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qcow2: Execute run_dependent_requests() without lock

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There's no reason for run_dependent_requests() to hold s->lock, and a
later patch will require that in fact the lock is not held.

Also, before this patch, run_dependent_requests() not only does what its
name suggests, but also removes the l2meta from the list of in-flight
requests. When changing this, it becomes an one-liner, so just inline it
completely.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This commit is contained in:
Kevin Wolf 2012-12-07 18:08:48 +01:00
parent 280d373579
commit 4e95314e2b
1 changed files with 16 additions and 20 deletions
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36
block/qcow2.c
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@ -745,21 +745,6 @@ fail:
return ret;
}
static void run_dependent_requests(BDRVQcowState *s, QCowL2Meta *m)
{
/* Take the request off the list of running requests */
if (m->nb_clusters != 0) {
QLIST_REMOVE(m, next_in_flight);
}
/* Restart all dependent requests */
if (!qemu_co_queue_empty(&m->dependent_requests)) {
qemu_co_mutex_unlock(&s->lock);
qemu_co_queue_restart_all(&m->dependent_requests);
qemu_co_mutex_lock(&s->lock);
}
}
static coroutine_fn int qcow2_co_writev(BlockDriverState *bs,
int64_t sector_num,
int remaining_sectors,
@ -845,7 +830,15 @@ static coroutine_fn int qcow2_co_writev(BlockDriverState *bs,
goto fail;
}
run_dependent_requests(s, l2meta);
/* Take the request off the list of running requests */
if (l2meta->nb_clusters != 0) {
QLIST_REMOVE(l2meta, next_in_flight);
}
qemu_co_mutex_unlock(&s->lock);
qemu_co_queue_restart_all(&l2meta->dependent_requests);
qemu_co_mutex_lock(&s->lock);
g_free(l2meta);
l2meta = NULL;
}
@ -858,13 +851,16 @@ static coroutine_fn int qcow2_co_writev(BlockDriverState *bs,
ret = 0;
fail:
qemu_co_mutex_unlock(&s->lock);
if (l2meta != NULL) {
run_dependent_requests(s, l2meta);
if (l2meta->nb_clusters != 0) {
QLIST_REMOVE(l2meta, next_in_flight);
}
qemu_co_queue_restart_all(&l2meta->dependent_requests);
g_free(l2meta);
}
qemu_co_mutex_unlock(&s->lock);
qemu_iovec_destroy(&hd_qiov);
qemu_vfree(cluster_data);
trace_qcow2_writev_done_req(qemu_coroutine_self(), ret);
@ -1152,7 +1148,7 @@ static int preallocate(BlockDriverState *bs)
/* There are no dependent requests, but we need to remove our request
* from the list of in-flight requests */
if (meta != NULL) {
run_dependent_requests(bs->opaque, meta);
QLIST_REMOVE(meta, next_in_flight);
}
/* TODO Preallocate data if requested */