sched: Cure nr_iowait_cpu() users
Commit 0224cf4c5e (sched: Intoduce get_cpu_iowait_time_us())
broke things by not making sure preemption was indeed disabled
by the callers of nr_iowait_cpu() which took the iowait value of
the current cpu.
This resulted in a heap of preempt warnings. Cure this by making
nr_iowait_cpu() take a cpu number and fix up the callers to pass
in the right number.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Maxim Levitsky <maximlevitsky@gmail.com>
Cc: Len Brown <len.brown@intel.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: linux-pm@lists.linux-foundation.org
LKML-Reference: <1277968037.1868.120.camel@laptop>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/drivers/cpuidle/governors/menu.c b/drivers/cpuidle/governors/menu.c
index 52ff8aa..1b128702 100644
--- a/drivers/cpuidle/governors/menu.c
+++ b/drivers/cpuidle/governors/menu.c
@@ -143,7 +143,7 @@
* 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 @@
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;
}
diff --git a/include/linux/sched.h b/include/linux/sched.h
index f118809..747fcae 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -139,7 +139,7 @@
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);
diff --git a/kernel/sched.c b/kernel/sched.c
index a24d6d5..f87abe3 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -2864,9 +2864,9 @@
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);
}
diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index 1d7b9bc..1a6f828 100644
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -154,14 +154,14 @@
* 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 @@
{
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 @@
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 @@
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 @@
*/
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
