internal/vscgo: convert pprof to json

Adds `vscgo dump-pprof` and `vscgo serve-pprof` to support a custom profile renderer. Ideally `dump-pprof` would be sufficient. Unfortunately, `serve-pprof` is necessary (AFAIK) to work around profiles that are too large to fit within a NodeJS Buffer (when converted to JSON). Fixes #3573. Change-Id: I0767ff02912852e0cd4bec5745c79ff50f2d3b38 Reviewed-on: https://go-review.googlesource.com/c/vscode-go/+/621516 Reviewed-by: Hongxiang Jiang <[email protected]> kokoro-CI: kokoro <[email protected]> Reviewed-by: Hyang-Ah Hana Kim <[email protected]> Commit-Queue: Ethan Reesor <[email protected]>
golang · Oct 25, 2024 · 866878e · 866878e
1 parent 4457dbf
commit 866878e
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Showing 6 changed files with 207 additions and 11 deletions.
diff --git a/extension/go.mod b/extension/go.mod
@@ -7,6 +7,8 @@ require (
 	github.com/google/go-cmp v0.6.0
 )
 
+require github.com/google/pprof v0.0.0-20240727154555-813a5fbdbec8 // indirect
+
 require (
 	golang.org/x/mod v0.21.0
 	golang.org/x/sys v0.26.0 // indirect

diff --git a/extension/go.sum b/extension/go.sum
@@ -1,5 +1,7 @@
 github.com/google/go-cmp v0.6.0 h1:ofyhxvXcZhMsU5ulbFiLKl/XBFqE1GSq7atu8tAmTRI=
 github.com/google/go-cmp v0.6.0/go.mod h1:17dUlkBOakJ0+DkrSSNjCkIjxS6bF9zb3elmeNGIjoY=
+github.com/google/pprof v0.0.0-20240727154555-813a5fbdbec8 h1:FKHo8hFI3A+7w0aUQuYXQ+6EN5stWmeY/AZqtM8xk9k=
+github.com/google/pprof v0.0.0-20240727154555-813a5fbdbec8/go.mod h1:K1liHPHnj73Fdn/EKuT8nrFqBihUSKXoLYU0BuatOYo=
 golang.org/x/mod v0.21.0 h1:vvrHzRwRfVKSiLrG+d4FMl/Qi4ukBCE6kZlTUkDYRT0=
 golang.org/x/mod v0.21.0/go.mod h1:6SkKJ3Xj0I0BrPOZoBy3bdMptDDU9oJrpohJ3eWZ1fY=
 golang.org/x/sys v0.26.0 h1:KHjCJyddX0LoSTb3J+vWpupP9p0oznkqVk/IfjymZbo=

diff --git a/go.mod b/go.mod
@@ -4,7 +4,6 @@ go 1.23.1
 
 require golang.org/x/telemetry v0.0.0-20241004145657-5eebfecbdf1f
 
-require (
-	golang.org/x/sync v0.8.0 // indirect
-	golang.org/x/sys v0.26.0 // indirect
-)
+require github.com/google/pprof v0.0.0-20240727154555-813a5fbdbec8
+
+require golang.org/x/sys v0.26.0 // indirect
diff --git a/go.sum b/go.sum
@@ -1,10 +1,6 @@
-golang.org/x/sync v0.8.0 h1:3NFvSEYkUoMifnESzZl15y791HH1qU2xm6eCJU5ZPXQ=
-golang.org/x/sync v0.8.0/go.mod h1:Czt+wKu1gCyEFDUtn0jG5QVvpJ6rzVqr5aXyt9drQfk=
-golang.org/x/sys v0.22.0 h1:RI27ohtqKCnwULzJLqkv897zojh5/DwS/ENaMzUOaWI=
-golang.org/x/sys v0.22.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
+github.com/google/pprof v0.0.0-20240727154555-813a5fbdbec8 h1:FKHo8hFI3A+7w0aUQuYXQ+6EN5stWmeY/AZqtM8xk9k=
+github.com/google/pprof v0.0.0-20240727154555-813a5fbdbec8/go.mod h1:K1liHPHnj73Fdn/EKuT8nrFqBihUSKXoLYU0BuatOYo=
 golang.org/x/sys v0.26.0 h1:KHjCJyddX0LoSTb3J+vWpupP9p0oznkqVk/IfjymZbo=
 golang.org/x/sys v0.26.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
-golang.org/x/telemetry v0.0.0-20240712210958-268b4a8ec2d7 h1:nU8/tAV/21mkPrCjACUeSibjhynTovgRMXc32+Y1Aec=
-golang.org/x/telemetry v0.0.0-20240712210958-268b4a8ec2d7/go.mod h1:amNmu/SBSm2GAF3X+9U2C0epLocdh+r5Z+7oMYO5cLM=
 golang.org/x/telemetry v0.0.0-20241004145657-5eebfecbdf1f h1:ZYeTr2+AUYPLt6ZdXsnUUHem8NJbgmZaHisnB21BOz0=
 golang.org/x/telemetry v0.0.0-20241004145657-5eebfecbdf1f/go.mod h1:uskmY3Y2C5OU/HAtQlc9Jq98qE2bf7H3kCPFgkab838=
diff --git a/internal/vscgo/main.go b/internal/vscgo/main.go
@@ -1,4 +1,4 @@
-// Copyright 2023 The Go Authors. All rights reserved.
+// Copyright 2024 The Go Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
@@ -43,6 +43,18 @@ func init() {
 			short: "increment telemetry counters",
 			run:   runIncCounters,
 		},
+		{
+			usage:   "dump-pprof <profile>",
+			short:   "convert a pprof profile to a JSON file",
+			hasArgs: true,
+			run:     runPprofDump,
+		},
+		{
+			usage:   "serve-pprof <addr> <profile>",
+			short:   "serve a pprof profile",
+			hasArgs: true,
+			run:     runPprofServe,
+		},
 		{
 			usage: "version",
 			short: "print version information",

