qemu-coroutine-sleep: introduce qemu_co_sleep_wake

Introduce a function to gracefully wake a coroutine sleeping in
qemu_co_sleep_ns().

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20191009084158.15614-2-vsementsov@virtuozzo.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
This commit is contained in:
Vladimir Sementsov-Ogievskiy 2019-10-09 11:41:56 +03:00 committed by Eric Blake
parent f9bec78137
commit 3d692649d1
2 changed files with 59 additions and 15 deletions

View file

@ -273,10 +273,29 @@ void qemu_co_rwlock_wrlock(CoRwlock *lock);
*/
void qemu_co_rwlock_unlock(CoRwlock *lock);
typedef struct QemuCoSleepState QemuCoSleepState;
/**
* Yield the coroutine for a given duration
* Yield the coroutine for a given duration. During this yield, @sleep_state
* (if not NULL) is set to an opaque pointer, which may be used for
* qemu_co_sleep_wake(). Be careful, the pointer is set back to zero when the
* timer fires. Don't save the obtained value to other variables and don't call
* qemu_co_sleep_wake from another aio context.
*/
void coroutine_fn qemu_co_sleep_ns(QEMUClockType type, int64_t ns);
void coroutine_fn qemu_co_sleep_ns_wakeable(QEMUClockType type, int64_t ns,
QemuCoSleepState **sleep_state);
static inline void coroutine_fn qemu_co_sleep_ns(QEMUClockType type, int64_t ns)
{
qemu_co_sleep_ns_wakeable(type, ns, NULL);
}
/**
* Wake a coroutine if it is sleeping in qemu_co_sleep_ns. The timer will be
* deleted. @sleep_state must be the variable whose address was given to
* qemu_co_sleep_ns() and should be checked to be non-NULL before calling
* qemu_co_sleep_wake().
*/
void qemu_co_sleep_wake(QemuCoSleepState *sleep_state);
/**
* Yield until a file descriptor becomes readable