From: Jeff Layton <jlayton@redhat.com>
Date: Mon, 23 Jul 2012 19:51:55 +0000 (-0400)
Subject: sunrpc: clarify comments on rpc_make_runnable
X-Git-Tag: v3.4.83~23
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=e8d5ce17375e2ece50659f287ad1a3daf2335d7e;p=thirdparty%2Fkernel%2Fstable.git

sunrpc: clarify comments on rpc_make_runnable

commit 506026c3ec270e18402f0c9d33fee37482c23861 upstream.

rpc_make_runnable is not generally called with the queue lock held, unless
it's waking up a task that has been sitting on a waitqueue. This is safe
when the task has not entered the FSM yet, but the comments don't really
spell this out.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Weng Meiling <wengmeiling.weng@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/net/sunrpc/sched.c b/net/sunrpc/sched.c
index 72d89e129caa8..38cca3259f3a2 100644
--- a/net/sunrpc/sched.c
+++ b/net/sunrpc/sched.c
@@ -302,8 +302,9 @@ EXPORT_SYMBOL_GPL(__rpc_wait_for_completion_task);
 /*
  * Make an RPC task runnable.
  *
- * Note: If the task is ASYNC, this must be called with
- * the spinlock held to protect the wait queue operation.
+ * Note: If the task is ASYNC, and is being made runnable after sitting on an
+ * rpc_wait_queue, this must be called with the queue spinlock held to protect
+ * the wait queue operation.
  */
 static void rpc_make_runnable(struct rpc_task *task)
 {