Cleanups for the socket locking mechanism.
Improve RPC request ordering by ensuring that RPC tasks that are
already queued on xprt->sending get sent before tasks that happen to
get scheduled just when there is a free slot.
In case the socket send buffer is full, queue the tasks on
xprt->pending rather than xprt->sending in order to eliminate the risk
of accidental wakeups from xprt_release_write() and xprt_write_space().
Cheers,
Trond
diff -u --recursive --new-file linux-2.5.25-rtt3/net/sunrpc/xprt.c linux-2.5.25-xprt_write/net/sunrpc/xprt.c
--- linux-2.5.25-rtt3/net/sunrpc/xprt.c Tue Jul 16 15:28:49 2002
+++ linux-2.5.25-xprt_write/net/sunrpc/xprt.c Tue Jul 16 15:30:05 2002
@@ -154,17 +154,35 @@
return retval;
}
+static void
+__xprt_lock_write_next(struct rpc_xprt *xprt)
+{
+ struct rpc_task *task;
+
+ if (xprt->snd_task)
+ return;
+ task = rpc_wake_up_next(&xprt->sending);
+ if (!task)
+ return;
+ xprt->snd_task = task;
+}
+
/*
* Releases the socket for use by other requests.
*/
static void
+__xprt_release_write(struct rpc_xprt *xprt, struct rpc_task *task)
+{
+ if (xprt->snd_task == task)
+ xprt->snd_task = NULL;
+ __xprt_lock_write_next(xprt);
+}
+
+static inline void
xprt_release_write(struct rpc_xprt *xprt, struct rpc_task *task)
{
spin_lock_bh(&xprt->sock_lock);
- if (xprt->snd_task == task) {
- xprt->snd_task = NULL;
- rpc_wake_up_next(&xprt->sending);
- }
+ __xprt_release_write(xprt, task);
spin_unlock_bh(&xprt->sock_lock);
}
@@ -429,7 +447,7 @@
/* if the socket is already closing, delay 5 secs */
if ((1<<inet->state) & ~(TCP_SYN_SENT|TCP_SYN_RECV))
task->tk_timeout = 5*HZ;
- rpc_sleep_on(&xprt->sending, task, xprt_reconn_status, NULL);
+ rpc_sleep_on(&xprt->pending, task, xprt_reconn_status, NULL);
release_sock(inet);
return;
}
@@ -883,7 +901,7 @@
xprt->tcp_flags = XPRT_COPY_RECM | XPRT_COPY_XID;
spin_lock(&xprt->sock_lock);
- if (xprt->snd_task && xprt->snd_task->tk_rpcwait == &xprt->sending)
+ if (xprt->snd_task && xprt->snd_task->tk_rpcwait == &xprt->pending)
rpc_wake_up_task(xprt->snd_task);
spin_unlock(&xprt->sock_lock);
break;
@@ -920,7 +938,7 @@
if (!xprt_test_and_set_wspace(xprt)) {
spin_lock(&xprt->sock_lock);
- if (xprt->snd_task && xprt->snd_task->tk_rpcwait == &xprt->sending)
+ if (xprt->snd_task && xprt->snd_task->tk_rpcwait == &xprt->pending)
rpc_wake_up_task(xprt->snd_task);
spin_unlock(&xprt->sock_lock);
}
@@ -1078,7 +1096,7 @@
spin_lock_bh(&xprt->sock_lock);
if (!xprt_wspace(xprt)) {
task->tk_timeout = req->rq_timeout.to_current;
- rpc_sleep_on(&xprt->sending, task, NULL, NULL);
+ rpc_sleep_on(&xprt->pending, task, NULL, NULL);
}
spin_unlock_bh(&xprt->sock_lock);
return;
@@ -1094,9 +1112,10 @@
if (xprt->stream)
xprt_disconnect(xprt);
req->rq_bytes_sent = 0;
- goto out_release;
}
-
+ out_release:
+ xprt_release_write(xprt, task);
+ return;
out_receive:
dprintk("RPC: %4d xmit complete\n", task->tk_pid);
/* Set the task's receive timeout value */
@@ -1111,9 +1130,8 @@
spin_lock_bh(&xprt->sock_lock);
if (!req->rq_received)
rpc_sleep_on(&xprt->pending, task, NULL, xprt_timer);
+ __xprt_release_write(xprt, task);
spin_unlock_bh(&xprt->sock_lock);
- out_release:
- xprt_release_write(xprt, task);
}
/*
@@ -1218,14 +1236,10 @@
struct rpc_xprt *xprt = task->tk_xprt;
struct rpc_rqst *req;
- if (xprt->snd_task == task) {
- if (xprt->stream)
- xprt_disconnect(xprt);
- xprt_release_write(xprt, task);
- }
if (!(req = task->tk_rqstp))
return;
spin_lock_bh(&xprt->sock_lock);
+ __xprt_release_write(xprt, task);
if (!list_empty(&req->rq_list))
list_del(&req->rq_list);
spin_unlock_bh(&xprt->sock_lock);
-
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This archive was generated by hypermail 2b29 : Tue Jul 23 2002 - 22:00:20 EST