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Commit 774a694f authored by Linus Torvalds's avatar Linus Torvalds
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Merge branch 'sched-core-for-linus' of... 

Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (64 commits)
  sched: Fix sched::sched_stat_wait tracepoint field
  sched: Disable NEW_FAIR_SLEEPERS for now
  sched: Keep kthreads at default priority
  sched: Re-tune the scheduler latency defaults to decrease worst-case latencies
  sched: Turn off child_runs_first
  sched: Ensure that a child can't gain time over it's parent after fork()
  sched: enable SD_WAKE_IDLE
  sched: Deal with low-load in wake_affine()
  sched: Remove short cut from select_task_rq_fair()
  sched: Turn on SD_BALANCE_NEWIDLE
  sched: Clean up topology.h
  sched: Fix dynamic power-balancing crash
  sched: Remove reciprocal for cpu_power
  sched: Try to deal with low capacity, fix update_sd_power_savings_stats()
  sched: Try to deal with low capacity
  sched: Scale down cpu_power due to RT tasks
  sched: Implement dynamic cpu_power
  sched: Add smt_gain
  sched: Update the cpu_power sum during load-balance
  sched: Add SD_PREFER_SIBLING
  ...
parents 4f0ac854 e1f84508
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Showing with 1117 additions and 614 deletions
arch/x86/include/asm/topology.h
View file @ 774a694f
......@@ -129,25 +129,34 @@ extern unsigned long node_remap_size[];
#endif
/* sched_domains SD_NODE_INIT for NUMA machines */
#define SD_NODE_INIT (struct sched_domain) { \
.min_interval = 8, \
.max_interval = 32, \
.busy_factor = 32, \
.imbalance_pct = 125, \
.cache_nice_tries = SD_CACHE_NICE_TRIES, \
.busy_idx = 3, \
.idle_idx = SD_IDLE_IDX, \
.newidle_idx = SD_NEWIDLE_IDX, \
.wake_idx = 1, \
.forkexec_idx = SD_FORKEXEC_IDX, \
.flags = SD_LOAD_BALANCE \
| SD_BALANCE_EXEC \
| SD_BALANCE_FORK \
| SD_WAKE_AFFINE \
| SD_WAKE_BALANCE \
| SD_SERIALIZE, \
.last_balance = jiffies, \
.balance_interval = 1, \
#define SD_NODE_INIT (struct sched_domain) { \
.min_interval = 8, \
.max_interval = 32, \
.busy_factor = 32, \
.imbalance_pct = 125, \
.cache_nice_tries = SD_CACHE_NICE_TRIES, \
.busy_idx = 3, \
.idle_idx = SD_IDLE_IDX, \
.newidle_idx = SD_NEWIDLE_IDX, \
.wake_idx = 1, \
.forkexec_idx = SD_FORKEXEC_IDX, \
\
.flags = 1*SD_LOAD_BALANCE \
| 1*SD_BALANCE_NEWIDLE \
| 1*SD_BALANCE_EXEC \
| 1*SD_BALANCE_FORK \
| 0*SD_WAKE_IDLE \
| 1*SD_WAKE_AFFINE \
| 1*SD_WAKE_BALANCE \
| 0*SD_SHARE_CPUPOWER \
| 0*SD_POWERSAVINGS_BALANCE \
| 0*SD_SHARE_PKG_RESOURCES \
| 1*SD_SERIALIZE \
| 1*SD_WAKE_IDLE_FAR \
| 0*SD_PREFER_SIBLING \
, \
.last_balance = jiffies, \
.balance_interval = 1, \
}
#ifdef CONFIG_X86_64_ACPI_NUMA
......
fs/dcache.c
View file @ 774a694f
......@@ -32,6 +32,7 @@
#include <linux/swap.h>
#include <linux/bootmem.h>
#include <linux/fs_struct.h>
#include <linux/hardirq.h>
#include "internal.h"
int sysctl_vfs_cache_pressure __read_mostly = 100;
......
fs/locks.c
View file @ 774a694f
......@@ -768,7 +768,7 @@ static int flock_lock_file(struct file *filp, struct file_lock *request)
* give it the opportunity to lock the file.
*/
if (found)
cond_resched_bkl();
cond_resched();
find_conflict:
for_each_lock(inode, before) {
......
include/linux/hardirq.h
View file @ 774a694f
......@@ -64,6 +64,12 @@
#define HARDIRQ_OFFSET (1UL << HARDIRQ_SHIFT)
#define NMI_OFFSET (1UL << NMI_SHIFT)
#ifndef PREEMPT_ACTIVE
#define PREEMPT_ACTIVE_BITS 1
#define PREEMPT_ACTIVE_SHIFT (NMI_SHIFT + NMI_BITS)
#define PREEMPT_ACTIVE (__IRQ_MASK(PREEMPT_ACTIVE_BITS) << PREEMPT_ACTIVE_SHIFT)
#endif
#if PREEMPT_ACTIVE < (1 << (NMI_SHIFT + NMI_BITS))
#error PREEMPT_ACTIVE is too low!
#endif
......
include/linux/kernel.h
View file @ 774a694f
......@@ -125,7 +125,7 @@ extern int _cond_resched(void);
#endif
#ifdef CONFIG_DEBUG_SPINLOCK_SLEEP
void __might_sleep(char *file, int line);
void __might_sleep(char *file, int line, int preempt_offset);
/**
* might_sleep - annotation for functions that can sleep
*
......@@ -137,8 +137,9 @@ extern int _cond_resched(void);
* supposed to.
