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 E1845C433EF for ; Fri, 25 Mar 2022 23:52:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229449AbiCYXxu (ORCPT ); Fri, 25 Mar 2022 19:53:50 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58856 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229562AbiCYXxo (ORCPT ); Fri, 25 Mar 2022 19:53:44 -0400 Received: from mga07.intel.com (mga07.intel.com [134.134.136.100]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5CEA14AE33 for ; Fri, 25 Mar 2022 16:52:09 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1648252329; x=1679788329; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=mHLNNSPQ4EYmrAFhqKFt7xJOVLotEnt4YlgX3orT5jE=; b=HEeKewEyJM9Ob/1FQBjkI6q0G23b/yOLq4Bwn9Ic5cQUX+iAWM/X3yPI o/BrI9tLU4kve7jzq4ZpKagWD1LVCnmyFDzGpCllENYKYJ+EH3V5ddicP 9ORYR6U71wmoXn4sd2mVeyaflUEm2mqVCvEQ6hbpJnZdhxOvLOlPXKtmG xnhmYpEWNrLNDdU72y+4DtnZWwWVHvF81bE2LWESYvyt2quQub8iMNUGm iprWdRHQ5BOxuIaTs6Lv1cEQ9ncrrwqqTVOtL/l2BGbLyhDys+YUa9hed Pn3SoiXB54vpDaCHb0+AOWt194m90XPZ5Yq3W3mJTrB2cAKfsGgopAeJj g==; X-IronPort-AV: E=McAfee;i="6200,9189,10297"; a="321930148" X-IronPort-AV: E=Sophos;i="5.90,211,1643702400"; d="scan'208";a="321930148" Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by orsmga105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 25 Mar 2022 16:52:09 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.90,211,1643702400"; d="scan'208";a="648425294" Received: from skl-02.jf.intel.com ([10.54.74.28]) by fmsmga002.fm.intel.com with ESMTP; 25 Mar 2022 16:52:08 -0700 From: Tim Chen To: Peter Zijlstra , Vincent Guittot , Ingo Molnar , Juri Lelli Cc: Yu Chen , Walter Mack , Mel Gorman , linux-kernel@vger.kernel.org, Tim Chen Subject: [PATCH 1/2] sched/fair: Don't rely on ->exec_start for migration Date: Fri, 25 Mar 2022 15:54:16 -0700 Message-Id: <68832dfbb60fda030540b5f4e39c5801942689b1.1648228023.git.tim.c.chen@linux.intel.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Peter Zijlstra From: Peter Zijlstra (Intel) Currently migrate_task_rq_fair() (ab)uses se->exec_start to make task_hot() fail. In order to preserve ->exec_start, add a ->migrated flag to sched_entity. Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Tim Chen --- include/linux/sched.h | 1 + kernel/sched/fair.c | 6 +++++- 2 files changed, 6 insertions(+), 1 deletion(-) diff --git a/include/linux/sched.h b/include/linux/sched.h index 75ba8aa60248..0edf16b4d40a 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -541,6 +541,7 @@ struct sched_entity { struct rb_node run_node; struct list_head group_node; unsigned int on_rq; + unsigned int migrated; u64 exec_start; u64 sum_exec_runtime; diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 5146163bfabb..2498e97804fd 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -1004,6 +1004,7 @@ update_stats_curr_start(struct cfs_rq *cfs_rq, struct sched_entity *se) /* * We are starting a new run period: */ + se->migrated = 0; se->exec_start = rq_clock_task(rq_of(cfs_rq)); } @@ -6979,7 +6980,7 @@ static void migrate_task_rq_fair(struct task_struct *p, int new_cpu) p->se.avg.last_update_time = 0; /* We have migrated, no longer consider this task hot */ - p->se.exec_start = 0; + p->se.migrated = 1; update_scan_period(p, new_cpu); } @@ -7665,6 +7666,9 @@ static int task_hot(struct task_struct *p, struct lb_env *env) if (sysctl_sched_migration_cost == 0) return 0; + if (p->se.migrated) + return 0; + delta = rq_clock_task(env->src_rq) - p->se.exec_start; return delta < (s64)sysctl_sched_migration_cost; -- 2.32.0