PER_CPU_SHARED_ALIGNED(struct sched_clock_data, sched_clock_data);
......@@ -71,41 +83,91 @@ void sched_clock_init(void)
struct sched_clock_data *scd = cpu_sdc(cpu);
scd->lock = (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED;
scd->prev_jiffies = now_jiffies;
scd->tick_jiffies = now_jiffies;
scd->prev_raw = 0;
scd->tick_raw = 0;
scd->tick_gtod = ktime_now;
scd->clock = ktime_now;
scd->multi = 1 << MULTI_SHIFT;
#ifdef CONFIG_NO_HZ
scd->check_max = 1;
#endif
}
sched_clock_running = 1;
}
#ifdef CONFIG_NO_HZ
/*
* The dynamic ticks makes the delta jiffies inaccurate. This
* prevents us from checking the maximum time update.
* Disable the maximum check during stopped ticks.
*/
void sched_clock_tick_stop(int cpu)
{
struct sched_clock_data *scd = cpu_sdc(cpu);
scd->check_max = 0;
}
void sched_clock_tick_start(int cpu)
{
struct sched_clock_data *scd = cpu_sdc(cpu);
scd->check_max = 1;
}
static int check_max(struct sched_clock_data *scd)
{
return scd->check_max;
}
#else
static int check_max(struct sched_clock_data *scd)
{
return 1;
}
#endif /* CONFIG_NO_HZ */
/*
* update the percpu scd from the raw @now value
*
* - filter out backward motion
* - use jiffies to generate a min,max window to clip the raw values
*/
static void __update_sched_clock(struct sched_clock_data *scd, u64 now)
static void __update_sched_clock(struct sched_clock_data *scd, u64 now, u64 *time)
{
unsigned long now_jiffies = jiffies;
long delta_jiffies = now_jiffies - scd->prev_jiffies;
long delta_jiffies = now_jiffies - scd->tick_jiffies;
u64 clock = scd->clock;
u64 min_clock, max_clock;
s64 delta = now - scd->prev_raw;
WARN_ON_ONCE(!irqs_disabled());
min_clock = scd->tick_gtod + delta_jiffies * TICK_NSEC;
/*
* At schedule tick the clock can be just under the gtod. We don't
* want to push it too prematurely.
*/
min_clock = scd->tick_gtod + (delta_jiffies * TICK_NSEC);
if (min_clock > TICK_NSEC)
min_clock -= TICK_NSEC / 2;
if (unlikely(delta < 0)) {
clock++;
goto out;
}
max_clock = min_clock + TICK_NSEC;
/*
* The clock must stay within a jiffie of the gtod.
* But since we may be at the start of a jiffy or the end of one
* we add another jiffy buffer.
*/
max_clock = scd->tick_gtod + (2 + delta_jiffies) * TICK_NSEC;
delta *= scd->multi;
delta >>= MULTI_SHIFT;
if (unlikely(clock + delta > max_clock)) {
if (unlikely(clock + delta > max_clock) && check_max(scd)) {
if (clock < max_clock)
clock = max_clock;
else
......@@ -118,9 +180,12 @@ static void __update_sched_clock(struct sched_clock_data *scd, u64 now)
if (unlikely(clock < min_clock))
clock = min_clock;
if (time)
*time = clock;
else {
scd->prev_raw = now;
scd->prev_jiffies = now_jiffies;
scd->clock = clock;
}
}
static void lock_double_clock(struct sched_clock_data *data1,
......@@ -160,18 +225,21 @@ u64 sched_clock_cpu(int cpu)
now -= my_scd->tick_raw;
now += scd->tick_raw;
now -= my_scd->tick_gtod;
now += scd->tick_gtod;
now += my_scd->tick_gtod;
now -= scd->tick_gtod;
__raw_spin_unlock(&my_scd->lock);
__update_sched_clock(scd, now, &clock);
__raw_spin_unlock(&scd->lock);
} else {
__raw_spin_lock(&scd->lock);
}
__update_sched_clock(scd, now);
__update_sched_clock(scd, now, NULL);
clock = scd->clock;
__raw_spin_unlock(&scd->lock);
}
return clock;
}
......@@ -179,6 +247,8 @@ u64 sched_clock_cpu(int cpu)
void sched_clock_tick(void)
{
struct sched_clock_data *scd = this_scd();
unsigned long now_jiffies = jiffies;
s64 mult, delta_gtod, delta_raw;
u64 now, now_gtod;
if (unlikely(!sched_clock_running))
......@@ -186,18 +256,33 @@ void sched_clock_tick(void)
WARN_ON_ONCE(!irqs_disabled());
now = sched_clock();
now_gtod = ktime_to_ns(ktime_get());
now = sched_clock();
__raw_spin_lock(&scd->lock);
__update_sched_clock(scd, now);
__update_sched_clock(scd, now, NULL);
/*
* update tick_gtod after __update_sched_clock() because that will
* already observe 1 new jiffy; adding a new tick_gtod to that would
* increase the clock 2 jiffies.
*/
delta_gtod = now_gtod - scd->tick_gtod;
delta_raw = now - scd->tick_raw;
if ((long)delta_raw > 0) {
mult = delta_gtod << MULTI_SHIFT;
do_div(mult, delta_raw);
scd->multi = mult;
if (scd->multi > MAX_MULTI)
scd->multi = MAX_MULTI;
else if (scd->multi < MIN_MULTI)
scd->multi = MIN_MULTI;
} else
scd->multi = 1 << MULTI_SHIFT;
scd->tick_raw = now;
scd->tick_gtod = now_gtod;
scd->tick_jiffies = now_jiffies;
__raw_spin_unlock(&scd->lock);
}
......@@ -227,6 +312,7 @@ void sched_clock_idle_wakeup_event(u64 delta_ns)
__raw_spin_lock(&scd->lock);
scd->prev_raw = now;
scd->clock += delta_ns;
scd->multi = 1 << MULTI_SHIFT;
__raw_spin_unlock(&scd->lock);
touch_softlockup_watchdog();
......@@ -244,3 +330,16 @@ unsigned long long __attribute__((weak)) sched_clock(void)
{
return (unsigned long long)jiffies * (NSEC_PER_SEC / HZ);
}
unsigned long long cpu_clock(int cpu)
{
unsigned long long clock;
unsigned long flags;
local_irq_save(flags);
clock = sched_clock_cpu(cpu);
local_irq_restore(flags);
return clock;
}
EXPORT_SYMBOL_GPL(cpu_clock);
kernel/sched_cpupri.c 0 → 100644
View file @ d14c8a68
/*
* kernel/sched_cpupri.c
*
* CPU priority management
*
* Copyright (C) 2007-2008 Novell
*
* Author: Gregory Haskins <ghaskins@novell.com>
*
* This code tracks the priority of each CPU so that global migration
* decisions are easy to calculate. Each CPU can be in a state as follows:
*
* (INVALID), IDLE, NORMAL, RT1, ... RT99
*
* going from the lowest priority to the highest. CPUs in the INVALID state
* are not eligible for routing. The system maintains this state with
* a 2 dimensional bitmap (the first for priority class, the second for cpus
* in that class). Therefore a typical application without affinity
* restrictions can find a suitable CPU with O(1) complexity (e.g. two bit
* searches). For tasks with affinity restrictions, the algorithm has a
* worst case complexity of O(min(102, nr_domcpus)), though the scenario that
* yields the worst case search is fairly contrived.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; version 2
* of the License.
