From patchwork Sun May 12 16:09:26 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Shakeel Butt X-Patchwork-Id: 10940077 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id DEF21112C for ; Sun, 12 May 2019 16:09:48 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id D004D2624B for ; Sun, 12 May 2019 16:09:48 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id C3D33268AE; Sun, 12 May 2019 16:09:48 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.5 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI, USER_IN_DEF_DKIM_WL autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 723BB2624B for ; Sun, 12 May 2019 16:09:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726669AbfELQJm (ORCPT ); Sun, 12 May 2019 12:09:42 -0400 Received: from mail-vk1-f202.google.com ([209.85.221.202]:47669 "EHLO mail-vk1-f202.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726529AbfELQJm (ORCPT ); Sun, 12 May 2019 12:09:42 -0400 Received: by mail-vk1-f202.google.com with SMTP id x77so5312216vke.14 for ; Sun, 12 May 2019 09:09:42 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:message-id:mime-version:subject:from:to:cc; bh=ZQi/sjipIMJL03RXDXGUBdRsbi1X2/+nI6E1TTfR44o=; b=rT6GYZe9JljSs+O2RaDoCdYaRjz42r+UWesVjP61KLuG6brTai+B8I0s6wONcIdeUT ZgBS6h91WxDWjJLdDl7mdy4nSk0wB5tEBBSyUohFeLAeQOweZF4nSJgoeSX+Z5lOzW7w w1Kh4U5cruF03Fr6NcBIc2mu420URojoYNetRwXEgPNIIXNvzdCfMX4cuXwBaod2hE8y AcVWU+jdpmBSZ75RVzArG/oirAEeyO6gh8KNjZ7rVUrwOjObNx6lGpqFGYsn7BWv0Bz4 yPD+2/26OCSf5xX0lvA/2dklhzgpKqeKHWI2sajCsyjGu0mYRjb04/FHoNtrsslXB/MH Fe+A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:message-id:mime-version:subject:from:to:cc; bh=ZQi/sjipIMJL03RXDXGUBdRsbi1X2/+nI6E1TTfR44o=; b=EDfSmXsFGCwmg7EFMJHmuLrVZme78WJDZ4b66eC9mygScWDbJcWFX6f2rzMYsXIQKo k0zqbXhGAugwEP7npiUpHgt5Ql7AI5pZAi0dtakO8fxeI31CnATo0Hr/kVz/qQSr2V/q UOT78q0uokPbEkgnsoP5XMPV9fUgN2TCqNnVKmUDAQXsA39li4I/nyA5PcSRw5TXCUNa g32VzpRFvJ/Ngv/rI32qf3WXEiPFmyUo0jag8ydUTCNUk+w9QCzN19J1fUSyq70MtvXv ULIZSDLQ2teQO4cxR1eBEpKTc8czh948uk4cw/vb7GWi6KHgj5AdxdiRcmnrPcLPOLx7 cJzA== X-Gm-Message-State: APjAAAWBNhKAHhce2FKiePEDqmMJJ8JzHE3b+FS0GNLO0O0/0qUSif1D bGFiZj5jWMmLCQ8Idpu5ch5+qhFTArJnEg== X-Google-Smtp-Source: APXvYqzwH4rxmIbxD+iMOiqD9UQKKFw9tWXDR5aDKuxRx6lP62JMAnkQ546tt3tD+hmPNt6X3Uoy8PlTi8nDoA== X-Received: by 2002:a67:dd0c:: with SMTP id y12mr1988351vsj.119.1557677381452; Sun, 12 May 2019 09:09:41 -0700 (PDT) Date: Sun, 12 May 2019 09:09:26 -0700 Message-Id: <20190512160927.80042-1-shakeelb@google.com> Mime-Version: 1.0 X-Mailer: git-send-email 2.21.0.1020.gf2820cf01a-goog Subject: [RESEND PATCH v2 1/2] memcg, oom: no oom-kill for __GFP_RETRY_MAYFAIL From: Shakeel Butt To: Johannes Weiner , Vladimir Davydov , Michal Hocko , Andrew Morton , Roman Gushchin , Jan Kara , Amir Goldstein Cc: linux-mm@kvack.org, cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, Shakeel Butt Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP The documentation of __GFP_RETRY_MAYFAIL clearly mentioned that the OOM killer will not be triggered and indeed the page alloc does not invoke OOM killer for such allocations. However we do trigger memcg OOM killer for __GFP_RETRY_MAYFAIL. Fix that. This flag will used later to not trigger oom-killer in the charging path for fanotify and inotify event allocations. Signed-off-by: Shakeel Butt Acked-by: Michal Hocko --- Changelog since v1: - commit message updated. mm/memcontrol.