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 ACFAB2AD0C; Thu, 17 Apr 2025 20:12:38 +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=1744920758; cv=none; b=gcmkD1pZ+unE8X34FVls7OkRInyX1SyHTvXZUSEpkdpwOhBL8vKX6plwOZux9WiTJdrAfskjPYj8V9lerHI51PPBkrkcECZHgjAIAngh0eabD6rvPHJSxbp+m0jZ38sJcq7fIk/H+x9ktwRKzCIFj9n+uGhd4htR1uChOjEQzog= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1744920758; c=relaxed/simple; bh=0YpGtHMUawX1ATSiuC8hsCCXgN6stiffyM1wwPmYrys=; h=Date:From:To:Cc:Subject:Message-Id:In-Reply-To:References: Mime-Version:Content-Type; b=Ks2WMM8e6g5Fm9S/ho1dS7P3PRjQDMCq4bzlp+LQd3Zr4mhfNj45YyPTCIHIC3llcuCpVTJCylC0TtAsIxBRy0OaKwIBkRQoGT+7b4ueHE2u8zKUSnJ0ojNfd1ldcu/SEU3s+Uh0n3MBdMmySLiGf9qNbsOu8p+sCQ8thmh9ZOk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b=0ap1dEvM; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="0ap1dEvM" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6BB23C4CEE4; Thu, 17 Apr 2025 20:12:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1744920758; bh=0YpGtHMUawX1ATSiuC8hsCCXgN6stiffyM1wwPmYrys=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=0ap1dEvMcMQhNVxw8JwbcsNMW5gQ1fyqZjG3esAIQOfcmxlBgSLnL42sB0lUOnwuZ 5FM+yPY45aQR8283cPYigHYzb7wepQtQ4JTBjD821nQ8hPxHOjUerUbt+w3uG2cjBE 38hpEmeDqmBXHe4Q4x22IRrMJtAiq7fJwVooNd3s= Date: Thu, 17 Apr 2025 13:12:36 -0700 From: Andrew Morton To: Libo Chen Cc: peterz@infradead.org, mgorman@suse.de, mingo@redhat.com, juri.lelli@redhat.com, vincent.guittot@linaro.org, tj@kernel.org, rostedt@goodmis.org, llong@redhat.com, kprateek.nayak@amd.com, raghavendra.kt@amd.com, yu.c.chen@intel.com, tim.c.chen@intel.com, vineethr@linux.ibm.com, chris.hyser@oracle.com, daniel.m.jordan@oracle.com, lorenzo.stoakes@oracle.com, mkoutny@suse.com, Dhaval.Giani@amd.com, cgroups@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v3 0/2] sched/numa: Skip VMA scanning on memory pinned Message-Id: <20250417131236.c47ce477c0e68dbb06a4fabb@linux-foundation.org> In-Reply-To: <20250417191543.1781862-1-libo.chen@oracle.com> References: <20250417191543.1781862-1-libo.chen@oracle.com> X-Mailer: Sylpheed 3.7.0 (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 On Thu, 17 Apr 2025 12:15:41 -0700 Libo Chen wrote: > v1->v2: > 1. add perf improvment numbers in commit log. Yet to find perf diff on > will-it-scale, so not included here. Plan to run more workloads. > 2. add tracepoint. > 3. To peterz's comment, this will make it impossible to attract tasks to > those memory just like other VMA skippings. This is the current > implementation, I think we can improve that in the future, but at the > moment it's probabaly better to keep it consistent. > > v2->v3: > 1. add enable_cpuset() based on Mel's suggestion but again I think it's > redundant > 2. print out nodemask with %*p.. format in the tracepoint I do agree with Mel - bitmap_weight() is somewhat expensive and cpusets_enabled() is super fast. So the benefit to cpusets_enabled()=false kernels will exceed to cost to cpusets_enabled()=true kernels. This isn't traditionally mm.git material, but it's close. I'll grab the patchset for some testing. and shall drop it again if it turns up via another tree.