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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3D0B5C433EF for ; Sun, 24 Apr 2022 20:17:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239571AbiDXUUr (ORCPT ); Sun, 24 Apr 2022 16:20:47 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35642 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232991AbiDXUUq (ORCPT ); Sun, 24 Apr 2022 16:20:46 -0400 Received: from out30-44.freemail.mail.aliyun.com (out30-44.freemail.mail.aliyun.com [115.124.30.44]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CFC8DAE79 for ; Sun, 24 Apr 2022 13:17:43 -0700 (PDT) X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R611e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e04357;MF=cruzzhao@linux.alibaba.com;NM=1;PH=DS;RN=10;SR=0;TI=SMTPD_---0VB3be3J_1650831454; Received: from rt2b04371.sqa.tbc.tbsite.net(mailfrom:CruzZhao@linux.alibaba.com fp:SMTPD_---0VB3be3J_1650831454) by smtp.aliyun-inc.com(127.0.0.1); Mon, 25 Apr 2022 04:17:41 +0800 From: Cruz Zhao To: mingo@redhat.com, peterz@infradead.org, juri.lelli@redhat.com, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, rostedt@goodmis.org, bsegall@google.com, mgorman@suse.de, bristot@redhat.com Cc: linux-kernel@vger.kernel.org Subject: [PATCH v2] sched/core: Skip sched_core_fork/free() when core sched is disabled Date: Mon, 25 Apr 2022 04:17:34 +0800 Message-Id: <1650831454-101777-1-git-send-email-CruzZhao@linux.alibaba.com> X-Mailer: git-send-email 1.8.3.1 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org As __put_task_struct() and copy_process() are hot path functions, the call of sched_core_fork/free() will bring overhead when core sched is disabled, and we skip them in these cases. Reported-by: kernel test robot Signed-off-by: Cruz Zhao --- kernel/sched/core_sched.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/kernel/sched/core_sched.c b/kernel/sched/core_sched.c index 38a2cec..72a8ef8 100644 --- a/kernel/sched/core_sched.c +++ b/kernel/sched/core_sched.c @@ -108,13 +108,16 @@ static unsigned long sched_core_clone_cookie(struct task_struct *p) void sched_core_fork(struct task_struct *p) { - RB_CLEAR_NODE(&p->core_node); - p->core_cookie = sched_core_clone_cookie(current); + if (!sched_core_disabled()) { + RB_CLEAR_NODE(&p->core_node); + p->core_cookie = sched_core_clone_cookie(current); + } } void sched_core_free(struct task_struct *p) { - sched_core_put_cookie(p->core_cookie); + if (!sched_core_disabled()) + sched_core_put_cookie(p->core_cookie); } static void __sched_core_set(struct task_struct *p, unsigned long cookie) -- 1.8.3.1