*/
#include "sched_cpupri.h"
/* Convert between a 140 based task->prio, and our 102 based cpupri */
static int convert_prio(int prio)
{
int cpupri;
if (prio == CPUPRI_INVALID)
cpupri = CPUPRI_INVALID;
else if (prio == MAX_PRIO)
cpupri = CPUPRI_IDLE;
else if (prio >= MAX_RT_PRIO)
cpupri = CPUPRI_NORMAL;
else
cpupri = MAX_RT_PRIO - prio + 1;
return cpupri;
}
#define for_each_cpupri_active(array, idx) \
for (idx = find_first_bit(array, CPUPRI_NR_PRIORITIES); \
idx < CPUPRI_NR_PRIORITIES; \
idx = find_next_bit(array, CPUPRI_NR_PRIORITIES, idx+1))
/**
* cpupri_find - find the best (lowest-pri) CPU in the system
* @cp: The cpupri context
* @p: The task
* @lowest_mask: A mask to fill in with selected CPUs
*
* Note: This function returns the recommended CPUs as calculated during the
* current invokation. By the time the call returns, the CPUs may have in
* fact changed priorities any number of times. While not ideal, it is not
* an issue of correctness since the normal rebalancer logic will correct
* any discrepancies created by racing against the uncertainty of the current
* priority configuration.
*
* Returns: (int)bool - CPUs were found
*/
int cpupri_find(struct cpupri *cp, struct task_struct *p,
cpumask_t *lowest_mask)
{
int idx = 0;
int task_pri = convert_prio(p->prio);
for_each_cpupri_active(cp->pri_active, idx) {
struct cpupri_vec *vec = &cp->pri_to_cpu[idx];
cpumask_t mask;
if (idx >= task_pri)
break;
cpus_and(mask, p->cpus_allowed, vec->mask);
if (cpus_empty(mask))
continue;
*lowest_mask = mask;
return 1;
}
return 0;
}
/**
* cpupri_set - update the cpu priority setting
* @cp: The cpupri context
* @cpu: The target cpu
* @pri: The priority (INVALID-RT99) to assign to this CPU
*
* Note: Assumes cpu_rq(cpu)->lock is locked
*
* Returns: (void)
*/
void cpupri_set(struct cpupri *cp, int cpu, int newpri)
{
int *currpri = &cp->cpu_to_pri[cpu];
int oldpri = *currpri;
unsigned long flags;
newpri = convert_prio(newpri);
BUG_ON(newpri >= CPUPRI_NR_PRIORITIES);
if (newpri == oldpri)
return;
/*
* If the cpu was currently mapped to a different value, we
* first need to unmap the old value
*/
if (likely(oldpri != CPUPRI_INVALID)) {
struct cpupri_vec *vec = &cp->pri_to_cpu[oldpri];
spin_lock_irqsave(&vec->lock, flags);
vec->count--;
if (!vec->count)
clear_bit(oldpri, cp->pri_active);
cpu_clear(cpu, vec->mask);
spin_unlock_irqrestore(&vec->lock, flags);
}
if (likely(newpri != CPUPRI_INVALID)) {
struct cpupri_vec *vec = &cp->pri_to_cpu[newpri];
spin_lock_irqsave(&vec->lock, flags);
cpu_set(cpu, vec->mask);
vec->count++;
if (vec->count == 1)
set_bit(newpri, cp->pri_active);
spin_unlock_irqrestore(&vec->lock, flags);
}
*currpri = newpri;
}
/**
* cpupri_init - initialize the cpupri structure
* @cp: The cpupri context
*
* Returns: (void)
*/
void cpupri_init(struct cpupri *cp)
{
int i;
memset(cp, 0, sizeof(*cp));
for (i = 0; i < CPUPRI_NR_PRIORITIES; i++) {
struct cpupri_vec *vec = &cp->pri_to_cpu[i];
spin_lock_init(&vec->lock);
vec->count = 0;
cpus_clear(vec->mask);
}
for_each_possible_cpu(i)
cp->cpu_to_pri[i] = CPUPRI_INVALID;
}
kernel/sched_cpupri.h 0 → 100644
View file @ d14c8a68
#ifndef _LINUX_CPUPRI_H
#define _LINUX_CPUPRI_H
#include <linux/sched.h>
#define CPUPRI_NR_PRIORITIES (MAX_RT_PRIO + 2)
#define CPUPRI_NR_PRI_WORDS BITS_TO_LONGS(CPUPRI_NR_PRIORITIES)
#define CPUPRI_INVALID -1
#define CPUPRI_IDLE 0
#define CPUPRI_NORMAL 1
/* values 2-101 are RT priorities 0-99 */
struct cpupri_vec {
spinlock_t lock;
int count;
cpumask_t mask;
};
struct cpupri {
struct cpupri_vec pri_to_cpu[CPUPRI_NR_PRIORITIES];
long pri_active[CPUPRI_NR_PRI_WORDS];
int cpu_to_pri[NR_CPUS];
};
#ifdef CONFIG_SMP
int cpupri_find(struct cpupri *cp,
struct task_struct *p, cpumask_t *lowest_mask);
void cpupri_set(struct cpupri *cp, int cpu, int pri);
void cpupri_init(struct cpupri *cp);
#else
#define cpupri_set(cp, cpu, pri) do { } while (0)
#define cpupri_init() do { } while (0)
#endif
#endif /* _LINUX_CPUPRI_H */
kernel/sched_debug.c
View file @ d14c8a68
......@@ -119,9 +119,7 @@ void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq)
struct sched_entity *last;
unsigned long flags;
#if !defined(CONFIG_CGROUP_SCHED) || !defined(CONFIG_USER_SCHED)
SEQ_printf(m, "\ncfs_rq[%d]:\n", cpu);
#else
#if defined(CONFIG_CGROUP_SCHED) && defined(CONFIG_FAIR_GROUP_SCHED)
char path[128] = "";
struct cgroup *cgroup = NULL;
struct task_group *tg = cfs_rq->tg;
......@@ -133,6 +131,8 @@ void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq)
cgroup_path(cgroup, path, sizeof(path));
SEQ_printf(m, "\ncfs_rq[%d]:%s\n", cpu, path);
#else
SEQ_printf(m, "\ncfs_rq[%d]:\n", cpu);
#endif
SEQ_printf(m, " .%-30s: %Ld.%06ld\n", "exec_clock",
......@@ -162,11 +162,64 @@ void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq)
SEQ_printf(m, " .%-30s: %ld\n", "nr_running", cfs_rq->nr_running);
SEQ_printf(m, " .%-30s: %ld\n", "load", cfs_rq->load.weight);
#ifdef CONFIG_SCHEDSTATS
SEQ_printf(m, " .%-30s: %d\n", "bkl_count",
rq->bkl_count);
#define P(n) SEQ_printf(m, " .%-30s: %d\n", #n, rq->n);
P(yld_exp_empty);
P(yld_act_empty);
P(yld_both_empty);
P(yld_count);
P(sched_switch);
P(sched_count);
P(sched_goidle);
P(ttwu_count);
P(ttwu_local);
P(bkl_count);
#undef P
#endif
SEQ_printf(m, " .%-30s: %ld\n", "nr_spread_over",
cfs_rq->nr_spread_over);
#ifdef CONFIG_FAIR_GROUP_SCHED
#ifdef CONFIG_SMP
SEQ_printf(m, " .%-30s: %lu\n", "shares", cfs_rq->shares);
#endif
#endif
}
void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq)
{
#if defined(CONFIG_CGROUP_SCHED) && defined(CONFIG_RT_GROUP_SCHED)
char path[128] = "";
struct cgroup *cgroup = NULL;
struct task_group *tg = rt_rq->tg;
if (tg)
cgroup = tg->css.cgroup;
if (cgroup)
cgroup_path(cgroup, path, sizeof(path));
SEQ_printf(m, "\nrt_rq[%d]:%s\n", cpu, path);
#else
SEQ_printf(m, "\nrt_rq[%d]:\n", cpu);
#endif
#define P(x) \
SEQ_printf(m, " .%-30s: %Ld\n", #x, (long long)(rt_rq->x))
#define PN(x) \
SEQ_printf(m, " .%-30s: %Ld.%06ld\n", #x, SPLIT_NS(rt_rq->x))
P(rt_nr_running);
P(rt_throttled);
PN(rt_time);
PN(rt_runtime);
#undef PN
#undef P
}
static void print_cpu(struct seq_file *m, int cpu)
......@@ -208,6 +261,7 @@ static void print_cpu(struct seq_file *m, int cpu)
#undef PN
print_cfs_stats(m, cpu);
print_rt_stats(m, cpu);
print_rq(m, rq, cpu);
}
......
