From patchwork Sun Aug 12 16:09:27 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Leo Yan X-Patchwork-Id: 10563679 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 19B06139A for ; Sun, 12 Aug 2018 16:10:03 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 01BE729467 for ; Sun, 12 Aug 2018 16:10:03 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id E66A629466; Sun, 12 Aug 2018 16:10:02 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id B1A3529467 for ; Sun, 12 Aug 2018 16:10:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727699AbeHLSs2 (ORCPT ); Sun, 12 Aug 2018 14:48:28 -0400 Received: from mail-wm0-f68.google.com ([74.125.82.68]:53850 "EHLO mail-wm0-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728180AbeHLSs1 (ORCPT ); Sun, 12 Aug 2018 14:48:27 -0400 Received: by mail-wm0-f68.google.com with SMTP id s9-v6so6473899wmh.3 for ; Sun, 12 Aug 2018 09:09:56 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=7syOievGKU1gnJa8oh05y8DUlQgWF5NjJ3xt3wLMcp0=; b=Aqw4vA0xT3WxMfTUxnd2mwPWd8CNO/XKIvCXki9jTDnHbOsEpUGb8lNr5DxnTeREod RtqC2bdKn0+llD37F45FFVZkE3+SCLiR5wyX/knNX9M8hLOei8vErZgtXqz8CuzNhE1W OtoVDdXcF8fJUARQ4SjmDJL1uS57JPBz+gdfk= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=7syOievGKU1gnJa8oh05y8DUlQgWF5NjJ3xt3wLMcp0=; b=e/odI49FNjEI3P0KulXdZXbVAy90exRzVZ2CjPsRSwMXk4YK9NVC0zVG6aXj2QOrM0 cGUms0jypV1l03YfOwnc4ux8+piUNpWKNlhuId+guRayRvLk/lVWdf96AVZNIDMcjXeA tr8u1AZOpw4Spb66HpjcEO9oU7nrxLisIKrJFNhepBMWfiicu4uQy6CRrqFSVGSLpUYE ZbsNvYCg9F/yZm0IJR3Xtscjs1UKIjYL4FteTo3U8Auc17xzZXUcXyUCmde53HdVUsUa Hxa4J1B8Tn2XtCIpXP1gdxojTztVxdhRE8VrDL3VW4j9y3ME5/r7VHq91HiVXnCKU5WP /m6A== X-Gm-Message-State: AOUpUlGzHPPXPdedY6z6k0N3kB70HIepSxiTuTmJwjPo14W/MhNKrNIt jEe6yypwVqX39s/2/E9ed0ygLw== X-Google-Smtp-Source: AA+uWPw7s5O072Udhi0wx1PE6Pr4V4AHd6MaUxCYSajv11b1UuYlphjFpTQ/V31jboWyqOhGW9JodQ== X-Received: by 2002:a1c:28c2:: with SMTP id o185-v6mr6159731wmo.40.1534090195777; Sun, 12 Aug 2018 09:09:55 -0700 (PDT) Received: from localhost.localdomain ([45.76.138.171]) by smtp.gmail.com with ESMTPSA id t6-v6sm7437369wmf.8.2018.08.12.09.09.52 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Sun, 12 Aug 2018 09:09:55 -0700 (PDT) From: Leo Yan To: "Rafael J. Wysocki" , "Peter Zijlstra (Intel)" , Daniel Lezcano , Vincent Guittot , Ramesh Thomas , linux-kernel@vger.kernel.org, Linux PM Cc: Leo Yan Subject: [PATCH v1 1/5] cpuidle: menu: Clean up variables usage in menu_select() Date: Mon, 13 Aug 2018 00:09:27 +0800 Message-Id: <1534090171-14464-2-git-send-email-leo.yan@linaro.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1534090171-14464-1-git-send-email-leo.yan@linaro.org> References: <1534090171-14464-1-git-send-email-leo.yan@linaro.org> Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP The usage for two variables 'data->predicted_us' and 'expected_interval' in menu_select() are confused, especially these two variables are assigned with each other: firstly 'data->predicted_us' is assigned to the minimum value between 'data->predicted_us' and 'expected_interval', so it presents the prediction period for taking account different factors and include consideration for expected interval; but later 'data->predicted_us' is assigned back to 'expected_interval' and from then on the function uses 'expected_interval' to select idle state; this results in 'expected_interval' has two different semantics between the top half and the bottom half of the same function. This patch is to clean up the usage of these two variables, we always use 'data->predicted_us' to present the idle duration predictions and it can be used to compare with idle state target residency or tick boundary for choosing idle state; we purely use 'expected_interval' to record the expected interval value, which is mainly for interval interrupt estimation. Signed-off-by: Leo Yan --- drivers/cpuidle/governors/menu.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/drivers/cpuidle/governors/menu.c b/drivers/cpuidle/governors/menu.c index 5eb7d6f..b972db1 100644 --- a/drivers/cpuidle/governors/menu.c +++ b/drivers/cpuidle/governors/menu.c @@ -363,7 +363,6 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev, latency_req = interactivity_req; select: - expected_interval = data->predicted_us; /* * Find the idle state with the lowest power while satisfying * our constraints. @@ -386,7 +385,7 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev, * expected idle duration so that the tick is retained * as long as that target residency is low enough. */ - expected_interval = drv->states[idx].target_residency; + data->predicted_us = drv->states[idx].target_residency; break; } idx = i; @@ -400,7 +399,7 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev, * expected idle duration is shorter than the tick period length. */ if (((drv->states[idx].flags & CPUIDLE_FLAG_POLLING) || - expected_interval < TICK_USEC) && !tick_nohz_tick_stopped()) { + data->predicted_us < TICK_USEC) && !tick_nohz_tick_stopped()) { unsigned int delta_next_us = ktime_to_us(delta_next); *stop_tick = false;