| From e020c6800c9621a77223bf2c1ff68180e41e8ebf Mon Sep 17 00:00:00 2001 |
| From: Trond Myklebust <Trond.Myklebust@netapp.com> |
| Date: Tue, 15 Mar 2011 19:56:30 -0400 |
| Subject: SUNRPC: Ensure we always run the tk_callback before tk_action |
| |
| From: Trond Myklebust <Trond.Myklebust@netapp.com> |
| |
| commit e020c6800c9621a77223bf2c1ff68180e41e8ebf upstream. |
| |
| This fixes a race in which the task->tk_callback() puts the rpc_task |
| to sleep, setting a new callback. Under certain circumstances, the current |
| code may end up executing the task->tk_action before it gets round to the |
| callback. |
| |
| Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> |
| |
| --- |
| net/sunrpc/sched.c | 14 ++++++-------- |
| 1 file changed, 6 insertions(+), 8 deletions(-) |
| |
| --- a/net/sunrpc/sched.c |
| +++ b/net/sunrpc/sched.c |
| @@ -627,14 +627,12 @@ static void __rpc_execute(struct rpc_tas |
| save_callback = task->tk_callback; |
| task->tk_callback = NULL; |
| save_callback(task); |
| - } |
| - |
| - /* |
| - * Perform the next FSM step. |
| - * tk_action may be NULL when the task has been killed |
| - * by someone else. |
| - */ |
| - if (!RPC_IS_QUEUED(task)) { |
| + } else { |
| + /* |
| + * Perform the next FSM step. |
| + * tk_action may be NULL when the task has been killed |
| + * by someone else. |
| + */ |
| if (task->tk_action == NULL) |
| break; |
| task->tk_action(task); |