*/
# define might_sleep() \
do { __might_sleep(__FILE__, __LINE__); might_resched(); } while (0)
do { __might_sleep(__FILE__, __LINE__, 0); might_resched(); } while (0)
#else
static inline void __might_sleep(char *file, int line, int preempt_offset) { }
# define might_sleep() do { might_resched(); } while (0)
#endif
......
include/linux/sched.h
View file @ 774a694f
......@@ -38,6 +38,8 @@
#define SCHED_BATCH 3
/* SCHED_ISO: reserved but not implemented yet */
#define SCHED_IDLE 5
/* Can be ORed in to make sure the process is reverted back to SCHED_NORMAL on fork */
#define SCHED_RESET_ON_FORK 0x40000000
#ifdef __KERNEL__
......@@ -796,18 +798,19 @@ enum cpu_idle_type {
#define SCHED_LOAD_SCALE_FUZZ SCHED_LOAD_SCALE
#ifdef CONFIG_SMP
#define SD_LOAD_BALANCE 1 /* Do load balancing on this domain. */
#define SD_BALANCE_NEWIDLE 2 /* Balance when about to become idle */
#define SD_BALANCE_EXEC 4 /* Balance on exec */
#define SD_BALANCE_FORK 8 /* Balance on fork, clone */
#define SD_WAKE_IDLE 16 /* Wake to idle CPU on task wakeup */
#define SD_WAKE_AFFINE 32 /* Wake task to waking CPU */
#define SD_WAKE_BALANCE 64 /* Perform balancing at task wakeup */
#define SD_SHARE_CPUPOWER 128 /* Domain members share cpu power */
#define SD_POWERSAVINGS_BALANCE 256 /* Balance for power savings */
#define SD_SHARE_PKG_RESOURCES 512 /* Domain members share cpu pkg resources */
#define SD_SERIALIZE 1024 /* Only a single load balancing instance */
#define SD_WAKE_IDLE_FAR 2048 /* Gain latency sacrificing cache hit */
#define SD_LOAD_BALANCE 0x0001 /* Do load balancing on this domain. */
#define SD_BALANCE_NEWIDLE 0x0002 /* Balance when about to become idle */
#define SD_BALANCE_EXEC 0x0004 /* Balance on exec */
#define SD_BALANCE_FORK 0x0008 /* Balance on fork, clone */
#define SD_WAKE_IDLE 0x0010 /* Wake to idle CPU on task wakeup */
#define SD_WAKE_AFFINE 0x0020 /* Wake task to waking CPU */
#define SD_WAKE_BALANCE 0x0040 /* Perform balancing at task wakeup */
#define SD_SHARE_CPUPOWER 0x0080 /* Domain members share cpu power */
#define SD_POWERSAVINGS_BALANCE 0x0100 /* Balance for power savings */
#define SD_SHARE_PKG_RESOURCES 0x0200 /* Domain members share cpu pkg resources */
#define SD_SERIALIZE 0x0400 /* Only a single load balancing instance */
#define SD_WAKE_IDLE_FAR 0x0800 /* Gain latency sacrificing cache hit */
#define SD_PREFER_SIBLING 0x1000 /* Prefer to place tasks in a sibling domain */
enum powersavings_balance_level {
POWERSAVINGS_BALANCE_NONE = 0, /* No power saving load balance */
......@@ -827,7 +830,7 @@ static inline int sd_balance_for_mc_power(void)
if (sched_smt_power_savings)
return SD_POWERSAVINGS_BALANCE;
return 0;
return SD_PREFER_SIBLING;
}
static inline int sd_balance_for_package_power(void)
......@@ -835,7 +838,7 @@ static inline int sd_balance_for_package_power(void)
if (sched_mc_power_savings | sched_smt_power_savings)
return SD_POWERSAVINGS_BALANCE;
return 0;
return SD_PREFER_SIBLING;
}
/*
......@@ -857,15 +860,9 @@ struct sched_group {
/*
* CPU power of this group, SCHED_LOAD_SCALE being max power for a
* single CPU. This is read only (except for setup, hotplug CPU).
* Note : Never change cpu_power without recompute its reciprocal
*/
unsigned int __cpu_power;
/*
* reciprocal value of cpu_power to avoid expensive divides
* (see include/linux/reciprocal_div.h)
* single CPU.
*/
u32 reciprocal_cpu_power;
unsigned int cpu_power;
/*
* The CPUs this group covers.
