throttle: Extract timers from ThrottleState into a separate structure

Group throttling will share ThrottleState between multiple bs.
As a consequence the ThrottleState will be accessed by multiple aio
context.

Timers are tied to their aio context so they must go out of the
ThrottleState structure.

This commit paves the way for each bs of a common ThrottleState to
have its own timer.

Signed-off-by: Benoit Canet <benoit.canet@nodalink.com>
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 6cf9ea96d8b32ae2f8769cead38f68a6a0c8c909.1433779731.git.berto@igalia.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

2 files changed, 25 insertions, 14 deletions

diff --git a/include/block/block_int.h b/include/block/block_int.h
index f004378d58..02b312fea9 100644
--- a/include/block/block_int.h
+++ b/include/block/block_int.h
@@ -380,6 +380,7 @@ struct BlockDriverState {
 
     /* I/O throttling */
     ThrottleState throttle_state;
+    ThrottleTimers throttle_timers;
     CoQueue      throttled_reqs[2];
     bool         io_limits_enabled;
 
diff --git a/include/qemu/throttle.h b/include/qemu/throttle.h
index b890613a9c..2c560db2f1 100644
--- a/include/qemu/throttle.h
+++ b/include/qemu/throttle.h
@@ -65,14 +65,17 @@ typedef struct ThrottleConfig {
 typedef struct ThrottleState {
     ThrottleConfig cfg;       /* configuration */
     int64_t previous_leak;    /* timestamp of the last leak done */
-    QEMUTimer * timers[2];    /* timers used to do the throttling */
+} ThrottleState;
+
+typedef struct ThrottleTimers {
+    QEMUTimer *timers[2];     /* timers used to do the throttling */
     QEMUClockType clock_type; /* the clock used */
 
     /* Callbacks */
     QEMUTimerCB *read_timer_cb;
     QEMUTimerCB *write_timer_cb;
     void *timer_opaque;
-} ThrottleState;
+} ThrottleTimers;
 
 /* operations on single leaky buckets */
 void throttle_leak_bucket(LeakyBucket *bkt, int64_t delta);
@@ -86,20 +89,23 @@ bool throttle_compute_timer(ThrottleState *ts,
                             int64_t *next_timestamp);
 
 /* init/destroy cycle */
-void throttle_init(ThrottleState *ts,
-                   AioContext *aio_context,
-                   QEMUClockType clock_type,
-                   void (read_timer)(void *),
-                   void (write_timer)(void *),
-                   void *timer_opaque);
+void throttle_init(ThrottleState *ts);
+
+void throttle_timers_init(ThrottleTimers *tt,
+                          AioContext *aio_context,
+                          QEMUClockType clock_type,
+                          QEMUTimerCB *read_timer_cb,
+                          QEMUTimerCB *write_timer_cb,
+                          void *timer_opaque);
 
-void throttle_destroy(ThrottleState *ts);
+void throttle_timers_destroy(ThrottleTimers *tt);
 
-void throttle_detach_aio_context(ThrottleState *ts);
+void throttle_timers_detach_aio_context(ThrottleTimers *tt);
 
-void throttle_attach_aio_context(ThrottleState *ts, AioContext *new_context);
+void throttle_timers_attach_aio_context(ThrottleTimers *tt,
+                                        AioContext *new_context);
 
-bool throttle_have_timer(ThrottleState *ts);
+bool throttle_timers_are_initialized(ThrottleTimers *tt);
 
 /* configuration */
 bool throttle_enabled(ThrottleConfig *cfg);
@@ -108,12 +114,16 @@ bool throttle_conflicting(ThrottleConfig *cfg);
 
 bool throttle_is_valid(ThrottleConfig *cfg);
 
-void throttle_config(ThrottleState *ts, ThrottleConfig *cfg);
+void throttle_config(ThrottleState *ts,
+                     ThrottleTimers *tt,
+                     ThrottleConfig *cfg);
 
 void throttle_get_config(ThrottleState *ts, ThrottleConfig *cfg);
 
 /* usage */
-bool throttle_schedule_timer(ThrottleState *ts, bool is_write);
+bool throttle_schedule_timer(ThrottleState *ts,
+                             ThrottleTimers *tt,
+                             bool is_write);
 
 void throttle_account(ThrottleState *ts, bool is_write, uint64_t size);