2379247810
Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Message-Id: <20221221131435.3851212-2-armbru@redhat.com>
80 lines
2.1 KiB
C
80 lines
2.1 KiB
C
/*
|
|
* QEMU coroutine sleep
|
|
*
|
|
* Copyright IBM, Corp. 2011
|
|
*
|
|
* Authors:
|
|
* Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
|
|
*
|
|
* This work is licensed under the terms of the GNU LGPL, version 2 or later.
|
|
* See the COPYING.LIB file in the top-level directory.
|
|
*
|
|
*/
|
|
|
|
#include "qemu/osdep.h"
|
|
#include "qemu/coroutine_int.h"
|
|
#include "qemu/timer.h"
|
|
#include "block/aio.h"
|
|
|
|
static const char *qemu_co_sleep_ns__scheduled = "qemu_co_sleep_ns";
|
|
|
|
void qemu_co_sleep_wake(QemuCoSleep *w)
|
|
{
|
|
Coroutine *co;
|
|
|
|
co = w->to_wake;
|
|
w->to_wake = NULL;
|
|
if (co) {
|
|
/* Write of schedule protected by barrier write in aio_co_schedule */
|
|
const char *scheduled = qatomic_cmpxchg(&co->scheduled,
|
|
qemu_co_sleep_ns__scheduled, NULL);
|
|
|
|
assert(scheduled == qemu_co_sleep_ns__scheduled);
|
|
aio_co_wake(co);
|
|
}
|
|
}
|
|
|
|
static void co_sleep_cb(void *opaque)
|
|
{
|
|
QemuCoSleep *w = opaque;
|
|
qemu_co_sleep_wake(w);
|
|
}
|
|
|
|
void coroutine_fn qemu_co_sleep(QemuCoSleep *w)
|
|
{
|
|
Coroutine *co = qemu_coroutine_self();
|
|
|
|
const char *scheduled = qatomic_cmpxchg(&co->scheduled, NULL,
|
|
qemu_co_sleep_ns__scheduled);
|
|
if (scheduled) {
|
|
fprintf(stderr,
|
|
"%s: Co-routine was already scheduled in '%s'\n",
|
|
__func__, scheduled);
|
|
abort();
|
|
}
|
|
|
|
w->to_wake = co;
|
|
qemu_coroutine_yield();
|
|
|
|
/* w->to_wake is cleared before resuming this coroutine. */
|
|
assert(w->to_wake == NULL);
|
|
}
|
|
|
|
void coroutine_fn qemu_co_sleep_ns_wakeable(QemuCoSleep *w,
|
|
QEMUClockType type, int64_t ns)
|
|
{
|
|
AioContext *ctx = qemu_get_current_aio_context();
|
|
QEMUTimer ts;
|
|
|
|
aio_timer_init(ctx, &ts, type, SCALE_NS, co_sleep_cb, w);
|
|
timer_mod(&ts, qemu_clock_get_ns(type) + ns);
|
|
|
|
/*
|
|
* The timer will fire in the current AiOContext, so the callback
|
|
* must happen after qemu_co_sleep yields and there is no race
|
|
* between timer_mod and qemu_co_sleep.
|
|
*/
|
|
qemu_co_sleep(w);
|
|
timer_del(&ts);
|
|
}
|