From patchwork Thu Jul 12 17:29:35 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Johannes Weiner X-Patchwork-Id: 10522031 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id A07FE602C8 for ; Thu, 12 Jul 2018 17:27:40 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 7755E29AC1 for ; Thu, 12 Jul 2018 17:27:40 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 688A429AD2; Thu, 12 Jul 2018 17:27:40 +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=-2.8 required=2.0 tests=BAYES_00,DKIM_SIGNED, MAILING_LIST_MULTI,RCVD_IN_DNSWL_NONE,T_DKIM_INVALID autolearn=ham version=3.3.1 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id A338529AC1 for ; Thu, 12 Jul 2018 17:27:39 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 3345D6B0008; Thu, 12 Jul 2018 13:27:33 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id 2E6ED6B0269; Thu, 12 Jul 2018 13:27:33 -0400 (EDT) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 0E2DB6B026A; Thu, 12 Jul 2018 13:27:33 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from mail-ed1-f69.google.com (mail-ed1-f69.google.com [209.85.208.69]) by kanga.kvack.org (Postfix) with ESMTP id A048E6B0008 for ; Thu, 12 Jul 2018 13:27:32 -0400 (EDT) Received: by mail-ed1-f69.google.com with SMTP id p5-v6so3146195edh.16 for ; Thu, 12 Jul 2018 10:27:32 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:dkim-signature:from:to:cc:subject:date :message-id:in-reply-to:references; bh=yu9UdCtaoT51hJzI6OxnWMzNlhzbw5nOYEshpoGdmog=; b=LXPRA8pu/TgyVOHQWxmXZaspXIv19AbO6rFkSGa19M1839uAT+/t8oMy66IGYlleLN jP0TP1gq7KiTTPJWgXf5kEBZtIuUGXmsMH0a3bj5GWvcUuZso9AUieh9mHoesJF/tYJD vYPDIKfbsB4o09SChAF4+2IYbhW8mWu+UP0LTEjFAbIGBkiVI0NQkxPCQDU8+iybUcrT UQUMwzCxI14JnILCyRF1E7XHjEszZs3XQcSPnBLZXmCyVVyveAJIddEs7ysW4JRVgi7J QnhV+PxyezBVRzIvimDqkmYktuxqcoO0FZNFy0uCBCut9V9ptBie7sfNuvDVQQKW0V5K 755A== X-Gm-Message-State: AOUpUlHggjfYh9KIItPiL0rG3vz7EOTEdRk79CeEcqt4n744EiZgC4z+ ZDbrseLV4AVO2yu4F8Jw9TmC8cbFSkT1ntLPh3VTkEn1wUgRwbk/9pRMjQjY9wASX3qIYAqSABT K5epzKhRluaSee7xq19AMt5ST0jfNtneuobIFjFlbVpZYXLklVXVJtlOU13CK88jXyg== X-Received: by 2002:a50:aec9:: with SMTP id f9-v6mr3538918edd.72.1531416452215; Thu, 12 Jul 2018 10:27:32 -0700 (PDT) X-Google-Smtp-Source: AAOMgpcNJx6CVWzaksMq4dWjjFAggulje5aPJkCTFHuQn8QtLXeArjnr+ioIkEl7QK9TVBZj0ybJ X-Received: by 2002:a50:aec9:: with SMTP id f9-v6mr3538870edd.72.1531416451299; Thu, 12 Jul 2018 10:27:31 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1531416451; cv=none; d=google.com; s=arc-20160816; b=U8uKfwZda/wb9Sftx8j1iyRX8Q0GDcIrVS0/4mlWdN8uxSWjMqDOdcDvYNpx6MYdTy NJxX85dINo+ztrIFfP7xNB8Yv+Nn5SrEmkWTQRcuIQp1L721X3wi12C4m2w7F9jHZRiI xcdzRiYywXPfJClZqnJeW1mbh1HK8jC5pATT2WNGucDG/cv7Wxh5ugrCuvHxjrsb7214 4huFSPK7JPtVuFCPspLVLkkh8HhLS5+TvJsfAGZpRRJ65Pc4EjZZqV5ePnV0gNyWwUFU JqeoDsUznZBOdnlItswZz033jFF2gZs7szcjJWH01ucJ+waigB8d/FuWz5X3eqsCRd+X g6Og== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=references:in-reply-to:message-id:date:subject:cc:to:from :dkim-signature:arc-authentication-results; bh=yu9UdCtaoT51hJzI6OxnWMzNlhzbw5nOYEshpoGdmog=; b=n2SQB71m2AQV3nbVQspxITgtnNJyM2/6ZvMQSijKW2hbrFHBsda/pdRZCnLWjAZMT9 sa4ltRBkO+ffkGJSmZq4RolC5miIM6J9r/uxIng95Le4hDmmH8royWk7eXVGxKjYSZiV wH2szzha6HmVcSRkoTvm+yXadJilLvMczZqODpqEHDj3fT4fv9+bV4t+3uO6T4DmVxR9 nyMHkxEgG/xPh+VsVlSoL1tDX8sUO/nOJo2leOacfOLE5Q86vNYDuDPW5ZedUSnUDjhe wCrgdvXI0E49+VZ1sRXDfGoLz5T97S+KPUg3VQEU1khqoQjww77TPj9MWp+pdZI6Xxwp 8DDw== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@cmpxchg.org header.s=x header.b=zA0usnXN; spf=pass (google.com: domain of hannes@cmpxchg.org designates 85.214.110.215 as permitted sender) smtp.mailfrom=hannes@cmpxchg.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=cmpxchg.org Received: from gum.cmpxchg.org (gum.cmpxchg.org. [85.214.110.215]) by mx.google.com with ESMTPS id o11-v6si2725930edi.441.2018.07.12.10.27.31 for (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Thu, 12 Jul 2018 10:27:31 -0700 (PDT) Received-SPF: pass (google.com: domain of hannes@cmpxchg.org designates 85.214.110.215 as permitted sender) client-ip=85.214.110.215; Authentication-Results: mx.google.com; dkim=pass header.i=@cmpxchg.org header.s=x header.b=zA0usnXN; spf=pass (google.com: domain of hannes@cmpxchg.org designates 85.214.110.215 as permitted sender) smtp.mailfrom=hannes@cmpxchg.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=cmpxchg.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=cmpxchg.org ; s=x; h=References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender: Reply-To:MIME-Version:Content-Type:Content-Transfer-Encoding:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Id:List-Help:List-Unsubscribe:List-Subscribe: List-Post:List-Owner:List-Archive; bh=yu9UdCtaoT51hJzI6OxnWMzNlhzbw5nOYEshpoGdmog=; b=zA0usnXNQO14f41mcFKA/5hBKq 59brfcF1EU9IYfDckTDAlvqZqEX9Gt3K3D1AjKiisXFfeVGKO2RYut7aI+w1rVBGXqFGBwLWiE9qs g0LIC2rgfK3jv0GPYpGPf4paxhXLSFG7gNtMEUYYFC2OOQiNXnrECMNTRlmUvVclJEnc=; From: Johannes Weiner To: Ingo Molnar , Peter Zijlstra , Andrew Morton , Linus Torvalds Cc: Tejun Heo , Suren Baghdasaryan , Vinayak Menon , Christopher Lameter , Mike Galbraith , Shakeel Butt , linux-mm@kvack.org, cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-team@fb.com Subject: [PATCH 03/10] delayacct: track delays from thrashing cache pages Date: Thu, 12 Jul 2018 13:29:35 -0400 Message-Id: <20180712172942.10094-4-hannes@cmpxchg.org> X-Mailer: git-send-email 2.18.0 In-Reply-To: <20180712172942.10094-1-hannes@cmpxchg.org> References: <20180712172942.10094-1-hannes@cmpxchg.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: X-Virus-Scanned: ClamAV using ClamSMTP Delay accounting already measures the time a task spends in direct reclaim and waiting for swapin, but in low memory situations tasks spend can spend a significant amount of their time waiting on thrashing page cache. This isn't tracked right now. To know the full impact of memory contention on an individual task, measure the delay when waiting for a recently evicted active cache page to read back into memory. Also update tools/accounting/getdelays.c: [hannes@computer accounting]$ sudo ./getdelays -d -p 1 print delayacct stats ON PID 1 CPU count real total virtual total delay total delay average 50318 745000000 847346785 400533713 0.008ms IO count delay total delay average 435 122601218 0ms SWAP count delay total delay average 0 0 0ms RECLAIM count delay total delay average 0 0 0ms THRASHING count delay total delay average 19 12621439 0ms Signed-off-by: Johannes Weiner --- include/linux/delayacct.h | 23 +++++++++++++++++++++++ include/uapi/linux/taskstats.h | 6 +++++- kernel/delayacct.c | 15 +++++++++++++++ mm/filemap.c | 11 +++++++++++ tools/accounting/getdelays.c | 8 +++++++- 5 files changed, 61 insertions(+), 2 deletions(-) diff --git a/include/linux/delayacct.h b/include/linux/delayacct.h index 5e335b6203f4..d3e75b3ba487 100644 --- a/include/linux/delayacct.h +++ b/include/linux/delayacct.h @@ -57,7 +57,12 @@ struct task_delay_info { u64 freepages_start; u64 freepages_delay; /* wait for memory reclaim */ + + u64 thrashing_start; + u64 thrashing_delay; /* wait for thrashing page */ + u32 freepages_count; /* total count of memory reclaim */ + u32 thrashing_count; /* total count of thrash waits */ }; #endif @@ -76,6 +81,8 @@ extern int __delayacct_add_tsk(struct taskstats *, struct task_struct *); extern __u64 __delayacct_blkio_ticks(struct task_struct *); extern void __delayacct_freepages_start(void); extern void __delayacct_freepages_end(void); +extern void __delayacct_thrashing_start(void); +extern void __delayacct_thrashing_end(void); static inline int delayacct_is_task_waiting_on_io(struct task_struct *p) { @@ -156,6 +163,18 @@ static inline void delayacct_freepages_end(void) __delayacct_freepages_end(); } +static inline void delayacct_thrashing_start(void) +{ + if (current->delays) + __delayacct_thrashing_start(); +} + +static inline void delayacct_thrashing_end(void) +{ + if (current->delays) + __delayacct_thrashing_end(); +} + #else static inline void delayacct_set_flag(int flag) {} @@ -182,6 +201,10 @@ static inline void delayacct_freepages_start(void) {} static inline void delayacct_freepages_end(void) {} +static inline void delayacct_thrashing_start(void) +{} +static inline void delayacct_thrashing_end(void) +{} #endif /* CONFIG_TASK_DELAY_ACCT */ diff --git a/include/uapi/linux/taskstats.h b/include/uapi/linux/taskstats.h index b7aa7bb2349f..5e8ca16a9079 100644 --- a/include/uapi/linux/taskstats.h +++ b/include/uapi/linux/taskstats.h @@ -34,7 +34,7 @@ */ -#define TASKSTATS_VERSION 8 +#define TASKSTATS_VERSION 9 #define TS_COMM_LEN 32 /* should be >= TASK_COMM_LEN * in linux/sched.h */ @@ -164,6 +164,10 @@ struct taskstats { /* Delay waiting for memory reclaim */ __u64 freepages_count; __u64 freepages_delay_total; + + /* Delay waiting for thrashing page */ + __u64 thrashing_count; + __u64 thrashing_delay_total; }; diff --git a/kernel/delayacct.c b/kernel/delayacct.c index e2764d767f18..02ba745c448d 100644 --- a/kernel/delayacct.c +++ b/kernel/delayacct.c @@ -134,9 +134,12 @@ int __delayacct_add_tsk(struct taskstats *d, struct task_struct *tsk) d->swapin_delay_total = (tmp < d->swapin_delay_total) ? 