From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (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 1A5112882AC for ; Fri, 10 Oct 2025 12:14:08 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.129.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760098450; cv=none; b=lr37nmc2OomeurV21zJhwruOjBAV2tkxB9nUnTLei49B0FuwsjUooe5JVOSUTFW4Mxiz4bDHvsHXqcXQGV2PhhNOoH/NF2dxOqmd0YKKuKBMnRfPp8MQpQZ2wWEM0J9HQIp67lQzhr2G9SqkBwAr9XvyfTnjautzseAbQDdWjfo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760098450; c=relaxed/simple; bh=rh6LqMn/kBv5tK2CsLcwzQ/R+KHSy8KPC4B8H2brwE4=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=SAXelC+uIlz6SEf7C9non3rFoFluOvliHkqp2PG7ivsjkH6/Fzgwk80WrwT6fdvnAIpeDbJtZQ0eXm0SYvSglYmFlOAO6ZZ4fOgAxDpjY52CmnGTCEGy86N3EI0zqDFEnUPA6VAl8xo1xffeUtX7f49OFD/ivbPjOSA60rc7iJE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=HYeJmTnu; arc=none smtp.client-ip=170.10.129.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="HYeJmTnu" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1760098448; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=wSkOIftXAt2OwtwNgaMsmMKEvqLB/8flG6WLRBIhQdY=; b=HYeJmTnumTsj4zFzJ4pS4KlzA3NypxMu1HucbKal4qND+1SS0g3rGkOEmR0uzn/pYjsCNO wa62sUA7zuaSSB/Ms0ahlBhYrhAOJ4zN1DM/MHBB988L6jm6cefOW9OT1PfVmaJEpM1+IC B6HW5Li/sGUoM8gp05D/EogBB8YA04w= Received: from mx-prod-mc-08.mail-002.prod.us-west-2.aws.redhat.com (ec2-35-165-154-97.us-west-2.compute.amazonaws.com [35.165.154.97]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-347-L-HFnwOvODWqe12ifXHNTQ-1; Fri, 10 Oct 2025 08:14:04 -0400 X-MC-Unique: L-HFnwOvODWqe12ifXHNTQ-1 X-Mimecast-MFC-AGG-ID: L-HFnwOvODWqe12ifXHNTQ_1760098442 Received: from mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.12]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-08.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 46BA31800447; Fri, 10 Oct 2025 12:14:02 +0000 (UTC) Received: from pauld.westford.csb (unknown [10.22.88.193]) by mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 555B719560BB; Fri, 10 Oct 2025 12:13:57 +0000 (UTC) Date: Fri, 10 Oct 2025 08:13:54 -0400 From: Phil Auld To: frederic@kernel.org Cc: bsegall@google.com, dietmar.eggemann@arm.com, juri.lelli@redhat.com, linux-kernel@vger.kernel.org, mgorman@suse.de, mingo@redhat.com, peterz@infradead.org, rostedt@goodmis.org, tanghui20@huawei.com, tglx@linutronix.de, vincent.guittot@linaro.org, wangtao554@huawei.com, zhangqiao22@huawei.com, Waiman Long Subject: Re: [PATCH] sched: Increase sched_tick_remote timeout Message-ID: <20251010121354.GA408475@pauld.westford.csb> References: <20250911161300.437944-1-pauld@redhat.com> <20250923104739.GA514793@pauld.westford.csb> 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: <20250923104739.GA514793@pauld.westford.csb> X-Scanned-By: MIMEDefang 3.0 on 10.30.177.12 On Tue, Sep 23, 2025 at 06:47:39AM -0400 Phil Auld wrote: > Hi, > > On Thu, Sep 11, 2025 at 12:13:00PM -0400 Phil Auld wrote: > > Increase the sched_tick_remote WARN_ON timeout to remove false > > positives due to temporarily busy HK cpus. The suggestion > > was 30 seconds to catch really stuck remote tick processing > > but not trigger it too easily. > > > > Signed-off-by: Phil Auld > > Suggested-by: Frederic Weisbecker > > Cc: Peter Zijlstra > > Cc: Frederic Weisbecker > > Frederic ack'd this. Any other thoughts or opinions on this one > character patch? Ping... > > Cheers, > Phil > > > > > --- > > kernel/sched/core.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/kernel/sched/core.c b/kernel/sched/core.c > > index be00629f0ba4..ef90d358252d 100644 > > --- a/kernel/sched/core.c > > +++ b/kernel/sched/core.c > > @@ -5724,7 +5724,7 @@ static void sched_tick_remote(struct work_struct *work) > > * reasonable amount of time. > > */ > > u64 delta = rq_clock_task(rq) - curr->se.exec_start; > > - WARN_ON_ONCE(delta > (u64)NSEC_PER_SEC * 3); > > + WARN_ON_ONCE(delta > (u64)NSEC_PER_SEC * 30); > > } > > curr->sched_class->task_tick(rq, curr, 0); > > > > -- > > 2.51.0 > > > > -- > > --