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From:   Sebastian Andrzej Siewior <bigeasy@linutronix.de>
To:     Matthew Wilcox <willy@infradead.org>
Cc:     linux-fsdevel@vger.kernel.org, Thomas Gleixner <tglx@linutronix.de>
Subject: Re: xas_retry() based loops on PREEMPT_RT.
Message-ID: <20211115074122.3o4mjq4ddow7f2gp@linutronix.de>
References: <20211112173305.h36kodnm3awe3fn3@linutronix.de>
 <YY7kD/JWy9zuUGub@casper.infradead.org>
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On 2021-11-12 22:00:47 [+0000], Matthew Wilcox wrote:
> Readers should all be skipping over ZERO entries (as they do NULL
> entries), not restarting the iteration if they see one.  So it shouldn't
> factor into your "does it make progress" analysis, because an iteration
> should continue, not retry.
> 
> Also, I am not aware of any user of ZERO entries in the page cache.
> It's possible that somebody has added one without me noticing, but there
> wasn't one earlier.

Thank you for confirming.

Sebastian