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authorLinus Torvalds <torvalds@linux-foundation.org>2011-07-22 16:45:02 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2011-07-22 16:45:02 -0700
commitbdc7ccfc0631797636837b10df7f87bc1e2e4ae3 (patch)
tree70f09f8ffee07486d41ca254b8abb05692713d1e /kernel/sched.c
parent4d4abdcb1dee03a4f9d6d2021622ed07e14dfd17 (diff)
parent0f3171438fc917b9f6b8b60dbb7a3fff9a0f68fd (diff)
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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: (24 commits) sched: Cleanup duplicate local variable in [enqueue|dequeue]_task_fair sched: Replace use of entity_key() sched: Separate group-scheduling code more clearly sched: Reorder root_domain to remove 64 bit alignment padding sched: Do not attempt to destroy uninitialized rt_bandwidth sched: Remove unused function cpu_cfs_rq() sched: Fix (harmless) typo 'CONFG_FAIR_GROUP_SCHED' sched, cgroup: Optimize load_balance_fair() sched: Don't update shares twice on on_rq parent sched: update correct entity's runtime in check_preempt_wakeup() xtensa: Use generic config PREEMPT definition h8300: Use generic config PREEMPT definition m32r: Use generic PREEMPT config sched: Skip autogroup when looking for all rt sched groups sched: Simplify mutex_spin_on_owner() sched: Remove rcu_read_lock() from wake_affine() sched: Generalize sleep inside spinlock detection sched: Make sleeping inside spinlock detection working in !CONFIG_PREEMPT sched: Isolate preempt counting in its own config option sched: Remove pointless in_atomic() definition check ...
Diffstat (limited to 'kernel/sched.c')
-rw-r--r--kernel/sched.c117
1 files changed, 36 insertions, 81 deletions
diff --git a/kernel/sched.c b/kernel/sched.c
index 84b9e076812e..9aaf567c5da5 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -124,7 +124,7 @@
static inline int rt_policy(int policy)
{
- if (unlikely(policy == SCHED_FIFO || policy == SCHED_RR))
+ if (policy == SCHED_FIFO || policy == SCHED_RR)
return 1;
return 0;
}
@@ -422,6 +422,7 @@ struct rt_rq {
*/
struct root_domain {
atomic_t refcount;
+ atomic_t rto_count;
struct rcu_head rcu;
cpumask_var_t span;
cpumask_var_t online;
@@ -431,7 +432,6 @@ struct root_domain {
* one runnable RT task.
*/
cpumask_var_t rto_mask;
- atomic_t rto_count;
struct cpupri cpupri;
};
@@ -1568,38 +1568,6 @@ static unsigned long cpu_avg_load_per_task(int cpu)
return rq->avg_load_per_task;
}
-#ifdef CONFIG_FAIR_GROUP_SCHED
-
-/*
- * 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 int tg_load_down(struct task_group *tg, void *data)
-{
- unsigned long load;
- long cpu = (long)data;
-
- if (!tg->parent) {
- load = cpu_rq(cpu)->load.weight;
- } else {
- load = tg->parent->cfs_rq[cpu]->h_load;
- load *= tg->se[cpu]->load.weight;
- load /= tg->parent->cfs_rq[cpu]->load.weight + 1;
- }
-
- tg->cfs_rq[cpu]->h_load = load;
-
- return 0;
-}
-
-static void update_h_load(long cpu)
-{
- walk_tg_tree(tg_load_down, tg_nop, (void *)cpu);
-}
-
-#endif
-
#ifdef CONFIG_PREEMPT
