linux-kernel - Re: [PATCH v3] xfs: Use try_cmpxchg() in xlog_cil_insert_pcp

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-Id: <172746273791.131348.18071682105497639956.b4-ty@kernel.org>
Date: Fri, 27 Sep 2024 20:45:37 +0200
From: Carlos Maiolino <cem@...nel.org>
To: linux-xfs@...r.kernel.org, linux-kernel@...r.kernel.org, 
 Uros Bizjak <ubizjak@...il.com>
Cc: Christoph Hellwig <hch@...radead.org>, 
 Chandan Babu R <chandan.babu@...cle.com>, 
 "Darrick J. Wong" <djwong@...nel.org>
Subject: Re: [PATCH v3] xfs: Use try_cmpxchg() in
 xlog_cil_insert_pcp_aggregate()

On Mon, 23 Sep 2024 14:22:17 +0200, Uros Bizjak wrote:
> Use !try_cmpxchg instead of cmpxchg (*ptr, old, new) != old in
> xlog_cil_insert_pcp_aggregate().  x86 CMPXCHG instruction returns
> success in ZF flag, so this change saves a compare after cmpxchg.
> 
> Also, try_cmpxchg implicitly assigns old *ptr value to "old" when
> cmpxchg fails. There is no need to re-read the value in the loop.
> 
> [...]

Applied to xfs-6.12-rc2, thanks!

[1/1] xfs: Use try_cmpxchg() in xlog_cil_insert_pcp_aggregate()
      commit: 6e19fd40d755a64f271687a21cd304ecba41a571

Best regards,
-- 
Carlos Maiolino <cem@...nel.org>