From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 41615C25B75 for ; Sat, 1 Jun 2024 00:38:34 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 9C8996B0093; Fri, 31 May 2024 20:38:33 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 978C36B009E; Fri, 31 May 2024 20:38:33 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 840306B00A0; Fri, 31 May 2024 20:38:33 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0012.hostedemail.com [216.40.44.12]) by kanga.kvack.org (Postfix) with ESMTP id 5D2056B0093 for ; Fri, 31 May 2024 20:38:33 -0400 (EDT) Received: from smtpin13.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay06.hostedemail.com (Postfix) with ESMTP id 0DB83A098E for ; Sat, 1 Jun 2024 00:38:33 +0000 (UTC) X-FDA: 82180458906.13.3EE0667 Received: from sin.source.kernel.org (sin.source.kernel.org [145.40.73.55]) by imf06.hostedemail.com (Postfix) with ESMTP id A12B5180009 for ; Sat, 1 Jun 2024 00:38:30 +0000 (UTC) Authentication-Results: imf06.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b=XEPfHq95; spf=pass (imf06.hostedemail.com: domain of akpm@linux-foundation.org designates 145.40.73.55 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org; dmarc=none ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1717202311; a=rsa-sha256; cv=none; b=D6f5PVSnLq49Vxa/GgcekiZIbg2faDZBJuIfu0qC8qUxsOIg/Nndah8HbRECM4lEBMPHYJ //aE0wVg4549K9gPpU3dy3EoNL8xeKVvdrL7OBUDqsgjZPFkpN3DrW846q6SRkUeSyX1ks 7AsJbuH0s/DrNiK8ScqpOXyRFZcio/4= ARC-Authentication-Results: i=1; imf06.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b=XEPfHq95; spf=pass (imf06.hostedemail.com: domain of akpm@linux-foundation.org designates 145.40.73.55 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org; dmarc=none ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1717202311; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=fH5dPlv1fPxQyqWIDMk4JP2Z7wsugQaKZITzDLIa3L4=; b=3CtU1R1FipUMpQtwduY6oQVVIXL2eQJsoGZjNKeVQ/DOjSVyDIaBoP12hsZgTNK6npPITQ jcgMlblUzlwAdbywISMKcQhC5z6KqrvQ722S8X6x0bsAitFznQx4gROW1QL2KZKxkSxvB+ jIFBdd0jn3aGcFTUhkXgOabiMY3jfWs= Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sin.source.kernel.org (Postfix) with ESMTP id 83109CE1B94; Sat, 1 Jun 2024 00:38:26 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4326CC116B1; Sat, 1 Jun 2024 00:38:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1717202304; bh=4hmjM0UxydhUZza82YHCth9Sj1TFopzUWYdExi8Y+ps=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=XEPfHq95tZ1aJQMXPja1E8IqZy4rexHmWp0iBOOB0OTCFho8Ql7VXEbGMzYigg3hd JjHiPLp3BFSTHPZwBzry59vy+fTxRAuDunP8li0et+GKwmB8ZgG8lWdyZ8DPubGIA8 Em/a/V2spFlZopuIqcVPUKi2KOCXslvHZ3Q10FLM= Date: Fri, 31 May 2024 17:38:23 -0700 From: Andrew Morton To: Pasha Tatashin Cc: Shakeel Butt , jpoimboe@kernel.org, kent.overstreet@linux.dev, peterz@infradead.org, nphamcs@gmail.com, cerasuolodomenico@gmail.com, surenb@google.com, lizhijian@fujitsu.com, willy@infradead.org, vbabka@suse.cz, ziy@nvidia.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH v3] vmstat: Kernel stack usage histogram Message-Id: <20240531173823.4ec7b4693a4e433b1da91e75@linux-foundation.org> In-Reply-To: References: <20240530170259.852088-1-pasha.tatashin@soleen.com> X-Mailer: Sylpheed 3.8.0beta1 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: A12B5180009 X-Rspam-User: X-Rspamd-Server: rspam12 X-Stat-Signature: x6xwuge717jgocmbf7eg8mmpxodj3rit X-HE-Tag: 1717202310-95513 X-HE-Meta: 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 v0p+60DA eadii5E/dkl/3nvBrU3M2baouuEVgghwmG5uqtd4wZR+mM4gn5Z/lEtj6/sIQp+lNv703cgnrj5chiE/B1tVXlbSz3CsNaK3mk/HydM1P0mER+ytQskIAJQ5jRCcDmBOuca8g2wBCXBrKRz962HSTjQ/0NphC2/BcsyWv2o2bY4fI4J8b6kyEJoyOShFXyS6E/rHxKOyVTQd35nyrINntRZ89E1GyeQXJT8boc904yhwsOPhaWnWMqMhaHzx5THb3t0LHonENByDb8wUdUuhBDna2G7ZrUnOUyOoi X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Thu, 30 May 2024 20:14:17 -0400 Pasha Tatashin wrote: > > Couple of questions: > > > > 1. In future with your on-demand kstack allocation feature, will these > > metrics still be useful? (I think so but I want to know your take) I do think the changelog for this patch should reference the dynamic stack feature. It strengthens the justification for adding this patch. > It depends on how on-demand allocation is implemented. On hardware > that supports faults on kernel stacks, we will have other metrics that > show the total number of pages allocated for stacks. On hardware where > faults are not supported, we will most likely have some optimization > where only some threads are extended, and for those, these metrics > will still be very useful. Also useful changelog info for this patch. Pasha, could you please prepare some additional text which I can paste in? Thanks.