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Date: Fri, 16 Jan 2026 16:27:41 +0100
From: Christoph Hellwig <hch@lst.de>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Christoph Hellwig <hch@lst.de>, Marco Elver <elver@google.com>,
	Steven Rostedt <rostedt@goodmis.org>,
	Ingo Molnar <mingo@kernel.org>,
	Thomas Gleixner <tglx@linutronix.de>, Will Deacon <will@kernel.org>,
	Boqun Feng <boqun.feng@gmail.com>, Waiman Long <longman@redhat.com>,
	linux-kernel@vger.kernel.org, llvm@lists.linux.dev,
	Bart Van Assche <bvanassche@acm.org>
Subject: Re: [PATCH tip/locking/core] compiler-context-analysis: Support
 immediate acquisition after initialization
Message-ID: <20260116152741.GA19823@lst.de>
References: <20260115005231.1211866-1-elver@google.com> <20260115213311.GG830755@noisy.programming.kicks-ass.net> <aWmRlXZaOOUvU_Nv@elver.google.com> <20260116150750.GG831050@noisy.programming.kicks-ass.net> <20260116151043.GA18805@lst.de> <20260116152016.GI831050@noisy.programming.kicks-ass.net>
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On Fri, Jan 16, 2026 at 04:20:16PM +0100, Peter Zijlstra wrote:
> is *much* clearer than something like:
> 
> 	spinlock_init(&obj->lock);
> 	// init
> 	spinlock_deinit(&obj->lock);
> 
> Exactly because it has explicit scope. (also my deinit naming might not
> be optimal, it is ambiguous at best, probably confusing).

WTF is spinlock_deinit even supposed to be?

I though this is about:

	spin_lock_init(&obj->lock);
	spin_lock(&obj->lock);

> Not to mention that the scope things are far more robust vs error paths.

They are just a really hacked up clumsy way to provide what a very
limited version of what the capability analys provides, while messing
up the code.