kernel/sched_fair.c
View file @ d14c8a68
......@@ -63,13 +63,13 @@ unsigned int __read_mostly sysctl_sched_compat_yield;
/*
* SCHED_OTHER wake-up granularity.
* (default: 10 msec * (1 + ilog(ncpus)), units: nanoseconds)
* (default: 5 msec * (1 + ilog(ncpus)), units: nanoseconds)
*
* This option delays the preemption effects of decoupled workloads
* and reduces their over-scheduling. Synchronous workloads will still
* have immediate wakeup/sleep latencies.
*/
unsigned int sysctl_sched_wakeup_granularity = 10000000UL;
unsigned int sysctl_sched_wakeup_granularity = 5000000UL;
const_debug unsigned int sysctl_sched_migration_cost = 500000UL;
......@@ -333,6 +333,34 @@ int sched_nr_latency_handler(struct ctl_table *table, int write,
}
#endif
/*
* delta *= w / rw
*/
static inline unsigned long
calc_delta_weight(unsigned long delta, struct sched_entity *se)
{
for_each_sched_entity(se) {
delta = calc_delta_mine(delta,
se->load.weight, &cfs_rq_of(se)->load);
}
return delta;
}
/*
* delta *= rw / w
*/
static inline unsigned long
calc_delta_fair(unsigned long delta, struct sched_entity *se)
{
for_each_sched_entity(se) {
delta = calc_delta_mine(delta,
cfs_rq_of(se)->load.weight, &se->load);
}
return delta;
}
/*
* The idea is to set a period in which each task runs once.
*
......@@ -362,47 +390,80 @@ static u64 __sched_period(unsigned long nr_running)
*/
static u64 sched_slice(struct cfs_rq *cfs_rq, struct sched_entity *se)
{
u64 slice = __sched_period(cfs_rq->nr_running);
for_each_sched_entity(se) {
cfs_rq = cfs_rq_of(se);
slice *= se->load.weight;
do_div(slice, cfs_rq->load.weight);
}
return slice;
return calc_delta_weight(__sched_period(cfs_rq->nr_running), se);
}
/*
* We calculate the vruntime slice of a to be inserted task
*
* vs = s/w = p/rw
* vs = s*rw/w = p
*/
static u64 sched_vslice_add(struct cfs_rq *cfs_rq, struct sched_entity *se)
{
unsigned long nr_running = cfs_rq->nr_running;
unsigned long weight;
u64 vslice;
if (!se->on_rq)
nr_running++;
vslice = __sched_period(nr_running);
return __sched_period(nr_running);
}
/*
* The goal of calc_delta_asym() is to be asymmetrically around NICE_0_LOAD, in
* that it favours >=0 over <0.
*
* -20 |
* |
* 0 --------+-------
* .'
* 19 .'
*
*/
static unsigned long
calc_delta_asym(unsigned long delta, struct sched_entity *se)
{
struct load_weight lw = {
.weight = NICE_0_LOAD,
.inv_weight = 1UL << (WMULT_SHIFT-NICE_0_SHIFT)
};
for_each_sched_entity(se) {
cfs_rq = cfs_rq_of(se);
struct load_weight *se_lw = &se->load;
unsigned long rw = cfs_rq_of(se)->load.weight;
weight = cfs_rq->load.weight;
if (!se->on_rq)
weight += se->load.weight;
#ifdef CONFIG_FAIR_SCHED_GROUP
struct cfs_rq *cfs_rq = se->my_q;
struct task_group *tg = NULL
if (cfs_rq)
tg = cfs_rq->tg;
if (tg && tg->shares < NICE_0_LOAD) {
/*
* scale shares to what it would have been had
* tg->weight been NICE_0_LOAD:
*
* weight = 1024 * shares / tg->weight
*/
lw.weight *= se->load.weight;
lw.weight /= tg->shares;
vslice *= NICE_0_LOAD;
do_div(vslice, weight);
lw.inv_weight = 0;
se_lw = &lw;
rw += lw.weight - se->load.weight;
} else
#endif
if (se->load.weight < NICE_0_LOAD) {
se_lw = &lw;
rw += NICE_0_LOAD - se->load.weight;
}
return vslice;
delta = calc_delta_mine(delta, rw, se_lw);
}
return delta;
}
/*
......@@ -419,11 +480,7 @@ __update_curr(struct cfs_rq *cfs_rq, struct sched_entity *curr,
curr->sum_exec_runtime += delta_exec;
schedstat_add(cfs_rq, exec_clock, delta_exec);
delta_exec_weighted = delta_exec;
if (unlikely(curr->load.weight != NICE_0_LOAD)) {
delta_exec_weighted = calc_delta_fair(delta_exec_weighted,
&curr->load);
}
delta_exec_weighted = calc_delta_fair(delta_exec, curr);
curr->vruntime += delta_exec_weighted;
}
......@@ -510,10 +567,27 @@ update_stats_curr_start(struct cfs_rq *cfs_rq, struct sched_entity *se)
* Scheduling class queueing methods:
*/
#if defined CONFIG_SMP && defined CONFIG_FAIR_GROUP_SCHED
static void
add_cfs_task_weight(struct cfs_rq *cfs_rq, unsigned long weight)
{
cfs_rq->task_weight += weight;
}
#else
static inline void
add_cfs_task_weight(struct cfs_rq *cfs_rq, unsigned long weight)
{
}
#endif
static void
account_entity_enqueue(struct cfs_rq *cfs_rq, struct sched_entity *se)
{
update_load_add(&cfs_rq->load, se->load.weight);
if (!parent_entity(se))
inc_cpu_load(rq_of(cfs_rq), se->load.weight);
if (entity_is_task(se))
add_cfs_task_weight(cfs_rq, se->load.weight);
cfs_rq->nr_running++;
se->on_rq = 1;
list_add(&se->group_node, &cfs_rq->tasks);
......@@ -523,6 +597,10 @@ static void
account_entity_dequeue(struct cfs_rq *cfs_rq, struct sched_entity *se)
{
update_load_sub(&cfs_rq->load, se->load.weight);
if (!parent_entity(se))
dec_cpu_load(rq_of(cfs_rq), se->load.weight);
if (entity_is_task(se))
add_cfs_task_weight(cfs_rq, -se->load.weight);
cfs_rq->nr_running--;
se->on_rq = 0;
list_del_init(&se->group_node);
......@@ -609,8 +687,17 @@ place_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int initial)
if (!initial) {
/* sleeps upto a single latency don't count. */
if (sched_feat(NEW_FAIR_SLEEPERS))
vruntime -= sysctl_sched_latency;
if (sched_feat(NEW_FAIR_SLEEPERS)) {
unsigned long thresh = sysctl_sched_latency;
/*
* convert the sleeper threshold into virtual time
*/
if (sched_feat(NORMALIZED_SLEEPER))
thresh = calc_delta_fair(thresh, se);
vruntime -= thresh;
}
/* ensure we never gain time by being placed backwards. */
vruntime = max_vruntime(se->vruntime, vruntime);
......@@ -639,21 +726,6 @@ enqueue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int wakeup)
__enqueue_entity(cfs_rq, se);
}
static void update_avg(u64 *avg, u64 sample)
{
s64 diff = sample - *avg;
