From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-20.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 86A89C433ED for ; Wed, 12 May 2021 10:29:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 46FA7613FC for ; Wed, 12 May 2021 10:29:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231361AbhELKar (ORCPT ); Wed, 12 May 2021 06:30:47 -0400 Received: from Galois.linutronix.de ([193.142.43.55]:50550 "EHLO galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230415AbhELK3j (ORCPT ); Wed, 12 May 2021 06:29:39 -0400 Date: Wed, 12 May 2021 10:28:29 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1620815310; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=1cDvnlLgJnlpX5hGJ8jiKNhhEhx6z82lpjP5ic7YRPM=; b=JSRdQkZylpbTjfkr/+WSehyDheEzUJgc5IQau6Wjb78L8DpwQskcO2peFna/Fn+oZ4qXmX MMWHsQby2K699jAx2uQcYiD//j8suZFYiUmvuIqtd6T2vJGGWMwjunRTGEuW8TEvTirK3U db+TCN7HoWFH9VjSmKUxsXRXqPs+MUbKKfQTw7hdfCJLGWwFGmRjAlqrDMDln3XRAEgNQh BkpdiMpHmZboR+ZhpJvwmHxhwWK/rKJ76IniNsBc6k/k+QJNKGPSTwbMf8TSeoEryqSetB zVUokTvtKCaznFnU1RCgzkZVushTfbXK9IUZ0S4JkrVtvUTS26TDXP4fY7XjZg== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1620815310; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=1cDvnlLgJnlpX5hGJ8jiKNhhEhx6z82lpjP5ic7YRPM=; b=rmEqycGfCRUbXFGTKIMUsZzy7lq/3zXSo/Y3UODI2W7Mr2LiGLuq9AqfhEpMDkMtPcDPUG 3pvgF3iH7XPOt/Cg== From: "tip-bot2 for Peter Zijlstra" Sender: tip-bot2@linutronix.de Reply-to: linux-kernel@vger.kernel.org To: linux-tip-commits@vger.kernel.org Subject: [tip: sched/core] delayacct: Add static_branch in scheduler hooks Cc: "Peter Zijlstra (Intel)" , Thomas Gleixner , Ingo Molnar , Balbir Singh , Johannes Weiner , x86@kernel.org, linux-kernel@vger.kernel.org In-Reply-To: <20210505111525.248028369@infradead.org> References: <20210505111525.248028369@infradead.org> MIME-Version: 1.0 Message-ID: <162081530948.29796.14722409380598313239.tip-bot2@tip-bot2> Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The following commit has been merged into the sched/core branch of tip: Commit-ID: eee4d9fee2544389e5ce5697ed92db67c86d7a9f Gitweb: https://git.kernel.org/tip/eee4d9fee2544389e5ce5697ed92db67c86d7a9f Author: Peter Zijlstra AuthorDate: Tue, 04 May 2021 22:43:36 +02:00 Committer: Peter Zijlstra CommitterDate: Wed, 12 May 2021 11:43:25 +02:00 delayacct: Add static_branch in scheduler hooks Cheaper when delayacct is disabled. Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Thomas Gleixner Reviewed-by: Ingo Molnar Acked-by: Balbir Singh Acked-by: Johannes Weiner Link: https://lkml.kernel.org/r/20210505111525.248028369@infradead.org --- include/linux/delayacct.h | 8 ++++++++ kernel/delayacct.c | 3 +++ 2 files changed, 11 insertions(+) diff --git a/include/linux/delayacct.h b/include/linux/delayacct.h index 21651f9..57fefa5 100644 --- a/include/linux/delayacct.h +++ b/include/linux/delayacct.h @@ -58,8 +58,10 @@ struct task_delay_info { #include #include +#include #ifdef CONFIG_TASK_DELAY_ACCT +DECLARE_STATIC_KEY_TRUE(delayacct_key); extern int delayacct_on; /* Delay accounting turned on/off */ extern struct kmem_cache *delayacct_cache; extern void delayacct_init(void); @@ -114,6 +116,9 @@ static inline void delayacct_tsk_free(struct task_struct *tsk) static inline void delayacct_blkio_start(void) { + if (!static_branch_likely(&delayacct_key)) + return; + delayacct_set_flag(current, DELAYACCT_PF_BLKIO); if (current->delays) __delayacct_blkio_start(); @@ -121,6 +126,9 @@ static inline void delayacct_blkio_start(void) static inline void delayacct_blkio_end(struct task_struct *p) { + if (!static_branch_likely(&delayacct_key)) + return; + if (p->delays) __delayacct_blkio_end(p); delayacct_clear_flag(p, DELAYACCT_PF_BLKIO); diff --git a/kernel/delayacct.c b/kernel/delayacct.c index 3a0b910..63012fd 100644 --- a/kernel/delayacct.c +++ b/kernel/delayacct.c @@ -14,6 +14,7 @@ #include #include +DEFINE_STATIC_KEY_TRUE(delayacct_key); int delayacct_on __read_mostly = 1; /* Delay accounting turned on/off */ struct kmem_cache *delayacct_cache; @@ -28,6 +29,8 @@ void delayacct_init(void) { delayacct_cache = KMEM_CACHE(task_delay_info, SLAB_PANIC|SLAB_ACCOUNT); delayacct_tsk_init(&init_task); + if (!delayacct_on) + static_branch_disable(&delayacct_key); } void __delayacct_tsk_init(struct task_struct *tsk)