[Qemu-devel] [PATCH] throttle: Remove throttle_group_lock/unlock()

[Qemu-devel] [PATCH] throttle: Remove throttle_group_lock/unlock()

[Alberto Garcia]

The group throttling code was always meant to handle its locking
internally. However, bdrv_swap() was touching the ThrottleGroup
structure directly and therefore needed an API for that.

Now that bdrv_swap() no longer exists there's no need for the
throttle_group_lock() API anymore.

Signed-off-by: Alberto Garcia <berto@igalia.com>
---
 block/throttle-groups.c         | 31 +------------------------------
 include/block/throttle-groups.h |  3 ---
 2 files changed, 1 insertion(+), 33 deletions(-)

diff --git a/block/throttle-groups.c b/block/throttle-groups.c
index 1abc6fc..f70c31a 100644
--- a/block/throttle-groups.c
+++ b/block/throttle-groups.c
@@ -33,8 +33,7 @@
  * its own locking.
  *
  * This locking is however handled internally in this file, so it's
- * mostly transparent to outside users (but see the documentation in
- * throttle_groups_lock()).
+ * transparent to outside users.
  *
  * The whole ThrottleGroup structure is private and invisible to
  * outside users, that only use it through its ThrottleState.
@@ -465,34 +464,6 @@ void throttle_group_unregister_bs(BlockDriverState *bs)
     bs->throttle_state = NULL;
 }
 
-/* Acquire the lock of this throttling group.
- *
- * You won't normally need to use this. None of the functions from the
- * ThrottleGroup API require you to acquire the lock since all of them
- * deal with it internally.
- *
- * This should only be used in exceptional cases when you want to
- * access the protected fields of a BlockDriverState directly
- * (e.g. bdrv_swap()).
- *
- * @bs: a BlockDriverState that is member of the group
- */
-void throttle_group_lock(BlockDriverState *bs)
-{
-    ThrottleGroup *tg = container_of(bs->throttle_state, ThrottleGroup, ts);
-    qemu_mutex_lock(&tg->lock);
-}
-
-/* Release the lock of this throttling group.
- *
- * See the comments in throttle_group_lock().
- */
-void throttle_group_unlock(BlockDriverState *bs)
-{
-    ThrottleGroup *tg = container_of(bs->throttle_state, ThrottleGroup, ts);
-    qemu_mutex_unlock(&tg->lock);
-}
-
 static void throttle_groups_init(void)
 {
     qemu_mutex_init(&throttle_groups_lock);
diff --git a/include/block/throttle-groups.h b/include/block/throttle-groups.h
index fab113f..322139a 100644
--- a/include/block/throttle-groups.h
+++ b/include/block/throttle-groups.h
@@ -40,7 +40,4 @@ void coroutine_fn throttle_group_co_io_limits_intercept(BlockDriverState *bs,
                                                         unsigned int bytes,
                                                         bool is_write);
 
-void throttle_group_lock(BlockDriverState *bs);
-void throttle_group_unlock(BlockDriverState *bs);
-
 #endif
-- 
2.6.1

Re: [Qemu-devel] [PATCH] throttle: Remove throttle_group_lock/unlock()

[Kevin Wolf]

Am 21.10.2015 um 20:36 hat Alberto Garcia geschrieben:
> The group throttling code was always meant to handle its locking
> internally. However, bdrv_swap() was touching the ThrottleGroup
> structure directly and therefore needed an API for that.
> 
> Now that bdrv_swap() no longer exists there's no need for the
> throttle_group_lock() API anymore.
> 
> Signed-off-by: Alberto Garcia <berto@igalia.com>

Thanks, applied to the block branch.

Kevin