Return-Path: linux-nfs-owner@vger.kernel.org Received: from mail-ig0-f181.google.com ([209.85.213.181]:36896 "EHLO mail-ig0-f181.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755830AbaGVOxj (ORCPT ); Tue, 22 Jul 2014 10:53:39 -0400 Subject: [PATCH v4 18/21] xprtrdma: Schedule reply tasklet once per upcall From: Chuck Lever To: Anna.Schumaker@netapp.com Cc: linux-rdma@vger.kernel.org, linux-nfs@vger.kernel.org Date: Tue, 22 Jul 2014 10:53:35 -0400 Message-ID: <20140722145335.6010.510.stgit@manet.1015granger.net> In-Reply-To: <20140722144459.6010.99389.stgit@manet.1015granger.net> References: <20140722144459.6010.99389.stgit@manet.1015granger.net> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Sender: linux-nfs-owner@vger.kernel.org List-ID: Minor optimization: grab rpcrdma_tk_lock_g and disable hard IRQs just once after clearing the receive completion queue. Signed-off-by: Chuck Lever Tested-by: Steve Wise Tested-by: Shirley Ma Tested-by: Devesh Sharma --- net/sunrpc/xprtrdma/verbs.c | 31 +++++++++++++++---------------- 1 file changed, 15 insertions(+), 16 deletions(-) diff --git a/net/sunrpc/xprtrdma/verbs.c b/net/sunrpc/xprtrdma/verbs.c index f7691be..3563467 100644 --- a/net/sunrpc/xprtrdma/verbs.c +++ b/net/sunrpc/xprtrdma/verbs.c @@ -105,17 +105,6 @@ rpcrdma_run_tasklet(unsigned long data) static DECLARE_TASKLET(rpcrdma_tasklet_g, rpcrdma_run_tasklet, 0UL); -static inline void -rpcrdma_schedule_tasklet(struct rpcrdma_rep *rep) -{ - unsigned long flags; - - spin_lock_irqsave(&rpcrdma_tk_lock_g, flags); - list_add_tail(&rep->rr_list, &rpcrdma_tasklets_g); - spin_unlock_irqrestore(&rpcrdma_tk_lock_g, flags); - tasklet_schedule(&rpcrdma_tasklet_g); -} - static void rpcrdma_qp_async_error_upcall(struct ib_event *event, void *context) { @@ -214,7 +203,7 @@ rpcrdma_sendcq_upcall(struct ib_cq *cq, void *cq_context) } static void -rpcrdma_recvcq_process_wc(struct ib_wc *wc) +rpcrdma_recvcq_process_wc(struct ib_wc *wc, struct list_head *sched_list) { struct rpcrdma_rep *rep = (struct rpcrdma_rep *)(unsigned long)wc->wr_id; @@ -245,28 +234,38 @@ rpcrdma_recvcq_process_wc(struct ib_wc *wc) } out_schedule: - rpcrdma_schedule_tasklet(rep); + list_add_tail(&rep->rr_list, sched_list); } static int rpcrdma_recvcq_poll(struct ib_cq *cq, struct rpcrdma_ep *ep) { + struct list_head sched_list; struct ib_wc *wcs; int budget, count, rc; + unsigned long flags; + INIT_LIST_HEAD(&sched_list); budget = RPCRDMA_WC_BUDGET / RPCRDMA_POLLSIZE; do { wcs = ep->rep_recv_wcs; rc = ib_poll_cq(cq, RPCRDMA_POLLSIZE, wcs); if (rc <= 0) - return rc; + goto out_schedule; count = rc; while (count-- > 0) - rpcrdma_recvcq_process_wc(wcs++); + rpcrdma_recvcq_process_wc(wcs++, &sched_list); } while (rc == RPCRDMA_POLLSIZE && --budget); - return 0; + rc = 0; + +out_schedule: + spin_lock_irqsave(&rpcrdma_tk_lock_g, flags); + list_splice_tail(&sched_list, &rpcrdma_tasklets_g); + spin_unlock_irqrestore(&rpcrdma_tk_lock_g, flags); + tasklet_schedule(&rpcrdma_tasklet_g); + return rc; } /*