xprtrdma: Optimize rpcrdma_post_recvs()

Micro-optimization: In rpcrdma_post_recvs, since commit e340c2d6ef
("xprtrdma: Reduce the doorbell rate (Receive)"), the common case is
to return without doing anything. Found with perf.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
This commit is contained in:
Chuck Lever 2019-08-19 18:51:49 -04:00 committed by Anna Schumaker
parent 1738de336e
commit 435eba4ae0

View file

@ -1465,7 +1465,7 @@ rpcrdma_post_recvs(struct rpcrdma_xprt *r_xprt, bool temp)
count = 0;
needed = buf->rb_credits + (buf->rb_bc_srv_max_requests << 1);
if (ep->rep_receive_count > needed)
if (likely(ep->rep_receive_count > needed))
goto out;
needed -= ep->rep_receive_count;
if (!temp)