diff --git a/decoder/decoder.go b/decoder/decoder.go index 15837738..029c9e9c 100644 --- a/decoder/decoder.go +++ b/decoder/decoder.go @@ -61,8 +61,8 @@ func NewSet() (*Set, error) { }, nil } -// Decode transforms input byte field into a string according to configuration -func (s *Set) Decode(in []byte, label config.Label) ([]byte, error) { +// decode transforms input byte field into a string according to configuration +func (s *Set) decode(in []byte, label config.Label) ([]byte, error) { result := in for _, decoder := range label.Decoders { @@ -70,9 +70,7 @@ func (s *Set) Decode(in []byte, label config.Label) ([]byte, error) { return result, fmt.Errorf("unknown decoder %q", decoder.Name) } - s.mu.Lock() decoded, err := s.decoders[decoder.Name].Decode(result, decoder) - s.mu.Unlock() if err != nil { if err == ErrSkipLabelSet { return decoded, err @@ -89,6 +87,9 @@ func (s *Set) Decode(in []byte, label config.Label) ([]byte, error) { // DecodeLabels transforms eBPF map key bytes into a list of label values // according to configuration func (s *Set) DecodeLabels(in []byte, labels []config.Label) ([]string, error) { + s.mu.Lock() + defer s.mu.Unlock() + // string(in) must not be a variable to avoid allocation: // * https://github.com/golang/go/commit/f5f5a8b6209f8 if cached, ok := s.cache[string(in)]; ok { @@ -132,7 +133,7 @@ func (s *Set) decodeLabels(in []byte, labels []config.Label) ([]string, error) { size := label.Size - decoded, err := s.Decode(in[off:off+size], label) + decoded, err := s.decode(in[off:off+size], label) if err != nil { return nil, err } diff --git a/decoder/decoder_test.go b/decoder/decoder_test.go index 5871f628..d9debaa6 100644 --- a/decoder/decoder_test.go +++ b/decoder/decoder_test.go @@ -2,6 +2,7 @@ package decoder import ( "fmt" + "sync" "testing" "github.com/cloudflare/ebpf_exporter/v2/config" @@ -151,6 +152,61 @@ func TestDecodeLabels(t *testing.T) { } } +func TestConcurrency(t *testing.T) { + in := append([]byte{0x8, 0x0, 0x0, 0x0}, zeroPaddedString("bananas", 32)...) + + labels := []config.Label{ + { + Name: "number", + Size: 4, + Decoders: []config.Decoder{ + { + Name: "uint", + }, + }, + }, + { + Name: "fruit", + Size: 32, + Decoders: []config.Decoder{ + { + Name: "string", + }, + { + Name: "regexp", + Regexps: []string{ + "^bananas$", + "$is-banana-even-fruit$", + }, + }, + }, + }, + } + + s, err := NewSet() + if err != nil { + t.Fatal(err) + } + + count := 1000 + + wg := sync.WaitGroup{} + wg.Add(count) + + for i := 0; i < count; i++ { + go func() { + defer wg.Done() + + _, err := s.DecodeLabels(in, labels) + if err != nil { + t.Error(err) + } + }() + } + + wg.Wait() +} + func BenchmarkCache(b *testing.B) { in := []byte{ 0x8, 0xab, 0xce, 0xef,