*avg += diff >> 3;
}
static void update_avg_stats(struct cfs_rq *cfs_rq, struct sched_entity *se)
{
if (!se->last_wakeup)
return;
update_avg(&se->avg_overlap, se->sum_exec_runtime - se->last_wakeup);
se->last_wakeup = 0;
}
static void
dequeue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int sleep)
{
......@@ -664,7 +736,6 @@ dequeue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int sleep)
update_stats_dequeue(cfs_rq, se);
if (sleep) {
update_avg_stats(cfs_rq, se);
#ifdef CONFIG_SCHEDSTATS
if (entity_is_task(se)) {
struct task_struct *tsk = task_of(se);
......@@ -726,17 +797,16 @@ set_next_entity(struct cfs_rq *cfs_rq, struct sched_entity *se)
se->prev_sum_exec_runtime = se->sum_exec_runtime;
}
static int
wakeup_preempt_entity(struct sched_entity *curr, struct sched_entity *se);
static struct sched_entity *
pick_next(struct cfs_rq *cfs_rq, struct sched_entity *se)
{
if (!cfs_rq->next)
return se;
struct rq *rq = rq_of(cfs_rq);
u64 pair_slice = rq->clock - cfs_rq->pair_start;
if (wakeup_preempt_entity(cfs_rq->next, se) != 0)
if (!cfs_rq->next || pair_slice > sched_slice(cfs_rq, cfs_rq->next)) {
cfs_rq->pair_start = rq->clock;
return se;
}
return cfs_rq->next;
}
......@@ -835,7 +905,7 @@ static void hrtick_start_fair(struct rq *rq, struct task_struct *p)
hrtick_start(rq, delta, requeue);
}
}
#else
#else /* !CONFIG_SCHED_HRTICK */
static inline void
hrtick_start_fair(struct rq *rq, struct task_struct *p)
{
......@@ -976,7 +1046,7 @@ static int wake_idle(int cpu, struct task_struct *p)
}
return cpu;
}
#else
#else /* !ARCH_HAS_SCHED_WAKE_IDLE*/
static inline int wake_idle(int cpu, struct task_struct *p)
{
return cpu;
......@@ -987,6 +1057,89 @@ static inline int wake_idle(int cpu, struct task_struct *p)
static const struct sched_class fair_sched_class;
#ifdef CONFIG_FAIR_GROUP_SCHED
/*
* effective_load() calculates the load change as seen from the root_task_group
*
* Adding load to a group doesn't make a group heavier, but can cause movement
* of group shares between cpus. Assuming the shares were perfectly aligned one
* can calculate the shift in shares.
*
* The problem is that perfectly aligning the shares is rather expensive, hence
* we try to avoid doing that too often - see update_shares(), which ratelimits
* this change.
*
* We compensate this by not only taking the current delta into account, but
* also considering the delta between when the shares were last adjusted and
* now.
*
* We still saw a performance dip, some tracing learned us that between
* cgroup:/ and cgroup:/foo balancing the number of affine wakeups increased
* significantly. Therefore try to bias the error in direction of failing
* the affine wakeup.
*
*/
static long effective_load(struct task_group *tg, int cpu,
long wl, long wg)
{
struct sched_entity *se = tg->se[cpu];
long more_w;
if (!tg->parent)
return wl;
/*
* By not taking the decrease of shares on the other cpu into
* account our error leans towards reducing the affine wakeups.
*/
if (!wl && sched_feat(ASYM_EFF_LOAD))
return wl;
/*
* Instead of using this increment, also add the difference
* between when the shares were last updated and now.
*/
more_w = se->my_q->load.weight - se->my_q->rq_weight;
wl += more_w;
wg += more_w;
for_each_sched_entity(se) {
#define D(n) (likely(n) ? (n) : 1)
long S, rw, s, a, b;
S = se->my_q->tg->shares;
s = se->my_q->shares;
rw = se->my_q->rq_weight;
a = S*(rw + wl);
b = S*rw + s*wg;
wl = s*(a-b)/D(b);
/*
* Assume the group is already running and will
* thus already be accounted for in the weight.
*
* That is, moving shares between CPUs, does not
* alter the group weight.
*/
wg = 0;
#undef D
}
return wl;
}
#else
static inline unsigned long effective_load(struct task_group *tg, int cpu,
unsigned long wl, unsigned long wg)
{
return wl;
}
#endif
static int
wake_affine(struct rq *rq, struct sched_domain *this_sd, struct rq *this_rq,
struct task_struct *p, int prev_cpu, int this_cpu, int sync,
......@@ -994,8 +1147,10 @@ wake_affine(struct rq *rq, struct sched_domain *this_sd, struct rq *this_rq,
unsigned int imbalance)
{
struct task_struct *curr = this_rq->curr;
struct task_group *tg;
unsigned long tl = this_load;
unsigned long tl_per_task;
unsigned long weight;
int balanced;
if (!(this_sd->flags & SD_WAKE_AFFINE) || !sched_feat(AFFINE_WAKEUPS))
......@@ -1006,17 +1161,26 @@ wake_affine(struct rq *rq, struct sched_domain *this_sd, struct rq *this_rq,
* effect of the currently running task from the load
* of the current CPU:
*/
if (sync)
tl -= current->se.load.weight;
if (sync) {
tg = task_group(current);
weight = current->se.load.weight;
tl += effective_load(tg, this_cpu, -weight, -weight);
load += effective_load(tg, prev_cpu, 0, -weight);
}
balanced = 100*(tl + p->se.load.weight) <= imbalance*load;
tg = task_group(p);
weight = p->se.load.weight;
balanced = 100*(tl + effective_load(tg, this_cpu, weight, weight)) <=
imbalance*(load + effective_load(tg, prev_cpu, 0, weight));
/*
* If the currently running task will sleep within
* a reasonable amount of time then attract this newly
* woken task:
*/
if (sync && balanced && curr->sched_class == &fair_sched_class) {
if (sync && balanced) {
if (curr->se.avg_overlap < sysctl_sched_migration_cost &&
p->se.avg_overlap < sysctl_sched_migration_cost)
return 1;
......@@ -1111,11 +1275,13 @@ static unsigned long wakeup_gran(struct sched_entity *se)
unsigned long gran = sysctl_sched_wakeup_granularity;
/*
* More easily preempt - nice tasks, while not making
* it harder for + nice tasks.
* More easily preempt - nice tasks, while not making it harder for
* + nice tasks.
