From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Cyrus-Session-Id: sloti22d1t05-158926-1521910335-3-3295577391794853059 X-Sieve: CMU Sieve 3.0 X-Spam-known-sender: no X-Spam-score: 0.0 X-Spam-hits: BAYES_00 -1.9, RCVD_IN_DNSWL_HI -5, T_RP_MATCHES_RCVD -0.01, LANGUAGES en, BAYES_USED global, SA_VERSION 3.4.0 X-Spam-source: IP='209.132.180.67', Host='vger.kernel.org', Country='CN', FromHeader='org', MailFrom='org' X-Spam-charsets: X-Resolved-to: greg@kroah.com X-Delivered-to: greg@kroah.com X-Mail-from: linux-api-owner@vger.kernel.org ARC-Seal: i=1; a=rsa-sha256; cv=none; d=messagingengine.com; s=arctest; t=1521910334; b=QG6lsUyGePl7myqK+4bKFmZDd2AMnzgUps3oeyDOySFAbDx qXG+xtWIJMxPU0oK1aqG4bRvIuLC1n2JbTIwSXgO1fzsTht4U8ToI9uBCtKhOmzS WPeX4pznSA3L1kDdUmIfwxPTCUYNWWfH/SNRfQX7Ys02HXt+1cYx5/GnihD8xcMY q297euzH8tJHij5QPZJ5lJTHWBI7Erd37uQ6Mn35vDpsV+wnh5nD/RJa4GSElVY3 fZaxAuIxChVvxFAWlMMo/WgU/4hmk7TyJDvarx4Lf6Iw2AJ4/nEuaV9r3jDQYRD0 y4iXT73saiRJNG3pE71tKYNVc+0p4xsxBNHTVPw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=from:to:cc:subject:date:message-id :in-reply-to:references:sender:list-id; s=arctest; t=1521910334; bh=F2dszFmORTEWNhhPQ9tFklvEM4H+/rrWKxYCx32wkn0=; b=aut3j98+zAOS Bdk+E6sOBPcQM7E2VNfIDy2DaBkpGp0eyr3ejOWcAzeU+cHg9ti7peDCXCqiXFLw 9XdLl3FAswRXOn7ar0mCoFghV0QEAKcg5zQuoZUabvUe9b2KIILi692Z4tXUIvW+ IC6nhwLmHtkJ1VWhaTZH04uaZSGeJ92G2h+NKuo43tL2bAyodihoCDCYrvPRSiJ8 M6oItymBphvq84jcTut7XVP5rMZGh4ehV8vZzpn3EKSoaKF90XwIpdVlhQG8M8MX uSNLv84QGUyY96ghESmjrCsMUOcTBXUZ4Wz5k4oF+x77ZTe9WSSsMAZ6lt1lX1iA RX9k6lYyLA== ARC-Authentication-Results: i=1; mx5.messagingengine.com; arc=none (no signatures found); dkim=fail (message has been altered, 2048-bit rsa key sha256) header.d=gmail.com header.i=@gmail.com header.b=r2QsDjcm x-bits=2048 x-keytype=rsa x-algorithm=sha256 x-selector=20161025; dmarc=none (p=none,has-list-id=yes,d=none) header.from=kernel.org; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=linux-api-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=orgdomain_pass (Domain org match); x-google-dkim=fail (message has been altered, 2048-bit rsa key) header.d=1e100.net header.i=@1e100.net header.b=aqbZ2I8/; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=kernel.org header.result=pass header_is_org_domain=yes; x-vs=clean score=0 state=0 Authentication-Results: mx5.messagingengine.com; arc=none (no signatures found); dkim=fail (message has been altered, 2048-bit rsa key sha256) header.d=gmail.com header.i=@gmail.com header.b=r2QsDjcm x-bits=2048 x-keytype=rsa x-algorithm=sha256 x-selector=20161025; dmarc=none (p=none,has-list-id=yes,d=none) header.from=kernel.org; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=linux-api-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=orgdomain_pass (Domain org match); x-google-dkim=fail (message has been altered, 2048-bit rsa key) header.d=1e100.net header.i=@1e100.net header.b=aqbZ2I8/; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=kernel.org header.result=pass header_is_org_domain=yes; x-vs=clean score=0 state=0 X-ME-VSCategory: clean Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752618AbeCXQwA (ORCPT ); Sat, 24 Mar 2018 12:52:00 -0400 Received: from mail-yb0-f196.google.com ([209.85.213.196]:36492 "EHLO mail-yb0-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752593AbeCXQvq (ORCPT ); Sat, 24 Mar 2018 12:51:46 -0400 X-Google-Smtp-Source: AIpwx4+TtC4mrWSjwEocvBDicoEonLnOikZy7a+40PlZ4wsPHBO7MjDNNXiL1WSgebPFAhraWo7k+Q== From: Tejun Heo To: hannes@cmpxchg.org, mhocko@kernel.org, vdavydov.dev@gmail.com Cc: guro@fb.com, riel@surriel.com, akpm@linux-foundation.org, linux-kernel@vger.kernel.org, kernel-team@fb.com, cgroups@vger.kernel.org, linux-mm@kvack.org, Tejun