Revert "iothread: release iothread around aio_poll"

This reverts commit a0710f7995f914e3044e5899bd8ff6c43c62f916.

In qemu-devel email message <556DBF87.2020908@de.ibm.com>, Christian
Borntraeger writes:

  Having many guests all with a kernel/ramdisk (via -kernel) and
  several null block devices will result in hangs. All hanging
  guests are in partition detection code waiting for an I/O to return
  so very early maybe even the first I/O.

  Reverting that commit "fixes" the hangs.

Reverting this commit for the 2.4 release.  More time is needed to
investigate and correct this patch.

Reported-by: Christian Borntraeger <borntraeger@de.ibm.com>
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

1 files changed, 8 insertions, 11 deletions

diff --git a/tests/test-aio.c b/tests/test-aio.c
index 4b0cb45d31..a7cb5c9915 100644
--- a/tests/test-aio.c
+++ b/tests/test-aio.c
@@ -107,7 +107,6 @@ static void test_notify(void)
 
 typedef struct {
     QemuMutex start_lock;
-    EventNotifier notifier;
     bool thread_acquired;
 } AcquireTestData;
 
@@ -119,8 +118,6 @@ static void *test_acquire_thread(void *opaque)
     qemu_mutex_lock(&data->start_lock);
     qemu_mutex_unlock(&data->start_lock);
 
-    g_usleep(500000);
-    event_notifier_set(&data->notifier);
     aio_context_acquire(ctx);
     aio_context_release(ctx);
 
@@ -129,19 +126,20 @@ static void *test_acquire_thread(void *opaque)
     return NULL;
 }
 
-static void dummy_notifier_read(EventNotifier *n)
+static void dummy_notifier_read(EventNotifier *unused)
 {
-    event_notifier_test_and_clear(n);
+    g_assert(false); /* should never be invoked */
 }
 
 static void test_acquire(void)
 {
     QemuThread thread;
+    EventNotifier notifier;
     AcquireTestData data;
 
     /* Dummy event notifier ensures aio_poll() will block */
-    event_notifier_init(&data.notifier, false);
-    aio_set_event_notifier(ctx, &data.notifier, dummy_notifier_read);
+    event_notifier_init(&notifier, false);
+    aio_set_event_notifier(ctx, &notifier, dummy_notifier_read);
     g_assert(!aio_poll(ctx, false)); /* consume aio_notify() */
 
     qemu_mutex_init(&data.start_lock);
@@ -155,13 +153,12 @@ static void test_acquire(void)
     /* Block in aio_poll(), let other thread kick us and acquire context */
     aio_context_acquire(ctx);
     qemu_mutex_unlock(&data.start_lock); /* let the thread run */
-    g_assert(aio_poll(ctx, true));
-    g_assert(!data.thread_acquired);
+    g_assert(!aio_poll(ctx, true));
     aio_context_release(ctx);
 
     qemu_thread_join(&thread);
-    aio_set_event_notifier(ctx, &data.notifier, NULL);
-    event_notifier_cleanup(&data.notifier);
+    aio_set_event_notifier(ctx, &notifier, NULL);
+    event_notifier_cleanup(&notifier);
 
     g_assert(data.thread_acquired);
 }