2 * AioContext wait support
4 * Copyright (C) 2018 Red Hat, Inc.
6 * Permission is hereby granted, free of charge, to any person obtaining a copy
7 * of this software and associated documentation files (the "Software"), to deal
8 * in the Software without restriction, including without limitation the rights
9 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10 * copies of the Software, and to permit persons to whom the Software is
11 * furnished to do so, subject to the following conditions:
13 * The above copyright notice and this permission notice shall be included in
14 * all copies or substantial portions of the Software.
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
25 #include "qemu/osdep.h"
26 #include "qemu/main-loop.h"
27 #include "block/aio-wait.h"
29 static void dummy_bh_cb(void *opaque
)
31 /* The point is to make AIO_WAIT_WHILE()'s aio_poll() return */
34 void aio_wait_kick(AioWait
*wait
)
36 /* The barrier (or an atomic op) is in the caller. */
37 if (atomic_read(&wait
->need_kick
)) {
38 aio_bh_schedule_oneshot(qemu_get_aio_context(), dummy_bh_cb
, NULL
);
49 /* Context: BH in IOThread */
50 static void aio_wait_bh(void *opaque
)
52 AioWaitBHData
*data
= opaque
;
54 data
->cb(data
->opaque
);
57 aio_wait_kick(&data
->wait
);
60 void aio_wait_bh_oneshot(AioContext
*ctx
, QEMUBHFunc
*cb
, void *opaque
)
62 AioWaitBHData data
= {
67 assert(qemu_get_current_aio_context() == qemu_get_aio_context());
69 aio_bh_schedule_oneshot(ctx
, aio_wait_bh
, &data
);
70 AIO_WAIT_WHILE(&data
.wait
, ctx
, !data
.done
);