With this change async.c does not rely anymore on any service from
main-loop.c, i.e. it is completely self-contained.
Reviewed-by: Anthony Liguori <aligu...@us.ibm.com>
Signed-off-by: Paolo Bonzini <pbonz...@redhat.com>
---
async.c | 30 ++++++++++++++++++++++++++----
qemu-aio.h | 18 ++++++++++++++++++
2 file modificati, 44 inserzioni(+), 4 rimozioni(-)
diff --git a/async.c b/async.c
index 4ffdd98..564526f 100644
--- a/async.c
+++ b/async.c
@@ -30,6 +30,7 @@
/* bottom halves (can be seen as timers which expire ASAP) */
struct QEMUBH {
+ AioContext *ctx;
QEMUBHFunc *cb;
void *opaque;
QEMUBH *next;
@@ -42,6 +43,7 @@ QEMUBH *aio_bh_new(AioContext *ctx, QEMUBHFunc *cb, void
*opaque)
{
QEMUBH *bh;
bh = g_malloc0(sizeof(QEMUBH));
+ bh->ctx = ctx;
bh->cb = cb;
bh->opaque = opaque;
bh->next = ctx->first_bh;
@@ -101,8 +103,7 @@ void qemu_bh_schedule(QEMUBH *bh)
return;
bh->scheduled = 1;
bh->idle = 0;
- /* stop the currently executing CPU to execute the BH ASAP */
- qemu_notify_event();
+ aio_notify(bh->ctx);
}
void qemu_bh_cancel(QEMUBH *bh)
@@ -177,11 +178,20 @@ aio_ctx_dispatch(GSource *source,
return true;
}
+static void
+aio_ctx_finalize(GSource *source)
+{
+ AioContext *ctx = (AioContext *) source;
+
+ aio_set_event_notifier(ctx, &ctx->notifier, NULL, NULL);
+ event_notifier_cleanup(&ctx->notifier);
+}
+
static GSourceFuncs aio_source_funcs = {
aio_ctx_prepare,
aio_ctx_check,
aio_ctx_dispatch,
- NULL
+ aio_ctx_finalize
};
GSource *aio_get_g_source(AioContext *ctx)
@@ -190,9 +200,21 @@ GSource *aio_get_g_source(AioContext *ctx)
return &ctx->source;
}
+void aio_notify(AioContext *ctx)
+{
+ event_notifier_set(&ctx->notifier);
+}
+
AioContext *aio_context_new(void)
{
- return (AioContext *) g_source_new(&aio_source_funcs, sizeof(AioContext));
+ AioContext *ctx;
+ ctx = (AioContext *) g_source_new(&aio_source_funcs, sizeof(AioContext));
+ event_notifier_init(&ctx->notifier, false);
+ aio_set_event_notifier(ctx, &ctx->notifier,
+ (EventNotifierHandler *)
+ event_notifier_test_and_clear, NULL);
+
+ return ctx;
}
void aio_context_ref(AioContext *ctx)
diff --git a/qemu-aio.h b/qemu-aio.h
index aedf66c..2354617 100644
--- a/qemu-aio.h
+++ b/qemu-aio.h
@@ -62,6 +62,9 @@ typedef struct AioContext {
* no callbacks are removed while we're walking and dispatching callbacks.
*/
int walking_bh;
+
+ /* Used for aio_notify. */
+ EventNotifier notifier;
} AioContext;
/* Returns 1 if there are still outstanding AIO requests; 0 otherwise */
@@ -102,6 +105,21 @@ void aio_context_unref(AioContext *ctx);
QEMUBH *aio_bh_new(AioContext *ctx, QEMUBHFunc *cb, void *opaque);
/**
+ * aio_notify: Force processing of pending events.
+ *
+ * Similar to signaling a condition variable, aio_notify forces
+ * aio_wait to exit, so that the next call will re-examine pending events.
+ * The caller of aio_notify will usually call aio_wait again very soon,
+ * or go through another iteration of the GLib main loop. Hence, aio_notify
+ * also has the side effect of recalculating the sets of file descriptors
+ * that the main loop waits for.
+ *
+ * Calling aio_notify is rarely necessary, because for example scheduling
+ * a bottom half calls it already.
+ */
+void aio_notify(AioContext *ctx);
+
+/**
* aio_bh_poll: Poll bottom halves for an AioContext.
*
* These are internal functions used by the QEMU main loop.
--
1.7.12.1
