From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755768Ab2IQNvf (ORCPT ); Mon, 17 Sep 2012 09:51:35 -0400 Received: from mga03.intel.com ([143.182.124.21]:23963 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755601Ab2IQNv2 (ORCPT ); Mon, 17 Sep 2012 09:51:28 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.80,435,1344236400"; d="scan'208";a="145899804" From: Youquan Song To: linux-kernel@vger.kernel.org, linux-acpi@vger.kernel.org, arjan@linux.intel.com, lenb@kernel.org Cc: Rik van Riel , Youquan Song , Youquan Song Subject: [PATCH V2 3/3] x86,idle: Set residency to 0 if target Cstate not really enter Date: Mon, 17 Sep 2012 21:53:29 -0400 Message-Id: <1347933209-25939-4-git-send-email-youquan.song@intel.com> X-Mailer: git-send-email 1.6.4.2 In-Reply-To: <1347933209-25939-3-git-send-email-youquan.song@intel.com> References: <1347933209-25939-1-git-send-email-youquan.song@intel.com> <1347933209-25939-2-git-send-email-youquan.song@intel.com> <1347933209-25939-3-git-send-email-youquan.song@intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org When cpuidle governor choose a C-state to enter for idle CPU, but it notice that there is tasks request to be executed. So the idle CPU will not really enter the target C-state and go to run task. In this situation, it will use the residency of previous really entered target C-states. Obviously, it is not reasonable. So, this patch fix it by set the target C-state residency to 0. Signed-off-by: Youquan Song --- drivers/cpuidle/cpuidle.c | 1 + 1 files changed, 1 insertions(+), 0 deletions(-) diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c index 2f0083a..7992417 100644 --- a/drivers/cpuidle/cpuidle.c +++ b/drivers/cpuidle/cpuidle.c @@ -136,6 +136,10 @@ int cpuidle_idle_call(void) /* ask the governor for the next state */ next_state = cpuidle_curr_governor->select(drv, dev); if (need_resched()) { + dev->last_residency = 0; + /* give the governor an opportunity to reflect on the outcome */ + if (cpuidle_curr_governor->reflect) + cpuidle_curr_governor->reflect(dev, next_state); local_irq_enable(); return 0; }