*/
if (unlikely(se->load.weight > NICE_0_LOAD))
gran = calc_delta_fair(gran, &se->load);
if (sched_feat(ASYM_GRAN))
gran = calc_delta_asym(sysctl_sched_wakeup_granularity, se);
else
gran = calc_delta_fair(sysctl_sched_wakeup_granularity, se);
return gran;
}
......@@ -1177,7 +1343,6 @@ static void check_preempt_wakeup(struct rq *rq, struct task_struct *p)
return;
}
se->last_wakeup = se->sum_exec_runtime;
if (unlikely(se == pse))
return;
......@@ -1275,23 +1440,18 @@ __load_balance_iterator(struct cfs_rq *cfs_rq, struct list_head *next)
struct task_struct *p = NULL;
struct sched_entity *se;
if (next == &cfs_rq->tasks)
return NULL;
/* Skip over entities that are not tasks */
do {
while (next != &cfs_rq->tasks) {
se = list_entry(next, struct sched_entity, group_node);
next = next->next;
} while (next != &cfs_rq->tasks && !entity_is_task(se));
if (next == &cfs_rq->tasks)
return NULL;
cfs_rq->balance_iterator = next;
if (entity_is_task(se))
/* Skip over entities that are not tasks */
if (entity_is_task(se)) {
p = task_of(se);
break;
}
}
cfs_rq->balance_iterator = next;
return p;
}
......@@ -1309,75 +1469,82 @@ static struct task_struct *load_balance_next_fair(void *arg)
return __load_balance_iterator(cfs_rq, cfs_rq->balance_iterator);
}
#ifdef CONFIG_FAIR_GROUP_SCHED
static int cfs_rq_best_prio(struct cfs_rq *cfs_rq)
static unsigned long
__load_balance_fair(struct rq *this_rq, int this_cpu, struct rq *busiest,
unsigned long max_load_move, struct sched_domain *sd,
enum cpu_idle_type idle, int *all_pinned, int *this_best_prio,
struct cfs_rq *cfs_rq)
{
struct sched_entity *curr;
struct task_struct *p;
if (!cfs_rq->nr_running || !first_fair(cfs_rq))
return MAX_PRIO;
curr = cfs_rq->curr;
if (!curr)
curr = __pick_next_entity(cfs_rq);
struct rq_iterator cfs_rq_iterator;
p = task_of(curr);
cfs_rq_iterator.start = load_balance_start_fair;
cfs_rq_iterator.next = load_balance_next_fair;
cfs_rq_iterator.arg = cfs_rq;
return p->prio;
return balance_tasks(this_rq, this_cpu, busiest,
max_load_move, sd, idle, all_pinned,
this_best_prio, &cfs_rq_iterator);
}
#endif
#ifdef CONFIG_FAIR_GROUP_SCHED
static unsigned long
load_balance_fair(struct rq *this_rq, int this_cpu, struct rq *busiest,
unsigned long max_load_move,
struct sched_domain *sd, enum cpu_idle_type idle,
int *all_pinned, int *this_best_prio)
{
struct cfs_rq *busy_cfs_rq;
long rem_load_move = max_load_move;
struct rq_iterator cfs_rq_iterator;
cfs_rq_iterator.start = load_balance_start_fair;
cfs_rq_iterator.next = load_balance_next_fair;
int busiest_cpu = cpu_of(busiest);
struct task_group *tg;
for_each_leaf_cfs_rq(busiest, busy_cfs_rq) {
#ifdef CONFIG_FAIR_GROUP_SCHED
struct cfs_rq *this_cfs_rq;
long imbalance;
unsigned long maxload;
rcu_read_lock();
update_h_load(busiest_cpu);
this_cfs_rq = cpu_cfs_rq(busy_cfs_rq, this_cpu);
list_for_each_entry(tg, &task_groups, list) {
struct cfs_rq *busiest_cfs_rq = tg->cfs_rq[busiest_cpu];
unsigned long busiest_h_load = busiest_cfs_rq->h_load;
unsigned long busiest_weight = busiest_cfs_rq->load.weight;
u64 rem_load, moved_load;
imbalance = busy_cfs_rq->load.weight - this_cfs_rq->load.weight;
/* Don't pull if this_cfs_rq has more load than busy_cfs_rq */
if (imbalance <= 0)
/*
* empty group
*/
if (!busiest_cfs_rq->task_weight)
continue;
/* Don't pull more than imbalance/2 */
imbalance /= 2;
maxload = min(rem_load_move, imbalance);
rem_load = (u64)rem_load_move * busiest_weight;
rem_load = div_u64(rem_load, busiest_h_load + 1);
*this_best_prio = cfs_rq_best_prio(this_cfs_rq);
#else
# define maxload rem_load_move
#endif
/*
* pass busy_cfs_rq argument into
* load_balance_[start|next]_fair iterators
*/
cfs_rq_iterator.arg = busy_cfs_rq;
rem_load_move -= balance_tasks(this_rq, this_cpu, busiest,
maxload, sd, idle, all_pinned,
this_best_prio,
&cfs_rq_iterator);
moved_load = __load_balance_fair(this_rq, this_cpu, busiest,
rem_load, sd, idle, all_pinned, this_best_prio,
tg->cfs_rq[busiest_cpu]);
if (rem_load_move <= 0)
if (!moved_load)
continue;
moved_load *= busiest_h_load;
moved_load = div_u64(moved_load, busiest_weight + 1);
rem_load_move -= moved_load;
if (rem_load_move < 0)
break;
}
rcu_read_unlock();
return max_load_move - rem_load_move;
}
#else
static unsigned long
load_balance_fair(struct rq *this_rq, int this_cpu, struct rq *busiest,
unsigned long max_load_move,
struct sched_domain *sd, enum cpu_idle_type idle,
int *all_pinned, int *this_best_prio)
{
return __load_balance_fair(this_rq, this_cpu, busiest,
max_load_move, sd, idle, all_pinned,
this_best_prio, &busiest->cfs);
}
#endif
static int
move_one_task_fair(struct rq *this_rq, int this_cpu, struct rq *busiest,
......@@ -1402,7 +1569,7 @@ move_one_task_fair(struct rq *this_rq, int this_cpu, struct rq *busiest,
return 0;
}
#endif
#endif /* CONFIG_SMP */
/*
* scheduler tick hitting a task of our scheduling class:
......
