@@ -178,38 +178,17 @@ rpcrdma_sendcq_poll(struct ib_cq *cq, struct rpcrdma_ep *ep)
return 0;
}
-/*
- * Handle send, fast_reg_mr, and local_inv completions.
- *
- * Send events are typically suppressed and thus do not result
- * in an upcall. Occasionally one is signaled, however. This
- * prevents the provider's completion queue from wrapping and
- * losing a completion.
+/* Handle provider send completion upcalls.
*/
static void
rpcrdma_sendcq_upcall(struct ib_cq *cq, void *cq_context)
{
struct rpcrdma_ep *ep = (struct rpcrdma_ep *)cq_context;
- int rc;
-
- rc = rpcrdma_sendcq_poll(cq, ep);
- if (rc) {
- dprintk("RPC: %s: ib_poll_cq failed: %i\n",
- __func__, rc);
- return;
- }
- rc = ib_req_notify_cq(cq,
- IB_CQ_NEXT_COMP | IB_CQ_REPORT_MISSED_EVENTS);
- if (rc == 0)
- return;
- if (rc < 0) {
- dprintk("RPC: %s: ib_req_notify_cq failed: %i\n",
- __func__, rc);
- return;
- }
-
- rpcrdma_sendcq_poll(cq, ep);
+ do {
+ rpcrdma_sendcq_poll(cq, ep);
+ } while (ib_req_notify_cq(cq, IB_CQ_NEXT_COMP |
+ IB_CQ_REPORT_MISSED_EVENTS) > 0);
}
static void
@@ -273,42 +252,17 @@ out_schedule:
return rc;
}
-/*
- * Handle receive completions.
- *
- * It is reentrant but processes single events in order to maintain
- * ordering of receives to keep server credits.
- *
- * It is the responsibility of the scheduled tasklet to return
- * recv buffers to the pool. NOTE: this affects synchronization of
- * connection shutdown. That is, the structures required for
- * the completion of the reply handler must remain intact until
- * all memory has been reclaimed.
+/* Handle provider receive completion upcalls.
*/
static void
rpcrdma_recvcq_upcall(struct ib_cq *cq, void *cq_context)
{
struct rpcrdma_ep *ep = (struct rpcrdma_ep *)cq_context;
- int rc;
-
- rc = rpcrdma_recvcq_poll(cq, ep);
- if (rc) {
- dprintk("RPC: %s: ib_poll_cq failed: %i\n",
- __func__, rc);
- return;
- }
- rc = ib_req_notify_cq(cq,
- IB_CQ_NEXT_COMP | IB_CQ_REPORT_MISSED_EVENTS);
- if (rc == 0)
- return;
- if (rc < 0) {
- dprintk("RPC: %s: ib_req_notify_cq failed: %i\n",
- __func__, rc);
- return;
- }
-
- rpcrdma_recvcq_poll(cq, ep);
+ do {
+ rpcrdma_recvcq_poll(cq, ep);
+ } while (ib_req_notify_cq(cq, IB_CQ_NEXT_COMP |
+ IB_CQ_REPORT_MISSED_EVENTS) > 0);
}
static void
This is a note to let you know that I have just added a patch titled xprtrdma: Re-arm after missed events to the linux-4.2.y-queue branch of the 4.2.y-ckt extended stable tree which can be found at: http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-4.2.y-queue This patch is scheduled to be released in version 4.2.8-ckt1. If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 4.2.y-ckt tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Kamal ------ From b675b98661a284b73c81ce20214a073e267e2851 Mon Sep 17 00:00:00 2001 From: Chuck Lever <chuck.lever@oracle.com> Date: Sat, 24 Oct 2015 17:26:37 -0400 Subject: xprtrdma: Re-arm after missed events commit 7b3d770c67bc07db5035999e4f864c5f2ff7b10e upstream. ib_req_notify_cq(IB_CQ_REPORT_MISSED_EVENTS) returns a positive value if WCs were added to a CQ after the last completion upcall but before the CQ has been re-armed. Commit 7f23f6f6e388 ("xprtrmda: Reduce lock contention in completion handlers") assumed that when ib_req_notify_cq() returned a positive RC, the CQ had also been successfully re-armed, making it safe to return control to the provider without losing any completion signals. That is an invalid assumption. Change both completion handlers to continue polling while ib_req_notify_cq() returns a positive value. Fixes: 7f23f6f6e388 ("xprtrmda: Reduce lock contention in ...") Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: Sagi Grimberg <sagig@mellanox.com> Reviewed-by: Devesh Sharma <devesh.sharma@avagotech.com> Tested-By: Devesh Sharma <devesh.sharma@avagotech.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com> Signed-off-by: Kamal Mostafa <kamal@canonical.com> --- net/sunrpc/xprtrdma/verbs.c | 66 +++++++-------------------------------------- 1 file changed, 10 insertions(+), 56 deletions(-) -- 1.9.1