diff options
| author | Peter Zijlstra <[email protected]> | 2010-06-17 18:02:37 +0200 |
|---|---|---|
| committer | Thomas Gleixner <[email protected]> | 2010-06-17 19:37:29 +0200 |
| commit | 3310d4d38fbc514e7b18bd3b1eea8effdd63b5aa (patch) | |
| tree | 14e2a5b6126c9b1341a3d4bf5299545ce4b1999a | |
| parent | 7e27d6e778cd87b6f2415515d7127eba53fe5d02 (diff) | |
nohz: Fix nohz ratelimit
Chris Wedgwood reports that 39c0cbe (sched: Rate-limit nohz) causes a
serial console regression, unresponsiveness, and indeed it does. The
reason is that the nohz code is skipped even when the tick was already
stopped before the nohz_ratelimit(cpu) condition changed.
Move the nohz_ratelimit() check to the other conditions which prevent
long idle sleeps.
Reported-by: Chris Wedgwood <[email protected]>
Tested-by: Brian Bloniarz <[email protected]>
Signed-off-by: Mike Galbraith <[email protected]>
Signed-off-by: Peter Zijlstra <[email protected]>
Cc: Jiri Kosina <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Greg KH <[email protected]>
Cc: Alan Cox <[email protected]>
Cc: OGAWA Hirofumi <[email protected]>
Cc: Jef Driesen <[email protected]>
LKML-Reference: <1276790557.27822.516.camel@twins>
Signed-off-by: Thomas Gleixner <[email protected]>
| -rw-r--r-- | kernel/time/tick-sched.c | 5 |
1 files changed, 1 insertions, 4 deletions
diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c index 1d7b9bc1c034..783fbadf2202 100644 --- a/kernel/time/tick-sched.c +++ b/kernel/time/tick-sched.c @@ -315,9 +315,6 @@ void tick_nohz_stop_sched_tick(int inidle) goto end; } - if (nohz_ratelimit(cpu)) - goto end; - ts->idle_calls++; /* Read jiffies and the time when jiffies were updated last */ do { @@ -328,7 +325,7 @@ void tick_nohz_stop_sched_tick(int inidle) } while (read_seqretry(&xtime_lock, seq)); if (rcu_needs_cpu(cpu) || printk_needs_cpu(cpu) || - arch_needs_cpu(cpu)) { + arch_needs_cpu(cpu) || nohz_ratelimit(cpu)) { next_jiffies = last_jiffies + 1; delta_jiffies = 1; } else { |