From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from relay.hostedemail.com (smtprelay0017.hostedemail.com [216.40.44.17]) (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 78EF43DE420 for ; Wed, 18 Mar 2026 14:48:03 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=216.40.44.17 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773845287; cv=none; b=fq67ThePdX9vVyX3ZRA1c4I62+yofPWBTnlh32pFL/Jqmq+DQlHY/bRLZz4tonAjW9IWSfCwJs8aGngHRnikrmj9EAvYyoK9Rkjei9dKWibPk1puLcy8nW/KHaawMlmoN0MxLTXvnJf6V1jl/YNsnGgxeGkuhi5qF78jEn3uvM4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773845287; c=relaxed/simple; bh=IIDp9VuQ6lJngFY4uLAdK2iaIwTh1R6BfnEAVYj1HnY=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=kJkYpdSvF+WVr8vhL0L3ko6aUvhWZKucrmdTRphZBGoFH+3HuSoozbk0XqJIYPQ8wJ1cHs4YqVfvgTUnU3BXoaHxSAsxyJoS/NGqWOetRJsZ6TnQeO7ifmzVvcJPaPqVKY479ig9rk1tAyrBI2ac7qA05/Q7W7WvLhGnfe9A33U= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=goodmis.org; spf=pass smtp.mailfrom=goodmis.org; arc=none smtp.client-ip=216.40.44.17 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=goodmis.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=goodmis.org Received: from omf20.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay06.hostedemail.com (Postfix) with ESMTP id 660AC1B8A01; Wed, 18 Mar 2026 14:48:01 +0000 (UTC) Received: from [HIDDEN] (Authenticated sender: rostedt@goodmis.org) by omf20.hostedemail.com (Postfix) with ESMTPA id 06E4020027; Wed, 18 Mar 2026 14:47:58 +0000 (UTC) Date: Wed, 18 Mar 2026 10:48:26 -0400 From: Steven Rostedt To: Shrikanth Hegde Cc: Peter Zijlstra , Joseph Salisbury , Ingo Molnar , Juri Lelli , Vincent Guittot , Dietmar Eggemann , Ben Segall , Mel Gorman , Valentin Schneider , linux-kernel@vger.kernel.org Subject: Re: [PATCH] sched/core: initialize resched_latency in sched_tick() Message-ID: <20260318104826.64ccbe09@gandalf.local.home> In-Reply-To: References: <20260317195807.98850-1-joseph.salisbury@oracle.com> <20260317170943.44c41263@gandalf.local.home> X-Mailer: Claws Mail 3.20.0git84 (GTK+ 2.24.33; x86_64-pc-linux-gnu) 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-Transfer-Encoding: 7bit X-Rspamd-Server: rspamout07 X-Rspamd-Queue-Id: 06E4020027 X-Stat-Signature: c7z9epf79kjibupi8fc9b4cdipuk1tda X-Session-Marker: 726F737465647440676F6F646D69732E6F7267 X-Session-ID: U2FsdGVkX1/8US0wrczj6rOmcGp692FXPvchxl1QOv8= X-HE-Tag: 1773845278-904857 X-HE-Meta: U2FsdGVkX1/5QmqzMVPSZteUjkpREeLR+JsZRoigbfJLpn6BEuIkqDCAF85uYI6mXJE2ytqp7D5o6MGI0tr9k9fu3LdvSzEIo7R8NrTOZ8WgXXYHBxGGV7sPoZ6syfa5iFFaeloCIjfzK+G1mSQGZKKKjr6bg4oy6RTabU28DJH5kAUdjkarfNmkZINcg+hX5ixGEl87sUPo7/aMrZ7kUs180BX46htZqvIkiRpp0hEYI5qdVWDvBcb0UuDd02ki5hcn5LLpkhioGloqdjPLf+ed/o9CZhzLbOb0AXh3xWyBYWNI9YYRdQxy6crg/Nf3okeLoGnhcygRc+wzGaELxIKkU/VafrJF On Wed, 18 Mar 2026 12:00:58 +0530 Shrikanth Hegde wrote: > Whats the relevance of resched_latency warnings in the age of preempt > kernels being the default for majority of the archs. > > In case of full/lazy preemption, at the end of sched_tick itself we would call > schedule if need_resched is set provided it was preemptible. > > It kind of makes sense for non preemptive kernels. But we have preemptoff and > preemptirqoff tracers which one could use. (although may need a kernel build) > > What bugs is it catching these days? Good point. I've never used it. I guess the question is, does anyone? -- Steve