diff --git a/internal/vscgo/pprof.go b/internal/vscgo/pprof.go
@@ -0,0 +1,185 @@
+// Copyright 2024 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package vscgo
+
+import (
+	"encoding/json"
+	"fmt"
+	"log"
+	"net"
+	"net/http"
+	"os"
+
+	"github.com/google/pprof/profile"
+)
+
+func runPprofDump(args []string) error {
+	if len(args) != 1 {
+		return fmt.Errorf("usage: dump-pprof <profile>")
+	}
+
+	p, err := readPprof(args[0])
+	if err != nil {
+		return err
+	}
+
+	return json.NewEncoder(os.Stdout).Encode((*Profile)(p))
+}
+
+func runPprofServe(args []string) error {
+	if len(args) != 2 {
+		return fmt.Errorf("usage: serve-pprof <addr> <profile>")
+	}
+
+	l, err := net.Listen("tcp", args[0])
+	if err != nil {
+		return err
+	}
+	defer l.Close()
+
+	p, err := readPprof(args[1])
+	if err != nil {
+		return err
+	}
+
+	err = json.NewEncoder(os.Stdout).Encode(map[string]any{
+		"Listen": l.Addr(),
+	})
+	if err != nil {
+		return err
+	}
+
+	return http.Serve(l, http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Access-Control-Allow-Origin", "*")
+		w.Header().Set("Access-Control-Allow-Methods", "GET, OPTIONS")
+		w.Header().Set("Access-Control-Allow-Headers", "Content-Type")
+
+		if r.Method == "OPTIONS" {
+			w.WriteHeader(http.StatusOK)
+			return
+		}
+
+		w.Header().Set("Content-Type", "application/json")
+		err := json.NewEncoder(w).Encode((*Profile)(p))
+		if err != nil {
+			log.Println("Error: ", err)
+		}
+	}))
+}
+
+func readPprof(arg string) (*Profile, error) {
+	f, err := os.Open(arg)
+	if err != nil {
+		return nil, err
+	}
+	defer f.Close()
+
+	p, err := profile.Parse(f)
+	if err != nil {
+		return nil, err
+	}
+
+	return (*Profile)(p), nil
+}
+
+type Profile profile.Profile
+
+func (p *Profile) MarshalJSON() ([]byte, error) {
+	q := struct {
+		SampleType        []*profile.ValueType
+		DefaultSampleType string
+		Sample            []*Sample
+		Mapping           []*profile.Mapping
+		Location          []*Location
+		Function          []*profile.Function
+		Comments          []string
+		DropFrames        string
+		KeepFrames        string
+		TimeNanos         int64
+		DurationNanos     int64
+		PeriodType        *profile.ValueType
+		Period            int64
+	}{
+		SampleType:        p.SampleType,
+		DefaultSampleType: p.DefaultSampleType,
+		Sample:            make([]*Sample, len(p.Sample)),
+		Mapping:           p.Mapping,
+		Location:          make([]*Location, len(p.Location)),
+		Function:          p.Function,
+		Comments:          p.Comments,
+		DropFrames:        p.DropFrames,
+		KeepFrames:        p.KeepFrames,
+		TimeNanos:         p.TimeNanos,
+		DurationNanos:     p.DurationNanos,
+		PeriodType:        p.PeriodType,
+		Period:            p.Period,
+	}
+	for i, s := range p.Sample {
+		q.Sample[i] = (*Sample)(s)
+	}
+	for i, l := range p.Location {
+		q.Location[i] = (*Location)(l)
+	}
+	return json.Marshal(q)
+}
+
+type Sample profile.Sample
+
+func (p *Sample) MarshalJSON() ([]byte, error) {
+	q := struct {
+		Location []uint64
+		Value    []int64
+		Label    map[string][]string
+		NumLabel map[string][]int64
+		NumUnit  map[string][]string
+	}{
+		Location: make([]uint64, len(p.Location)),
+		Value:    p.Value,
+		Label:    p.Label,
+		NumLabel: p.NumLabel,
+		NumUnit:  p.NumUnit,
+	}
+	for i, l := range p.Location {
+		q.Location[i] = l.ID
+	}
+	return json.Marshal(q)
+}
+
+type Location profile.Location
+
+func (p *Location) MarshalJSON() ([]byte, error) {
+	q := struct {
+		ID       uint64
+		Mapping  uint64
+		Address  uint64
+		Line     []Line
+		IsFolded bool
+	}{
+		ID:       p.ID,
+		Mapping:  p.Mapping.ID,
+		Address:  p.Address,
+		Line:     make([]Line, len(p.Line)),
+		IsFolded: p.IsFolded,
+	}
+	for i, l := range p.Line {
+		q.Line[i] = Line(l)
+	}
+	return json.Marshal(q)
+}
+
+type Line profile.Line
+
+func (p *Line) MarshalJSON() ([]byte, error) {
+	q := struct {
+		Function uint64
+		Line     int64
+		Column   int64
+	}{
+		Function: p.Function.ID,
+		Line:     p.Line,
+		Column:   p.Column,
+	}
+	return json.Marshal(q)
+}