......@@ -918,6 +915,7 @@ struct sched_domain {
unsigned int newidle_idx;
unsigned int wake_idx;
unsigned int forkexec_idx;
unsigned int smt_gain;
int flags; /* See SD_* */
enum sched_domain_level level;
......@@ -1045,7 +1043,6 @@ struct sched_class {
struct rq *busiest, struct sched_domain *sd,
enum cpu_idle_type idle);
void (*pre_schedule) (struct rq *this_rq, struct task_struct *task);
int (*needs_post_schedule) (struct rq *this_rq);
void (*post_schedule) (struct rq *this_rq);
void (*task_wake_up) (struct rq *this_rq, struct task_struct *task);
......@@ -1110,6 +1107,8 @@ struct sched_entity {
u64 wait_max;
u64 wait_count;
u64 wait_sum;
u64 iowait_count;
u64 iowait_sum;
u64 sleep_start;
u64 sleep_max;
......@@ -1234,11 +1233,19 @@ struct task_struct {
unsigned did_exec:1;
unsigned in_execve:1; /* Tell the LSMs that the process is doing an
* execve */
unsigned in_iowait:1;
/* Revert to default priority/policy when forking */
unsigned sched_reset_on_fork:1;
pid_t pid;
pid_t tgid;
#ifdef CONFIG_CC_STACKPROTECTOR
/* Canary value for the -fstack-protector gcc feature */
unsigned long stack_canary;
#endif
/*
* pointers to (original) parent process, youngest child, younger sibling,
......@@ -1840,11 +1847,12 @@ extern unsigned int sysctl_sched_min_granularity;
extern unsigned int sysctl_sched_wakeup_granularity;
extern unsigned int sysctl_sched_shares_ratelimit;
extern unsigned int sysctl_sched_shares_thresh;
#ifdef CONFIG_SCHED_DEBUG
extern unsigned int sysctl_sched_child_runs_first;
#ifdef CONFIG_SCHED_DEBUG
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_time_avg;
extern unsigned int sysctl_timer_migration;
int sched_nr_latency_handler(struct ctl_table *table, int write,
......@@ -2308,23 +2316,31 @@ static inline int need_resched(void)
* cond_resched_softirq() will enable bhs before scheduling.
*/
extern int _cond_resched(void);
#ifdef CONFIG_PREEMPT_BKL
static inline int cond_resched(void)
{
return 0;
}
#define cond_resched() ({ \
__might_sleep(__FILE__, __LINE__, 0); \
_cond_resched(); \
})
extern int __cond_resched_lock(spinlock_t *lock);
#ifdef CONFIG_PREEMPT
#define PREEMPT_LOCK_OFFSET PREEMPT_OFFSET
#else
static inline int cond_resched(void)
{
return _cond_resched();
}
#define PREEMPT_LOCK_OFFSET 0
#endif
extern int cond_resched_lock(spinlock_t * lock);
extern int cond_resched_softirq(void);
static inline int cond_resched_bkl(void)
{
return _cond_resched();
}
#define cond_resched_lock(lock) ({ \
__might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET); \
__cond_resched_lock(lock); \
})
extern int __cond_resched_softirq(void);
#define cond_resched_softirq() ({ \
__might_sleep(__FILE__, __LINE__, SOFTIRQ_OFFSET); \
__cond_resched_softirq(); \
})
/*
* Does a critical section need to be broken due to another
......
include/linux/topology.h
View file @ 774a694f
......@@ -85,20 +85,29 @@ int arch_update_cpu_topology(void);
#define ARCH_HAS_SCHED_WAKE_IDLE
/* Common values for SMT siblings */
#ifndef SD_SIBLING_INIT
#define SD_SIBLING_INIT (struct sched_domain) { \
.min_interval = 1, \
.max_interval = 2, \
.busy_factor = 64, \
.imbalance_pct = 110, \
.flags = SD_LOAD_BALANCE \
| SD_BALANCE_NEWIDLE \
| SD_BALANCE_FORK \
| SD_BALANCE_EXEC \
| SD_WAKE_AFFINE \
| SD_WAKE_BALANCE \
| SD_SHARE_CPUPOWER, \
.last_balance = jiffies, \
.balance_interval = 1, \
#define SD_SIBLING_INIT (struct sched_domain) { \
.min_interval = 1, \
.max_interval = 2, \
.busy_factor = 64, \
.imbalance_pct = 110, \
\
.flags = 1*SD_LOAD_BALANCE \
| 1*SD_BALANCE_NEWIDLE \
| 1*SD_BALANCE_EXEC \
| 1*SD_BALANCE_FORK \
| 0*SD_WAKE_IDLE \
| 1*SD_WAKE_AFFINE \
| 1*SD_WAKE_BALANCE \
| 1*SD_SHARE_CPUPOWER \
| 0*SD_POWERSAVINGS_BALANCE \
| 0*SD_SHARE_PKG_RESOURCES \
| 0*SD_SERIALIZE \
| 0*SD_WAKE_IDLE_FAR \
| 0*SD_PREFER_SIBLING \
, \
.last_balance = jiffies, \
.balance_interval = 1, \
.smt_gain = 1178, /* 15% */ \
}
#endif