kernel/sched_features.h
View file @ d14c8a68
SCHED_FEAT(NEW_FAIR_SLEEPERS, 1)
SCHED_FEAT(NORMALIZED_SLEEPER, 1)
SCHED_FEAT(WAKEUP_PREEMPT, 1)
SCHED_FEAT(START_DEBIT, 1)
SCHED_FEAT(AFFINE_WAKEUPS, 1)
......@@ -6,5 +7,7 @@ SCHED_FEAT(CACHE_HOT_BUDDY, 1)
SCHED_FEAT(SYNC_WAKEUPS, 1)
SCHED_FEAT(HRTICK, 1)
SCHED_FEAT(DOUBLE_TICK, 0)
SCHED_FEAT(NORMALIZED_SLEEPER, 1)
SCHED_FEAT(DEADLINE, 1)
SCHED_FEAT(ASYM_GRAN, 1)
SCHED_FEAT(LB_BIAS, 0)
SCHED_FEAT(LB_WAKEUP_UPDATE, 1)
SCHED_FEAT(ASYM_EFF_LOAD, 1)
kernel/sched_rt.c
View file @ d14c8a68
......@@ -12,6 +12,9 @@ static inline int rt_overloaded(struct rq *rq)
static inline void rt_set_overload(struct rq *rq)
{
if (!rq->online)
return;
cpu_set(rq->cpu, rq->rd->rto_mask);
/*
* Make sure the mask is visible before we set
......@@ -26,6 +29,9 @@ static inline void rt_set_overload(struct rq *rq)
static inline void rt_clear_overload(struct rq *rq)
{
if (!rq->online)
return;
/* the order here really doesn't matter */
atomic_dec(&rq->rd->rto_count);
cpu_clear(rq->cpu, rq->rd->rto_mask);
......@@ -155,7 +161,7 @@ static inline struct rt_bandwidth *sched_rt_bandwidth(struct rt_rq *rt_rq)
return &rt_rq->tg->rt_bandwidth;
}
#else
#else /* !CONFIG_RT_GROUP_SCHED */
static inline u64 sched_rt_runtime(struct rt_rq *rt_rq)
{
......@@ -220,49 +226,10 @@ static inline struct rt_bandwidth *sched_rt_bandwidth(struct rt_rq *rt_rq)
return &def_rt_bandwidth;
}
#endif
static int do_sched_rt_period_timer(struct rt_bandwidth *rt_b, int overrun)
{
int i, idle = 1;
cpumask_t span;
if (rt_b->rt_runtime == RUNTIME_INF)
return 1;
span = sched_rt_period_mask();
for_each_cpu_mask(i, span) {
int enqueue = 0;
struct rt_rq *rt_rq = sched_rt_period_rt_rq(rt_b, i);
struct rq *rq = rq_of_rt_rq(rt_rq);
spin_lock(&rq->lock);
if (rt_rq->rt_time) {
u64 runtime;
spin_lock(&rt_rq->rt_runtime_lock);
runtime = rt_rq->rt_runtime;
rt_rq->rt_time -= min(rt_rq->rt_time, overrun*runtime);
if (rt_rq->rt_throttled && rt_rq->rt_time < runtime) {
rt_rq->rt_throttled = 0;
enqueue = 1;
}
if (rt_rq->rt_time || rt_rq->rt_nr_running)
idle = 0;
spin_unlock(&rt_rq->rt_runtime_lock);
} else if (rt_rq->rt_nr_running)
idle = 0;
if (enqueue)
sched_rt_rq_enqueue(rt_rq);
spin_unlock(&rq->lock);
}
return idle;
}
#endif /* CONFIG_RT_GROUP_SCHED */
#ifdef CONFIG_SMP
static int balance_runtime(struct rt_rq *rt_rq)
static int do_balance_runtime(struct rt_rq *rt_rq)
{
struct rt_bandwidth *rt_b = sched_rt_bandwidth(rt_rq);
struct root_domain *rd = cpu_rq(smp_processor_id())->rd;
......@@ -281,6 +248,9 @@ static int balance_runtime(struct rt_rq *rt_rq)
continue;
spin_lock(&iter->rt_runtime_lock);
if (iter->rt_runtime == RUNTIME_INF)
goto next;
diff = iter->rt_runtime - iter->rt_time;
if (diff > 0) {
do_div(diff, weight);
......@@ -294,13 +264,163 @@ static int balance_runtime(struct rt_rq *rt_rq)
break;
}
}
next:
spin_unlock(&iter->rt_runtime_lock);
}
spin_unlock(&rt_b->rt_runtime_lock);
return more;
}
#endif
static void __disable_runtime(struct rq *rq)
{
struct root_domain *rd = rq->rd;
struct rt_rq *rt_rq;
if (unlikely(!scheduler_running))
return;
for_each_leaf_rt_rq(rt_rq, rq) {
struct rt_bandwidth *rt_b = sched_rt_bandwidth(rt_rq);
s64 want;
int i;
spin_lock(&rt_b->rt_runtime_lock);
spin_lock(&rt_rq->rt_runtime_lock);
if (rt_rq->rt_runtime == RUNTIME_INF ||
rt_rq->rt_runtime == rt_b->rt_runtime)
goto balanced;
spin_unlock(&rt_rq->rt_runtime_lock);
want = rt_b->rt_runtime - rt_rq->rt_runtime;
for_each_cpu_mask(i, rd->span) {
struct rt_rq *iter = sched_rt_period_rt_rq(rt_b, i);
s64 diff;
if (iter == rt_rq)
continue;
spin_lock(&iter->rt_runtime_lock);
if (want > 0) {
diff = min_t(s64, iter->rt_runtime, want);
iter->rt_runtime -= diff;
want -= diff;
} else {
iter->rt_runtime -= want;
want -= want;
}
spin_unlock(&iter->rt_runtime_lock);
if (!want)
break;
}
spin_lock(&rt_rq->rt_runtime_lock);
BUG_ON(want);
balanced:
rt_rq->rt_runtime = RUNTIME_INF;
spin_unlock(&rt_rq->rt_runtime_lock);
spin_unlock(&rt_b->rt_runtime_lock);
}
}
static void disable_runtime(struct rq *rq)
{
unsigned long flags;
spin_lock_irqsave(&rq->lock, flags);
__disable_runtime(rq);
spin_unlock_irqrestore(&rq->lock, flags);
}
static void __enable_runtime(struct rq *rq)
{
struct rt_rq *rt_rq;
if (unlikely(!scheduler_running))
return;
for_each_leaf_rt_rq(rt_rq, rq) {
struct rt_bandwidth *rt_b = sched_rt_bandwidth(rt_rq);
spin_lock(&rt_b->rt_runtime_lock);
spin_lock(&rt_rq->rt_runtime_lock);
rt_rq->rt_runtime = rt_b->rt_runtime;
rt_rq->rt_time = 0;
spin_unlock(&rt_rq->rt_runtime_lock);
spin_unlock(&rt_b->rt_runtime_lock);
}
}
static void enable_runtime(struct rq *rq)
{
unsigned long flags;
spin_lock_irqsave(&rq->lock, flags);
__enable_runtime(rq);
spin_unlock_irqrestore(&rq->lock, flags);
}
static int balance_runtime(struct rt_rq *rt_rq)
{
int more = 0;
if (rt_rq->rt_time > rt_rq->rt_runtime) {
spin_unlock(&rt_rq->rt_runtime_lock);
more = do_balance_runtime(rt_rq);
spin_lock(&rt_rq->rt_runtime_lock);
}
return more;
}
#else /* !CONFIG_SMP */
static inline int balance_runtime(struct rt_rq *rt_rq)
{
return 0;
}
#endif /* CONFIG_SMP */
static int do_sched_rt_period_timer(struct rt_bandwidth *rt_b, int overrun)
{
int i, idle = 1;
cpumask_t span;
if (rt_b->rt_runtime == RUNTIME_INF)
return 1;
span = sched_rt_period_mask();
for_each_cpu_mask(i, span) {
int enqueue = 0;
struct rt_rq *rt_rq = sched_rt_period_rt_rq(rt_b, i);
struct rq *rq = rq_of_rt_rq(rt_rq);
spin_lock(&rq->lock);
if (rt_rq->rt_time) {
u64 runtime;
spin_lock(&rt_rq->rt_runtime_lock);
if (rt_rq->rt_throttled)
balance_runtime(rt_rq);
runtime = rt_rq->rt_runtime;
rt_rq->rt_time -= min(rt_rq->rt_time, overrun*runtime);
if (rt_rq->rt_throttled && rt_rq->rt_time < runtime) {
rt_rq->rt_throttled = 0;
enqueue = 1;
}
if (rt_rq->rt_time || rt_rq->rt_nr_running)
idle = 0;
spin_unlock(&rt_rq->rt_runtime_lock);
} else if (rt_rq->rt_nr_running)
idle = 0;
if (enqueue)
sched_rt_rq_enqueue(rt_rq);
spin_unlock(&rq->lock);
}
return idle;
}
