monitor: cleanup detection of qmp_dispatcher_co shutting down

Instead of overloading qmp_dispatcher_co_busy, make the coroutine
pointer NULL.  This will make things break spectacularly if somebody
tries to start a request after monitor_cleanup().

AIO_WAIT_WHILE_UNLOCKED() does not need qatomic_mb_read(), because
the macro contains all the necessary memory barriers.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Paolo Bonzini 2023-03-03 12:45:29 +01:00
parent 6ee7c82d0d
commit 3e6bed619a
2 changed files with 3 additions and 1 deletions

View file

@ -686,7 +686,7 @@ void monitor_cleanup(void)
AIO_WAIT_WHILE_UNLOCKED(NULL,
(aio_poll(iohandler_get_aio_context(), false),
qatomic_mb_read(&qmp_dispatcher_co_busy)));
qatomic_read(&qmp_dispatcher_co)));
/*
* We need to explicitly stop the I/O thread (but not destroy it),

View file

@ -226,6 +226,7 @@ void coroutine_fn monitor_qmp_dispatcher_co(void *data)
/* On shutdown, don't take any more requests from the queue */
if (qmp_dispatcher_co_shutdown) {
qatomic_set(&qmp_dispatcher_co, NULL);
return;
}
@ -250,6 +251,7 @@ void coroutine_fn monitor_qmp_dispatcher_co(void *data)
* yielded and were reentered from monitor_cleanup()
*/
if (qmp_dispatcher_co_shutdown) {
qatomic_set(&qmp_dispatcher_co, NULL);
return;
}
}