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coroutine-sleep: replace QemuCoSleepState pointer with struct in the API

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Right now, users of qemu_co_sleep_ns_wakeable are simply passing
a pointer to QemuCoSleepState by reference to the function.  But
QemuCoSleepState really is just a Coroutine*; making the
content of the struct public is just as efficient and lets us
skip the user_state_pointer indirection.

Since the usage is changed, take the occasion to rename the
struct to QemuCoSleep.

Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 20210517100548.28806-6-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This commit is contained in:
Paolo Bonzini 2021-05-17 12:05:47 +02:00 committed by Stefan Hajnoczi
parent 1485f0c24c
commit 29a6ea24eb
4 changed files with 40 additions and 44 deletions
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8
block/block-copy.c
View File

@ -50,7 +50,7 @@ typedef struct BlockCopyCallState {
/* State */
int ret;
bool finished;
QemuCoSleepState *sleep_state;
QemuCoSleep sleep;
bool cancelled;
/* OUT parameters */
@ -625,8 +625,8 @@ block_copy_dirty_clusters(BlockCopyCallState *call_state)
if (ns > 0) {
block_copy_task_end(task, -EAGAIN);
g_free(task);
qemu_co_sleep_ns_wakeable(QEMU_CLOCK_REALTIME, ns,
&call_state->sleep_state);
qemu_co_sleep_ns_wakeable(&call_state->sleep,
QEMU_CLOCK_REALTIME, ns);
continue;
}
}
@ -674,7 +674,7 @@ out:
void block_copy_kick(BlockCopyCallState *call_state)
{
qemu_co_sleep_wake(call_state->sleep_state);
qemu_co_sleep_wake(&call_state->sleep);
}
/*

10
block/nbd.c
View File

@ -116,7 +116,7 @@ typedef struct BDRVNBDState {
CoQueue free_sema;
Coroutine *connection_co;
Coroutine *teardown_co;
QemuCoSleepState *connection_co_sleep_ns_state;
QemuCoSleep reconnect_sleep;
bool drained;
bool wait_drained_end;
int in_flight;
@ -289,7 +289,7 @@ static void coroutine_fn nbd_client_co_drain_begin(BlockDriverState *bs)
BDRVNBDState *s = (BDRVNBDState *)bs->opaque;
s->drained = true;
qemu_co_sleep_wake(s->connection_co_sleep_ns_state);
qemu_co_sleep_wake(&s->reconnect_sleep);
nbd_co_establish_connection_cancel(bs, false);
@ -328,7 +328,7 @@ static void nbd_teardown_connection(BlockDriverState *bs)
s->state = NBD_CLIENT_QUIT;
if (s->connection_co) {
qemu_co_sleep_wake(s->connection_co_sleep_ns_state);
qemu_co_sleep_wake(&s->reconnect_sleep);
nbd_co_establish_connection_cancel(bs, true);
}
if (qemu_in_coroutine()) {
@ -685,8 +685,8 @@ static coroutine_fn void nbd_co_reconnect_loop(BDRVNBDState *s)
}
bdrv_inc_in_flight(s->bs);
} else {
qemu_co_sleep_ns_wakeable(QEMU_CLOCK_REALTIME, timeout,
&s->connection_co_sleep_ns_state);
qemu_co_sleep_ns_wakeable(&s->reconnect_sleep,
QEMU_CLOCK_REALTIME, timeout);
if (s->drained) {
continue;
}

23
include/qemu/coroutine.h
View File

@ -291,21 +291,22 @@ void qemu_co_rwlock_wrlock(CoRwlock *lock);
*/
void qemu_co_rwlock_unlock(CoRwlock *lock);
typedef struct QemuCoSleepState QemuCoSleepState;
typedef struct QemuCoSleep {
Coroutine *to_wake;
} QemuCoSleep;
/**
* Yield the coroutine for a given duration. During this yield, @sleep_state
* 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.
* Yield the coroutine for a given duration. Initializes @w so that,
* during this yield, it can be passed to qemu_co_sleep_wake() to
* terminate the sleep.
*/
void coroutine_fn qemu_co_sleep_ns_wakeable(QEMUClockType type, int64_t ns,
QemuCoSleepState **sleep_state);
void coroutine_fn qemu_co_sleep_ns_wakeable(QemuCoSleep *w,
QEMUClockType type, int64_t ns);
static inline void coroutine_fn qemu_co_sleep_ns(QEMUClockType type, int64_t ns)
{
QemuCoSleepState *unused = NULL;
qemu_co_sleep_ns_wakeable(type, ns, &unused);
QemuCoSleep w = { 0 };
qemu_co_sleep_ns_wakeable(&w, type, ns);
}
/**
@ -314,7 +315,7 @@ static inline void coroutine_fn qemu_co_sleep_ns(QEMUClockType type, int64_t ns)
* 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);
void qemu_co_sleep_wake(QemuCoSleep *w);
/**
* Yield until a file descriptor becomes readable

43
util/qemu-coroutine-sleep.c
View File

@ -19,42 +19,37 @@
static const char *qemu_co_sleep_ns__scheduled = "qemu_co_sleep_ns";
struct QemuCoSleepState {
Coroutine *co;
QemuCoSleepState **user_state_pointer;
};
void qemu_co_sleep_wake(QemuCoSleepState *sleep_state)
void qemu_co_sleep_wake(QemuCoSleep *w)
{
if (sleep_state) {
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(&sleep_state->co->scheduled,
const char *scheduled = qatomic_cmpxchg(&co->scheduled,
qemu_co_sleep_ns__scheduled, NULL);
assert(scheduled == qemu_co_sleep_ns__scheduled);
*sleep_state->user_state_pointer = NULL;
aio_co_wake(sleep_state->co);
aio_co_wake(co);
}
}
static void co_sleep_cb(void *opaque)
{
QemuCoSleepState **sleep_state = opaque;
qemu_co_sleep_wake(*sleep_state);
QemuCoSleep *w = opaque;
qemu_co_sleep_wake(w);
}
void coroutine_fn qemu_co_sleep_ns_wakeable(QEMUClockType type, int64_t ns,
QemuCoSleepState **sleep_state)
void coroutine_fn qemu_co_sleep_ns_wakeable(QemuCoSleep *w,
QEMUClockType type, int64_t ns)
{
Coroutine *co = qemu_coroutine_self();
AioContext *ctx = qemu_get_current_aio_context();
QEMUTimer ts;
QemuCoSleepState state = {
.co = qemu_coroutine_self(),
.user_state_pointer = sleep_state,
};
const char *scheduled = qatomic_cmpxchg(&state.co->scheduled, NULL,
qemu_co_sleep_ns__scheduled);
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",
@ -62,12 +57,12 @@ void coroutine_fn qemu_co_sleep_ns_wakeable(QEMUClockType type, int64_t ns,
abort();
}
aio_timer_init(ctx, &ts, type, SCALE_NS, co_sleep_cb, sleep_state);
*sleep_state = &state;
w->to_wake = co;
aio_timer_init(ctx, &ts, type, SCALE_NS, co_sleep_cb, w),
timer_mod(&ts, qemu_clock_get_ns(type) + ns);
qemu_coroutine_yield();
timer_del(&ts);
/* qemu_co_sleep_wake clears *sleep_state before resuming this coroutine. */
assert(*sleep_state == NULL);
/* w->to_wake is cleared before resuming this coroutine. */
assert(w->to_wake == NULL);
}