Re: [PATCH] cpuidle: Measure idle state durations with monotonic clock

2012-11-27 Thread Rafael J. Wysocki
On Wednesday, November 14, 2012 05:56:30 PM Julius Werner wrote: > Many cpuidle drivers measure their time spent in an idle state by > reading the wallclock time before and after idling and calculating the > difference. This leads to erroneous results when the wallclock time gets > updated by anoth

Re: [PATCH] cpuidle: Measure idle state durations with monotonic clock

2012-11-26 Thread Len Brown
>> drivers/idle/intel_idle.c | 14 +- Acked-by: Len Brown thanks! -Len ___ linaro-dev mailing list linaro-dev@lists.linaro.org http://lists.linaro.org/mailman/listinfo/linaro-dev

Re: [PATCH] cpuidle: Measure idle state durations with monotonic clock

2012-11-26 Thread Len Brown
On 11/15/2012 04:04 AM, Preeti Murthy wrote: > Hi all, > > The code looks correct and inviting to me as it has led to good cleanups. > I dont think passing 0 as the argument to the function > sched_clock_idle_wakeup_event() > should lead to problems,as it does not do anything useful with the > pas

Re: [PATCH] cpuidle: Measure idle state durations with monotonic clock

2012-11-20 Thread Rafael J. Wysocki
On Wednesday, November 14, 2012 05:56:30 PM Julius Werner wrote: > Many cpuidle drivers measure their time spent in an idle state by > reading the wallclock time before and after idling and calculating the > difference. This leads to erroneous results when the wallclock time gets > updated by anoth

Re: [PATCH] cpuidle: Measure idle state durations with monotonic clock

2012-11-15 Thread Preeti Murthy
Hi all, The code looks correct and inviting to me as it has led to good cleanups. I dont think passing 0 as the argument to the function sched_clock_idle_wakeup_event() should lead to problems,as it does not do anything useful with the passed arguments. My only curiosity is what was the purpose o

Re: [PATCH] cpuidle: Measure idle state durations with monotonic clock

2012-11-15 Thread Daniel Lezcano
On 11/15/2012 02:56 AM, Julius Werner wrote: > Many cpuidle drivers measure their time spent in an idle state by > reading the wallclock time before and after idling and calculating the > difference. This leads to erroneous results when the wallclock time gets > updated by another processor in the

Re: [PATCH] cpuidle: Measure idle state durations with monotonic clock

2012-11-14 Thread Julius Werner
> Maybe you can remove all these computations and set the flag > en_core_tk_irqen for the driver ? That will be handled by the cpuidle > framework, no ? > > Same comment for the intel_idle driver. Yeah, I thought about that, too. I was a little too afraid of touching the sched_clock_idle_wakeup_ev

Re: [PATCH] cpuidle: Measure idle state durations with monotonic clock

2012-11-14 Thread Daniel Lezcano
On 11/13/2012 10:52 PM, Julius Werner wrote: > Many cpuidle drivers measure their time spent in an idle state by > reading the wallclock time before and after idling and calculating the > difference. This leads to erroneous results when the wallclock time gets > updated by another processor in the