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=-19.0 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham 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 26BC9C47084 for ; Tue, 25 May 2021 15:16:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0A2D661429 for ; Tue, 25 May 2021 15:16:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232335AbhEYPSU (ORCPT ); Tue, 25 May 2021 11:18:20 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58172 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232789AbhEYPRl (ORCPT ); Tue, 25 May 2021 11:17:41 -0400 Received: from mail-pg1-x52b.google.com (mail-pg1-x52b.google.com [IPv6:2607:f8b0:4864:20::52b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 15D7AC06138A for ; Tue, 25 May 2021 08:16:09 -0700 (PDT) Received: by mail-pg1-x52b.google.com with SMTP id q15so22980094pgg.12 for ; Tue, 25 May 2021 08:16:09 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=GlZpEK9HpCLX1XVPm0LSC4rLTUHCcfxj2n178z32Y0M=; b=mxAE3NfwZ9iFCmSb9LqnY+Hg5FJVex131Y+wRoKqcZ124YRsHEGuBnE8sdHNiyy7WV RCukxHD8R0fk6D7vDs2qzGyaMIZFu/trrMVFay62WXEQVmGfRxqOXj1DkxdLfHMRlWk2 K0CtqExsQoXwFGn4yjtDPrT1LV9xrQnKlwtY6qpwW4eG3uv9gKKB8T5HMEwdkPl6CPsc mHPFvlpbM/ZQQdMkiyCUGasOa3+xLJfY8cMugA3TsoYP3NcuvtYhDW0SJ2+dH8vz0AW5 8NK9w16HQYOxwV6POF8rOGgWbWRoeeTYAWG01UiKPZI6rADtMrh4g565+oVNWGVtZmXg y10g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:from:to:cc:subject:message-id :references:mime-version:content-disposition:in-reply-to; bh=GlZpEK9HpCLX1XVPm0LSC4rLTUHCcfxj2n178z32Y0M=; b=ud78lm3YxLYRB+jM+WLIzAE3U7dw51LtL2a+XxNJp2LNXC+5bMNcgd8cr5uFU7Z5hi FHSqSItenhaQWxTOqJL6A+Uibyt91GNKimujq80xc0gjjZ8s9Fdq+GC4cTsI0lY23bMt XBvGMqDq19QWIRHTGD+zN1/XYDo4tognqUhqxdYHkTUxNIDhztKNUCooxT4+3w6gnO2q lExmHHdMEL5mFaRxZBuPiqAjsM8rOCaspP729QkKor1b+c4sNLJiBQs+Me4RPtsiCICW 58Mnkn+/ZeGPc2qM50aA1UU1XAfs9JCY1u7Qh/J8ztgrduIu+q5lXnA1I8Wwq9M8k5B8 GKvg== X-Gm-Message-State: AOAM533DP5yxZfAppN5fvqj28LiklOztouB8Fns7TCnCSpKi5JnUeaPd Rcz3J+sZJ6zDXOkgqHIBGgyBrexUF2I= X-Google-Smtp-Source: ABdhPJz6slXGUUqNbPIe/QZEs+FilVAqqJJX0wFIgd8URduuQQBJKbAB2wMgf+BOJLU40MDsVaNPbw== X-Received: by 2002:a05:6a00:134b:b029:2bf:2c30:ebbd with SMTP id k11-20020a056a00134bb02902bf2c30ebbdmr30723883pfu.74.1621955768488; Tue, 25 May 2021 08:16:08 -0700 (PDT) Received: from google.com ([2620:15c:211:201:37cd:d6b4:7992:c290]) by smtp.gmail.com with ESMTPSA id s6sm2286711pjr.29.2021.05.25.08.16.05 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 25 May 2021 08:16:06 -0700 (PDT) Sender: Minchan Kim Date: Tue, 25 May 2021 08:16:03 -0700 From: Minchan Kim To: Chris Goldsworthy Cc: kernel test robot , Linus Torvalds , Laura Abbott , David Hildenbrand , John Dias , Matthew Wilcox , Michal Hocko , Suren Baghdasaryan , Vlastimil Babka , Andrew Morton , LKML , lkp@lists.01.org, lkp@intel.com, ying.huang@intel.com, feng.tang@intel.com, zhengjun.xing@intel.com, Minchan Kim Subject: Re: [mm] 8cc621d2f4: fio.write_iops -21.8% regression Message-ID: References: <20210520083144.GD14190@xsang-OptiPlex-9020> <45f761de51d514f77cc48214846c5f8f@codeaurora.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <45f761de51d514f77cc48214846c5f8f@codeaurora.org> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, May 24, 2021 at 10:37:49AM -0700, Chris Goldsworthy wrote: > Hi Minchan, > > This looks good to me, I just have some minor feedback. > > Thanks, Hi Chris, Thanks for the review. Please see below. > > Chris. > > On 2021-05-20 11:36, Minchan Kim wrote: > > On Thu, May 20, 2021 at 04:31:44PM +0800, kernel test robot wrote: > > > > > > > > > Greeting, > > > > > > FYI, we noticed a -21.8% regression of fio.write_iops due to commit: > > > > > > > > > commit: 8cc621d2f45ddd3dc664024a647ee7adf48d79a5 ("mm: fs: > > > invalidate BH LRU during page migration") > > > https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git