From 106f359cf4d613ebf54cb9f29721bb956fc3460e Mon Sep 17 00:00:00 2001
From: Trond Myklebust <trond.myklebust@primarydata.com>
Date: Sun, 3 Aug 2014 13:03:09 -0400
Subject: [PATCH] SUNRPC: Do not grab pool->sp_lock unnecessarily in
svc_get_next_xprt
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
---
net/sunrpc/svc_xprt.c | 15 ++++++++++-----
1 file changed, 10 insertions(+), 5 deletions(-)
diff --git a/net/sunrpc/svc_xprt.c b/net/sunrpc/svc_xprt.c
index 08e48cecfdcc7..08e49d1e17b30 100644
--- a/net/sunrpc/svc_xprt.c
+++ b/net/sunrpc/svc_xprt.c
@@ -651,8 +651,8 @@ static struct svc_xprt *svc_get_next_xprt(struct svc_rqst *rqstp, long timeout)
} else {
if (pool->sp_task_pending) {
pool->sp_task_pending = 0;
- spin_unlock_bh(&pool->sp_lock);
- return ERR_PTR(-EAGAIN);
+ xprt = ERR_PTR(-EAGAIN);
+ goto out;
}
/* No data pending. Go to sleep */
svc_thread_enqueue(pool, rqstp);
@@ -672,8 +672,8 @@ static struct svc_xprt *svc_get_next_xprt(struct svc_rqst *rqstp, long timeout)
*/
if (kthread_should_stop()) {
set_current_state(TASK_RUNNING);
- spin_unlock_bh(&pool->sp_lock);
- return ERR_PTR(-EINTR);
+ xprt = ERR_PTR(-EINTR);
+ goto out;
}
add_wait_queue(&rqstp->rq_wait, &wait);
@@ -683,8 +683,12 @@ static struct svc_xprt *svc_get_next_xprt(struct svc_rqst *rqstp, long timeout)
try_to_freeze();
- spin_lock_bh(&pool->sp_lock);
remove_wait_queue(&rqstp->rq_wait, &wait);
+ xprt = rqstp->rq_xprt;
+ if (xprt != NULL)
+ return xprt;
+
+ spin_lock_bh(&pool->sp_lock);
if (!time_left)
pool->sp_stats.threads_timedout++;
@@ -699,6 +703,7 @@ static struct svc_xprt *svc_get_next_xprt(struct svc_rqst *rqstp, long timeout)
return ERR_PTR(-EAGAIN);
}
}
+out:
spin_unlock_bh(&pool->sp_lock);
return xprt;
}
--
2.30.2