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=-8.3 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=unavailable 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 2FE27C3A5A4 for ; Wed, 4 Sep 2019 05:02:45 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id DB6F422CF7 for ; Wed, 4 Sep 2019 05:02:44 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=joelfernandes.org header.i=@joelfernandes.org header.b="jhBWG15A" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org DB6F422CF7 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=joelfernandes.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 6F0BA6B0003; Wed, 4 Sep 2019 01:02:44 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 6A2FF6B0006; Wed, 4 Sep 2019 01:02:44 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 56A696B0007; Wed, 4 Sep 2019 01:02:44 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0078.hostedemail.com [216.40.44.78]) by kanga.kvack.org (Postfix) with ESMTP id 35A3A6B0003 for ; Wed, 4 Sep 2019 01:02:44 -0400 (EDT) Received: from smtpin22.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with SMTP id DC6C9AC1C for ; Wed, 4 Sep 2019 05:02:43 +0000 (UTC) X-FDA: 75896043006.22.paint59_34dac328d2e31 X-HE-Tag: paint59_34dac328d2e31 X-Filterd-Recvd-Size: 9530 Received: from mail-pl1-f193.google.com (mail-pl1-f193.google.com [209.85.214.193]) by imf49.hostedemail.com (Postfix) with ESMTP for ; Wed, 4 Sep 2019 05:02:43 +0000 (UTC) Received: by mail-pl1-f193.google.com with SMTP id k1so1655478pls.11 for ; Tue, 03 Sep 2019 22:02:42 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=joelfernandes.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=pDj1bZcKWdYkCPbWgz/Pz2qMGxk7UgTAcQYM9ROVqw0=; b=jhBWG15AlqK3xprU+HODJGbDECbvG7FlMM8fuoD8/LWLxPXWYohHnPZOtxNQ5RgeXK fEoCXJGVrlmBWkOM+IzI8pKDCqx1LTa7IvPd2jPNU3D9QdrV7tnq2n6pBlO2TsUHn0TN Dt3bmqAEc5aau0JUNifmRnKjgGhzlqklSKEVs= 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:user-agent; bh=pDj1bZcKWdYkCPbWgz/Pz2qMGxk7UgTAcQYM9ROVqw0=; b=RPZnjh+CW/vGsOyQv2lA/jes3BIO6n+I1NoF5kVvkzop/4EKbBxokiut8uAoinBFw9 gzguOlMJJ1QVZ4ddgQRI7+gUNjilzT7waInRCzRVdy9QN0UTDAjrSuo7u+lkjKyuLJV5 hOh4caAyfATg1T0ch0qB/qag93esk0g1a8k0Xcq3V8Rf44DAskxsOSen5wEOdXxfS5Lt azy1LpPB2tPywrDHpwzxEoTdh9qrHz9Ldjf1TRdqhoj087ShkxGqCKiVYkI6ZComsead OeF9u3U9hnFAUvuJcJVV3PIOVXuItwQZ4VXlE9UnJ0aTo3jpK69ZTknTNl0HECo9V4Bn PZtw== X-Gm-Message-State: APjAAAWSK7SXMpZ5345bXhim19h4QFAvgCCz+SHqMCinzFsyWR5av2Gh wOQd2JhVICBwYTOpxd0KKnoXqw== X-Google-Smtp-Source: APXvYqwFAoBQdwlA0QwMATvwlTnwADSgKV4Rci0PHl20Z+apUh4ALoinpglyCuZdFVxd1SkpK8eczQ== X-Received: by 2002:a17:902:830c:: with SMTP id bd12mr39733162plb.237.1567573361845; Tue, 03 Sep 2019 22:02:41 -0700 (PDT) Received: from localhost ([2620:15c:6:12:9c46:e0da:efbf:69cc]) by smtp.gmail.com with ESMTPSA id q132sm16031769pfq.16.2019.09.03.22.02.41 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 03 Sep 2019 22:02:41 -0700 (PDT) Date: Wed, 4 Sep 2019 01:02:40 -0400 From: Joel Fernandes To: Suren Baghdasaryan Cc: LKML , Tim Murray , Carmen Jackson , mayankgupta@google.com, Daniel Colascione , Steven Rostedt , Minchan Kim , Andrew Morton , kernel-team , "Aneesh Kumar K.V" , Dan Williams , Jerome Glisse , linux-mm , Matthew Wilcox , Michal Hocko , Ralph Campbell , Vlastimil Babka Subject: Re: [PATCH v2] mm: emit tracepoint when RSS changes by threshold Message-ID: <20190904050240.GD144846@google.com> References: <20190903200905.198642-1-joel@joelfernandes.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) 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, Sep 03, 2019 at 09:44:51PM -0700, Suren Baghdasaryan wrote: > On Tue, Sep 3, 2019 at 1:09 PM Joel Fernandes (Google) > wrote: > > > > Useful to track how RSS is changing per TGID to detect spikes in RSS and > > memory hogs. Several Android teams have been using this patch in various > > kernel trees for half a year now. Many reported to me it is really > > useful so I'm posting it upstream. > > > > Initial patch developed by Tim Murray. Changes I made from original patch: > > o Prevent any additional space consumed by mm_struct. > > o Keep overhead low by checking if tracing is enabled. > > o Add some noise reduction and lower overhead by emitting only on > > threshold changes. > > > > Co-developed-by: Tim Murray > > Signed-off-by: Tim Murray > > Signed-off-by: Joel Fernandes (Google) > > > > --- > > > > v1->v2: Added more commit message. > > > > Cc: carmenjackson@google.com > > Cc: mayankgupta@google.com > > Cc: dancol@google.com > > Cc: rostedt@goodmis.org > > Cc: minchan@kernel.org > > Cc: akpm@linux-foundation.org > > Cc: kernel-team@android.com > > > > include/linux/mm.h | 14 +++++++++++--- > > include/trace/events/kmem.h | 21 +++++++++++++++++++++ > > mm/memory.c | 20 ++++++++++++++++++++ > > 3 files changed, 52 insertions(+), 3 deletions(-) > > > > diff --git a/include/linux/mm.h b/include/linux/mm.h > > index 0334ca97c584..823aaf759bdb 100644 > > --- a/include/linux/mm.h > > +++ b/include/linux/mm.h > > @@ -1671,19 +1671,27 @@ static inline unsigned long get_mm_counter(struct mm_struct *mm, int member) > > return (unsigned long)val; > > } > > > > +void mm_trace_rss_stat(int member, long count, long value); > > + > > static inline void add_mm_counter(struct mm_struct *mm, int member, long value) > > { > > - atomic_long_add(value, &mm->rss_stat.count[member]); > > + long count = atomic_long_add_return(value, &mm->rss_stat.count[member]); > > + > > + mm_trace_rss_stat(member, count, value); > > } > > > > static inline void inc_mm_counter(struct mm_struct *mm, int member) > > { > > - atomic_long_inc(&mm->rss_stat.count[member]); > > + long count = atomic_long_inc_return(&mm->rss_stat.count[member]); > > + > > + mm_trace_rss_stat(member, count, 1); > > } > > > > static inline void dec_mm_counter(struct mm_struct *mm, int member) > > { > > - atomic_long_dec(&mm->rss_stat.count[member]); > > + long count = atomic_long_dec_return(&mm->rss_stat.count[member]); > > + > > + mm_trace_rss_stat(member, count, -1); > > } > > > > /* Optimized variant when page is already known not to be PageAnon */ > > diff --git a/include/trace/events/kmem.h b/include/trace/events/kmem.h > > index eb57e3037deb..8b88e04fafbf 100644 > > --- a/include/trace/events/kmem.h > > +++ b/include/trace/events/kmem.h > > @@ -315,6 +315,27 @@ TRACE_EVENT(mm_page_alloc_extfrag, > > __entry->change_ownership) > > ); > > > > +TRACE_EVENT(rss_stat, > > + > > + TP_PROTO(int member, > > + long count), > > + > > + TP_ARGS(member, count), > > + > > + TP_STRUCT__entry( > > + __field(int, member) > > + __field(long, size) > > + ), > > + > > + TP_fast_assign( > > + __entry->member = member; > > + __entry->size = (count << PAGE_SHIFT); > > + ), > > + > > + TP_printk("member=%d size=%ldB", > > + __entry->member, > > + __entry->size) > > + ); > > #endif /* _TRACE_KMEM_H */ > > > > /* This part must be outside protection */ > > diff --git a/mm/memory.c b/mm/memory.c > > index e2bb51b6242e..9d81322c24a3 100644 > > --- a/mm/memory.c > > +++ b/mm/memory.c > > @@ -72,6 +72,8 @@ > > #include > > #include > > > > +#include > > + > > #include > > #include > > #include > > @@ -140,6 +142,24 @@ static int __init init_zero_pfn(void) > > } > > core_initcall(init_zero_pfn); > > > > +/* > > + * This threshold is the boundary in the value space, that the counter has to > > + * advance before we trace it. Should be a power of 2. It is to reduce unwanted > > + * trace overhead. The counter is in units of number of pages. > > + */ > > +#define TRACE_MM_COUNTER_THRESHOLD 128 > > IIUC the counter has to change by 128 pages (512kB assuming 4kB pages) > before the change gets traced. Would it make sense to make this step > size configurable? For a system with limited memory size change of > 512kB might be considerable while on systems with plenty of memory > that might be negligible. Not even mentioning possible difference in > page sizes. Maybe something like > /sys/kernel/debug/tracing/rss_step_order with > TRACE_MM_COUNTER_THRESHOLD=(1< > +void mm_trace_rss_stat(int member, long count, long value) > > +{ > > + long thresh_mask = ~(TRACE_MM_COUNTER_THRESHOLD - 1); > > + > > + if (!trace_rss_stat_enabled()) > > + return; > > + > > + /* Threshold roll-over, trace it */ > > + if ((count & thresh_mask) != ((count - value) & thresh_mask)) > > + trace_rss_stat(member, count); > > +} > > > > #if defined(SPLIT_RSS_COUNTING) > > > > -- > > 2.23.0.187.g17f5b7556c-goog > > > > -- > > To unsubscribe from this group and stop receiving emails from it, send an email to kernel-team+unsubscribe@android.com. > >