From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) (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 17D7C3376BA for ; Tue, 28 Oct 2025 14:15:22 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=90.155.92.199 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761660924; cv=none; b=YKGqOA6u1/6/GhbP8HwuxNyOQQxyxf9bABjUAKfJiXGVqWu+ErjBH/d1QdZdqoFHCe0XXWlcLLVYFihiXDaOjU+wPUlu6xsM60BpHFZbZvYa+0Clzo0oWCrK9jyffEMl3FSvrktqBMMpFPLzdqo/4txb2YKaCugEQIyXFicwiH8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761660924; c=relaxed/simple; bh=w6W58KPIqppLBJ8713spB2vK0wRO9BnnMYzmPBcmjAE=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=d3lhlxcwKyfGzCLAPm2w2Bq3HaZ9DH9V5KawCpYawZGhCH9E4ih3sCw/RQeHkyZg98yMA8WT/Qr/eMr+Qv3azb3yuvX9QDTO98mMo1Ryw9IVSEF0L+BCYRDSYLgJH0m20d7qYazSQPLYjOXtXd73TXNat6/w60gyx9AoGo3oRIE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=infradead.org; spf=none smtp.mailfrom=infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=qoHc/qo0; arc=none smtp.client-ip=90.155.92.199 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="qoHc/qo0" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=Sz8Vgt55hTJIM/bJ/oXGjLSRqQof2L2ZpnvW6wpuL5Q=; b=qoHc/qo0Xrc/I4IakGBs2dLz1Z eMMC0VQu3Uo1UOgQ9N4FM0oczjqQ8R14itQZvCZKeN3RSmWWcqTYMctn1NVgNZUqlb+WLDH1UXWjN qTQW+EtIg3XgIJMZhPSQPRCyEjxUgp4nzW4JQk4l0JXJp8oDJ/SvM2QnI65Pv3dKqvVlnkT4wV+lR LtKs5X6+lOI9scSLJCazJm8TNNM5KDCrLP1WLw4wt0SpULWPUdSB7jNdE7wYqunavUAmVzCwtw6Vc 3urCHQPePNGqCA3Lf9+9WEu4b6iROdoVhpP7UpzOqOs/1F5B35ZppG0MTBZuT2cRyF0236EREtNFO mOX2bdzw==; Received: from 77-249-17-252.cable.dynamic.v4.ziggo.nl ([77.249.17.252] helo=noisy.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.98.2 #2 (Red Hat Linux)) id 1vDjc3-00000004X0u-2dzh; Tue, 28 Oct 2025 13:19:47 +0000 Received: by noisy.programming.kicks-ass.net (Postfix, from userid 1000) id 67B39300220; Tue, 28 Oct 2025 15:15:18 +0100 (CET) Date: Tue, 28 Oct 2025 15:15:18 +0100 From: Peter Zijlstra To: Namhyung Kim Cc: Ingo Molnar , Mark Rutland , Alexander Shishkin , Arnaldo Carvalho de Melo , Ian Rogers , Adrian Hunter , LKML , Eric Dumazet Subject: Re: [PATCH] perf/x86: Add cond_resched() when allocate/release DS buffers Message-ID: <20251028141518.GA4067720@noisy.programming.kicks-ass.net> References: <20251027212724.1759322-1-namhyung@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=us-ascii Content-Disposition: inline In-Reply-To: <20251027212724.1759322-1-namhyung@kernel.org> On Mon, Oct 27, 2025 at 02:27:24PM -0700, Namhyung Kim wrote: > On large systems, it's possible to trigger sched latency warning during > the DS buffer allocation or release. Add cond_resched() to avoid it. We're >.< close to deleting cond_resched(), it makes absolutely no sense adding more.