master > > > > > > > > > in testcase: fio-basic > > > on test machine: 96 threads 2 sockets Intel(R) Xeon(R) Gold 6252 CPU > > > @ 2.10GHz with 256G memory > > > with following parameters: > > > > > > disk: 2pmem > > > fs: ext4 > > > runtime: 200s > > > nr_task: 50% > > > time_based: tb > > > rw: randwrite > > > bs: 4k > > > ioengine: libaio > > > test_size: 200G > > > cpufreq_governor: performance > > > ucode: 0x5003006 > > > > > > test-description: Fio is a tool that will spawn a number of threads > > > or processes doing a particular type of I/O action as specified by > > > the user. > > > test-url: https://github.com/axboe/fio > > > > > > > > > > > > If you fix the issue, kindly add following tag > > > Reported-by: kernel test robot > > > > > > > > > Details are as below: > > > --------------------------------------------------------------------------------------------------> > > > > > > > > > To reproduce: > > > > > > git clone https://github.com/intel/lkp-tests.git > > > cd lkp-tests > > > bin/lkp install job.yaml # job file is > > > attached in this email > > > bin/lkp split-job --compatible job.yaml # generate the yaml > > > file for lkp run > > > bin/lkp run generated-yaml-file > > > > Hi, > > > > I tried to insall the lkp-test in my machine by following above guide > > but failed > > due to package problems(I guess it's my problem since I use something > > particular > > environement). However, I guess it comes from increased miss ratio of > > bh_lrus > > since the patch caused more frequent invalidation of the bh_lrus calls > > compared > > to old. For example, lru_add_drain could be called from several hot > > places(e.g., > > unmap and pagevec_release from several path) and it could keeps > > invalidating > > bh_lrus. > > > > IMO, we should move the overhead from such hot path to cold one. How > > about this? > > > > From ebf4ede1cf32fb14d85f0015a3693cb8e1b8dbfe Mon Sep 17 00:00:00 2001 > > From: Minchan Kim > > Date: Thu, 20 May 2021 11:17:56 -0700 > > Subject: [PATCH] invalidate bh_lrus only at lru_add_drain_all > > > > Not-Yet-Signed-off-by: Minchan Kim > > --- > > mm/swap.c | 15 +++++++++++++-- > > 1 file changed, 13 insertions(+), 2 deletions(-) > > > > diff --git a/mm/swap.c b/mm/swap.c > > index dfb48cf9c2c9..d6168449e28c 100644 > > --- a/mm/swap.c > > +++ b/mm/swap.c > > @@ -642,7 +642,6 @@ void lru_add_drain_cpu(int cpu) > > pagevec_lru_move_fn(pvec, lru_lazyfree_fn); > > > > activate_page_drain(cpu); > > - invalidate_bh_lrus_cpu(cpu); > > } > > > > /** > > @@ -725,6 +724,17 @@ void lru_add_drain(void) > > local_unlock(&lru_pvecs.lock); > > } > > > > +void lru_and_bh_lrus_drain(void) > > +{ > > + int cpu; > > + > > + local_lock(&lru_pvecs.lock); > > + cpu = smp_processor_id(); > > + lru_add_drain_cpu(cpu); > > + local_unlock(&lru_pvecs.lock); > > + invalidate_bh_lrus_cpu(cpu); > > +} > > + > > Nit: drop int cpu? Do you mean to suggest using smp_processor_id at both places instead of local varaible? Since the invalidate_bh_lrus_cpu is called out of the lru_pvecs.lock, I wanted to express the draining happens at the same CPU via storing the CPU. > > > void lru_add_drain_cpu_zone(struct zone *zone) > > { > > local_lock(&lru_pvecs.lock); > > @@ -739,7 +749,7 @@ static DEFINE_PER_CPU(struct work_struct, > > lru_add_drain_work); > > > > static void lru_add_drain_per_cpu(struct work_struct *dummy) > > { > > - lru_add_drain(); > > + lru_and_bh_lrus_drain(); > > } > > > > /* > > @@ -881,6 +891,7 @@ void lru_cache_disable(void) > > __lru_add_drain_all(true); > > #else > > lru_add_drain(); > > + invalidate_bh_lrus_cpu(smp_processor_id()); > > #endif > > } > > Can't we replace the call to lru_add_drain() and > invalidate_bh_lrus_cpu(smp_processor_id()) with a single call to > lru_and_bh_lrus_drain()? Good idea. Thanks!