Heo , linux-api@vger.kernel.org Subject: [PATCH 2/2] mm, memcontrol: Implement memory.swap.events Date: Sat, 24 Mar 2018 09:51:27 -0700 Message-Id: <20180324165127.701194-3-tj@kernel.org> X-Mailer: git-send-email 2.9.5 In-Reply-To: <20180324165127.701194-1-tj@kernel.org> References: <20180324165127.701194-1-tj@kernel.org> Sender: linux-api-owner@vger.kernel.org X-Mailing-List: linux-api@vger.kernel.org X-getmail-retrieved-from-mailbox: INBOX X-Mailing-List: linux-kernel@vger.kernel.org List-ID: Add swap max and fail events so that userland can monitor and respond to running out of swap. Signed-off-by: Tejun Heo Cc: Johannes Weiner Cc: Michal Hocko Cc: Vladimir Davydov Cc: Roman Gushchin Cc: Rik van Riel Cc: Andrew Morton Cc: linux-api@vger.kernel.org --- Documentation/cgroup-v2.txt | 16 ++++++++++++++++ include/linux/memcontrol.h | 5 +++++ mm/memcontrol.c | 24 +++++++++++++++++++++++- 3 files changed, 44 insertions(+), 1 deletion(-) diff --git a/Documentation/cgroup-v2.txt b/Documentation/cgroup-v2.txt index 74cdeae..b0dda10 100644 --- a/Documentation/cgroup-v2.txt +++ b/Documentation/cgroup-v2.txt @@ -1199,6 +1199,22 @@ PAGE_SIZE multiple when read back. Swap usage hard limit. If a cgroup's swap usage reaches this limit, anonymous memory of the cgroup will not be swapped out. + memory.swap.events + A read-only flat-keyed file which exists on non-root cgroups. + The following entries are defined. Unless specified + otherwise, a value change in this file generates a file + modified event. + + max + The number of times the cgroup's swap usage was about + to go over the max boundary and swap allocation + failed. + + fail + The number of times swap allocation failed either + because of running out of swap system-wide or max + limit. + Usage Guidelines ~~~~~~~~~~~~~~~~ diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index 85a8f00..f198339 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -54,6 +54,8 @@ enum memcg_event_item { MEMCG_HIGH, MEMCG_MAX, MEMCG_OOM, + MEMCG_SWAP_MAX, + MEMCG_SWAP_FAIL, MEMCG_NR_EVENTS, }; @@ -202,6 +204,9 @@ struct mem_cgroup { /* handle for "memory.events" */ struct cgroup_file events_file; + /* handle for "memory.swap.events" */ + struct cgroup_file swap_events_file; + /* protect arrays of thresholds */ struct mutex thresholds_lock; diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 9f9c8a7..1a14d4a4 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -5987,13 +5987,17 @@ int mem_cgroup_try_charge_swap(struct page *page, swp_entry_t entry) if (!memcg) return 0; - if (!entry.val) + if (!entry.val) { + mem_cgroup_event(memcg, MEMCG_SWAP_FAIL); return 0; + } memcg = mem_cgroup_id_get_online(memcg); if (!mem_cgroup_is_root(memcg) && !page_counter_try_charge(&memcg->swap, nr_pages, &counter)) { + mem_cgroup_event(memcg, MEMCG_SWAP_MAX); + mem_cgroup_event(memcg, MEMCG_SWAP_FAIL); mem_cgroup_id_put(memcg); return -ENOMEM; } @@ -6131,6 +6135,18 @@ static ssize_t swap_max_write(struct kernfs_open_file *of, return nbytes; } +static int swap_events_show(struct seq_file *m, void *v) +{ + struct mem_cgroup *memcg = mem_cgroup_from_css(seq_css(m)); + + memcg_stat_flush(memcg); + + seq_printf(m, "max %llu\n", memcg->events[MEMCG_SWAP_MAX]); + seq_printf(m, "fail %llu\n", memcg->events[MEMCG_SWAP_FAIL]); + + return 0; +} + static struct cftype swap_files[] = { { .name = "swap.current", @@ -6143,6 +6159,12 @@ static struct cftype swap_files[] = { .seq_show = swap_max_show, .write = swap_max_write, }, + { + .name = "swap.events", + .flags = CFTYPE_NOT_ON_ROOT, + .file_offset = offsetof(struct mem_cgroup, swap_events_file), + .seq_show = swap_events_show, + }, { } /* terminate */ }; -- 2.9.5