SUNRPC: Ensure we always bump the backlog queue in xprt_free_slot
Trond Myklebust [Thu, 1 Dec 2011 19:16:17 +0000 (14:16 -0500)]
commit c25573b5134294c0be82bfaecc6d08136835b271 upstream.

Whenever we free a slot, we know that the resulting xprt->num_reqs will
be less than xprt->max_reqs, so we know that we can release at least one
backlogged rpc_task.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

net/sunrpc/xprt.c

index f4385e4..c64c0ef 100644 (file)
@@ -995,13 +995,11 @@ out_init_req:
 
 static void xprt_free_slot(struct rpc_xprt *xprt, struct rpc_rqst *req)
 {
-       if (xprt_dynamic_free_slot(xprt, req))
-               return;
-
-       memset(req, 0, sizeof(*req));   /* mark unused */
-
        spin_lock(&xprt->reserve_lock);
-       list_add(&req->rq_list, &xprt->free);
+       if (!xprt_dynamic_free_slot(xprt, req)) {
+               memset(req, 0, sizeof(*req));   /* mark unused */
+               list_add(&req->rq_list, &xprt->free);
+       }
        rpc_wake_up_next(&xprt->backlog);
        spin_unlock(&xprt->reserve_lock);
 }