0 : tmp; tmp = d->freepages_delay_total + tsk->delays->freepages_delay; d->freepages_delay_total = (tmp < d->freepages_delay_total) ? 0 : tmp; + tmp = d->thrashing_delay_total + tsk->delays->thrashing_delay; + d->thrashing_delay_total = (tmp < d->thrashing_delay_total) ? 0 : tmp; d->blkio_count += tsk->delays->blkio_count; d->swapin_count += tsk->delays->swapin_count; d->freepages_count += tsk->delays->freepages_count; + d->thrashing_count += tsk->delays->thrashing_count; spin_unlock_irqrestore(&tsk->delays->lock, flags); return 0; @@ -168,3 +171,15 @@ void __delayacct_freepages_end(void) ¤t->delays->freepages_count); } +void __delayacct_thrashing_start(void) +{ + current->delays->thrashing_start = ktime_get_ns(); +} + +void __delayacct_thrashing_end(void) +{ + delayacct_end(¤t->delays->lock, + ¤t->delays->thrashing_start, + ¤t->delays->thrashing_delay, + ¤t->delays->thrashing_count); +} diff --git a/mm/filemap.c b/mm/filemap.c index bd36b7226cf4..e49961e13dd9 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -36,6 +36,7 @@ #include #include #include +#include #include "internal.h" #define CREATE_TRACE_POINTS @@ -1073,8 +1074,15 @@ static inline int wait_on_page_bit_common(wait_queue_head_t *q, { struct wait_page_queue wait_page; wait_queue_entry_t *wait = &wait_page.wait; + bool thrashing = false; int ret = 0; + if (bit_nr == PG_locked && !PageSwapBacked(page) && + !PageUptodate(page) && PageWorkingset(page)) { + delayacct_thrashing_start(); + thrashing = true; + } + init_wait(wait); wait->flags = lock ? WQ_FLAG_EXCLUSIVE : 0; wait->func = wake_page_function; @@ -1113,6 +1121,9 @@ static inline int wait_on_page_bit_common(wait_queue_head_t *q, finish_wait(q, wait); + if (thrashing) + delayacct_thrashing_end(); + /* * A signal could leave PageWaiters set. Clearing it here if * !waitqueue_active would be possible (by open-coding finish_wait), diff --git a/tools/accounting/getdelays.c b/tools/accounting/getdelays.c index 9f420d98b5fb..8cb504d30384 100644 --- a/tools/accounting/getdelays.c +++ b/tools/accounting/getdelays.c @@ -203,6 +203,8 @@ static void print_delayacct(struct taskstats *t) "SWAP %15s%15s%15s\n" " %15llu%15llu%15llums\n" "RECLAIM %12s%15s%15s\n" + " %15llu%15llu%15llums\n" + "THRASHING%12s%15s%15s\n" " %15llu%15llu%15llums\n", "count", "real total", "virtual total", "delay total", "delay average", @@ -222,7 +224,11 @@ static void print_delayacct(struct taskstats *t) "count", "delay total", "delay average", (unsigned long long)t->freepages_count, (unsigned long long)t->freepages_delay_total, - average_ms(t->freepages_delay_total, t->freepages_count)); + average_ms(t->freepages_delay_total, t->freepages_count), + "count", "delay total", "delay average", + (unsigned long long)t->thrashing_count, + (unsigned long long)t->thrashing_delay_total, + average_ms(t->thrashing_delay_total, t->thrashing_count)); } static void task_context_switch_counts(struct taskstats *t)