[PATCH] remove sleep_on from sunrpc

From: Manfred Spraul
Date: Sat Jan 17 2004 - 13:49:06 EST


sunrpc uses sleep_on to wait until the rpciod thread has died. This
could race if rpciod_down is called without lock_kernel. Right now all
calls in the main tree are under lock_kernel, but rpciod is an exported
function and sleep_on should die.
Additionally, I've replaced spin_lock_irqsave() with spin_lock_irq():
rpciod_down sleeps, interrupts are guaranteed to be enabled.

--
Manfred




--- 2.6/net/sunrpc/sched.c 2004-01-17 12:19:50.000000000 +0100
+++ build-2.6/net/sunrpc/sched.c 2004-01-17 12:52:33.000000000 +0100
@@ -1060,7 +1060,7 @@
void
rpciod_down(void)
{
- unsigned long flags;
+ DECLARE_WAITQUEUE(wait, current);

down(&rpciod_sema);
dprintk("rpciod_down pid %d sema %d\n", rpciod_pid, rpciod_users);
@@ -1085,17 +1085,22 @@
/*
* Display a message if we're going to wait longer.
*/
- while (rpciod_pid) {
+ add_wait_queue(&rpciod_killer, &wait);
+ for (;;) {
+ set_current_state(TASK_INTERRUPTIBLE);
+ if (rpciod_pid == 0)
+ break;
dprintk("rpciod_down: waiting for pid %d to exit\n", rpciod_pid);
if (signalled()) {
dprintk("rpciod_down: caught signal\n");
break;
}
- interruptible_sleep_on(&rpciod_killer);
+ schedule();
}
- spin_lock_irqsave(&current->sighand->siglock, flags);
+ remove_wait_queue(&rpciod_killer, &wait);
+ spin_lock_irq(&current->sighand->siglock);
recalc_sigpending();
- spin_unlock_irqrestore(&current->sighand->siglock, flags);
+ spin_unlock_irq(&current->sighand->siglock);
out:
up(&rpciod_sema);
}