#endif /* CONFIG_SCHED_SMT */
......@@ -106,69 +115,94 @@ int arch_update_cpu_topology(void);
#ifdef CONFIG_SCHED_MC
/* Common values for MC siblings. for now mostly derived from SD_CPU_INIT */
#ifndef SD_MC_INIT
#define SD_MC_INIT (struct sched_domain) { \
.min_interval = 1, \
.max_interval = 4, \
.busy_factor = 64, \
.imbalance_pct = 125, \
.cache_nice_tries = 1, \
.busy_idx = 2, \
.wake_idx = 1, \
.forkexec_idx = 1, \
.flags = SD_LOAD_BALANCE \
| SD_BALANCE_FORK \
| SD_BALANCE_EXEC \
| SD_WAKE_AFFINE \
| SD_WAKE_BALANCE \
| SD_SHARE_PKG_RESOURCES\
| sd_balance_for_mc_power()\
| sd_power_saving_flags(),\
.last_balance = jiffies, \
.balance_interval = 1, \
#define SD_MC_INIT (struct sched_domain) { \
.min_interval = 1, \
.max_interval = 4, \
.busy_factor = 64, \
.imbalance_pct = 125, \
.cache_nice_tries = 1, \
.busy_idx = 2, \
.wake_idx = 1, \
.forkexec_idx = 1, \
\
.flags = 1*SD_LOAD_BALANCE \
| 1*SD_BALANCE_NEWIDLE \
| 1*SD_BALANCE_EXEC \
| 1*SD_BALANCE_FORK \
| 1*SD_WAKE_IDLE \
| 1*SD_WAKE_AFFINE \
| 1*SD_WAKE_BALANCE \
| 0*SD_SHARE_CPUPOWER \
| 1*SD_SHARE_PKG_RESOURCES \
| 0*SD_SERIALIZE \
| 0*SD_WAKE_IDLE_FAR \
| sd_balance_for_mc_power() \
| sd_power_saving_flags() \
, \
.last_balance = jiffies, \
.balance_interval = 1, \
}
#endif
#endif /* CONFIG_SCHED_MC */
/* Common values for CPUs */
#ifndef SD_CPU_INIT
#define SD_CPU_INIT (struct sched_domain) { \
.min_interval = 1, \
.max_interval = 4, \
.busy_factor = 64, \
.imbalance_pct = 125, \
.cache_nice_tries = 1, \
.busy_idx = 2, \
.idle_idx = 1, \
.newidle_idx = 2, \
.wake_idx = 1, \
.forkexec_idx = 1, \
.flags = SD_LOAD_BALANCE \
| SD_BALANCE_EXEC \
| SD_BALANCE_FORK \
| SD_WAKE_AFFINE \
| SD_WAKE_BALANCE \
| sd_balance_for_package_power()\
| sd_power_saving_flags(),\
.last_balance = jiffies, \
.balance_interval = 1, \
#define SD_CPU_INIT (struct sched_domain) { \
.min_interval = 1, \
.max_interval = 4, \
.busy_factor = 64, \
.imbalance_pct = 125, \
.cache_nice_tries = 1, \
.busy_idx = 2, \
.idle_idx = 1, \
.newidle_idx = 2, \
.wake_idx = 1, \
.forkexec_idx = 1, \
\
.flags = 1*SD_LOAD_BALANCE \
| 1*SD_BALANCE_NEWIDLE \
| 1*SD_BALANCE_EXEC \
| 1*SD_BALANCE_FORK \
| 1*SD_WAKE_IDLE \
| 0*SD_WAKE_AFFINE \
| 1*SD_WAKE_BALANCE \
| 0*SD_SHARE_CPUPOWER \
| 0*SD_SHARE_PKG_RESOURCES \
| 0*SD_SERIALIZE \
| 0*SD_WAKE_IDLE_FAR \
| sd_balance_for_package_power() \
| sd_power_saving_flags() \
, \
.last_balance = jiffies, \
.balance_interval = 1, \
}
#endif
/* sched_domains SD_ALLNODES_INIT for NUMA machines */
#define SD_ALLNODES_INIT (struct sched_domain) { \
.min_interval = 64, \
.max_interval = 64*num_online_cpus(), \
.busy_factor = 128, \
.imbalance_pct = 133, \
.cache_nice_tries = 1, \
.busy_idx = 3, \
.idle_idx = 3, \
.flags = SD_LOAD_BALANCE \
| SD_BALANCE_NEWIDLE \
| SD_WAKE_AFFINE \
| SD_SERIALIZE, \
.last_balance = jiffies, \
.balance_interval = 64, \
#define SD_ALLNODES_INIT (struct sched_domain) { \
.min_interval = 64, \
.max_interval = 64*num_online_cpus(), \
.busy_factor = 128, \
.imbalance_pct = 133, \
.cache_nice_tries = 1, \
.busy_idx = 3, \
.idle_idx = 3, \
.flags = 1*SD_LOAD_BALANCE \
| 1*SD_BALANCE_NEWIDLE \
| 0*SD_BALANCE_EXEC \
| 0*SD_BALANCE_FORK \
| 0*SD_WAKE_IDLE \
| 1*SD_WAKE_AFFINE \
| 0*SD_WAKE_BALANCE \
| 0*SD_SHARE_CPUPOWER \
| 0*SD_POWERSAVINGS_BALANCE \
| 0*SD_SHARE_PKG_RESOURCES \
| 1*SD_SERIALIZE \
| 1*SD_WAKE_IDLE_FAR \
| 0*SD_PREFER_SIBLING \
, \
.last_balance = jiffies, \
.balance_interval = 64, \
}
#ifdef CONFIG_NUMA
......
include/trace/events/sched.h
View file @ 774a694f
......@@ -340,6 +340,101 @@ TRACE_EVENT(sched_signal_send,
__entry->sig, __entry->comm, __entry->pid)
);
/*
* XXX the below sched_stat tracepoints only apply to SCHED_OTHER/BATCH/IDLE
* adding sched_stat support to SCHED_FIFO/RR would be welcome.
*/
/*
* Tracepoint for accounting wait time (time the task is runnable
* but not actually running due to scheduler contention).
