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Message-ID: <6595b15eba54cf5efc2ea801ea91c41681f33c61.camel@redhat.com>
Subject: Re: [PATCH 4/6] locking/lockdep: Clean up check_redundant() a bit
From:   Qian Cai <qcai@redhat.com>
To:     Peter Zijlstra <peterz@infradead.org>, mingo@kernel.org,
        will@kernel.org, boqun.feng@gmail.com
Cc:     linux-kernel@vger.kernel.org, tglx@linutronix.de,
        bigeasy@linutronix.de
Date:   Thu, 10 Dec 2020 15:09:51 -0500
In-Reply-To: <20201210144619.870033538@infradead.org>
References: <20201210144254.583402167@infradead.org>
         <20201210144619.870033538@infradead.org>
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On Thu, 2020-12-10 at 15:42 +0100, Peter Zijlstra wrote:
[]
>  /*
> @@ -2706,6 +2666,55 @@ static inline int check_irq_usage(struct
>  }
>  #endif /* CONFIG_TRACE_IRQFLAGS */
>  
> +#ifdef CONFIG_LOCKDEP_SMALL
> +/*
> + * Check that the dependency graph starting at <src> can lead to
> + * <target> or not. If it can, <src> -> <target> dependency is already
> + * in the graph.
> + *
> + * Return BFS_RMATCH if it does, or BFS_RMATCH if it does not, return BFS_E* if
> + * any error appears in the bfs search.

Correction -- or BFS_RNOMATCH if it does not.