throttle: Make throttle_max_is_missing_limit() set errp

The caller does not need to set it, and this will allow us to refactor
this function later.

Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

blockdev.c

@@ -355,9 +355,7 @@ static bool check_throttle_config(ThrottleConfig *cfg, Error **errp)
         return false;
     }
 
-    if (throttle_max_is_missing_limit(cfg)) {
-        error_setg(errp, "bps_max/iops_max require corresponding"
-                         " bps/iops values");
+    if (throttle_max_is_missing_limit(cfg, errp)) {
         return false;
     }
 

include/qemu/throttle.h

@@ -110,7 +110,7 @@ bool throttle_conflicting(ThrottleConfig *cfg, Error **errp);
 
 bool throttle_is_valid(ThrottleConfig *cfg);
 
-bool throttle_max_is_missing_limit(ThrottleConfig *cfg);
+bool throttle_max_is_missing_limit(ThrottleConfig *cfg, Error **errp);
 
 void throttle_config(ThrottleState *ts,
                      ThrottleTimers *tt,

tests/test-throttle.c

@@ -338,15 +338,15 @@ static void test_max_is_missing_limit(void)
         memset(&cfg, 0, sizeof(cfg));
         cfg.buckets[i].max = 100;
         cfg.buckets[i].avg = 0;
-        g_assert(throttle_max_is_missing_limit(&cfg));
+        g_assert(throttle_max_is_missing_limit(&cfg, NULL));
 
         cfg.buckets[i].max = 0;
         cfg.buckets[i].avg = 0;
-        g_assert(!throttle_max_is_missing_limit(&cfg));
+        g_assert(!throttle_max_is_missing_limit(&cfg, NULL));
 
         cfg.buckets[i].max = 0;
         cfg.buckets[i].avg = 100;
-        g_assert(!throttle_max_is_missing_limit(&cfg));
+        g_assert(!throttle_max_is_missing_limit(&cfg, NULL));
     }
 }
 

util/throttle.c

@@ -306,13 +306,16 @@ bool throttle_is_valid(ThrottleConfig *cfg)
 
 /* check if bps_max/iops_max is used without bps/iops
  * @cfg: the throttling configuration to inspect
+ * @errp: error object
  */
-bool throttle_max_is_missing_limit(ThrottleConfig *cfg)
+bool throttle_max_is_missing_limit(ThrottleConfig *cfg, Error **errp)
 {
     int i;
 
     for (i = 0; i < BUCKETS_COUNT; i++) {
         if (cfg->buckets[i].max && !cfg->buckets[i].avg) {
+            error_setg(errp, "bps_max/iops_max require corresponding"
+                       " bps/iops values");
             return true;
         }
     }