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From:   David Howells <dhowells@redhat.com>
In-Reply-To: <20221117115023.1350181-2-dwysocha@redhat.com>
References: <20221117115023.1350181-2-dwysocha@redhat.com> <20221117115023.1350181-1-dwysocha@redhat.com>
To:     Dave Wysochanski <dwysocha@redhat.com>
Cc:     dhowells@redhat.com, Daire Byrne <daire.byrne@gmail.com>,
        Benjamin Maynard <benmaynard@google.com>,
        linux-cachefs@redhat.com, linux-nfs@vger.kernel.org
Subject: Re: [PATCH 1/1] fscache: Fix oops due to race with cookie_lru and use_cookie
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Content-ID: <3716829.1668693167.1@warthog.procyon.org.uk>
Date:   Thu, 17 Nov 2022 13:52:47 +0000
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Dave Wysochanski <dwysocha@redhat.com> wrote:

> +		clear_bit(FSCACHE_COOKIE_DO_LRU_DISCARD, &cookie->flags);

Actually, can you do test_and_clear_bit() and then log a trace point, say:

	fscache_see_cookie(cookie, fscache_cookie_see_lru_discard_cancel);

if the bit was set.

David