cmd/pprof: update vendored github.com/google/pprof

Pull in the latest published version of github.com/google/pprof
as part of the continuous process of keeping Go's dependencies
up to date. Done with:

go get github.com/google/pprof
go mod tidy
go mod vendor

For #36905.

Change-Id: I2a48e912712bc916c9d749acb1550682f919477e
Reviewed-on: https://go-review.googlesource.com/c/go/+/519657
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Auto-Submit: Dmitri Shuralyov <dmitshur@golang.org>
Run-TryBot: Dmitri Shuralyov <dmitshur@golang.org>

2 files changed, 48 insertions, 5 deletions

diff --git a/src/cmd/vendor/github.com/google/pprof/profile/encode.go b/src/cmd/vendor/github.com/google/pprof/profile/encode.go
index c8a1beb8a8..182c926b90 100644
--- a/src/cmd/vendor/github.com/google/pprof/profile/encode.go
+++ b/src/cmd/vendor/github.com/google/pprof/profile/encode.go
@@ -258,10 +258,10 @@ func (p *Profile) postDecode() error {
 		// If this a main linux kernel mapping with a relocation symbol suffix
 		// ("[kernel.kallsyms]_text"), extract said suffix.
 		// It is fairly hacky to handle at this level, but the alternatives appear even worse.
-		if strings.HasPrefix(m.File, "[kernel.kallsyms]") {
-			m.KernelRelocationSymbol = strings.ReplaceAll(m.File, "[kernel.kallsyms]", "")
+		const prefix = "[kernel.kallsyms]"
+		if strings.HasPrefix(m.File, prefix) {
+			m.KernelRelocationSymbol = m.File[len(prefix):]
 		}
-
 	}
 
 	functions := make(map[uint64]*Function, len(p.Function))
diff --git a/src/cmd/vendor/github.com/google/pprof/profile/profile.go b/src/cmd/vendor/github.com/google/pprof/profile/profile.go
index 4ec00fe7d9..60ef7e9268 100644
--- a/src/cmd/vendor/github.com/google/pprof/profile/profile.go
+++ b/src/cmd/vendor/github.com/google/pprof/profile/profile.go
@@ -72,9 +72,23 @@ type ValueType struct {
 type Sample struct {
 	Location []*Location
 	Value    []int64
-	Label    map[string][]string
+	// Label is a per-label-key map to values for string labels.
+	//
+	// In general, having multiple values for the given label key is strongly
+	// discouraged - see docs for the sample label field in profile.proto.  The
+	// main reason this unlikely state is tracked here is to make the
+	// decoding->encoding roundtrip not lossy. But we expect that the value
+	// slices present in this map are always of length 1.
+	Label map[string][]string
+	// NumLabel is a per-label-key map to values for numeric labels. See a note
+	// above on handling multiple values for a label.
 	NumLabel map[string][]int64
-	NumUnit  map[string][]string
+	// NumUnit is a per-label-key map to the unit names of corresponding numeric
+	// label values. The unit info may be missing even if the label is in
+	// NumLabel, see the docs in profile.proto for details. When the value is
+	// slice is present and not nil, its length must be equal to the length of
+	// the corresponding value slice in NumLabel.
+	NumUnit map[string][]string
 
 	locationIDX []uint64
 	labelX      []label
@@ -715,6 +729,35 @@ func (s *Sample) HasLabel(key, value string) bool {
 	return false
 }
 
+// SetNumLabel sets the specified key to the specified value for all samples in the
+// profile. "unit" is a slice that describes the units that each corresponding member
+// of "values" is measured in (e.g. bytes or seconds).  If there is no relevant
+// unit for a given value, that member of "unit" should be the empty string.
+// "unit" must either have the same length as "value", or be nil.
+func (p *Profile) SetNumLabel(key string, value []int64, unit []string) {
+	for _, sample := range p.Sample {
+		if sample.NumLabel == nil {
+			sample.NumLabel = map[string][]int64{key: value}
+		} else {
+			sample.NumLabel[key] = value
+		}
+		if sample.NumUnit == nil {
+			sample.NumUnit = map[string][]string{key: unit}
+		} else {
+			sample.NumUnit[key] = unit
+		}
+	}
+}
+
+// RemoveNumLabel removes all numerical labels associated with the specified key for all
+// samples in the profile.
+func (p *Profile) RemoveNumLabel(key string) {
+	for _, sample := range p.Sample {
+		delete(sample.NumLabel, key)
+		delete(sample.NumUnit, key)
+	}
+}
+
 // DiffBaseSample returns true if a sample belongs to the diff base and false
 // otherwise.
 func (s *Sample) DiffBaseSample() bool {