Re: [PATCH 1/2] cpuidle: acpi: Remove TIME_INVALID flag from acpi

[Daniel Lezcano <daniel.lezcano@linaro.org>]

On 11/21/2014 04:01 PM, Daniel Lezcano wrote:
> On 11/21/2014 04:05 PM, Rafael J. Wysocki wrote:
>> On Friday, November 21, 2014 10:29:51 AM Daniel Lezcano wrote:
>>> The commit 8e92b6605d introduced the TIME_VALID flag for the C1 state
>>> if this one is a mwait state assuming the interrupt will be enabled
>>> before reading the end time of the idle state.
>>>
>>> The changelog of this commit mention a potential problem with the menu
>>> governor but not a real observation and I assume it described an old
>>> code as the commit is from 2008.
>>>
>>> I have been digging through the code and I didn't find any place
>>> where the
>>> interrupts are enabled before reading the time. Moreover with the
>>> changes
>>> in the meantime, we moved the time measurements in the cpuidle core
>>> as well
>>> as the interrupts enabling making sure the time is measured before the
>>> interrupt are enabled again in a single place.
>>>
>>> Remove this test as the time measurement is always valid for this
>>> state.
>>>
>>> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
>>
>> Well, I need Len to have a look at this.

Hi,

any news on that ?

Thanks

   -- Daniel

> Ok thanks.
>
> If you have time, is it possible also you have a look at the patchset I
> sent :
>
> [PATCH V3 0/6] sched: idle: cpuidle: cleanups and fixes
>
> and give your opinion about the poll state Peter and I we were discussing ?
>
> Regards
>
>    -- Daniel
>
>>> ---
>>>   drivers/acpi/processor_idle.c | 2 --
>>>   1 file changed, 2 deletions(-)
>>>
>>> diff --git a/drivers/acpi/processor_idle.c
>>> b/drivers/acpi/processor_idle.c
>>> index 380b4b4..7afba40 100644
>>> --- a/drivers/acpi/processor_idle.c
>>> +++ b/drivers/acpi/processor_idle.c
>>> @@ -985,8 +985,6 @@ static int
>>> acpi_processor_setup_cpuidle_states(struct acpi_processor *pr)
>>>           state->flags = 0;
>>>           switch (cx->type) {
>>>               case ACPI_STATE_C1:
>>> -            if (cx->entry_method != ACPI_CSTATE_FFH)
>>> -                state->flags |= CPUIDLE_FLAG_TIME_INVALID;
>>>
>>>               state->enter = acpi_idle_enter_c1;
>>>               state->enter_dead = acpi_idle_play_dead;
>>>
>>
>
>


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