*/
TRACE_EVENT(sched_stat_wait,
TP_PROTO(struct task_struct *tsk, u64 delay),
TP_ARGS(tsk, delay),
TP_STRUCT__entry(
__array( char, comm, TASK_COMM_LEN )
__field( pid_t, pid )
__field( u64, delay )
),
TP_fast_assign(
memcpy(__entry->comm, tsk->comm, TASK_COMM_LEN);
__entry->pid = tsk->pid;
__entry->delay = delay;
)
TP_perf_assign(
__perf_count(delay);
),
TP_printk("task: %s:%d wait: %Lu [ns]",
__entry->comm, __entry->pid,
(unsigned long long)__entry->delay)
);
/*
* Tracepoint for accounting sleep time (time the task is not runnable,
* including iowait, see below).
*/
TRACE_EVENT(sched_stat_sleep,
TP_PROTO(struct task_struct *tsk, u64 delay),
TP_ARGS(tsk, delay),
TP_STRUCT__entry(
__array( char, comm, TASK_COMM_LEN )
__field( pid_t, pid )
__field( u64, delay )
),
TP_fast_assign(
memcpy(__entry->comm, tsk->comm, TASK_COMM_LEN);
__entry->pid = tsk->pid;
__entry->delay = delay;
)
TP_perf_assign(
__perf_count(delay);
),
TP_printk("task: %s:%d sleep: %Lu [ns]",
__entry->comm, __entry->pid,
(unsigned long long)__entry->delay)
);
/*
* Tracepoint for accounting iowait time (time the task is not runnable
* due to waiting on IO to complete).
*/
TRACE_EVENT(sched_stat_iowait,
TP_PROTO(struct task_struct *tsk, u64 delay),
TP_ARGS(tsk, delay),
TP_STRUCT__entry(
__array( char, comm, TASK_COMM_LEN )
__field( pid_t, pid )
__field( u64, delay )
),
TP_fast_assign(
memcpy(__entry->comm, tsk->comm, TASK_COMM_LEN);
__entry->pid = tsk->pid;
__entry->delay = delay;
)
TP_perf_assign(
__perf_count(delay);
),
TP_printk("task: %s:%d iowait: %Lu [ns]",
__entry->comm, __entry->pid,
(unsigned long long)__entry->delay)
);
#endif /* _TRACE_SCHED_H */
/* This part must be outside protection */
......
init/main.c
View file @ 774a694f
......@@ -631,7 +631,6 @@ asmlinkage void __init start_kernel(void)
softirq_init();
timekeeping_init();
time_init();
sched_clock_init();
profile_init();
if (!irqs_disabled())
printk(KERN_CRIT "start_kernel(): bug: interrupts were "
......@@ -682,6 +681,7 @@ asmlinkage void __init start_kernel(void)
numa_policy_init();
if (late_time_init)
late_time_init();
sched_clock_init();
calibrate_delay();
pidmap_init();
anon_vma_init();
......
kernel/kthread.c
View file @ 774a694f
......@@ -16,8 +16,6 @@
#include <linux/mutex.h>
#include <trace/events/sched.h>
#define KTHREAD_NICE_LEVEL (-5)
static DEFINE_SPINLOCK(kthread_create_lock);
static LIST_HEAD(kthread_create_list);
struct task_struct *kthreadd_task;
......@@ -145,7 +143,6 @@ struct task_struct *kthread_create(int (*threadfn)(void *data),
* The kernel thread should not inherit these properties.
*/
sched_setscheduler_nocheck(create.result, SCHED_NORMAL, &param);
set_user_nice(create.result, KTHREAD_NICE_LEVEL);
set_cpus_allowed_ptr(create.result, cpu_all_mask);
}
return create.result;
......@@ -221,7 +218,6 @@ int kthreadd(void *unused)
/* Setup a clean context for our children to inherit. */
set_task_comm(tsk, "kthreadd");
ignore_signals(tsk);
set_user_nice(tsk, KTHREAD_NICE_LEVEL);
set_cpus_allowed_ptr(tsk, cpu_all_mask);
set_mems_allowed(node_possible_map);
......
kernel/sched.c
View file @ 774a694f
This diff is collapsed.
kernel/sched_cpupri.c
View file @ 774a694f
......@@ -127,21 +127,11 @@ void cpupri_set(struct cpupri *cp, int cpu, int newpri)
/*
* If the cpu was currently mapped to a different value, we
* first need to unmap the old value
* need to map it to the new value then remove the old value.
* Note, we must add the new value first, otherwise we risk the
* cpu being cleared from pri_active, and this cpu could be
* missed for a push or pull.
*/
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);
cpumask_clear_cpu(cpu, vec->mask);
spin_unlock_irqrestore(&vec->lock, flags);
}
if (likely(newpri != CPUPRI_INVALID)) {
struct cpupri_vec *vec = &cp->pri_to_cpu[newpri];
......@@ -154,6 +144,18 @@ void cpupri_set(struct cpupri *cp, int cpu, int newpri)
spin_unlock_irqrestore(&vec->lock, flags);
}
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);
cpumask_clear_cpu(cpu, vec->mask);
spin_unlock_irqrestore(&vec->lock, flags);
}
*currpri = newpri;
}
......
