From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 74B7F3A1CFF for ; Tue, 24 Feb 2026 16:35:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771950926; cv=none; b=Qn4Mfjy1OrmuAavNrQI6YH+VPxD+ASidrj9BJvCexYqIFqznLqatmzFkzPvFyLAcjiG6PBuY4bkpaKpdoVC5eOreGi2D++9eyHhdrFttIrgHMF6WwZgCYaMht7oC5KEhcQd3gNEV6R+7ME+SIKDCfg6cNLzfWgBBEKg2TaZ2R1o= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771950926; c=relaxed/simple; bh=rMZAJWrhL8BgmOoOgH8dEGVxSuL5IPlNY+fpOUJAc14=; h=Date:Message-ID:From:To:Cc:Subject:References:MIME-Version: Content-Type; b=i0Ilmra79mCT/mmpbQKMMLnCR71zUBYfl0t7NHoIbZLXobArT7O7OEeK9y0XdnZSLZAmC2QjnYw/YVfB/0yzC7Tt+q0oT61/7cYDIfSXkXAHFCqfNqHnXyFzpCCy398u9+s0//ZZQjHc0V95X8Las54wIUGCJ/Jz9ws4DnBRoMo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Dn5j9WJm; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Dn5j9WJm" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6D66DC19423; Tue, 24 Feb 2026 16:35:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1771950926; bh=rMZAJWrhL8BgmOoOgH8dEGVxSuL5IPlNY+fpOUJAc14=; h=Date:From:To:Cc:Subject:References:From; b=Dn5j9WJmTm82gvrapb2eqLzaPh1ZUoZl9nkBIw0E7VYs2ZjOFAGidGC+149Jw2ZVH SfGiQQwWE3mfCsuzCkwryCSaTZYr+IFrwQjHOgr5Rf8M++iZ3Yfm+ZajmSJ2VI5j// H6Mqcw/viPQkfNO2jpm82rsDpYmBtAgymDlUuKiwUfO+DSedda7XHC7hxVJoVCvtI2 TheSkZw58te+dsdIC85zC0qtvhDZMWk32VJWiRVKD/plU//mz2+7lbVYugYxgOYPA+ Z6gHy0euHJKytILqmr66Wa5XH4SFcbHM1QohERCgasjEXhfWqlg0uR6rqwDZjcTdv5 P/Zsi/1IxnPkA== Date: Tue, 24 Feb 2026 17:35:22 +0100 Message-ID: <20260224163428.866374835@kernel.org> User-Agent: quilt/0.68 From: Thomas Gleixner To: LKML Cc: Anna-Maria Behnsen , John Stultz , Stephen Boyd , Daniel Lezcano , Juri Lelli , Vincent Guittot , Dietmar Eggemann , Steven Rostedt , Ben Segall , Mel Gorman , Valentin Schneider , x86@kernel.org, Peter Zijlstra , Frederic Weisbecker , Eric Dumazet Subject: [patch 02/48] sched/fair: Simplify hrtick_update() References: <20260224163022.795809588@kernel.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=UTF-8 From: Peter Zijlstra (Intel) hrtick_update() was needed when the slice depended on nr_running, all that code is gone. All that remains is starting the hrtick when nr_running becomes more than 1. Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Thomas Gleixner --- --- kernel/sched/fair.c | 12 ++++-------- kernel/sched/sched.h | 4 ++++ 2 files changed, 8 insertions(+), 8 deletions(-) --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -6769,9 +6769,7 @@ static void hrtick_start_fair(struct rq } /* - * called from enqueue/dequeue and updates the hrtick when the - * current task is from our class and nr_running is low enough - * to matter. + * Called on enqueue to start the hrtick when h_nr_queued becomes more than 1. */ static void hrtick_update(struct rq *rq) { @@ -6780,6 +6778,9 @@ static void hrtick_update(struct rq *rq) if (!hrtick_enabled_fair(rq) || donor->sched_class != &fair_sched_class) return; + if (hrtick_active(rq)) + return; + hrtick_start_fair(rq, donor); } #else /* !CONFIG_SCHED_HRTICK: */ @@ -7102,9 +7103,6 @@ static int dequeue_entities(struct rq *r WARN_ON_ONCE(!task_sleep); WARN_ON_ONCE(p->on_rq != 1); - /* Fix-up what dequeue_task_fair() skipped */ - hrtick_update(rq); - /* * Fix-up what block_task() skipped. * @@ -7138,8 +7136,6 @@ static bool dequeue_task_fair(struct rq /* * Must not reference @p after dequeue_entities(DEQUEUE_DELAYED). */ - - hrtick_update(rq); return true; } --- a/kernel/sched/sched.h +++ b/kernel/sched/sched.h @@ -3041,6 +3041,10 @@ static inline int hrtick_enabled_dl(stru } extern void hrtick_start(struct rq *rq, u64 delay); +static inline bool hrtick_active(struct rq *rq) +{ + return hrtimer_active(&rq->hrtick_timer); +} #else /* !CONFIG_SCHED_HRTICK: */