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Date: Wed, 25 Jun 2025 13:59:29 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Boqun Feng <boqun.feng@gmail.com>
Cc: linux-kernel@vger.kernel.org, rcu@vger.kernel.org, lkmm@lists.linux.dev,
	Ingo Molnar <mingo@kernel.org>, Will Deacon <will@kernel.org>,
	Waiman Long <longman@redhat.com>,
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	Erik Lundgren <elundgren@meta.com>
Subject: Re: [PATCH 8/8] locking/lockdep: Use shazptr to protect the key
 hashlist
Message-ID: <20250625115929.GF1613376@noisy.programming.kicks-ass.net>
References: <20250625031101.12555-1-boqun.feng@gmail.com>
 <20250625031101.12555-9-boqun.feng@gmail.com>
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In-Reply-To: <20250625031101.12555-9-boqun.feng@gmail.com>

On Tue, Jun 24, 2025 at 08:11:01PM -0700, Boqun Feng wrote:

> +	/* Need preemption disable for using shazptr. */
> +	guard(preempt)();
> +
> +	/* Protect the list search with shazptr. */
> +	guard(shazptr)(hash_head);

OK, this is the end of the series, and so far every single user is doing
both a preempt and a shazptr guard. Why can't we simplify this and have
the shazptr guard imply preempt-disable?