On Thu, 04/20 14:00, Paolo Bonzini wrote:
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> ---
> block/block-backend.c | 1 +
> block/throttle-groups.c | 11 +++++++++--
> include/sysemu/block-backend.h | 7 ++-----
> 3 files changed, 12 insertions(+), 7 deletions(-)
>
> diff --git a/block/block-backend.c b/block/block-backend.c
> index 915ccc5..a37d74d 100644
> --- a/block/block-backend.c
> +++ b/block/block-backend.c
> @@ -163,6 +163,7 @@ BlockBackend *blk_new(uint64_t perm, uint64_t shared_perm)
> blk->shared_perm = shared_perm;
> blk_set_enable_write_cache(blk, true);
>
> + qemu_co_mutex_init(&blk->public.reqs_lock);
> qemu_co_queue_init(&blk->public.throttled_reqs[0]);
> qemu_co_queue_init(&blk->public.throttled_reqs[1]);
>
> diff --git a/block/throttle-groups.c b/block/throttle-groups.c
> index d66bf62..695d28d 100644
> --- a/block/throttle-groups.c
> +++ b/block/throttle-groups.c
> @@ -268,8 +268,13 @@ static bool throttle_group_schedule_timer(BlockBackend *blk, bool is_write)
> static bool throttle_group_co_restart_queue(BlockBackend *blk, bool is_write)
> {
> BlockBackendPublic *blkp = blk_get_public(blk);
> + bool ret;
>
> - return qemu_co_queue_next(&blkp->throttled_reqs[is_write]);
> + qemu_co_mutex_lock(&blkp->reqs_lock);
> + ret = qemu_co_queue_next(&blkp->throttled_reqs[is_write]);
> + qemu_co_mutex_unlock(&blkp->reqs_lock);
> +
> + return ret;
> }
>
> /* Look for the next pending I/O request and schedule it.
> @@ -338,7 +343,9 @@ void coroutine_fn throttle_group_co_io_limits_intercept(BlockBackend *blk,
> if (must_wait || blkp->pending_reqs[is_write]) {
> blkp->pending_reqs[is_write]++;
> qemu_mutex_unlock(&tg->lock);
> - qemu_co_queue_wait(&blkp->throttled_reqs[is_write], NULL);
> + qemu_co_mutex_lock(&blkp->reqs_lock);
> + qemu_co_queue_wait(&blkp->throttled_reqs[is_write], &blkp->reqs_lock);
> + qemu_co_mutex_unlock(&blkp->reqs_lock);
> qemu_mutex_lock(&tg->lock);
> blkp->pending_reqs[is_write]--;
> }
> diff --git a/include/sysemu/block-backend.h b/include/sysemu/block-backend.h
> index 87a43b0..e9529fb 100644
> --- a/include/sysemu/block-backend.h
> +++ b/include/sysemu/block-backend.h
> @@ -72,11 +72,8 @@ typedef struct BlockDevOps {
> * fields that must be public. This is in particular for QLIST_ENTRY() and
> * friends so that BlockBackends can be kept in lists outside block-backend.c */
> typedef struct BlockBackendPublic {
> - /* I/O throttling has its own locking, but also some fields are
> - * protected by the AioContext lock.
> - */
> -
> - /* Protected by AioContext lock. */
> + /* reqs_lock protects the CoQueues for throttled requests. */
> + CoMutex reqs_lock;
Bikeshedding: will it be more readable if it's called throttled_reqs_lock or
throttled_lock?
Fam
> CoQueue throttled_reqs[2];
>
> /* Nonzero if the I/O limits are currently being ignored; generally
> --
> 2.9.3
>
>
>