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[49.186.89.135]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-21da41415desm73556355ad.143.2025.01.27.22.44.55 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 27 Jan 2025 22:44:55 -0800 (PST) Received: from dave by dread.disaster.area with local (Exim 4.98) (envelope-from ) id 1tcfLB-0000000BTxH-2Z6P; Tue, 28 Jan 2025 17:44:53 +1100 Date: Tue, 28 Jan 2025 17:44:53 +1100 From: Dave Chinner To: Christoph Hellwig Cc: cem@kernel.org, djwong@kernel.org, dchinner@redhat.com, linux-xfs@vger.kernel.org, "Lai, Yi" , Carlos Maiolino Subject: Re: [PATCH v2] xfs: remove xfs_buf_cache.bc_lock Message-ID: References: <20250128052315.663868-1-hch@lst.de> Precedence: bulk X-Mailing-List: linux-xfs@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250128052315.663868-1-hch@lst.de> On Tue, Jan 28, 2025 at 06:22:58AM +0100, Christoph Hellwig wrote: > xfs_buf_cache.bc_lock serializes adding buffers to and removing them from > the hashtable. But as the rhashtable code already uses fine grained > internal locking for inserts and removals the extra protection isn't > actually required. > > It also happens to fix a lock order inversion vs b_lock added by the > recent lookup race fix. > > Fixes: ee10f6fcdb96 ("xfs: fix buffer lookup vs release race") > Reported-by: "Lai, Yi" > Signed-off-by: Christoph Hellwig > Reviewed-by: Carlos Maiolino > --- > > Changes since v1: > - document the initial buffer state vs lockless lookups Looks fine. Reviewed-by: Dave Chinner -- Dave Chinner david@fromorbit.com