block-copy: let ratelimit handle a speed of 0

Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Message-Id: <20210614081130.22134-3-eesposit@redhat.com>
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>

block/block-copy.c

@@ -114,7 +114,6 @@ typedef struct BlockCopyState {
 
     SharedResource *mem;
 
-    uint64_t speed;
     RateLimit rate_limit;
 } BlockCopyState;
 
@@ -647,21 +646,19 @@ block_copy_dirty_clusters(BlockCopyCallState *call_state)
             task->copy_range = false;
         }
 
-        if (s->speed) {
-            if (!call_state->ignore_ratelimit) {
-                uint64_t ns = ratelimit_calculate_delay(&s->rate_limit, 0);
-                if (ns > 0) {
-                    block_copy_task_end(task, -EAGAIN);
-                    g_free(task);
-                    qemu_co_sleep_ns_wakeable(&call_state->sleep,
-                                              QEMU_CLOCK_REALTIME, ns);
-                    continue;
-                }
+        if (!call_state->ignore_ratelimit) {
+            uint64_t ns = ratelimit_calculate_delay(&s->rate_limit, 0);
+            if (ns > 0) {
+                block_copy_task_end(task, -EAGAIN);
+                g_free(task);
+                qemu_co_sleep_ns_wakeable(&call_state->sleep,
+                                          QEMU_CLOCK_REALTIME, ns);
+                continue;
             }
-
-            ratelimit_calculate_delay(&s->rate_limit, task->bytes);
         }
 
+        ratelimit_calculate_delay(&s->rate_limit, task->bytes);
+
         trace_block_copy_process(s, task->offset);
 
         co_get_from_shres(s->mem, task->bytes);
@@ -853,10 +850,7 @@ void block_copy_set_skip_unallocated(BlockCopyState *s, bool skip)
 
 void block_copy_set_speed(BlockCopyState *s, uint64_t speed)
 {
-    s->speed = speed;
-    if (speed > 0) {
-        ratelimit_set_speed(&s->rate_limit, speed, BLOCK_COPY_SLICE_TIME);
-    }
+    ratelimit_set_speed(&s->rate_limit, speed, BLOCK_COPY_SLICE_TIME);
 
     /*
      * Note: it's good to kick all call states from here, but it should be done