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

* 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  sched: Cure nr_iowait_cpu() users
  init: Fix comment
  init, sched: Fix race between init and kthreadd
This commit is contained in:
Linus Torvalds 2010-07-02 09:52:58 -07:00
commit 123f94f22e
5 changed files with 25 additions and 13 deletions

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@ -143,7 +143,7 @@ static inline int which_bucket(unsigned int duration)
* This allows us to calculate
* E(duration)|iowait
*/
if (nr_iowait_cpu())
if (nr_iowait_cpu(smp_processor_id()))
bucket = BUCKETS/2;
if (duration < 10)
@ -175,7 +175,7 @@ static inline int performance_multiplier(void)
mult += 2 * get_loadavg();
/* for IO wait tasks (per cpu!) we add 5x each */
mult += 10 * nr_iowait_cpu();
mult += 10 * nr_iowait_cpu(smp_processor_id());
return mult;
}

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@ -139,7 +139,7 @@ extern int nr_processes(void);
extern unsigned long nr_running(void);
extern unsigned long nr_uninterruptible(void);
extern unsigned long nr_iowait(void);
extern unsigned long nr_iowait_cpu(void);
extern unsigned long nr_iowait_cpu(int cpu);
extern unsigned long this_cpu_load(void);

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@ -424,18 +424,26 @@ static void __init setup_command_line(char *command_line)
* gcc-3.4 accidentally inlines this function, so use noinline.
*/
static __initdata DECLARE_COMPLETION(kthreadd_done);
static noinline void __init_refok rest_init(void)
__releases(kernel_lock)
{
int pid;
rcu_scheduler_starting();
/*
* We need to spawn init first so that it obtains pid 1, however
* the init task will end up wanting to create kthreads, which, if
* we schedule it before we create kthreadd, will OOPS.
*/
kernel_thread(kernel_init, NULL, CLONE_FS | CLONE_SIGHAND);
numa_default_policy();
pid = kernel_thread(kthreadd, NULL, CLONE_FS | CLONE_FILES);
rcu_read_lock();
kthreadd_task = find_task_by_pid_ns(pid, &init_pid_ns);
rcu_read_unlock();
complete(&kthreadd_done);
unlock_kernel();
/*
@ -857,6 +865,10 @@ static noinline int init_post(void)
static int __init kernel_init(void * unused)
{
/*
* Wait until kthreadd is all set-up.
*/
wait_for_completion(&kthreadd_done);
lock_kernel();
/*

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@ -2873,9 +2873,9 @@ unsigned long nr_iowait(void)
return sum;
}
unsigned long nr_iowait_cpu(void)
unsigned long nr_iowait_cpu(int cpu)
{
struct rq *this = this_rq();
struct rq *this = cpu_rq(cpu);
return atomic_read(&this->nr_iowait);
}

View File

@ -154,14 +154,14 @@ static void tick_nohz_update_jiffies(ktime_t now)
* Updates the per cpu time idle statistics counters
*/
static void
update_ts_time_stats(struct tick_sched *ts, ktime_t now, u64 *last_update_time)
update_ts_time_stats(int cpu, struct tick_sched *ts, ktime_t now, u64 *last_update_time)
{
ktime_t delta;
if (ts->idle_active) {
delta = ktime_sub(now, ts->idle_entrytime);
ts->idle_sleeptime = ktime_add(ts->idle_sleeptime, delta);
if (nr_iowait_cpu() > 0)
if (nr_iowait_cpu(cpu) > 0)
ts->iowait_sleeptime = ktime_add(ts->iowait_sleeptime, delta);
ts->idle_entrytime = now;
}
@ -175,19 +175,19 @@ static void tick_nohz_stop_idle(int cpu, ktime_t now)
{
struct tick_sched *ts = &per_cpu(tick_cpu_sched, cpu);
update_ts_time_stats(ts, now, NULL);
update_ts_time_stats(cpu, ts, now, NULL);
ts->idle_active = 0;
sched_clock_idle_wakeup_event(0);
}
static ktime_t tick_nohz_start_idle(struct tick_sched *ts)
static ktime_t tick_nohz_start_idle(int cpu, struct tick_sched *ts)
{
ktime_t now;
now = ktime_get();
update_ts_time_stats(ts, now, NULL);
update_ts_time_stats(cpu, ts, now, NULL);
ts->idle_entrytime = now;
ts->idle_active = 1;
@ -216,7 +216,7 @@ u64 get_cpu_idle_time_us(int cpu, u64 *last_update_time)
if (!tick_nohz_enabled)
return -1;
update_ts_time_stats(ts, ktime_get(), last_update_time);
update_ts_time_stats(cpu, ts, ktime_get(), last_update_time);
return ktime_to_us(ts->idle_sleeptime);
}
@ -242,7 +242,7 @@ u64 get_cpu_iowait_time_us(int cpu, u64 *last_update_time)
if (!tick_nohz_enabled)
return -1;
update_ts_time_stats(ts, ktime_get(), last_update_time);
update_ts_time_stats(cpu, ts, ktime_get(), last_update_time);
return ktime_to_us(ts->iowait_sleeptime);
}
@ -284,7 +284,7 @@ void tick_nohz_stop_sched_tick(int inidle)
*/
ts->inidle = 1;
now = tick_nohz_start_idle(ts);
now = tick_nohz_start_idle(cpu, ts);
/*
* If this cpu is offline and it is the one which updates