kernel/sched_debug.c
View file @ 774a694f
......@@ -409,6 +409,8 @@ void proc_sched_show_task(struct task_struct *p, struct seq_file *m)
PN(se.wait_max);
PN(se.wait_sum);
P(se.wait_count);
PN(se.iowait_sum);
P(se.iowait_count);
P(sched_info.bkl_count);
P(se.nr_migrations);
P(se.nr_migrations_cold);
......@@ -479,6 +481,8 @@ void proc_sched_set_task(struct task_struct *p)
p->se.wait_max = 0;
p->se.wait_sum = 0;
p->se.wait_count = 0;
p->se.iowait_sum = 0;
p->se.iowait_count = 0;
p->se.sleep_max = 0;
p->se.sum_sleep_runtime = 0;
p->se.block_max = 0;
......
kernel/sched_fair.c
View file @ 774a694f
......@@ -24,7 +24,7 @@
/*
* Targeted preemption latency for CPU-bound tasks:
* (default: 20ms * (1 + ilog(ncpus)), units: nanoseconds)
* (default: 5ms * (1 + ilog(ncpus)), units: nanoseconds)
*
* NOTE: this latency value is not the same as the concept of
* 'timeslice length' - timeslices in CFS are of variable length
......@@ -34,13 +34,13 @@
* (to see the precise effective timeslice length of your workload,
* run vmstat and monitor the context-switches (cs) field)
*/
unsigned int sysctl_sched_latency = 20000000ULL;
unsigned int sysctl_sched_latency = 5000000ULL;
/*
* Minimal preemption granularity for CPU-bound tasks:
* (default: 4 msec * (1 + ilog(ncpus)), units: nanoseconds)
* (default: 1 msec * (1 + ilog(ncpus)), units: nanoseconds)
*/
unsigned int sysctl_sched_min_granularity = 4000000ULL;
unsigned int sysctl_sched_min_granularity = 1000000ULL;
/*
* is kept at sysctl_sched_latency / sysctl_sched_min_granularity
......@@ -48,10 +48,10 @@ unsigned int sysctl_sched_min_granularity = 4000000ULL;
static unsigned int sched_nr_latency = 5;
/*
* After fork, child runs first. (default) If set to 0 then
* After fork, child runs first. If set to 0 (default) then
* parent will (try to) run first.
*/
const_debug unsigned int sysctl_sched_child_runs_first = 1;
unsigned int sysctl_sched_child_runs_first __read_mostly;
/*
* sys_sched_yield() compat mode
......@@ -63,13 +63,13 @@ unsigned int __read_mostly sysctl_sched_compat_yield;
/*
* SCHED_OTHER wake-up granularity.
* (default: 5 msec * (1 + ilog(ncpus)), units: nanoseconds)
* (default: 1 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 = 5000000UL;
unsigned int sysctl_sched_wakeup_granularity = 1000000UL;
const_debug unsigned int sysctl_sched_migration_cost = 500000UL;
......@@ -79,11 +79,6 @@ static const struct sched_class fair_sched_class;
* CFS operations on generic schedulable entities:
*/
static inline struct task_struct *task_of(struct sched_entity *se)
{
return container_of(se, struct task_struct, se);
}
#ifdef CONFIG_FAIR_GROUP_SCHED
/* cpu runqueue to which this cfs_rq is attached */
......@@ -95,6 +90,14 @@ static inline struct rq *rq_of(struct cfs_rq *cfs_rq)
/* An entity is a task if it doesn't "own" a runqueue */
#define entity_is_task(se) (!se->my_q)
static inline struct task_struct *task_of(struct sched_entity *se)
{
#ifdef CONFIG_SCHED_DEBUG
WARN_ON_ONCE(!entity_is_task(se));
#endif
return container_of(se, struct task_struct, se);
}
/* Walk up scheduling entities hierarchy */
#define for_each_sched_entity(se) \
for (; se; se = se->parent)
......@@ -186,7 +189,12 @@ find_matching_se(struct sched_entity **se, struct sched_entity **pse)
}
}
#else /* CONFIG_FAIR_GROUP_SCHED */
#else /* !CONFIG_FAIR_GROUP_SCHED */
static inline struct task_struct *task_of(struct sched_entity *se)
{
return container_of(se, struct task_struct, se);
}
static inline struct rq *rq_of(struct cfs_rq *cfs_rq)
{
......@@ -537,6 +545,12 @@ update_stats_wait_end(struct cfs_rq *cfs_rq, struct sched_entity *se)
schedstat_set(se->wait_count, se->wait_count + 1);
schedstat_set(se->wait_sum, se->wait_sum +
rq_of(cfs_rq)->clock - se->wait_start);
#ifdef CONFIG_SCHEDSTATS
if (entity_is_task(se)) {
trace_sched_stat_wait(task_of(se),
rq_of(cfs_rq)->clock - se->wait_start);
}
#endif
schedstat_set(se->wait_start, 0);
}
......@@ -628,8 +642,10 @@ static void enqueue_sleeper(struct cfs_rq *cfs_rq, struct sched_entity *se)
se->sleep_start = 0;
se->sum_sleep_runtime += delta;
if (tsk)
if (tsk) {
account_scheduler_latency(tsk, delta >> 10, 1);
trace_sched_stat_sleep(tsk, delta);
}
}
if (se->block_start) {
u64 delta = rq_of(cfs_rq)->clock - se->block_start;
......@@ -644,6 +660,12 @@ static void enqueue_sleeper(struct cfs_rq *cfs_rq, struct sched_entity *se)
se->sum_sleep_runtime += delta;
if (tsk) {
if (tsk->in_iowait) {
se->iowait_sum += delta;
se->iowait_count++;
trace_sched_stat_iowait(tsk, delta);
}
/*
* Blocking time is in units of nanosecs, so shift by
* 20 to get a milliseconds-range estimation of the
......@@ -705,11 +727,11 @@ place_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int initial)
vruntime -= thresh;
}
/* ensure we never gain time by being placed backwards. */
vruntime = max_vruntime(se->vruntime, vruntime);
}
/* ensure we never gain time by being placed backwards. */
vruntime = max_vruntime(se->vruntime, vruntime);
se->vruntime = vruntime;
}
......@@ -1046,17 +1068,21 @@ static void yield_task_fair(struct rq *rq)
* search starts with cpus closest then further out as needed,
* so we always favor a closer, idle cpu.
