Commit b7e113dc authored Sep 22, 2007 by Thomas Gleixner Committed by Linus Torvalds Sep 22, 2007

clockevents: remove the suspend/resume workaround^Wthinko



In a desparate attempt to fix the suspend/resume problem on Andrews
VAIO I added a workaround which enforced the broadcast of the oneshot
timer on resume. This was actually resolving the problem on the VAIO
but was just a stupid workaround, which was not tackling the root
cause: the assignement of lower idle C-States in the ACPI processor_idle
code. The cpuidle patches, which utilize the dynamic tick feature and
go faster into deeper C-states exposed the problem again. The correct
solution is the previous patch, which prevents lower C-states across
the suspend/resume.

Remove the enforcement code, including the conditional broadcast timer
arming, which helped to pamper over the real problem for quite a time.
The oneshot broadcast flag for the cpu, which runs the resume code can
never be set at the time when this code is executed. It only gets set,
when the CPU is entering a lower idle C-State.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Len Brown <lenb@kernel.org>
Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent b04e7bdb

kernel/time/tick-broadcast.c

+1 −16

Original line number	Original line	Diff line number	Diff line
	@@ -382,23 +382,8 @@ static int tick_broadcast_set_event(ktime_t expires, int force)

	int tick_resume_broadcast_oneshot(struct clock_event_device *bc)		int tick_resume_broadcast_oneshot(struct clock_event_device *bc)
	{		{
	int cpu = smp_processor_id();

	/*
	* If the CPU is marked for broadcast, enforce oneshot
	* broadcast mode. The jinxed VAIO does not resume otherwise.
	* No idea why it ends up in a lower C State during resume
	* without notifying the clock events layer.
	*/
	if (cpu_isset(cpu, tick_broadcast_mask))
	cpu_set(cpu, tick_broadcast_oneshot_mask);

	clockevents_set_mode(bc, CLOCK_EVT_MODE_ONESHOT);		clockevents_set_mode(bc, CLOCK_EVT_MODE_ONESHOT);
			return 0;
	if(!cpus_empty(tick_broadcast_oneshot_mask))
	tick_broadcast_set_event(ktime_get(), 1);

	return cpu_isset(cpu, tick_broadcast_oneshot_mask);
	}		}

	/*		/*

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