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| author | Thomas Gleixner <tglx@linutronix.de> | 2007-03-17 00:25:52 +0100 |
|---|---|---|
| committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-03-16 19:35:25 -0700 |
| commit | cd05a1f818073a623455a58e756c5b419fc98db9 (patch) | |
| tree | 4e148e96f00fe07b0c53a379e812344733e8484a /kernel/time/tick-broadcast.c | |
| parent | 24c4ac070adffe4a21f3a8daf4aee7c98fa6c4f9 (diff) | |
| download | linux-cd05a1f818073a623455a58e756c5b419fc98db9.tar.gz linux-cd05a1f818073a623455a58e756c5b419fc98db9.tar.bz2 linux-cd05a1f818073a623455a58e756c5b419fc98db9.zip | |
[PATCH] clockevents: Fix suspend/resume to disk hangs
I finally found a dual core box, which survives suspend/resume without
crashing in the middle of nowhere. Sigh, I never figured out from the
code and the bug reports what's going on.
The observed hangs are caused by a stale state transition of the clock
event devices, which keeps the RCU synchronization away from completion,
when the non boot CPU is brought back up.
The suspend/resume in oneshot mode needs the similar care as the
periodic mode during suspend to RAM. My assumption that the state
transitions during the different shutdown/bringups of s2disk would go
through the periodic boot phase and then switch over to highres resp.
nohz mode were simply wrong.
Add the appropriate suspend / resume handling for the non periodic
modes.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'kernel/time/tick-broadcast.c')
| -rw-r--r-- | kernel/time/tick-broadcast.c | 27 |
1 files changed, 22 insertions, 5 deletions
diff --git a/kernel/time/tick-broadcast.c b/kernel/time/tick-broadcast.c index 5567745470f7..eadfce2fff74 100644 --- a/kernel/time/tick-broadcast.c +++ b/kernel/time/tick-broadcast.c @@ -307,12 +307,19 @@ int tick_resume_broadcast(void) spin_lock_irqsave(&tick_broadcast_lock, flags); bc = tick_broadcast_device.evtdev; - if (bc) { - if (tick_broadcast_device.mode == TICKDEV_MODE_PERIODIC && - !cpus_empty(tick_broadcast_mask)) - tick_broadcast_start_periodic(bc); - broadcast = cpu_isset(smp_processor_id(), tick_broadcast_mask); + if (bc) { + switch (tick_broadcast_device.mode) { + case TICKDEV_MODE_PERIODIC: + if(!cpus_empty(tick_broadcast_mask)) + tick_broadcast_start_periodic(bc); + broadcast = cpu_isset(smp_processor_id(), + tick_broadcast_mask); + break; + case TICKDEV_MODE_ONESHOT: + broadcast = tick_resume_broadcast_oneshot(bc); + break; + } } spin_unlock_irqrestore(&tick_broadcast_lock, flags); @@ -347,6 +354,16 @@ static int tick_broadcast_set_event(ktime_t expires, int force) } } +int tick_resume_broadcast_oneshot(struct clock_event_device *bc) +{ + clockevents_set_mode(bc, CLOCK_EVT_MODE_ONESHOT); + + if(!cpus_empty(tick_broadcast_oneshot_mask)) + tick_broadcast_set_event(ktime_get(), 1); + + return cpu_isset(smp_processor_id(), tick_broadcast_oneshot_mask); +} + /* * Reprogram the broadcast device: * |