* Domains may include CPUs that are not usable for migration,
* hence we need to mask them out (cpu_active_mask)
* hence we need to mask them out (rq->rd->online)
*
* Returns the CPU we should wake onto.
*/
#if defined(ARCH_HAS_SCHED_WAKE_IDLE)
#define cpu_rd_active(cpu, rq) cpumask_test_cpu(cpu, rq->rd->online)
static int wake_idle(int cpu, struct task_struct *p)
{
struct sched_domain *sd;
int i;
unsigned int chosen_wakeup_cpu;
int this_cpu;
struct rq *task_rq = task_rq(p);
/*
* At POWERSAVINGS_BALANCE_WAKEUP level, if both this_cpu and prev_cpu
......@@ -1089,10 +1115,10 @@ static int wake_idle(int cpu, struct task_struct *p)
for_each_domain(cpu, sd) {
if ((sd->flags & SD_WAKE_IDLE)
|| ((sd->flags & SD_WAKE_IDLE_FAR)
&& !task_hot(p, task_rq(p)->clock, sd))) {
&& !task_hot(p, task_rq->clock, sd))) {
for_each_cpu_and(i, sched_domain_span(sd),
&p->cpus_allowed) {
if (cpu_active(i) && idle_cpu(i)) {
if (cpu_rd_active(i, task_rq) && idle_cpu(i)) {
if (i != task_cpu(p)) {
schedstat_inc(p,
se.nr_wakeups_idle);
......@@ -1235,7 +1261,17 @@ wake_affine(struct sched_domain *this_sd, struct rq *this_rq,
tg = task_group(p);
weight = p->se.load.weight;
balanced = 100*(tl + effective_load(tg, this_cpu, weight, weight)) <=
/*
* In low-load situations, where prev_cpu is idle and this_cpu is idle
* due to the sync cause above having dropped tl to 0, we'll always have
* an imbalance, but there's really nothing you can do about that, so
* that's good too.
*
* Otherwise check if either cpus are near enough in load to allow this
* task to be woken on this_cpu.
*/
balanced = !tl ||
100*(tl + effective_load(tg, this_cpu, weight, weight)) <=
imbalance*(load + effective_load(tg, prev_cpu, 0, weight));
/*
......@@ -1278,8 +1314,6 @@ static int select_task_rq_fair(struct task_struct *p, int sync)
this_rq = cpu_rq(this_cpu);
new_cpu = prev_cpu;
if (prev_cpu == this_cpu)
goto out;
/*
* 'this_sd' is the first domain that both
* this_cpu and prev_cpu are present in:
......@@ -1721,6 +1755,8 @@ static void task_new_fair(struct rq *rq, struct task_struct *p)
sched_info_queued(p);
update_curr(cfs_rq);
if (curr)
se->vruntime = curr->vruntime;
place_entity(cfs_rq, se, 1);
/* 'curr' will be NULL if the child belongs to a different group */
......
kernel/sched_features.h
View file @ 774a694f
SCHED_FEAT(NEW_FAIR_SLEEPERS, 1)
SCHED_FEAT(NEW_FAIR_SLEEPERS, 0)
SCHED_FEAT(NORMALIZED_SLEEPER, 0)
SCHED_FEAT(ADAPTIVE_GRAN, 1)
SCHED_FEAT(WAKEUP_PREEMPT, 1)
......
