block: move ThrottleGroup membership to ThrottleGroupMember

This commit eliminates the 1:1 relationship between BlockBackend and
throttle group state.  Users will be able to create multiple throttle
nodes, each with its own throttle group state, in the future.  The
throttle group state cannot be per-BlockBackend anymore, it must be
per-throttle node. This is done by gathering ThrottleGroup membership
details from BlockBackendPublic into ThrottleGroupMember and refactoring
existing code to use the structure.

Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Manos Pitsidianakis <el13635@mail.ntua.gr>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

1 files changed, 3 insertions, 17 deletions

diff --git a/include/sysemu/block-backend.h b/include/sysemu/block-backend.h
index aadc733daf..c4e52a5fa3 100644
--- a/include/sysemu/block-backend.h
+++ b/include/sysemu/block-backend.h
@@ -70,24 +70,10 @@ typedef struct BlockDevOps {
 
 /* This struct is embedded in (the private) BlockBackend struct and contains
  * 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 */
+ * friends so that BlockBackends can be kept in lists outside block-backend.c
+ * */
 typedef struct BlockBackendPublic {
-    /* throttled_reqs_lock protects the CoQueues for throttled requests.  */
-    CoMutex      throttled_reqs_lock;
-    CoQueue      throttled_reqs[2];
-
-    /* Nonzero if the I/O limits are currently being ignored; generally
-     * it is zero.  Accessed with atomic operations.
-     */
-    unsigned int io_limits_disabled;
-
-    /* The following fields are protected by the ThrottleGroup lock.
-     * See the ThrottleGroup documentation for details.
-     * throttle_state tells us if I/O limits are configured. */
-    ThrottleState *throttle_state;
-    ThrottleTimers throttle_timers;
-    unsigned       pending_reqs[2];
-    QLIST_ENTRY(BlockBackendPublic) round_robin;
+    ThrottleGroupMember throttle_group_member;
 } BlockBackendPublic;
 
 BlockBackend *blk_new(uint64_t perm, uint64_t shared_perm);