From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.21]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D020E155C82 for ; Sat, 5 Jul 2025 14:16:04 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.175.65.21 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751724967; cv=none; b=P1FKxODPZPC1tXjq8qiYKmOwrjjp/fPQws7ApM8M5kh5MumTyzZQpFU+m+sS32c/OHU2oOZ0FTer57JRp+V1X6pyzsI1PZ9VAQ/EqVCT2YfCxYA/4i/eV06MoEWuW8/xBjxDot/nJ9lhfPRA0yWmx2BnYP9JaeCejgtKpAmHNwQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751724967; c=relaxed/simple; bh=A4cUfru2n7vPoeaTc8J+nKwy41BFBAX5DrVrWB/g3OM=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=VGBMUZulMmFuYN2JGMtk/L2TlRy7h+xsNL8mVGPc8iQykH2lT0DSiSmJbn2jV4T0uNGjxkrq7KR0DZeo1f6vhD+KRa+yhjEg3N2UwDUfakQgm58PwOdIniULEHgZrzV+OSTTZN9m7guvoxY5iTmIWUDnGhpfG0CWpVPDAe3h1Ew= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com; spf=pass smtp.mailfrom=intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=S83RRbS3; arc=none smtp.client-ip=198.175.65.21 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="S83RRbS3" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1751724965; x=1783260965; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=A4cUfru2n7vPoeaTc8J+nKwy41BFBAX5DrVrWB/g3OM=; b=S83RRbS39leQkR0Li8Hq9M9+bAA9PBRbiflBrAqoqfjhZHHYGOHwDX0D yGIV7sp2sDx3FFSOwk2uHXumM/wAw5OPNi3WbhUJhhDe3P+zVeLYMGis8 F20Tlead+H8BMc7CO5mqMXI8kSJAAH2ozDQLUGkwoaQa9uGPlSEFiAh1Q Hq2F2sbFfPprN85VVOp14EQZBNMyDqMmBFih/KwE/6rj6d9pe+pflOYfO smZwojS++ewP1e0zaKDz3Jr3baK3aYrG8SExfe0kIVpFlojtiVJ3bt4VK l61YR6CDNd8BHNGvjxtDC7XEbQMtm7opILK2QOYDFyTvVYtZqMH7jRK3I w==; X-CSE-ConnectionGUID: qMpYuY5dTUmA+J3tHT+Itw== X-CSE-MsgGUID: McAcqdgATgyoroOpMyOzMA== X-IronPort-AV: E=McAfee;i="6800,10657,11485"; a="53891987" X-IronPort-AV: E=Sophos;i="6.16,290,1744095600"; d="scan'208";a="53891987" Received: from orviesa008.jf.intel.com ([10.64.159.148]) by orvoesa113.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 05 Jul 2025 07:16:04 -0700 X-CSE-ConnectionGUID: Df/EWjQ2RsuXS0UAzlUrZg== X-CSE-MsgGUID: K7s1JiCORDSWhEDy3bbqSg== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.16,290,1744095600"; d="scan'208";a="155309790" Received: from lkp-server01.sh.intel.com (HELO 0b2900756c14) ([10.239.97.150]) by orviesa008.jf.intel.com with ESMTP; 05 Jul 2025 07:16:02 -0700 Received: from kbuild by 0b2900756c14 with local (Exim 4.96) (envelope-from ) id 1uY3gN-0004XJ-0l; Sat, 05 Jul 2025 14:15:59 +0000 Date: Sat, 5 Jul 2025 22:15:31 +0800 From: kernel test robot To: Vincent Guittot , mingo@redhat.com, peterz@infradead.org, juri.lelli@redhat.com, dietmar.eggemann@arm.com, rostedt@goodmis.org, bsegall@google.com, mgorman@suse.de, vschneid@redhat.com, dhaval@gianis.ca, linux-kernel@vger.kernel.org Cc: oe-kbuild-all@lists.linux.dev, Vincent Guittot Subject: Re: [PATCH v2 3/6] sched/fair: Remove spurious shorter slice preemption Message-ID: <202507052215.5HznxNGI-lkp@intel.com> References: <20250704143612.998419-4-vincent.guittot@linaro.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250704143612.998419-4-vincent.guittot@linaro.org> Hi Vincent, kernel test robot noticed the following build warnings: [auto build test WARNING on tip/sched/core] [also build test WARNING on peterz-queue/sched/core linus/master v6.16-rc4 next-20250704] [If your patch is applied to the wrong git tree, kindly drop us a note. And when submitting patch, we suggest to use '--base' as documented in https://git-scm.com/docs/git-format-patch#_base_tree_information] url: https://github.com/intel-lab-lkp/linux/commits/Vincent-Guittot/sched-fair-Use-protect_slice-instead-of-direct-comparison/20250704-223850 