kernel/sched_rt.c
View file @ 774a694f
......@@ -3,15 +3,18 @@
* policies)
*/
#ifdef CONFIG_RT_GROUP_SCHED
#define rt_entity_is_task(rt_se) (!(rt_se)->my_q)
static inline struct task_struct *rt_task_of(struct sched_rt_entity *rt_se)
{
#ifdef CONFIG_SCHED_DEBUG
WARN_ON_ONCE(!rt_entity_is_task(rt_se));
#endif
return container_of(rt_se, struct task_struct, rt);
}
#ifdef CONFIG_RT_GROUP_SCHED
#define rt_entity_is_task(rt_se) (!(rt_se)->my_q)
static inline struct rq *rq_of_rt_rq(struct rt_rq *rt_rq)
{
return rt_rq->rq;
......@@ -26,6 +29,11 @@ static inline struct rt_rq *rt_rq_of_se(struct sched_rt_entity *rt_se)
#define rt_entity_is_task(rt_se) (1)
static inline struct task_struct *rt_task_of(struct sched_rt_entity *rt_se)
{
return container_of(rt_se, struct task_struct, rt);
}
static inline struct rq *rq_of_rt_rq(struct rt_rq *rt_rq)
{
return container_of(rt_rq, struct rq, rt);
......@@ -128,6 +136,11 @@ static void dequeue_pushable_task(struct rq *rq, struct task_struct *p)
plist_del(&p->pushable_tasks, &rq->rt.pushable_tasks);
}
static inline int has_pushable_tasks(struct rq *rq)
{
return !plist_head_empty(&rq->rt.pushable_tasks);
}
#else
static inline void enqueue_pushable_task(struct rq *rq, struct task_struct *p)
......@@ -602,6 +615,8 @@ static void update_curr_rt(struct rq *rq)
curr->se.exec_start = rq->clock;
cpuacct_charge(curr, delta_exec);
sched_rt_avg_update(rq, delta_exec);
if (!rt_bandwidth_enabled())
return;
......@@ -874,8 +889,6 @@ static void enqueue_task_rt(struct rq *rq, struct task_struct *p, int wakeup)
if (!task_current(rq, p) && p->rt.nr_cpus_allowed > 1)
enqueue_pushable_task(rq, p);
inc_cpu_load(rq, p->se.load.weight);
}
static void dequeue_task_rt(struct rq *rq, struct task_struct *p, int sleep)
......@@ -886,8 +899,6 @@ static void dequeue_task_rt(struct rq *rq, struct task_struct *p, int sleep)
dequeue_rt_entity(rt_se);
dequeue_pushable_task(rq, p);
dec_cpu_load(rq, p->se.load.weight);
}
/*
......@@ -1064,6 +1075,14 @@ static struct task_struct *pick_next_task_rt(struct rq *rq)
if (p)
dequeue_pushable_task(rq, p);
#ifdef CONFIG_SMP
/*
* We detect this state here so that we can avoid taking the RQ
* lock again later if there is no need to push
*/
rq->post_schedule = has_pushable_tasks(rq);
#endif
return p;
}
......@@ -1161,13 +1180,6 @@ static int find_lowest_rq(struct task_struct *task)
if (!cpupri_find(&task_rq(task)->rd->cpupri, task, lowest_mask))
return -1; /* No targets found */
/*
* Only consider CPUs that are usable for migration.
* I guess we might want to change cpupri_find() to ignore those
* in the first place.
*/
cpumask_and(lowest_mask, lowest_mask, cpu_active_mask);
/*
* At this point we have built a mask of cpus representing the
* lowest priority tasks in the system. Now we want to elect
......@@ -1262,11 +1274,6 @@ static struct rq *find_lock_lowest_rq(struct task_struct *task, struct rq *rq)
return lowest_rq;
}
static inline int has_pushable_tasks(struct rq *rq)
{
return !plist_head_empty(&rq->rt.pushable_tasks);
}
static struct task_struct *pick_next_pushable_task(struct rq *rq)
{
struct task_struct *p;
......@@ -1466,23 +1473,9 @@ static void pre_schedule_rt(struct rq *rq, struct task_struct *prev)
pull_rt_task(rq);
}
/*
* assumes rq->lock is held
*/
static int needs_post_schedule_rt(struct rq *rq)
{
return has_pushable_tasks(rq);
}
static void post_schedule_rt(struct rq *rq)
{
/*
* This is only called if needs_post_schedule_rt() indicates that
* we need to push tasks away
*/
spin_lock_irq(&rq->lock);
push_rt_tasks(rq);
spin_unlock_irq(&rq->lock);
}
/*
......@@ -1758,7 +1751,6 @@ static const struct sched_class rt_sched_class = {
.rq_online = rq_online_rt,
.rq_offline = rq_offline_rt,
.pre_schedule = pre_schedule_rt,
.needs_post_schedule = needs_post_schedule_rt,
.post_schedule = post_schedule_rt,
.task_wake_up = task_wake_up_rt,
.switched_from = switched_from_rt,
......
kernel/sysctl.c
View file @ 774a694f
......@@ -245,6 +245,14 @@ static int max_wakeup_granularity_ns = NSEC_PER_SEC; /* 1 second */
#endif
static struct ctl_table kern_table[] = {
{
.ctl_name = CTL_UNNUMBERED,
.procname = "sched_child_runs_first",
.data = &sysctl_sched_child_runs_first,
.maxlen = sizeof(unsigned int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
#ifdef CONFIG_SCHED_DEBUG
{
.ctl_name = CTL_UNNUMBERED,
......@@ -297,14 +305,6 @@ static struct ctl_table kern_table[] = {
.strategy = &sysctl_intvec,
.extra1 = &zero,
},
{
.ctl_name = CTL_UNNUMBERED,
.procname = "sched_child_runs_first",
.data = &sysctl_sched_child_runs_first,
.maxlen = sizeof(unsigned int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = CTL_UNNUMBERED,
.procname = "sched_features",
......@@ -329,6 +329,14 @@ static struct ctl_table kern_table[] = {
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = CTL_UNNUMBERED,
.procname = "sched_time_avg",
.data = &sysctl_sched_time_avg,
.maxlen = sizeof(unsigned int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{
.ctl_name = CTL_UNNUMBERED,
.procname = "timer_migration",
......
kernel/workqueue.c
View file @ 774a694f
......@@ -317,8 +317,6 @@ static int worker_thread(void *__cwq)
if (cwq->wq->freezeable)
set_freezable();
set_user_nice(current, -5);
for (;;) {
prepare_to_wait(&cwq->more_work, &wait, TASK_INTERRUPTIBLE);
if (!freezing(current) &&
......
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