Merge remote-tracking branch 'remotes/stefanha/tags/block-pull-request' into staging
Pull request
These fixes make dataplane work again after the notify_me optimization was
added. They also solve QEMUBH memory leaks and fix a bug in dataplane's
cleanup code.
# gpg: Signature made Wed Jul 29 14:50:26 2015 BST using RSA key ID 81AB73C8
# gpg: Good signature from "Stefan Hajnoczi <stefanha@redhat.com>"
# gpg: aka "Stefan Hajnoczi <stefanha@gmail.com>"
* remotes/stefanha/tags/block-pull-request:
AioContext: force event loop iteration using BH
AioContext: avoid leaking BHs on cleanup
virtio-blk-dataplane: delete bottom half before the AioContext is freed
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
diff --git a/async.c b/async.c
index 9a98a74..efce14b 100644
--- a/async.c
+++ b/async.c
@@ -79,8 +79,10 @@
* aio_notify again if necessary.
*/
if (!bh->deleted && atomic_xchg(&bh->scheduled, 0)) {
- if (!bh->idle)
+ /* Idle BHs and the notify BH don't count as progress */
+ if (!bh->idle && bh != ctx->notify_dummy_bh) {
ret = 1;
+ }
bh->idle = 0;
bh->cb(bh->opaque);
}
@@ -230,7 +232,21 @@
{
AioContext *ctx = (AioContext *) source;
+ qemu_bh_delete(ctx->notify_dummy_bh);
thread_pool_free(ctx->thread_pool);
+
+ qemu_mutex_lock(&ctx->bh_lock);
+ while (ctx->first_bh) {
+ QEMUBH *next = ctx->first_bh->next;
+
+ /* qemu_bh_delete() must have been called on BHs in this AioContext */
+ assert(ctx->first_bh->deleted);
+
+ g_free(ctx->first_bh);
+ ctx->first_bh = next;
+ }
+ qemu_mutex_unlock(&ctx->bh_lock);
+
aio_set_event_notifier(ctx, &ctx->notifier, NULL);
event_notifier_cleanup(&ctx->notifier);
rfifolock_destroy(&ctx->lock);
@@ -285,8 +301,15 @@
static void aio_rfifolock_cb(void *opaque)
{
+ AioContext *ctx = opaque;
+
/* Kick owner thread in case they are blocked in aio_poll() */
- aio_notify(opaque);
+ qemu_bh_schedule(ctx->notify_dummy_bh);
+}
+
+static void notify_dummy_bh(void *opaque)
+{
+ /* Do nothing, we were invoked just to force the event loop to iterate */
}
static void event_notifier_dummy_cb(EventNotifier *e)
@@ -313,6 +336,8 @@
rfifolock_init(&ctx->lock, aio_rfifolock_cb, ctx);
timerlistgroup_init(&ctx->tlg, aio_timerlist_notify, ctx);
+ ctx->notify_dummy_bh = aio_bh_new(ctx, notify_dummy_bh, NULL);
+
return ctx;
}
diff --git a/hw/block/dataplane/virtio-blk.c b/hw/block/dataplane/virtio-blk.c
index 3db139b..6106e46 100644
--- a/hw/block/dataplane/virtio-blk.c
+++ b/hw/block/dataplane/virtio-blk.c
@@ -223,8 +223,8 @@
virtio_blk_data_plane_stop(s);
blk_op_unblock_all(s->conf->conf.blk, s->blocker);
error_free(s->blocker);
- object_unref(OBJECT(s->iothread));
qemu_bh_delete(s->bh);
+ object_unref(OBJECT(s->iothread));
g_free(s);
}
diff --git a/include/block/aio.h b/include/block/aio.h
index 9dd32e0..400b1b0 100644
--- a/include/block/aio.h
+++ b/include/block/aio.h
@@ -114,6 +114,9 @@
bool notified;
EventNotifier notifier;
+ /* Scheduling this BH forces the event loop it iterate */
+ QEMUBH *notify_dummy_bh;
+
/* Thread pool for performing work and receiving completion callbacks */
struct ThreadPool *thread_pool;