2 * AioContext wait support
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25 #include "qemu/osdep.h"
26 #include "qemu/main-loop.h"
27 #include "block/aio-wait.h"
29 AioWait global_aio_wait;
31 static void dummy_bh_cb(void *opaque)
33 /* The point is to make AIO_WAIT_WHILE()'s aio_poll() return */
36 void aio_wait_kick(void)
39 * Paired with smp_mb in AIO_WAIT_WHILE. Here we have:
46 * And in AIO_WAIT_WHILE:
53 if (qatomic_read(&global_aio_wait.num_waiters)) {
54 aio_bh_schedule_oneshot(qemu_get_aio_context(), dummy_bh_cb, NULL);
64 /* Context: BH in IOThread */
65 static void aio_wait_bh(void *opaque)
67 AioWaitBHData *data = opaque;
69 data->cb(data->opaque);
75 void aio_wait_bh_oneshot(AioContext *ctx, QEMUBHFunc *cb, void *opaque)
77 AioWaitBHData data = {
82 assert(qemu_get_current_aio_context() == qemu_get_aio_context());
84 aio_bh_schedule_oneshot(ctx, aio_wait_bh, &data);
85 AIO_WAIT_WHILE(ctx, !data.done);