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Date:   Fri, 1 Dec 2023 15:15:35 -0500
From:   Steven Rostedt <rostedt@goodmis.org>
To:     David Hildenbrand <david@redhat.com>
Cc:     LKML <linux-kernel@vger.kernel.org>, linux-mm@kvack.org,
        Vlastimil Babka <vbabka@suse.cz>,
        Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [PATCH] mm/rmap: Fix misplaced parenthesis of a likely()
Message-ID: <20231201151535.06c7aaaf@gandalf.local.home>
In-Reply-To: <2d691c11-fa97-4f56-a4c4-c7f466c81d3a@redhat.com>
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        <2d691c11-fa97-4f56-a4c4-c7f466c81d3a@redhat.com>
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On Fri, 1 Dec 2023 21:06:22 +0100
David Hildenbrand <david@redhat.com> wrote:

> But
> 
> > Cc: stable@vger.kernel.org  
> 
> stable, really? Why?
> 
> > Fixes:fb3d824d1a46c ("mm/rmap: split page_dup_rmap() into page_dup_file_rmap() and page_try_dup_anon_rmap()")  
> 
> and does it even fix a real bug?

As a performance person, who measures likely and unlikely results (the
ftrace ring buffer was sped up by over 50% with strategically placed
likely/unlikely annotation). I find this to be a real bug, and something I
would want backported to the kernels we maintain in ChromeOS (which uses
upstream stable kernels).

-- Steve