diff options
| -rw-r--r-- | async.c | 30 | ||||
| -rw-r--r-- | qemu-aio.h | 18 |
2 files changed, 44 insertions, 4 deletions
@@ -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 aedf66cfa1..2354617ed1 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. |