ib_req_notify_cq(IB_CQ_NEXT_COMP) is not guaranteed to generate a callback for the next completion entered since there is a race between arming the callback and another CQE being added to the queue. The IB_CQ_REPORT_MISSED_EVENTS flag was added to detect this race and allow the verbs consumer to call ib_poll_cq() and ib_req_notify_cq() again to avoid delays in processing the CQE.
Signed-off-by: Ralph Campbell <[email protected]> --- drivers/infiniband/ulp/srp/ib_srp.c | 7 ++++++- 1 files changed, 6 insertions(+), 1 deletions(-) diff --git a/drivers/infiniband/ulp/srp/ib_srp.c b/drivers/infiniband/ulp/srp/ib_srp.c index ed3f9eb..b0376f1 100644 --- a/drivers/infiniband/ulp/srp/ib_srp.c +++ b/drivers/infiniband/ulp/srp/ib_srp.c @@ -921,8 +921,9 @@ static void srp_recv_completion(struct ib_cq *cq, void *target_ptr) { struct srp_target_port *target = target_ptr; struct ib_wc wc; + int ret; - ib_req_notify_cq(cq, IB_CQ_NEXT_COMP); +again: while (ib_poll_cq(cq, 1, &wc) > 0) { if (wc.status) { shost_printk(KERN_ERR, target->scsi_host, @@ -934,6 +935,10 @@ static void srp_recv_completion(struct ib_cq *cq, void *target_ptr) srp_handle_recv(target, &wc); } + ret = ib_req_notify_cq(cq, IB_CQ_NEXT_COMP | + IB_CQ_REPORT_MISSED_EVENTS); + if (ret > 0) + goto again; } static void srp_send_completion(struct ib_cq *cq, void *target_ptr) -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
