From 6c8c84f525100a1cade5698320b4abe43062e159 Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Wed, 7 Jul 2021 14:57:28 -0400 Subject: svcrdma: Fewer calls to wake_up() in Send completion handler Because wake_up() takes an IRQ-safe lock, it can be expensive, especially to call inside of a single-threaded completion handler. What's more, the Send wait queue almost never has waiters, so most of the time, this is an expensive no-op. As always, the goal is to reduce the average overhead of each completion, because a transport's completion handlers are single- threaded on one CPU core. This change reduces CPU utilization of the Send completion thread by 2-3% on my server. Signed-off-by: Chuck Lever Reviewed-By: Tom Talpey --- include/linux/sunrpc/svc_rdma.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/linux/sunrpc') diff --git a/include/linux/sunrpc/svc_rdma.h b/include/linux/sunrpc/svc_rdma.h index 3184465de3a0..57c60ffe76dd 100644 --- a/include/linux/sunrpc/svc_rdma.h +++ b/include/linux/sunrpc/svc_rdma.h @@ -207,6 +207,7 @@ extern void svc_rdma_send_error_msg(struct svcxprt_rdma *rdma, struct svc_rdma_send_ctxt *sctxt, struct svc_rdma_recv_ctxt *rctxt, int status); +extern void svc_rdma_wake_send_waiters(struct svcxprt_rdma *rdma, int avail); extern int svc_rdma_sendto(struct svc_rqst *); extern int svc_rdma_result_payload(struct svc_rqst *rqstp, unsigned int offset, unsigned int length); -- cgit v1.2.3-59-g8ed1b