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 2535e54e7989..9548dfcae432 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -2294,7 +2294,6 @@ static int try_charge(struct mem_cgroup *memcg, gfp_t gfp_mask, unsigned long nr_reclaimed; bool may_swap = true; bool drained = false; - bool oomed = false; enum oom_status oom_status; if (mem_cgroup_is_root(memcg)) @@ -2381,7 +2380,7 @@ static int try_charge(struct mem_cgroup *memcg, gfp_t gfp_mask, if (nr_retries--) goto retry; - if (gfp_mask & __GFP_RETRY_MAYFAIL && oomed) + if (gfp_mask & __GFP_RETRY_MAYFAIL) goto nomem; if (gfp_mask & __GFP_NOFAIL) @@ -2400,7 +2399,6 @@ static int try_charge(struct mem_cgroup *memcg, gfp_t gfp_mask, switch (oom_status) { case OOM_SUCCESS: nr_retries = MEM_CGROUP_RECLAIM_RETRIES; - oomed = true; goto retry; case OOM_FAILED: goto force; From patchwork Sun May 12 16:09:27 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Shakeel Butt X-Patchwork-Id: 10940081 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 3CA55112C for ; Sun, 12 May 2019 16:10:04 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 29C351FF13 for ; Sun, 12 May 2019 16:10:04 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 19295201CB; Sun, 12 May 2019 16:10:04 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.5 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI, USER_IN_DEF_DKIM_WL autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id AC4E51FF13 for ; Sun, 12 May 2019 16:10:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726799AbfELQJ6 (ORCPT ); Sun, 12 May 2019 12:09:58 -0400 Received: from mail-yw1-f74.google.com ([209.85.161.74]:48572 "EHLO mail-yw1-f74.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726553AbfELQJ5 (ORCPT ); Sun, 12 May 2019 12:09:57 -0400 Received: by mail-yw1-f74.google.com with SMTP id q188so20524845ywc.15 for ; Sun, 12 May 2019 09:09:57 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=pNYDYF29KQTiDsLTir5ePdeguGYagzUQEsurF8lSHbY=; b=i3YEIaQIHO/PR2+mMIFIpaGHrsGtdYQBTKhgEeVGdXy6IjrQUWW5WGYFsXSjxoy4Qa 5xlboHTgv9cyDLZ9V2BO/jEBAklDBwaVlu3TrXjcaV9JkSH4r/P/p1LzRbEzXM8NGGqh aRossIettQVPYRP2lRDcOH67U+qYdSZGyj8FX4IOWj8uCAckk7xaZVr5GB9pAj4t4hz5 tsXRN5yNqBGxFb7yJ9dJbrVjuLxoYHIHNy5JGiw3cCLlaZQjNXt/bf4IpwEQgLEKf8BV SFS4JqfbN/IHML9PTuVHjyceb1Le0/n+fA3YtuBOVoJ7+b6QgRQjGdnyBJBvvSOkAeon Uifw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=pNYDYF29KQTiDsLTir5ePdeguGYagzUQEsurF8lSHbY=; b=thfbFI0pEuMeVpN+CdUfoA7nCczB2c1JMf4zf4DqC4ljRe3brcB/ZnfQkWfmzHnk5L zf4tkgBSyCXL62YtVbyDq40xtPS3Z/L6ZaTgZOeUi19w9jRLvGp+oOJKMm3liYJ9gc0A MW68KD6ctdcQE2scVRp7P8H9qXraPKrYml9zDZgKa6lJYHjE/UCG7c7nkD/rrO8LDYjp s+gA+NHTF1D4AGyqLiXyD4zKsQN6qOha20cJJ8248AMNMLOmKgc1HvttNxG7rv4dVuRy ck1C/xLVEPYMOctoQ18i+LRhDBKfVEBV2cAcdjLpcOnHjBxXXS0MphR//rvyVhdgYnrO UbTg== X-Gm-Message-State: APjAAAXcyXZuDTRchMJss9OlD06SGrXv6tUoClGnreNYxx4DdasIfRhf cDavieTL4vcgM/b3TVlok1DwUD2pqKCdmg== X-Google-Smtp-Source: APXvYqwFjUEgIaKr0kbwdw7yEWcBwWFgnrXBu4fdjexDy0pGsGSbQmVSEDWFzUFaVoq6HIRtK7D5ckxThWerQA== X-Received: by 2002:a25:585:: with SMTP id 127mr10890358ybf.60.1557677396951; Sun, 12 May 2019 09:09:56 -0700 (PDT) Date: Sun, 12 May 2019 09:09:27 -0700 In-Reply-To: <20190512160927.80042-1-shakeelb@google.com> Message-Id: <20190512160927.80042-2-shakeelb@google.com> Mime-Version: 1.0 References: <20190512160927.80042-1-shakeelb@google.com> X-Mailer: git-send-email 2.21.0.1020.gf2820cf01a-goog Subject: [RESEND PATCH v2 2/2] memcg, fsnotify: no oom-kill for remote memcg charging From: Shakeel Butt To: Johannes Weiner , Vladimir Davydov , Michal Hocko , Andrew Morton , Roman Gushchin , Jan Kara , Amir Goldstein Cc: linux-mm@kvack.org, cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, Shakeel Butt Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP The commit d46eb14b735b ("fs: fsnotify: account fsnotify metadata to kmemcg") added remote memcg charging for fanotify and inotify event objects. The aim was to charge the memory to the listener who is interested in the events but without triggering the OOM killer. Otherwise there would be security concerns for the listener. At the time, oom-kill trigger was not in the charging path. A parallel work added the oom-kill back to charging path i.e. commit 29ef680ae7c2 ("memcg, oom: move out_of_memory back to the charge path"). So to not trigger oom-killer in the remote memcg, explicitly add __GFP_RETRY_MAYFAIL to the fanotigy and inotify event allocations. Signed-off-by: Shakeel Butt Reviewed-by: Roman Gushchin --- Changelog since v1: - Fixed usage of __GFP_RETRY_MAYFAIL flag. fs/notify/fanotify/fanotify.c | 5 ++++- fs/notify/inotify/inotify_fsnotify.c | 7 +++++-- 2 files changed, 9 insertions(+), 3 deletions(-) diff --git a/fs/notify/fanotify/fanotify.c b/fs/notify/fanotify/fanotify.c index 6b9c27548997..f78fd4c8f12d 100644 --- a/fs/notify/fanotify/fanotify.c +++ b/fs/notify/fanotify/fanotify.c @@ -288,10 +288,13 @@ struct fanotify_event *fanotify_alloc_event(struct fsnotify_group *group, /* * For queues with unlimited length lost events are not expected and * can possibly have security implications. Avoid losing events when - * memory is short. + * memory is short. Also make sure to not trigger OOM killer in the + * target memcg for the limited size queues. */ if (group->max_events == UINT_MAX) gfp |= __GFP_NOFAIL; + else + gfp |= __GFP_RETRY_MAYFAIL; /* Whoever is interested in the event, pays for the allocation. */ memalloc_use_memcg(group->memcg); diff --git a/fs/notify/inotify/inotify_fsnotify.c b/fs/notify/inotify/inotify_fsnotify.c index ff30abd6a49b..17c08daa1ba7 100644 --- a/fs/notify/inotify/inotify_fsnotify.c +++ b/fs/notify/inotify/inotify_fsnotify.c @@ -99,9 +99,12 @@ int inotify_handle_event(struct fsnotify_group *group, i_mark = container_of(inode_mark, struct inotify_inode_mark, fsn_mark); - /* Whoever is interested in the event, pays for the allocation. */ + /* + * Whoever is interested in the event, pays for the allocation. However + * do not trigger the OOM killer in the target memcg. + */ memalloc_use_memcg(group->memcg); - event = kmalloc(alloc_len, GFP_KERNEL_ACCOUNT); + event = kmalloc(alloc_len, GFP_KERNEL_ACCOUNT | __GFP_RETRY_MAYFAIL); memalloc_unuse_memcg(); if (unlikely(!event)) {