diff options
author | Chuck Lever <chuck.lever@oracle.com> | 2020-07-08 16:09:53 -0400 |
---|---|---|
committer | Anna Schumaker <Anna.Schumaker@Netapp.com> | 2020-09-21 10:21:09 -0400 |
commit | 6f9f17287e78e5049931af2037b15b26d134a32a (patch) | |
tree | 61834c2cd426dc876c1cb267a2d09a0a431194d5 | |
parent | db0a86c4266ac36769f54e2ce33fff0300c9bc00 (diff) |
SUNRPC: Mitigate cond_resched() in xprt_transmit()
The original purpose of this expensive call is to prevent a long
queue of requests from blocking other work.
The cond_resched() call is unnecessary after just a single send
operation.
For longer queues, instead of invoking the kernel scheduler, simply
release the transport send lock and return to the RPC scheduler.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
-rw-r--r-- | net/sunrpc/xprt.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/net/sunrpc/xprt.c b/net/sunrpc/xprt.c index ceb190d1754d..f6c17e75f20e 100644 --- a/net/sunrpc/xprt.c +++ b/net/sunrpc/xprt.c @@ -1513,10 +1513,13 @@ xprt_transmit(struct rpc_task *task) { struct rpc_rqst *next, *req = task->tk_rqstp; struct rpc_xprt *xprt = req->rq_xprt; - int status; + int counter, status; spin_lock(&xprt->queue_lock); + counter = 0; while (!list_empty(&xprt->xmit_queue)) { + if (++counter == 20) + break; next = list_first_entry(&xprt->xmit_queue, struct rpc_rqst, rq_xmit); xprt_pin_rqst(next); @@ -1524,7 +1527,6 @@ xprt_transmit(struct rpc_task *task) status = xprt_request_transmit(next, task); if (status == -EBADMSG && next != req) status = 0; - cond_resched(); spin_lock(&xprt->queue_lock); xprt_unpin_rqst(next); if (status == 0) { |