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=-1.0 required=3.0 tests=MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS 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 64033C10F27 for ; Wed, 11 Mar 2020 08:36:43 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 2E9E5208E4 for ; Wed, 11 Mar 2020 08:36:43 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2E9E5208E4 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id B6F646B0003; Wed, 11 Mar 2020 04:36:42 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id B20886B0006; Wed, 11 Mar 2020 04:36:42 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id A36A96B0007; Wed, 11 Mar 2020 04:36:42 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0041.hostedemail.com [216.40.44.41]) by kanga.kvack.org (Postfix) with ESMTP id 88F206B0003 for ; Wed, 11 Mar 2020 04:36:42 -0400 (EDT) Received: from smtpin30.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id 1BBBF812B for ; Wed, 11 Mar 2020 08:36:42 +0000 (UTC) X-FDA: 76582425444.30.land66_74af6de515840 X-HE-Tag: land66_74af6de515840 X-Filterd-Recvd-Size: 2931 Received: from mail-wr1-f43.google.com (mail-wr1-f43.google.com [209.85.221.43]) by imf16.hostedemail.com (Postfix) with ESMTP for ; Wed, 11 Mar 2020 08:36:41 +0000 (UTC) Received: by mail-wr1-f43.google.com with SMTP id v11so1397111wrm.9 for ; Wed, 11 Mar 2020 01:36:41 -0700 (PDT) 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=PrLRJuPbYIK7nmotXnXODJV5Yg8CVdNS7eXeA+2dkkE=; b=YSKrBh/1mSz1HJC1jiORNHaRMthCPD9/GtbKC76tSvMAvwY/HML3JILRZrUAjLlPrv Abak0NfwQLK8vL85swgumAfUq++kfdRBKinALALyKkcP0cKsTHupDAm8b7BzfOfSE04v bnoGsQ3eanFm0y4kGesWke+nUOYaC9x/S2ZGbc5xMuXe5dk2UQkOOpItIn3e7L+qZW0f xszmhp+p44TTmWTzIsDrwxSkNZjxuQHEHaBL5vL4iK5eMY0gqN2SjKScJ1YSD1Mm6hAg iQcirmgGZmHEiWZYUT6P/f+OBbqAsQmIQo1+5qT02sg7wueLTKgDkivBNVmA7M/W4bLK E2sA== X-Gm-Message-State: ANhLgQ2sjmjEyA6U7eOEL9JlX5b2g1NSGvrzocN9yaVM5tmvdIB+1alB njGm6v+7Elu6KTK7N8M8THo= X-Google-Smtp-Source: ADFU+vviEG7Xlq9OoItYp4ZTrXEdCMOzkHBwOCwILT8TQ8h+nJqJpS3kHQSO3J9buSMU9/7gAq0b6Q== X-Received: by 2002:adf:f047:: with SMTP id t7mr3277675wro.371.1583915800854; Wed, 11 Mar 2020 01:36:40 -0700 (PDT) Received: from localhost (prg-ext-pat.suse.com. [213.151.95.130]) by smtp.gmail.com with ESMTPSA id m11sm22952260wrn.92.2020.03.11.01.36.39 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 11 Mar 2020 01:36:40 -0700 (PDT) Date: Wed, 11 Mar 2020 09:36:39 +0100 From: Michal Hocko To: Andrew Morton Cc: David Rientjes , Vlastimil Babka , linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [patch] mm, oom: prevent soft lockup on memcg oom for UP systems Message-ID: <20200311083639.GB23944@dhcp22.suse.cz> References: <20200310171802.128129f6817ef3f77d230ccd@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200310171802.128129f6817ef3f77d230ccd@linux-foundation.org> 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: On Tue 10-03-20 17:18:02, Andrew Morton wrote: [...] > (And why is shrink_node_memcgs compiled in when CONFIG_MEMCG=n?) Because there won't be anything memcg specific with the config disabled. mem_cgroup_iter will expand to NULL memcg, mem_cgroup_protected switch compiled out, mem_cgroup_lruvec will return the lruvec abstraction which resolves to pgdat and the rest is not memcg dependent. We could have split up the reclaim protection or the loop out of the line but I believe it is better to be clearly visible. -- Michal Hocko SUSE Labs