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From: David Hildenbrand <david@redhat.com>
To: Steven Rostedt <rostedt@goodmis.org>
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()
Date: Fri, 1 Dec 2023 21:18:21 +0100	[thread overview]
Message-ID: <d426976d-4446-40a0-9088-82d9f4ebb950@redhat.com> (raw)
In-Reply-To: <20231201151535.06c7aaaf@gandalf.local.home>

On 01.12.23 21:15, Steven Rostedt wrote:
> 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).

Okay, I don't care that much about a "Fixes" annotation.

But I am *pretty* sure that this is not stable material, looking once 
again at the stable rules.

Anyhow, thanks for catching this!

-- 
Cheers,

David / dhildenb



  reply	other threads:[~2023-12-01 20:18 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-12-01 19:59 Steven Rostedt
2023-12-01 20:06 ` David Hildenbrand
2023-12-01 20:15   ` Steven Rostedt
2023-12-01 20:18     ` David Hildenbrand [this message]
2023-12-04 15:28 ` Vlastimil Babka

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