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SubjectRe: [tip:timers/urgent] tick: Fix oneshot broadcast setup really
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Am 19.04.2012 um 10:29 schrieb Thomas Gleixner:

> On Wed, 18 Apr 2012, Suresh Siddha wrote:
>> On Wed, 2012-04-18 at 17:31 +0200, Thomas Gleixner wrote:
>> From: Suresh Siddha <suresh.b.siddha@intel.com>
>> Subject: tick: Fix the spurious broadcast timer ticks
>>
>> During resume, tick_resume_broadcast() programs the broadcast timer
>> in oneshot mode unconditionally. On the platforms where broadcast timer
>> is not really required, this will generate spurious broadcast timer ticks
>> upon resume. For example, on the always running apic timer platforms with
>> HPET, I see spurious hpet tick once every ~5minutes (which is the 32-bit
>> hpet counter wraparound time).
>>
>> Similar to boot time, during resume make the oneshot mode setting of
>> the broadcast clock event device conditional on the state of active broadcast
>> users.
>>
>> Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
>
> Sven, Santosh, can you confirm that this works for you on top of the
> other two patches?

Works for me, thanks.

>> ---
>> kernel/time/tick-broadcast.c | 3 ++-
>> 1 files changed, 2 insertions(+), 1 deletions(-)
>>
>> diff --git a/kernel/time/tick-broadcast.c b/kernel/time/tick-broadcast.c
>> index bf57abd..766cd82 100644
>> --- a/kernel/time/tick-broadcast.c
>> +++ b/kernel/time/tick-broadcast.c
>> @@ -346,7 +346,8 @@ int tick_resume_broadcast(void)
>> tick_get_broadcast_mask());
>> break;
>> case TICKDEV_MODE_ONESHOT:
>> - broadcast = tick_resume_broadcast_oneshot(bc);
>> + if (!cpumask_empty(tick_get_broadcast_mask()))
>> + broadcast = tick_resume_broadcast_oneshot(bc);
>> break;
>> }
>> }



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