[RFC][PATCH 1/7] ARM: OMAP4: cpuidle - Remove unused valid field

Jean Pihet jean.pihet at newoldbits.com
Wed Mar 21 13:28:52 UTC 2012


On Wed, Mar 21, 2012 at 11:03 AM, Santosh Shilimkar
<santosh.shilimkar at ti.com> wrote:
> On Wednesday 21 March 2012 03:16 PM, Daniel Lezcano wrote:
>> On 03/21/2012 10:41 AM, Shilimkar, Santosh wrote:
>>> On Wed, Mar 21, 2012 at 2:57 PM, Daniel Lezcano
>>> <daniel.lezcano at linaro.org>  wrote:
>>>> The 'valid' field is never used in the code, let's remove it.
>>>>
>>>> Signed-off-by: Daniel Lezcano<daniel.lezcano at linaro.org>
>>>> ---
>>> It is used during the registration. This field has been very useful for
>>> debug when need to disable a C-state etc.
>>> So unless and until there is a strong reason, i would like to retain it.
>>
>> IMO if it used for debug purpose, it should be moved to the debug code
>> and if the debug code is not upstream, then that 'valid' should not be
>> here but in the out-of-tree code.
>>
> When I said debug, I mean CPUIDLE debug and not any special debug code.
>
>> By the way, this may be a debate for nothing because a patchset is on
>> the way to disable C-states from sysfs.
>>
> I see but sysfs won't solve that because you want to disable certain
> C-state so that CPUIDLE driver don't use that state.
This will solve the problem, the only difference is that you need the
user space to switch the disable knob from sysfs.
>From the kernel space, for debug, you can set the .disable value to 1
in the cpuidle_driver->states struct.

>
> Let say if the C4 which is OSWR is broken. In such cases, just
> setting valid flag let you disable it.
>
> Again I don't have strong objection to this change.
>
> Regards
> santosh

Regards,
Jean

>
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