coredns/plugin/metrics/registry.go
Miek Gieben 118b0c9408
plugin/metrcs: fix datarace on listeners (#2835)
This fixes a data race on the listener(s) that get started in the
metrics plugins.

It also restore pkg/uniq to its former glory and removes and state being
carried in there; this means for metrics that registry.go was to
replicate that behavior *with* locking (as pkg/uniq doesn't do, or need
that).

Also renamed uniqAddr to just u, to make it slightly shorter.

Signed-off-by: Miek Gieben <miek@miek.nl>
2019-05-18 18:34:46 +01:00

28 lines
533 B
Go

package metrics
import (
"sync"
"github.com/prometheus/client_golang/prometheus"
)
type reg struct {
sync.RWMutex
r map[string]*prometheus.Registry
}
func newReg() *reg { return &reg{r: make(map[string]*prometheus.Registry)} }
// update sets the registry if not already there and returns the input. Or it returns
// a previous set value.
func (r *reg) getOrSet(addr string, pr *prometheus.Registry) *prometheus.Registry {
r.Lock()
defer r.Unlock()
if v, ok := r.r[addr]; ok {
return v
}
r.r[addr] = pr
return pr
}