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Registered in England and Wales under Company Registration No. 3798903 From: David Howells In-Reply-To: <20221226103309.953112-2-houtao@huaweicloud.com> References: <20221226103309.953112-2-houtao@huaweicloud.com> <20221226103309.953112-1-houtao@huaweicloud.com> To: Hou Tao Subject: Re: [PATCH v2 1/2] fscache: Use wait_on_bit() to wait for the freeing of relinquished volume MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-ID: <2431837.1673453170.1@warthog.procyon.org.uk> Date: Wed, 11 Jan 2023 16:06:10 +0000 Message-ID: <2431838.1673453170@warthog.procyon.org.uk> X-Scanned-By: MIMEDefang 3.1 on 10.11.54.8 X-BeenThere: linux-erofs@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Development of Linux EROFS file system List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Jeff Layton , linux-kernel@vger.kernel.org, dhowells@redhat.com, linux-cachefs@redhat.com, houtao1@huawei.com, linux-erofs@lists.ozlabs.org Errors-To: linux-erofs-bounces+linux-erofs=archiver.kernel.org@lists.ozlabs.org Sender: "Linux-erofs" Hou Tao wrote: > clear_bit(FSCACHE_VOLUME_ACQUIRE_PENDING, &cursor->flags); > + /* > + * Paired with barrier in wait_on_bit(). Check > + * wake_up_bit() and waitqueue_active() for details. > + */ > + smp_mb__after_atomic(); > wake_up_bit(&cursor->flags, FSCACHE_VOLUME_ACQUIRE_PENDING); What two values are you applying a partial ordering to? David