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Date:   Tue, 10 May 2022 18:55:06 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Uros Bizjak <ubizjak@gmail.com>
Cc:     x86@kernel.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        "H. Peter Anvin" <hpa@zytor.com>, Will Deacon <will@kernel.org>,
        Boqun Feng <boqun.feng@gmail.com>,
        Mark Rutland <mark.rutland@arm.com>,
        "Paul E. McKenney" <paulmck@kernel.org>,
        Marco Elver <elver@google.com>
Subject: Re: [PATCH] locking/atomic/x86: Introduce try_cmpxchg64
Message-ID: <20220510165506.GP76023@worktop.programming.kicks-ass.net>
References: <20220510154217.5216-1-ubizjak@gmail.com>
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On Tue, May 10, 2022 at 05:42:17PM +0200, Uros Bizjak wrote:
> This patch adds try_cmpxchg64 to improve code around cmpxchg8b.  While
> the resulting code improvements on x86_64 are minor (a compare and a move saved),
> the improvements on x86_32 are quite noticeable. The code improves from:

What user of cmpxchg64 is this?