static void double_rq_lock(struct rq *rq1, struct rq *rq2);
@@ -2497,7 +2465,7 @@ ttwu_do_wakeup(struct rq *rq, struct task_struct *p, int wake_flags)
if (p->sched_class->task_woken)
p->sched_class->task_woken(rq, p);
- if (unlikely(rq->idle_stamp)) {
+ if (rq->idle_stamp) {
u64 delta = rq->clock - rq->idle_stamp;
u64 max = 2*sysctl_sched_migration_cost;
@@ -2886,7 +2854,7 @@ void sched_fork(struct task_struct *p)
#if defined(CONFIG_SMP)
p->on_cpu = 0;
#endif
-#ifdef CONFIG_PREEMPT
+#ifdef CONFIG_PREEMPT_COUNT
/* Want to start with kernel preemption disabled. */
task_thread_info(p)->preempt_count = 1;
#endif
@@ -4338,11 +4306,8 @@ EXPORT_SYMBOL(schedule);
static inline bool owner_running(struct mutex *lock, struct task_struct *owner)
{
- bool ret = false;
-
- rcu_read_lock();
if (lock->owner != owner)
- goto fail;
+ return false;
/*
* Ensure we emit the owner->on_cpu, dereference _after_ checking
@@ -4352,11 +4317,7 @@ static inline bool owner_running(struct mutex *lock, struct task_struct *owner)
*/
barrier();
- ret = owner->on_cpu;
-fail:
- rcu_read_unlock();
-
- return ret;
+ return owner->on_cpu;
}
/*
@@ -4368,21 +4329,21 @@ int mutex_spin_on_owner(struct mutex *lock, struct task_struct *owner)
if (!sched_feat(OWNER_SPIN))
return 0;
+ rcu_read_lock();
while (owner_running(lock, owner)) {
if (need_resched())
- return 0;
+ break;
arch_mutex_cpu_relax();
}
+ rcu_read_unlock();
/*
- * If the owner changed to another task there is likely
- * heavy contention, stop spinning.
+ * We break out the loop above on need_resched() and when the
+ * owner changed, which is a sign for heavy contention. Return
+ * success only when lock->owner is NULL.
*/
- if (lock->owner)
- return 0;
-
- return 1;
+ return lock->owner == NULL;
}
#endif
@@ -7898,17 +7859,10 @@ int in_sched_functions(unsigned long addr)
&& addr < (unsigned long)__sched_text_end);
}
-static void init_cfs_rq(struct cfs_rq *cfs_rq, struct rq *rq)
+static void init_cfs_rq(struct cfs_rq *cfs_rq)
{
cfs_rq->tasks_timeline = RB_ROOT;
INIT_LIST_HEAD(&cfs_rq->tasks);
-#ifdef CONFIG_FAIR_GROUP_SCHED
- cfs_rq->rq = rq;
- /* allow initial update_cfs_load() to truncate */
-#ifdef CONFIG_SMP
- cfs_rq->load_stamp = 1;
-#endif
-#endif
cfs_rq->min_vruntime = (u64)(-(1LL << 20));
#ifndef CONFIG_64BIT
cfs_rq->min_vruntime_copy = cfs_rq->min_vruntime;
@@ -7928,13 +7882,9 @@ static void init_rt_rq(struct rt_rq *rt_rq, struct rq *rq)
/* delimiter for bitsearch: */
__set_bit(MAX_RT_PRIO, array->bitmap);
-#if defined CONFIG_SMP || defined CONFIG_RT_GROUP_SCHED
+#if defined CONFIG_SMP
rt_rq->highest_prio.curr = MAX_RT_PRIO;
-#ifdef CONFIG_SMP
rt_rq->highest_prio.next = MAX_RT_PRIO;
-#endif
-#endif
-#ifdef CONFIG_SMP
rt_rq->rt_nr_migratory = 0;
rt_rq->overloaded = 0;
plist_head_init(&rt_rq->pushable_tasks);
@@ -7944,11 +7894,6 @@ static void init_rt_rq(struct rt_rq *rt_rq, struct rq *rq)
rt_rq->rt_throttled = 0;
rt_rq->rt_runtime = 0;
raw_spin_lock_init(&rt_rq->rt_runtime_lock);
-
-#ifdef CONFIG_RT_GROUP_SCHED