static inline int rt_se_prio(struct sched_rt_entity *rt_se)
{
......@@ -327,18 +447,10 @@ static int sched_rt_runtime_exceeded(struct rt_rq *rt_rq)
if (sched_rt_runtime(rt_rq) >= sched_rt_period(rt_rq))
return 0;
#ifdef CONFIG_SMP
if (rt_rq->rt_time > runtime) {
int more;
spin_unlock(&rt_rq->rt_runtime_lock);
more = balance_runtime(rt_rq);
spin_lock(&rt_rq->rt_runtime_lock);
if (more)
balance_runtime(rt_rq);
runtime = sched_rt_runtime(rt_rq);
}
#endif
if (runtime == RUNTIME_INF)
return 0;
if (rt_rq->rt_time > runtime) {
rt_rq->rt_throttled = 1;
......@@ -392,12 +504,21 @@ void inc_rt_tasks(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq)
WARN_ON(!rt_prio(rt_se_prio(rt_se)));
rt_rq->rt_nr_running++;
#if defined CONFIG_SMP || defined CONFIG_RT_GROUP_SCHED
if (rt_se_prio(rt_se) < rt_rq->highest_prio)
if (rt_se_prio(rt_se) < rt_rq->highest_prio) {
struct rq *rq = rq_of_rt_rq(rt_rq);
rt_rq->highest_prio = rt_se_prio(rt_se);
#ifdef CONFIG_SMP
if (rq->online)
cpupri_set(&rq->rd->cpupri, rq->cpu,
rt_se_prio(rt_se));
#endif
}
#endif
#ifdef CONFIG_SMP
if (rt_se->nr_cpus_allowed > 1) {
struct rq *rq = rq_of_rt_rq(rt_rq);
rq->rt.rt_nr_migratory++;
}
......@@ -417,6 +538,10 @@ void inc_rt_tasks(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq)
static inline
void dec_rt_tasks(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq)
{
#ifdef CONFIG_SMP
int highest_prio = rt_rq->highest_prio;
#endif
WARN_ON(!rt_prio(rt_se_prio(rt_se)));
WARN_ON(!rt_rq->rt_nr_running);
rt_rq->rt_nr_running--;
......@@ -440,6 +565,14 @@ void dec_rt_tasks(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq)
rq->rt.rt_nr_migratory--;
}
if (rt_rq->highest_prio != highest_prio) {
struct rq *rq = rq_of_rt_rq(rt_rq);
if (rq->online)
cpupri_set(&rq->rd->cpupri, rq->cpu,
rt_rq->highest_prio);
}
update_rt_migration(rq_of_rt_rq(rt_rq));
#endif /* CONFIG_SMP */
#ifdef CONFIG_RT_GROUP_SCHED
......@@ -455,6 +588,7 @@ static void __enqueue_rt_entity(struct sched_rt_entity *rt_se)
struct rt_rq *rt_rq = rt_rq_of_se(rt_se);
struct rt_prio_array *array = &rt_rq->active;
struct rt_rq *group_rq = group_rt_rq(rt_se);
struct list_head *queue = array->queue + rt_se_prio(rt_se);
/*
* Don't enqueue the group if its throttled, or when empty.
......@@ -465,7 +599,11 @@ static void __enqueue_rt_entity(struct sched_rt_entity *rt_se)
if (group_rq && (rt_rq_throttled(group_rq) || !group_rq->rt_nr_running))
return;
list_add_tail(&rt_se->run_list, array->queue + rt_se_prio(rt_se));
if (rt_se->nr_cpus_allowed == 1)
list_add(&rt_se->run_list, queue);
else
list_add_tail(&rt_se->run_list, queue);
__set_bit(rt_se_prio(rt_se), array->bitmap);
inc_rt_tasks(rt_se, rt_rq);
......@@ -532,6 +670,8 @@ static void enqueue_task_rt(struct rq *rq, struct task_struct *p, int wakeup)
rt_se->timeout = 0;
enqueue_rt_entity(rt_se);
inc_cpu_load(rq, p->se.load.weight);
}
static void dequeue_task_rt(struct rq *rq, struct task_struct *p, int sleep)
......@@ -540,6 +680,8 @@ static void dequeue_task_rt(struct rq *rq, struct task_struct *p, int sleep)
update_curr_rt(rq);
dequeue_rt_entity(rt_se);
dec_cpu_load(rq, p->se.load.weight);
}
/*
......@@ -550,10 +692,12 @@ static
void requeue_rt_entity(struct rt_rq *rt_rq, struct sched_rt_entity *rt_se)
{
struct rt_prio_array *array = &rt_rq->active;
struct list_head *queue = array->queue + rt_se_prio(rt_se);
if (on_rt_rq(rt_se))
list_move_tail(&rt_se->run_list, queue);
if (on_rt_rq(rt_se)) {
list_del_init(&rt_se->run_list);
list_add_tail(&rt_se->run_list,
array->queue + rt_se_prio(rt_se));
}
}
static void requeue_task_rt(struct rq *rq, struct task_struct *p)
......@@ -616,8 +760,37 @@ static int select_task_rq_rt(struct task_struct *p, int sync)
*/
static void check_preempt_curr_rt(struct rq *rq, struct task_struct *p)
{
if (p->prio < rq->curr->prio)
if (p->prio < rq->curr->prio) {
resched_task(rq->curr);
return;
}
#ifdef CONFIG_SMP
/*
* If:
*
* - the newly woken task is of equal priority to the current task
* - the newly woken task is non-migratable while current is migratable
* - current will be preempted on the next reschedule
*
* we should check to see if current can readily move to a different
* cpu. If so, we will reschedule to allow the push logic to try
* to move current somewhere else, making room for our non-migratable
* task.
*/
if((p->prio == rq->curr->prio)
&& p->rt.nr_cpus_allowed == 1
&& rq->curr->rt.nr_cpus_allowed != 1) {
cpumask_t mask;
if (cpupri_find(&rq->rd->cpupri, rq->curr, &mask))
/*
* There appears to be other cpus that can accept
* current, so lets reschedule to try and push it away
*/
resched_task(rq->curr);
}
#endif
}
static struct sched_rt_entity *pick_next_rt_entity(struct rq *rq,
......@@ -720,73 +893,6 @@ static struct task_struct *pick_next_highest_task_rt(struct rq *rq, int cpu)
static DEFINE_PER_CPU(cpumask_t, local_cpu_mask);
static int find_lowest_cpus(struct task_struct *task, cpumask_t *lowest_mask)
{
int lowest_prio = -1;
int lowest_cpu = -1;
int count = 0;
int cpu;
cpus_and(*lowest_mask, task_rq(task)->rd->online, task->cpus_allowed);
/*
* Scan each rq for the lowest prio.
*/
for_each_cpu_mask(cpu, *lowest_mask) {
struct rq *rq = cpu_rq(cpu);
/* We look for lowest RT prio or non-rt CPU */
if (rq->rt.highest_prio >= MAX_RT_PRIO) {
/*
* if we already found a low RT queue
* and now we found this non-rt queue
* clear the mask and set our bit.
* Otherwise just return the queue as is
* and the count==1 will cause the algorithm
* to use the first bit found.
*/
if (lowest_cpu != -1) {
cpus_clear(*lowest_mask);
cpu_set(rq->cpu, *lowest_mask);
}
return 1;
}
/* no locking for now */
if ((rq->rt.highest_prio > task->prio)
&& (rq->rt.highest_prio >= lowest_prio)) {
if (rq->rt.highest_prio > lowest_prio) {
/* new low - clear old data */
lowest_prio = rq->rt.highest_prio;
lowest_cpu = cpu;
count = 0;
}
count++;
} else
cpu_clear(cpu, *lowest_mask);
}
/*
* Clear out all the set bits that represent
* runqueues that were of higher prio than
* the lowest_prio.