base: tip/sched/core patch link: https://lore.kernel.org/r/20250704143612.998419-4-vincent.guittot%40linaro.org patch subject: [PATCH v2 3/6] sched/fair: Remove spurious shorter slice preemption config: s390-randconfig-r072-20250705 (https://download.01.org/0day-ci/archive/20250705/202507052215.5HznxNGI-lkp@intel.com/config) compiler: s390-linux-gcc (GCC) 11.5.0 If you fix the issue in a separate patch/commit (i.e. not just a new version of the same patch/commit), kindly add following tags | Reported-by: kernel test robot | Closes: https://lore.kernel.org/oe-kbuild-all/202507052215.5HznxNGI-lkp@intel.com/ smatch warnings: kernel/sched/fair.c:8721 check_preempt_wakeup_fair() warn: inconsistent indenting vim +8721 kernel/sched/fair.c 8643 8644 /* 8645 * Preempt the current task with a newly woken task if needed: 8646 */ 8647 static void check_preempt_wakeup_fair(struct rq *rq, struct task_struct *p, int wake_flags) 8648 { 8649 struct task_struct *donor = rq->donor; 8650 struct sched_entity *se = &donor->se, *pse = &p->se; 8651 struct cfs_rq *cfs_rq = task_cfs_rq(donor); 8652 int cse_is_idle, pse_is_idle; 8653 bool do_preempt_short = false; 8654 8655 if (unlikely(se == pse)) 8656 return; 8657 8658 /* 8659 * This is possible from callers such as attach_tasks(), in which we 8660 * unconditionally wakeup_preempt() after an enqueue (which may have 8661 * lead to a throttle). This both saves work and prevents false 8662 * next-buddy nomination below. 8663 */ 8664 if (unlikely(throttled_hierarchy(cfs_rq_of(pse)))) 8665 return; 8666 8667 if (sched_feat(NEXT_BUDDY) && !(wake_flags & WF_FORK) && !pse->sched_delayed) { 8668 set_next_buddy(pse); 8669 } 8670 8671 /* 8672 * We can come here with TIF_NEED_RESCHED already set from new task 8673 * wake up path. 8674 * 8675 * Note: this also catches the edge-case of curr being in a throttled 8676 * group (e.g. via set_curr_task), since update_curr() (in the 8677 * enqueue of curr) will have resulted in resched being set. This 8678 * prevents us from potentially nominating it as a false LAST_BUDDY 8679 * below. 8680 */ 8681 if (test_tsk_need_resched(rq->curr)) 8682 return; 8683 8684 if (!sched_feat(WAKEUP_PREEMPTION)) 8685 return; 8686 8687 find_matching_se(&se, &pse); 8688 WARN_ON_ONCE(!pse); 8689 8690 cse_is_idle = se_is_idle(se); 8691 pse_is_idle = se_is_idle(pse); 8692 8693 /* 8694 * Preempt an idle entity in favor of a non-idle entity (and don't preempt 8695 * in the inverse case). 8696 */ 8697 if (cse_is_idle && !pse_is_idle) { 8698 /* 8699 * When non-idle entity preempt an idle entity, 8700 * don't give idle entity slice protection. 8701 */ 8702 do_preempt_short = true; 8703 goto preempt; 8704 } 8705 8706 if (cse_is_idle != pse_is_idle) 8707 return; 8708 8709 /* 8710 * BATCH and IDLE tasks do not preempt others. 8711 */ 8712 if (unlikely(!normal_policy(p->policy))) 8713 return; 8714 8715 cfs_rq = cfs_rq_of(se); 8716 update_curr(cfs_rq); 8717 /* 8718 * If @p has a shorter slice than current and @p is eligible, override 8719 * current's slice protection in order to allow preemption. 8720 */ > 8721 do_preempt_short = sched_feat(PREEMPT_SHORT) && (pse->slice < se->slice); 8722 8723 /* 8724 * If @p has become the most eligible task, force preemption. 8725 */ 8726 if (__pick_eevdf(cfs_rq, !do_preempt_short) == pse) 8727 goto preempt; 8728 8729 return; 8730 8731 preempt: 8732 if (do_preempt_short) 8733 cancel_protect_slice(se); 8734 8735 resched_curr_lazy(rq); 8736 } 8737 -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests/wiki