linux-kernel - Re: [PATCH] cpuidle: governor: menu: move repeated correction factor check to init

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Tue, 22 Apr 2014 17:56:39 +0530
From:	Chander Kashyap <chander.kashyap@...aro.org>
To:	"Rafael J. Wysocki" <rjw@...ysocki.net>
Cc:	Tuukka Tikkanen <tuukka.tikkanen@...aro.org>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	rafael.j.wysocki@...el.com,
	Daniel Lezcano <daniel.lezcano@...aro.org>,
	linux-pm@...r.kernel.org
Subject: Re: [PATCH] cpuidle: governor: menu: move repeated correction factor
 check to init

On 22 April 2014 16:54, Rafael J. Wysocki <rjw@...ysocki.net> wrote:
> On Tuesday, April 22, 2014 03:24:21 PM Chander Kashyap wrote:
>> +cc
>> linux-pm@...r.kernel.org.
>
> And can you please resend the patch?  So that it shows up in Patchwork,
> for example?
>

Yes i will resend it again.

>
>> On 22 April 2014 15:33, Rafael J. Wysocki <rjw@...ysocki.net> wrote:
>> > On Tuesday, April 22, 2014 08:27:53 AM Chander Kashyap wrote:
>> >> ping
>> >
>> > Please CC cpuidle patches to linux-pm@...r.kernel.org.
>>
>> +cc to linux-pm@...r.kernel.org.
>> Thanks Rafael
>>
>> >
>> > Thanks!
>> >
>> >> On 10 April 2014 19:57, Tuukka Tikkanen <tuukka.tikkanen@...aro.org> wrote:
>> >> > On 10 April 2014 16:43, Chander Kashyap <chander.kashyap@...aro.org> wrote:
>> >> >> In menu_select function we check for correction factor every time.
>> >> >> If it is zero we are initializing to unity. Hence move it to init function
>> >> >> and initialise by unity, hence avoid repeated comparisons.
>> >> >>
>> >> >> Signed-off-by: Chander Kashyap <chander.kashyap@...aro.org>
>> >> >> ---
>> >> >>  drivers/cpuidle/governors/menu.c |   15 ++++++++-------
>> >> >>  1 file changed, 8 insertions(+), 7 deletions(-)
>> >> >>
>> >> >> diff --git a/drivers/cpuidle/governors/menu.c b/drivers/cpuidle/governors/menu.c
>> >> >> index cf7f2f0..048f6d9 100644
>> >> >> --- a/drivers/cpuidle/governors/menu.c
>> >> >> +++ b/drivers/cpuidle/governors/menu.c
>> >> >> @@ -315,13 +315,6 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev)
>> >> >>         multiplier = performance_multiplier();
>> >> >>
>> >> >>         /*
>> >> >> -        * if the correction factor is 0 (eg first time init or cpu hotplug
>> >> >> -        * etc), we actually want to start out with a unity factor.
>> >> >> -        */
>> >> >> -       if (data->correction_factor[data->bucket] == 0)
>> >> >> -               data->correction_factor[data->bucket] = RESOLUTION * DECAY;
>> >> >> -
>> >> >> -       /*
>> >> >>          * Force the result of multiplication to be 64 bits even if both
>> >> >>          * operands are 32 bits.
>> >> >>          * Make sure to round up for half microseconds.
>> >> >> @@ -453,9 +446,17 @@ static int menu_enable_device(struct cpuidle_driver *drv,
>> >> >>                                 struct cpuidle_device *dev)
>> >> >>  {
>> >> >>         struct menu_device *data = &per_cpu(menu_devices, dev->cpu);
>> >> >> +       int i;
>> >> >>
>> >> >>         memset(data, 0, sizeof(struct menu_device));
>> >> >>
>> >> >> +       /*
>> >> >> +        * if the correction factor is 0 (eg first time init or cpu hotplug
>> >> >> +        * etc), we actually want to start out with a unity factor.
>> >> >> +        */
>> >> >> +       for(i = 0; i < BUCKETS; i++)
>> >> >> +               data->correction_factor[i] = RESOLUTION * DECAY;
>> >> >> +
>> >> >>         return 0;
>> >> >>  }
>> >> >>
>> >> >> --
>> >> >> 1.7.9.5
>> >> >>
>> >> >
>> >> > Reviewed-by: Tuukka Tikkanen <tuukka.tikkanen@...aro.org>
>> >>
>> >>
>> >>
>> >>
>> >
>> > --
>> > I speak only for myself.
>> > Rafael J. Wysocki, Intel Open Source Technology Center.
>>
>>
>>
>>
>
> --
> I speak only for myself.
> Rafael J. Wysocki, Intel Open Source Technology Center.



-- 
with warm regards,
Chander Kashyap
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/