runtime/pprof: propagate profile labels into profile proto

Profile labels added by the user using pprof.Do, if present will
be in a *labelMap stored in the unsafe.Pointer 'tag' field of
the profile map entry. This change extracts the labels from the tag
field and writes them to the profile proto.

Change-Id: Ic40fdc58b66e993ca91d5d5effe0e04ffbb5bc46
Reviewed-on: https://go-review.googlesource.com/39613
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>

diff --git a/src/runtime/pprof/pprof_test.go b/src/runtime/pprof/pprof_test.go
index b4696762aa524c900be569d82210693a9f26dce1..5d8da0eace98c88c6075bcf661835ae0e13017b2 100644 (file)
--- a/src/runtime/pprof/pprof_test.go
+++ b/src/runtime/pprof/pprof_test.go
@@ -8,6 +8,7 @@ package pprof
 
 import (
        "bytes"
+       "context"
        "fmt"
        "internal/testenv"
        "math/big"
@@ -85,7 +86,7 @@ func TestCPUProfileMultithreaded(t *testing.T) {
        })
 }
 
-func parseProfile(t *testing.T, valBytes []byte, f func(uintptr, []uintptr)) {
+func parseProfile(t *testing.T, valBytes []byte, f func(uintptr, []uintptr, map[string][]string)) {
        p, err := profile.Parse(bytes.NewReader(valBytes))
        if err != nil {
                t.Fatal(err)
@@ -96,7 +97,7 @@ func parseProfile(t *testing.T, valBytes []byte, f func(uintptr, []uintptr)) {
                for i := range sample.Location {
                        stk[i] = uintptr(sample.Location[i].Address)
                }
-               f(count, stk)
+               f(count, stk, sample.Label)
        }
 }
 
@@ -164,6 +165,15 @@ func testCPUProfile(t *testing.T, need []string, f func(dur time.Duration)) {
        t.FailNow()
 }
 
+func contains(slice []string, s string) bool {
+       for i := range slice {
+               if slice[i] == s {
+                       return true
+               }
+       }
+       return false
+}
+
 func profileOk(t *testing.T, need []string, prof bytes.Buffer, duration time.Duration) (ok bool) {
        ok = true
 
@@ -171,7 +181,7 @@ func profileOk(t *testing.T, need []string, prof bytes.Buffer, duration time.Dur
        have := make([]uintptr, len(need))
        var samples uintptr
        var buf bytes.Buffer
-       parseProfile(t, prof.Bytes(), func(count uintptr, stk []uintptr) {
+       parseProfile(t, prof.Bytes(), func(count uintptr, stk []uintptr, labels map[string][]string) {
                fmt.Fprintf(&buf, "%d:", count)
                samples += count
                for _, pc := range stk {
@@ -182,6 +192,13 @@ func profileOk(t *testing.T, need []string, prof bytes.Buffer, duration time.Dur
                        }
                        fmt.Fprintf(&buf, "(%s)", f.Name())
                        for i, name := range need {
+                               if semi := strings.Index(name, ";"); semi > -1 {
+                                       kv := strings.SplitN(name[semi+1:], "=", 2)
+                                       if len(kv) != 2 || !contains(labels[kv[0]], kv[1]) {
+                                               continue
+                                       }
+                                       name = name[:semi]
+                               }
                                if strings.Contains(f.Name(), name) {
                                        have[i] += count
                                }
@@ -296,7 +313,7 @@ func TestGoroutineSwitch(t *testing.T) {
 
                // Read profile to look for entries for runtime.gogo with an attempt at a traceback.
                // The special entry
-               parseProfile(t, prof.Bytes(), func(count uintptr, stk []uintptr) {
+               parseProfile(t, prof.Bytes(), func(count uintptr, stk []uintptr, _ map[string][]string) {
                        // An entry with two frames with 'System' in its top frame
                        // exists to record a PC without a traceback. Those are okay.
                        if len(stk) == 2 {
@@ -654,3 +671,11 @@ func TestEmptyCallStack(t *testing.T) {
                t.Fatalf("got:\n\t%q\ndoes not contain:\n\t%q\n", got, lostevent)
        }
 }
+
+func TestCPUProfileLabel(t *testing.T) {
+       testCPUProfile(t, []string{"runtime/pprof.cpuHogger;key=value"}, func(dur time.Duration) {
+               Do(context.Background(), Labels("key", "value"), func(context.Context) {
+                       cpuHogger(cpuHog1, dur)
+               })
+       })
+}

diff --git a/src/runtime/pprof/proto.go b/src/runtime/pprof/proto.go
index 5a14dab1972ae74188c7caafbb1437e40ab8a75a..fd0b7c3e620f7fd5bc322134f4cc22bc8fc3450a 100644 (file)
--- a/src/runtime/pprof/proto.go
+++ b/src/runtime/pprof/proto.go
@@ -339,6 +339,15 @@ func (b *profileBuilder) build() error {
                values[0] = e.count
                values[1] = e.count * b.period
 
+               var labels func()
+               if e.tag != nil {
+                       labels = func() {
+                               for k, v := range *(*labelMap)(e.tag) {
+                                       b.pbLabel(tagSample_Label, k, v, 0)
+                               }
+                       }
+               }
+
                locs = locs[:0]
                for i, addr := range e.stk {
                        // Addresses from stack traces point to the next instruction after
@@ -353,7 +362,7 @@ func (b *profileBuilder) build() error {
                        }
                        locs = append(locs, l)
                }
-               b.pbSample(values, locs, nil)
+               b.pbSample(values, locs, labels)
        }
 
        // TODO: Anything for tagProfile_DropFrames?