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From: Will Deacon <will@kernel.org>
To: Can Peng <pengcan@kylinos.cn>
Cc: catalin.marinas@arm.com, linux-arm-kernel@lists.infradead.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH 1/1] arm/syscalls: mark syscall invocation as likely in invoke_syscall
Date: Fri, 19 Sep 2025 12:40:57 +0100	[thread overview]
Message-ID: <aM1BSZV43DB_l5OU@willie-the-truck> (raw)
In-Reply-To: <20250919100042.497861-1-pengcan@kylinos.cn>

On Fri, Sep 19, 2025 at 06:00:42PM +0800, Can Peng wrote:
> The invoke_syscall() function is overwhelmingly called for
> valid system call entries. Annotate the main path with likely()
> to help the compiler generate better branch prediction hints,
> reducing CPU pipeline stalls due to mispredictions.
> 
> This is a micro-optimization targeting syscall-heavy workloads.

Does it actually make a measurable difference?

Will


  reply	other threads:[~2025-09-19 11:41 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2025-09-19 10:00 [PATCH 1/1] arm/syscalls: mark syscall invocation as likely in invoke_syscall Can Peng
2025-09-19 11:40 ` Will Deacon [this message]
2025-09-22 12:17   ` [PATCH 1/1] arm/syscalls: mark syscall invocation as Can Peng
2025-09-22 13:14 ` [PATCH 1/1] arm/syscalls: mark syscall invocation as likely in invoke_syscall Will Deacon

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