- rt_rq->rt_nr_boosted = 0;
- rt_rq->rq = rq;
-#endif
}
#ifdef CONFIG_FAIR_GROUP_SCHED
@@ -7957,11 +7902,17 @@ static void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq,
struct sched_entity *parent)
{
struct rq *rq = cpu_rq(cpu);
- tg->cfs_rq[cpu] = cfs_rq;
- init_cfs_rq(cfs_rq, rq);
+
cfs_rq->tg = tg;
+ cfs_rq->rq = rq;
+#ifdef CONFIG_SMP
+ /* allow initial update_cfs_load() to truncate */
+ cfs_rq->load_stamp = 1;
+#endif
+ tg->cfs_rq[cpu] = cfs_rq;
tg->se[cpu] = se;
+
/* se could be NULL for root_task_group */
if (!se)
return;
@@ -7984,12 +7935,14 @@ static void init_tg_rt_entry(struct task_group *tg, struct rt_rq *rt_rq,
{
struct rq *rq = cpu_rq(cpu);
- tg->rt_rq[cpu] = rt_rq;
- init_rt_rq(rt_rq, rq);
+ rt_rq->highest_prio.curr = MAX_RT_PRIO;
+ rt_rq->rt_nr_boosted = 0;
+ rt_rq->rq = rq;
rt_rq->tg = tg;
- rt_rq->rt_runtime = tg->rt_bandwidth.rt_runtime;
+ tg->rt_rq[cpu] = rt_rq;
tg->rt_se[cpu] = rt_se;
+
if (!rt_se)
return;
@@ -8071,7 +8024,7 @@ void __init sched_init(void)
rq->nr_running = 0;
rq->calc_load_active = 0;
rq->calc_load_update = jiffies + LOAD_FREQ;
- init_cfs_rq(&rq->cfs, rq);
+ init_cfs_rq(&rq->cfs);
init_rt_rq(&rq->rt, rq);
#ifdef CONFIG_FAIR_GROUP_SCHED
root_task_group.shares = root_task_group_load;
@@ -8185,7 +8138,7 @@ void __init sched_init(void)
scheduler_running = 1;
}
-#ifdef CONFIG_DEBUG_SPINLOCK_SLEEP
+#ifdef CONFIG_DEBUG_ATOMIC_SLEEP
static inline int preempt_count_equals(int preempt_offset)
{
int nested = (preempt_count() & ~PREEMPT_ACTIVE) + rcu_preempt_depth();
@@ -8195,7 +8148,6 @@ static inline int preempt_count_equals(int preempt_offset)
void __might_sleep(const char *file, int line, int preempt_offset)
{
-#ifdef in_atomic
static unsigned long prev_jiffy; /* ratelimiting */
if ((preempt_count_equals(preempt_offset) && !irqs_disabled()) ||
@@ -8217,7 +8169,6 @@ void __might_sleep(const char *file, int line, int preempt_offset)
if (irqs_disabled())
print_irqtrace_events(current);
dump_stack();
-#endif
}
EXPORT_SYMBOL(__might_sleep);
#endif
@@ -8376,6 +8327,7 @@ int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent)
if (!se)
goto err_free_rq;
+ init_cfs_rq(cfs_rq);
init_tg_cfs_entry(tg, cfs_rq, se, i, parent->se[i]);
}
@@ -8403,7 +8355,7 @@ static inline void unregister_fair_sched_group(struct task_group *tg, int cpu)
list_del_leaf_cfs_rq(tg->cfs_rq[cpu]);
raw_spin_unlock_irqrestore(&rq->lock, flags);
}
-#else /* !CONFG_FAIR_GROUP_SCHED */
+#else /* !CONFIG_FAIR_GROUP_SCHED */
static inline void free_fair_sched_group(struct task_group *tg)
{
}
@@ -8424,7 +8376,8 @@ static void free_rt_sched_group(struct task_group *tg)
{
int i;
- destroy_rt_bandwidth(&tg->rt_bandwidth);
+ if (tg->rt_se)
+ destroy_rt_bandwidth(&tg->rt_bandwidth);
for_each_possible_cpu(i) {
if (tg->rt_rq)
@@ -8465,6 +8418,8 @@ int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent)
if (!rt_se)
goto err_free_rq;
+ init_rt_rq(rt_rq, cpu_rq(i));
+ rt_rq->rt_runtime = tg->rt_bandwidth.rt_runtime;
init_tg_rt_entry(tg, rt_rq, rt_se, i, parent->rt_se[i]);
}