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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 978EBC433FE for ; Tue, 22 Mar 2022 02:47:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235639AbiCVCtO (ORCPT ); Mon, 21 Mar 2022 22:49:14 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57920 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235634AbiCVCtN (ORCPT ); Mon, 21 Mar 2022 22:49:13 -0400 Received: from mail-qk1-x72f.google.com (mail-qk1-x72f.google.com [IPv6:2607:f8b0:4864:20::72f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8E12A4A909; Mon, 21 Mar 2022 19:47:47 -0700 (PDT) Received: by mail-qk1-x72f.google.com with SMTP id i65so7286333qkd.7; Mon, 21 Mar 2022 19:47:47 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=message-id:date:from:to:cc:subject:references:mime-version :content-disposition:in-reply-to; bh=Fxbk8zHpadBwqoYmDWUAyGhNym0Al2auQQmaphKtiiI=; b=GdDoCGokDh+u7cg/P9lZNMt+SHdG22s06tywPEdHjucdE1iaWkgO6z5mcrXTCssh3m xddjQhiaAyJ4ztee0l3PHHz8SLECOipWwuo9Z7YzgGZg8l5KBQ0qahNF5OVpsIZnwmRN /3tlnx+ifjbh51aOUahVYMMmmH5G17X+aHFZ5dfw+ul/62LZhaMeVbiIeBh7H8JYfRGu 6qCUEvtXAp1iNu1l6mo4Zjgg4OYH3UOnQT4d/dt0x9x+7IL38NuWOm0Gjpd+hvxHab2l itER/2KjWfEteiY0dspt07y7Vu1awvo/eUzsZCoyjyTxH9eXl7xVohcgqD+iRxLuoOgx tPNA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:message-id:date:from:to:cc:subject:references :mime-version:content-disposition:in-reply-to; bh=Fxbk8zHpadBwqoYmDWUAyGhNym0Al2auQQmaphKtiiI=; b=V1XpMQgJUDG3hWQB9pErp/oecYM5UFyZ9QghLtyLMVz2Usg7D1F7mJk3uQEFq/Ow4x cWKObiJ7NTW+D2scdXxrOZ6n5ZZJPamWyKkc6LcPw8DPFA5uoagsci3II19MdJ1lYYTx anTgTA4C85ucWu8/lNWfmqjQeEUohfxcjSKFDuX95YG/Yih7ZBf9R/fQD6H3L10P/7TZ 5E7WK5d9fFe4zFV5SstZtRhOXGVnrjaBeeKkfIkeBZP50R7p2QIC8KraRD73vU5iE7DA RRwzLM3BwozLmO7jsOIrYgA5JBLdbS/SVP3ucP0JuOD8vT/V31ggagu2piPwPYAyJgmB 1Xmg== X-Gm-Message-State: AOAM532SfLdMKbrZbDhXQepVjixRN8W9SVMCHI9mEo+gErL7a/5680jl 51pI7JeyD5tXGiVgN1mGFMA= X-Google-Smtp-Source: ABdhPJx14QPIkLwvpLxDulgHQkSvIzJ5/A5iBQZUcX+1EpSqW2syPZ3jYTL4hxxykk4WHJUT26iQDQ== X-Received: by 2002:a05:620a:21dc:b0:67b:1209:7530 with SMTP id h28-20020a05620a21dc00b0067b12097530mr14336349qka.111.1647917266687; Mon, 21 Mar 2022 19:47:46 -0700 (PDT) Received: from localhost ([193.203.214.57]) by smtp.gmail.com with ESMTPSA id k73-20020a37a14c000000b0067b316a4161sm9076188qke.120.2022.03.21.19.47.44 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 21 Mar 2022 19:47:45 -0700 (PDT) Message-ID: <623938d1.1c69fb81.52716.030f@mx.google.com> X-Google-Original-Message-ID: <20220322024742.GA2326136@cgel.zte@gmail.com> Date: Tue, 22 Mar 2022 02:47:42 +0000 From: CGEL To: Johannes Weiner Cc: axboe@kernel.dk, viro@zeniv.linux.org.uk, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, akpm@linux-foundation.org, Yang Yang , Ran Xiaokai Subject: Re: [PATCH] block/psi: make PSI annotations of submit_bio only work for file pages References: <20220316063927.2128383-1-yang.yang29@zte.com.cn> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On Mon, Mar 21, 2022 at 10:33:20AM -0400, Johannes Weiner wrote: > On Wed, Mar 16, 2022 at 06:39:28AM +0000, cgel.zte@gmail.com wrote: > > From: Yang Yang > > > > psi tracks the time spent on submitting the IO of refaulting file pages > > and anonymous pages[1]. But after we tracks refaulting anonymous pages > > in swap_readpage[2][3], there is no need to track refaulting anonymous > > pages in submit_bio. > > > > So this patch can reduce redundant calling of psi_memstall_enter. And > > make it easier to track refaulting file pages and anonymous pages > > separately. > > I don't think this is an improvement. > > psi_memstall_enter() will check current->in_memstall once, detect the > nested call, and bail. Your patch checks PageSwapBacked for every page > being added. It's more branches for less robust code. We are also working for a new patch to classify different reasons cause psi_memstall_enter(): reclaim, thrashing, compact, etc. This will help user to tuning sysctl, for example, if user see high compact delay, he may try do adjust THP sysctl to reduce the compact delay. To support that, we should distinguish what's the reason cause psi in submit_io(), this patch does the job.