*/
if (lowest_cpu > 0) {
/*
* Perhaps we could add another cpumask op to
* zero out bits. Like cpu_zero_bits(cpumask, nrbits);
* Then that could be optimized to use memset and such.
*/
for_each_cpu_mask(cpu, *lowest_mask) {
if (cpu >= lowest_cpu)
break;
cpu_clear(cpu, *lowest_mask);
}
}
return count;
}
static inline int pick_optimal_cpu(int this_cpu, cpumask_t *mask)
{
int first;
......@@ -808,17 +914,12 @@ static int find_lowest_rq(struct task_struct *task)
cpumask_t *lowest_mask = &__get_cpu_var(local_cpu_mask);
int this_cpu = smp_processor_id();
int cpu = task_cpu(task);
int count = find_lowest_cpus(task, lowest_mask);
if (!count)
return -1; /* No targets found */
if (task->rt.nr_cpus_allowed == 1)
return -1; /* No other targets possible */
/*
* There is no sense in performing an optimal search if only one
* target is found.
*/
if (count == 1)
return first_cpu(*lowest_mask);
if (!cpupri_find(&task_rq(task)->rd->cpupri, task, lowest_mask))
return -1; /* No targets found */
/*
* At this point we have built a mask of cpus representing the
......@@ -1163,17 +1264,25 @@ static void set_cpus_allowed_rt(struct task_struct *p,
}
/* Assumes rq->lock is held */
static void join_domain_rt(struct rq *rq)
static void rq_online_rt(struct rq *rq)
{
if (rq->rt.overloaded)
rt_set_overload(rq);
__enable_runtime(rq);
cpupri_set(&rq->rd->cpupri, rq->cpu, rq->rt.highest_prio);
}
/* Assumes rq->lock is held */
static void leave_domain_rt(struct rq *rq)
static void rq_offline_rt(struct rq *rq)
{
if (rq->rt.overloaded)
rt_clear_overload(rq);
__disable_runtime(rq);
cpupri_set(&rq->rd->cpupri, rq->cpu, CPUPRI_INVALID);
}
/*
......@@ -1336,8 +1445,8 @@ static const struct sched_class rt_sched_class = {
.load_balance = load_balance_rt,
.move_one_task = move_one_task_rt,
.set_cpus_allowed = set_cpus_allowed_rt,
.join_domain = join_domain_rt,
.leave_domain = leave_domain_rt,
.rq_online = rq_online_rt,
.rq_offline = rq_offline_rt,
.pre_schedule = pre_schedule_rt,
.post_schedule = post_schedule_rt,
.task_wake_up = task_wake_up_rt,
......@@ -1350,3 +1459,17 @@ static const struct sched_class rt_sched_class = {
.prio_changed = prio_changed_rt,
.switched_to = switched_to_rt,
};
#ifdef CONFIG_SCHED_DEBUG
extern void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq);
static void print_rt_stats(struct seq_file *m, int cpu)
{
struct rt_rq *rt_rq;
rcu_read_lock();
for_each_leaf_rt_rq(rt_rq, cpu_rq(cpu))
print_rt_rq(m, cpu, rt_rq);
rcu_read_unlock();
}
#endif /* CONFIG_SCHED_DEBUG */
kernel/sched_stats.h
View file @ d14c8a68
......@@ -118,6 +118,13 @@ rq_sched_info_depart(struct rq *rq, unsigned long long delta)
if (rq)
rq->rq_sched_info.cpu_time += delta;
}
static inline void
rq_sched_info_dequeued(struct rq *rq, unsigned long long delta)
{
if (rq)
rq->rq_sched_info.run_delay += delta;
}
# define schedstat_inc(rq, field) do { (rq)->field++; } while (0)
# define schedstat_add(rq, field, amt) do { (rq)->field += (amt); } while (0)
# define schedstat_set(var, val) do { var = (val); } while (0)
......@@ -126,6 +133,9 @@ static inline void
rq_sched_info_arrive(struct rq *rq, unsigned long long delta)
{}
static inline void
rq_sched_info_dequeued(struct rq *rq, unsigned long long delta)
{}
static inline void
rq_sched_info_depart(struct rq *rq, unsigned long long delta)
{}
# define schedstat_inc(rq, field) do { } while (0)
......@@ -134,6 +144,11 @@ rq_sched_info_depart(struct rq *rq, unsigned long long delta)
#endif
#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
static inline void sched_info_reset_dequeued(struct task_struct *t)
{
t->sched_info.last_queued = 0;
}
/*
* Called when a process is dequeued from the active array and given
* the cpu. We should note that with the exception of interactive
......@@ -143,15 +158,22 @@ rq_sched_info_depart(struct rq *rq, unsigned long long delta)
* active queue, thus delaying tasks in the expired queue from running;
* see scheduler_tick()).
*
* This function is only called from sched_info_arrive(), rather than
* dequeue_task(). Even though a task may be queued and dequeued multiple
* times as it is shuffled about, we're really interested in knowing how
* long it was from the *first* time it was queued to the time that it
* finally hit a cpu.
* Though we are interested in knowing how long it was from the *first* time a
* task was queued to the time that it finally hit a cpu, we call this routine
* from dequeue_task() to account for possible rq->clock skew across cpus. The
* delta taken on each cpu would annul the skew.
*/
static inline void sched_info_dequeued(struct task_struct *t)
{
t->sched_info.last_queued = 0;
unsigned long long now = task_rq(t)->clock, delta = 0;
if (unlikely(sched_info_on()))
if (t->sched_info.last_queued)
delta = now - t->sched_info.last_queued;
sched_info_reset_dequeued(t);
t->sched_info.run_delay += delta;
rq_sched_info_dequeued(task_rq(t), delta);
}
/*
......@@ -165,7 +187,7 @@ static void sched_info_arrive(struct task_struct *t)
if (t->sched_info.last_queued)
delta = now - t->sched_info.last_queued;
sched_info_dequeued(t);
sched_info_reset_dequeued(t);
t->sched_info.run_delay += delta;
t->sched_info.last_arrival = now;
t->sched_info.pcount++;
......@@ -243,6 +265,8 @@ sched_info_switch(struct task_struct *prev, struct task_struct *next)
}
#else
#define sched_info_queued(t) do { } while (0)
#define sched_info_reset_dequeued(t) do { } while (0)
#define sched_info_dequeued(t) do { } while (0)
#define sched_info_switch(t, next) do { } while (0)
#endif /* CONFIG_SCHEDSTATS || CONFIG_TASK_DELAY_ACCT */
kernel/sysctl.c
View file @ d14c8a68
......@@ -264,6 +264,14 @@ static struct ctl_table kern_table[] = {
.extra1 = &min_wakeup_granularity_ns,
.extra2 = &max_wakeup_granularity_ns,
},
{
.ctl_name = CTL_UNNUMBERED,
.procname = "sched_shares_ratelimit",
.data = &sysctl_sched_shares_ratelimit,
.maxlen = sizeof(unsigned int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = CTL_UNNUMBERED,
.procname = "sched_child_runs_first",
......
kernel/time/tick-sched.c
View file @ d14c8a68
......@@ -276,6 +276,7 @@ void tick_nohz_stop_sched_tick(void)
ts->tick_stopped = 1;
ts->idle_jiffies = last_jiffies;
rcu_enter_nohz();
sched_clock_tick_stop(cpu);
}
/*
......@@ -375,6 +376,7 @@ void tick_nohz_restart_sched_tick(void)
select_nohz_load_balancer(0);
now = ktime_get();
tick_do_update_jiffies64(now);
sched_clock_tick_start(cpu);
cpu_clear(cpu, nohz_cpu_mask);
/*
......
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