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Date:   Sat, 28 Dec 2019 12:49:18 +0100
From:   Peter Zijlstra <peterz@infradead.org>
To:     Eric Biggers <ebiggers@kernel.org>
Cc:     linux-kernel@vger.kernel.org, Ingo Molnar <mingo@redhat.com>,
        Will Deacon <will@kernel.org>,
        Elena Reshetova <elena.reshetova@intel.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Kees Cook <keescook@chromium.org>,
        Anna-Maria Gleixner <anna-maria@linutronix.de>,
        Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Subject: Re: [PATCH] locking/refcount: add sparse annotations to dec-and-lock
 functions
Message-ID: <20191228114918.GU2827@hirez.programming.kicks-ass.net>
References: <20191226152922.2034-1-ebiggers@kernel.org>
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On Thu, Dec 26, 2019 at 09:29:22AM -0600, Eric Biggers wrote:
> From: Eric Biggers <ebiggers@google.com>
> 
> Wrap refcount_dec_and_lock() and refcount_dec_and_lock_irqsave() with
> macros using __cond_lock() so that 'sparse' doesn't report warnings
> about unbalanced locking when using them.
> 
> This is the same thing that's done for their atomic_t equivalents.
> 
> Don't annotate refcount_dec_and_mutex_lock(), because mutexes don't
> currently have sparse annotations.

I so f'ing hate that __cond_lock() crap. Previously I've suggested
fixing sparse instead of making such an atrocious trainwreck of the
code.