metrics: fix bug that the target is wrong (#5647)

close #5646

Signed-off-by: bufferflies <1045931706@qq.com>

Author: bufferflies

metrics/grafana/pd.json

@@ -7736,10 +7736,10 @@
           "steppedLine": false,
           "targets": [
             {
-              "expr": "sum(delta(pd_schedule_filter{k8s_cluster=\"$k8s_cluster\", tidb_cluster=\"$tidb_cluster\", store=~\"$store\", action=\"filter-source\"}[1m])) by (store, type, scope)",
+              "expr": "sum(delta(pd_schedule_filter{k8s_cluster=\"$k8s_cluster\", tidb_cluster=\"$tidb_cluster\", store=~\"$store\", action=\"filter-source\"}[1m])) by (source, type, scope)",
               "format": "time_series",
               "intervalFactor": 2,
-              "legendFormat": "{{scope}}-store-{{store}}-{{type}}",
+              "legendFormat": "{{scope}}-store-{{source}}-{{type}}",
               "metric": "pd_scheduler_event_count",
               "refId": "A",
               "step": 4
@@ -7832,10 +7832,10 @@
           "steppedLine": false,
           "targets": [
             {
-              "expr": "sum(delta(pd_schedule_filter{k8s_cluster=\"$k8s_cluster\", tidb_cluster=\"$tidb_cluster\", store=~\"$store\", action=\"filter-target\"}[1m])) by (store, type, scope)",
+              "expr": "sum(delta(pd_schedule_filter{k8s_cluster=\"$k8s_cluster\", tidb_cluster=\"$tidb_cluster\", store=~\"$store\", action=\"filter-target\"}[1m])) by (target, type, scope)",
               "format": "time_series",
               "intervalFactor": 2,
-              "legendFormat": "{{scope}}-store-{{store}}-{{type}}",
+              "legendFormat": "{{scope}}-store-{{target}}-{{type}}",
               "metric": "pd_scheduler_event_count",
               "refId": "A",
               "step": 4

server/schedule/filter/counter.go

@@ -200,7 +200,7 @@ func (c *Counter) Flush() {
 			for sourceID, count := range counters {
 				sourceIDStr := strconv.FormatUint(sourceID, 10)
 				for targetID, value := range count {
-					targetIDStr := strconv.FormatUint(sourceID, 10)
+					targetIDStr := strconv.FormatUint(targetID, 10)
 					if value > 0 {
 						filterCounter.WithLabelValues(actionName, c.scope, filterName, sourceIDStr, targetIDStr).
 							Add(float64(value))