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 X-Spam-Level: X-Spam-Status: No, score=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A9D76C35666 for ; Fri, 21 Feb 2020 20:01:00 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 6E66B208C4 for ; Fri, 21 Feb 2020 20:01:00 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6E66B208C4 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=kerneltoast.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 2278C6B0003; Fri, 21 Feb 2020 15:01:00 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 1D8506B0006; Fri, 21 Feb 2020 15:01:00 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 1150A6B0007; Fri, 21 Feb 2020 15:01:00 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0174.hostedemail.com [216.40.44.174]) by kanga.kvack.org (Postfix) with ESMTP id EAE7E6B0003 for ; Fri, 21 Feb 2020 15:00:59 -0500 (EST) Received: from smtpin22.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 9D62C181AEF10 for ; Fri, 21 Feb 2020 20:00:59 +0000 (UTC) X-FDA: 76515202638.22.time57_25bc3e8eaaf63 X-HE-Tag: time57_25bc3e8eaaf63 X-Filterd-Recvd-Size: 3617 Received: from mail-pg1-f196.google.com (mail-pg1-f196.google.com [209.85.215.196]) by imf14.hostedemail.com (Postfix) with ESMTP for ; Fri, 21 Feb 2020 20:00:59 +0000 (UTC) Received: by mail-pg1-f196.google.com with SMTP id d6so1522244pgn.5 for ; Fri, 21 Feb 2020 12:00:59 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=pNlnTirvfiB7WYuVJDwmUBab2nwnkqDGWJI3ppaa8x4=; b=nKP0/LAiVaKMNzVu88WfpnFbkNUdY/Lk5yv5KMu16PfpX82gsW3sZwxmKg5C9omxvm Pn7mUj2IWvpuJb3e3q8s/Pp/g9dDxksFj3S+o4Q0QWO1Ehzlx6NafseIibtet+NFO2KS qFb7sWl37HwO5YGYaxRIxAt/39TfvkOJpOHVmf+NRXSelTK2m+T1eVDr3WTg7GITZ5wZ 1fhtJqJFj3jkYkJ1Z2jWRvkK00YbiLkGqF0p8RVfVOcu/CiM/0QSAJDcFJ9gYSb+JyRZ RxHIqdNCp12iRGJ9OgMqeUDmUyFK/zlhPWyyu5JjpfGSDPDnKObH0fR2HziAc4SCh31u 1JQg== X-Gm-Message-State: APjAAAVOZgQxt5x6t30/w6lS4xnJAO5mXMmiFGdtpIz5JOSYsTEawIJH eRQQ3DCsEiF5KjM64/gNyoY= X-Google-Smtp-Source: APXvYqyDH+RnreMq6IQELcDHf3TG+giHPDTLYj++X9i8qmnDj85M589gPmQyJC0Wr3jodkDVJucX1w== X-Received: by 2002:aa7:9aa7:: with SMTP id x7mr37599786pfi.78.1582315257906; Fri, 21 Feb 2020 12:00:57 -0800 (PST) Received: from sultan-book.localdomain ([2620:15c:f:fd00:d989:fbb1:a399:c92d]) by smtp.gmail.com with ESMTPSA id g7sm3853756pfq.33.2020.02.21.12.00.56 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 21 Feb 2020 12:00:57 -0800 (PST) Date: Fri, 21 Feb 2020 12:00:54 -0800 From: Sultan Alsawaf To: Ira Weiny Cc: Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2] mm: Stop kswapd early when nothing's waiting for it to free pages Message-ID: <20200221200054.GA3851@sultan-book.localdomain> References: <20200219182522.1960-1-sultan@kerneltoast.com> <20200221043052.3305-1-sultan@kerneltoast.com> <20200221182201.GB4462@iweiny-DESK2.sc.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200221182201.GB4462@iweiny-DESK2.sc.intel.com> X-Bogosity: Ham, tests=bogofilter, spamicity=0.005649, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Fri, Feb 21, 2020 at 10:22:02AM -0800, Ira Weiny wrote: > On Thu, Feb 20, 2020 at 08:30:52PM -0800, Sultan Alsawaf wrote: > > From: Sultan Alsawaf > > [snip] > > > @@ -4640,9 +4647,12 @@ __alloc_pages_slowpath(gfp_t gfp_mask, unsigned int order, > > goto retry; > > } > > fail: > > - warn_alloc(gfp_mask, ac->nodemask, > > - "page allocation failure: order:%u", order); > > got_pg: > > I have no insight into if this is masking a deeper problem or if this fixes > something but doesn't the above result in 'fail' and 'got_pg' being the same > label? > > Ira > > > + if (woke_kswapd) > > + atomic_dec(&pgdat->kswapd_waiters); > > + if (!page) > > + warn_alloc(gfp_mask, ac->nodemask, > > + "page allocation failure: order:%u", order); > > return page; > > } > > [snip] Yes,. This was to reduce the patch delta for the initial submission so it's clearer what's going on; it can be altered of course to coalesce the labels into a single one. I typically produce my patches to upstream components to be as uninvasive as possible to aid in backporting and forward porting in case it's rejected and I want to keep it for myself. Sultan