Merge pull request #1112 from xuyang2/process-name-linux

[process][linux] get name from /proc/(pid)/comm

v3/process/process_linux.go

@@ -82,7 +82,7 @@ func (p *Process) PpidWithContext(ctx context.Context) (int32, error) {
 
 func (p *Process) NameWithContext(ctx context.Context) (string, error) {
 	if p.name == "" {
-		if err := p.fillFromStatusWithContext(ctx); err != nil {
+		if err := p.fillNameWithContext(ctx); err != nil {
 			return "", err
 		}
 	}
@@ -800,6 +800,28 @@ func (p *Process) fillFromStatmWithContext(ctx context.Context) (*MemoryInfoStat
 	return memInfo, memInfoEx, nil
 }
 
+// Get name from /proc/(pid)/comm or /proc/(pid)/status
+func (p *Process) fillNameWithContext(ctx context.Context) error {
+	err := p.fillFromCommWithContext(ctx)
+	if err == nil && p.name != "" && len(p.name) < 15 {
+		return nil
+	}
+	return p.fillFromStatusWithContext(ctx)
+}
+
+// Get name from /proc/(pid)/comm
+func (p *Process) fillFromCommWithContext(ctx context.Context) error {
+	pid := p.Pid
+	statPath := common.HostProc(strconv.Itoa(int(pid)), "comm")
+	contents, err := ioutil.ReadFile(statPath)
+	if err != nil {
+		return err
+	}
+
+	p.name = strings.TrimSuffix(string(contents), "\n")
+	return nil
+}
+
 // Get various status from /proc/(pid)/status
 func (p *Process) fillFromStatusWithContext(ctx context.Context) error {
 	pid := p.Pid

v3/process/process_linux_test.go

@@ -3,10 +3,10 @@
 package process
 
 import (
-	"os"
 	"context"
 	"fmt"
 	"io/ioutil"
+	"os"
 	"strconv"
 	"strings"
 	"testing"
@@ -94,6 +94,28 @@ func Test_Process_splitProcStat_fromFile(t *testing.T) {
 	}
 }
 
+func Test_fillFromCommWithContext(t *testing.T) {
+	pids, err := ioutil.ReadDir("testdata/linux/")
+	if err != nil {
+		t.Error(err)
+	}
+	f := common.MockEnv("HOST_PROC", "testdata/linux")
+	defer f()
+	for _, pid := range pids {
+		pid, err := strconv.ParseInt(pid.Name(), 0, 32)
+		if err != nil {
+			continue
+		}
+		if _, err := os.Stat(fmt.Sprintf("testdata/linux/%d/status", pid)); err != nil {
+			continue
+		}
+		p, _ := NewProcess(int32(pid))
+		if err := p.fillFromCommWithContext(context.Background()); err != nil {
+			t.Error(err)
+		}
+	}
+}
+
 func Test_fillFromStatusWithContext(t *testing.T) {
 	pids, err := ioutil.ReadDir("testdata/linux/")
 	if err != nil {
@@ -116,6 +138,26 @@ func Test_fillFromStatusWithContext(t *testing.T) {
 	}
 }
 
+func Benchmark_fillFromCommWithContext(b *testing.B) {
+	f := common.MockEnv("HOST_PROC", "testdata/linux")
+	defer f()
+	pid := 1060
+	p, _ := NewProcess(int32(pid))
+	for i := 0; i < b.N; i++ {
+		p.fillFromCommWithContext(context.Background())
+	}
+}
+
+func Benchmark_fillFromStatusWithContext(b *testing.B) {
+	f := common.MockEnv("HOST_PROC", "testdata/linux")
+	defer f()
+	pid := 1060
+	p, _ := NewProcess(int32(pid))
+	for i := 0; i < b.N; i++ {
+		p.fillFromStatusWithContext(context.Background())
+	}
+}
+
 func Test_fillFromTIDStatWithContext_lx_brandz(t *testing.T) {
 	pids, err := ioutil.ReadDir("testdata/lx_brandz/")
 	if err != nil {

v3/process/testdata/linux/1/comm

@@ -0,0 +1 @@
+ksoftirqd/0

v3/process/testdata/linux/1060/comm

@@ -0,0 +1 @@
+server

v3/process/testdata/linux/68927/comm

@@ -0,0 +1 @@
+test(cmd).sh