Fix Map Race by Moving Locking closer to the Write
@@ -217,11 +217,6 @@ func (ts *TargetSet) UpdateProviders(p map[string]TargetProvider) {
}
func (ts *TargetSet) updateProviders(ctx context.Context, providers map[string]TargetProvider) {
- // Lock for the entire time. This may mean up to 5 seconds until the full initial set
- // is retrieved and applied.
- // We could release earlier with some tweaks, but this is easier to reason about.
- ts.mtx.Lock()
- defer ts.mtx.Unlock()
// Stop all previous target providers of the target set.
if ts.cancelProviders != nil {
@@ -233,7 +228,9 @@ func (ts *TargetSet) updateProviders(ctx context.Context, providers map[string]T
// (Re-)create a fresh tgroups map to not keep stale targets around. We
// will retrieve all targets below anyway, so cleaning up everything is
// safe and doesn't inflict any additional cost.
+ ts.mtx.Lock()
ts.tgroups = map[string]*config.TargetGroup{}
+ ts.mtx.Unlock()
for name, prov := range providers {
wg.Add(1)
@@ -292,9 +289,6 @@ func (ts *TargetSet) updateProviders(ctx context.Context, providers map[string]T
// update handles a target group update from a target provider identified by the name.
func (ts *TargetSet) update(name string, tgroup *config.TargetGroup) {
- ts.mtx.Lock()
- defer ts.mtx.Unlock()
-
ts.setTargetGroup(name, tgroup)
select {
@@ -304,6 +298,9 @@ func (ts *TargetSet) update(name string, tgroup *config.TargetGroup) {
}
func (ts *TargetSet) setTargetGroup(name string, tg *config.TargetGroup) {
+ ts.mtx.Lock()
+ defer ts.mtx.Unlock()
+
if tg == nil {
return
}
