From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel Lezcano Subject: Re: [PATCH V2 3/5] cpuidle: idle: menu: Don't reflect when a state selection failed Date: Tue, 28 Oct 2014 19:28:02 +0100 Message-ID: <544FE032.5050900@linaro.org> References: <1414054881-17713-1-git-send-email-daniel.lezcano@linaro.org> <1414054881-17713-3-git-send-email-daniel.lezcano@linaro.org> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Received: from mail-wi0-f170.google.com ([209.85.212.170]:46693 "EHLO mail-wi0-f170.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750722AbaJ1S2I (ORCPT ); Tue, 28 Oct 2014 14:28:08 -0400 Received: by mail-wi0-f170.google.com with SMTP id n3so9652486wiv.1 for ; Tue, 28 Oct 2014 11:28:06 -0700 (PDT) In-Reply-To: Sender: linux-pm-owner@vger.kernel.org List-Id: linux-pm@vger.kernel.org To: Preeti Murthy Cc: "Rafael J. Wysocki" , Nicolas Pitre , "linux-pm@vger.kernel.org" , LKML , Peter Zijlstra , Lists linaro-kernel , patches@linaro.org, Preeti U Murthy On 10/28/2014 08:01 AM, Preeti Murthy wrote: > On Thu, Oct 23, 2014 at 2:31 PM, Daniel Lezcano > wrote: >> In the current code, the check to reflect or not the outcoming state= is done >> against the idle state which has been chosen and its value. >> >> Instead of doing a check in each of the reflect functions, just don'= t call reflect >> if something went wrong in the idle path. >> >> Signed-off-by: Daniel Lezcano >> Acked-by: Nicolas Pitre >> --- >> drivers/cpuidle/governors/ladder.c | 3 +-- >> drivers/cpuidle/governors/menu.c | 4 +--- >> kernel/sched/idle.c | 3 ++- >> 3 files changed, 4 insertions(+), 6 deletions(-) >> >> diff --git a/drivers/cpuidle/governors/ladder.c b/drivers/cpuidle/go= vernors/ladder.c >> index fb396d6..c0b36a8 100644 >> --- a/drivers/cpuidle/governors/ladder.c >> +++ b/drivers/cpuidle/governors/ladder.c >> @@ -165,8 +165,7 @@ static int ladder_enable_device(struct cpuidle_d= river *drv, >> static void ladder_reflect(struct cpuidle_device *dev, int index) >> { >> struct ladder_device *ldev =3D &__get_cpu_var(ladder_device= s); >> - if (index > 0) >> - ldev->last_state_idx =3D index; >> + ldev->last_state_idx =3D index; >> } >> >> static struct cpuidle_governor ladder_governor =3D { >> diff --git a/drivers/cpuidle/governors/menu.c b/drivers/cpuidle/gove= rnors/menu.c >> index a17515f..3907301 100644 >> --- a/drivers/cpuidle/governors/menu.c >> +++ b/drivers/cpuidle/governors/menu.c >> @@ -365,9 +365,7 @@ static int menu_select(struct cpuidle_driver *dr= v, struct cpuidle_device *dev, >> static void menu_reflect(struct cpuidle_device *dev, int index) >> { >> struct menu_device *data =3D &__get_cpu_var(menu_devices); >> - data->last_state_idx =3D index; >> - if (index >=3D 0) >> - data->needs_update =3D 1; >> + data->needs_update =3D 1; > > Why is the last_state_idx not getting updated ? Oups, right. This is missing. Thanks for pointing this out. By the way, I don't think a back end driver is changing the selected=20 state currently and I am not sure this is desirable since we want to=20 trust the state we are going (as a best effort). So if the 'enter'=20 function does not change the index, that means the last_state_idx has=20 not to be changed since it has been assigned in the 'select' function. --=20 Linaro.org =E2=94=82 Open source software fo= r ARM SoCs =46ollow Linaro: Facebook | Twitter | Blog