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Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SI4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 3798903 From: David Howells To: Marc Dionne cc: dhowells@redhat.com, linux-afs@lists.infradead.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] afs: Don't cache preferred address Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-ID: <159568.1709239291.1@warthog.procyon.org.uk> Date: Thu, 29 Feb 2024 20:41:31 +0000 Message-ID: <159569.1709239291@warthog.procyon.org.uk> X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.5 In the AFS fileserver rotation algorithm, don't cache the preferred address for the server as that will override the explicit preference if a non-preferred address responds first. Signed-off-by: David Howells cc: Marc Dionne cc: linux-afs@lists.infradead.org --- fs/afs/rotate.c | 21 ++++----------------- 1 file changed, 4 insertions(+), 17 deletions(-) diff --git a/fs/afs/rotate.c b/fs/afs/rotate.c index 700a27bc8c25..ed04bd1eeae8 100644 --- a/fs/afs/rotate.c +++ b/fs/afs/rotate.c @@ -602,6 +602,8 @@ bool afs_select_fileserver(struct afs_operation *op) goto wait_for_more_probe_results; alist = op->estate->addresses; + best_prio = -1; + addr_index = 0; for (i = 0; i < alist->nr_addrs; i++) { if (alist->addrs[i].prio > best_prio) { addr_index = i; @@ -609,9 +611,7 @@ bool afs_select_fileserver(struct afs_operation *op) } } - addr_index = READ_ONCE(alist->preferred); - if (!test_bit(addr_index, &set)) - addr_index = __ffs(set); + alist->preferred = addr_index; op->addr_index = addr_index; set_bit(addr_index, &op->addr_tried); @@ -656,12 +656,6 @@ bool afs_select_fileserver(struct afs_operation *op) next_server: trace_afs_rotate(op, afs_rotate_trace_next_server, 0); _debug("next"); - ASSERT(op->estate); - alist = op->estate->addresses; - if (op->call_responded && - op->addr_index != READ_ONCE(alist->preferred) && - test_bit(alist->preferred, &op->addr_tried)) - WRITE_ONCE(alist->preferred, op->addr_index); op->estate = NULL; goto pick_server; @@ -690,14 +684,7 @@ bool afs_select_fileserver(struct afs_operation *op) failed: trace_afs_rotate(op, afs_rotate_trace_failed, 0); op->flags |= AFS_OPERATION_STOP; - if (op->estate) { - alist = op->estate->addresses; - if (op->call_responded && - op->addr_index != READ_ONCE(alist->preferred) && - test_bit(alist->preferred, &op->addr_tried)) - WRITE_ONCE(alist->preferred, op->addr_index); - op->estate = NULL; - } + op->estate = NULL; _leave(" = f [failed %d]", afs_op_error(op)); return false; }