opt: use unsafe.Add to avoid race panic

go.mod

@@ -1,10 +1,17 @@
 module github.com/cloudwego/localsession
 
-go 1.16
+go 1.17
 
 require (
 	github.com/bytedance/gopkg v0.0.0-20230728082804-614d0af6619b
-	github.com/modern-go/gls v0.0.0-20220109145502-612d0167dce5
-	github.com/modern-go/reflect2 v1.0.2 // indirect
+	github.com/modern-go/reflect2 v1.0.2
 	github.com/stretchr/testify v1.7.0
 )
+
+require (
+	github.com/davecgh/go-spew v1.1.0 // indirect
+	github.com/pmezard/go-difflib v1.0.0 // indirect
+	golang.org/x/net v0.0.0-20221014081412-f15817d10f9b // indirect
+	golang.org/x/text v0.3.7 // indirect
+	gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c // indirect
+)

go.sum

@@ -2,8 +2,6 @@ github.com/bytedance/gopkg v0.0.0-20230728082804-614d0af6619b h1:R6PWoQtxEMpWJPH
 github.com/bytedance/gopkg v0.0.0-20230728082804-614d0af6619b/go.mod h1:FtQG3YbQG9L/91pbKSw787yBQPutC+457AvDW77fgUQ=
 github.com/davecgh/go-spew v1.1.0 h1:ZDRjVQ15GmhC3fiQ8ni8+OwkZQO4DARzQgrnXU1Liz8=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
-github.com/modern-go/gls v0.0.0-20220109145502-612d0167dce5 h1:uiS4zKYKJVj5F3ID+5iylfKPsEQmBEOucSD9Vgmn0i0=
-github.com/modern-go/gls v0.0.0-20220109145502-612d0167dce5/go.mod h1:I8AX+yW//L8Hshx6+a1m3bYkwXkpsVjA2795vP4f4oQ=
 github.com/modern-go/reflect2 v1.0.2 h1:xBagoLtFs94CBntxluKeaWgTMpvLxC4ur3nMaC9Gz0M=
 github.com/modern-go/reflect2 v1.0.2/go.mod h1:yWuevngMOJpCy52FWWMvUC8ws7m/LJsjYzDa0/r8luk=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=

internal/goid/goid.go

@@ -0,0 +1,45 @@
+// Copyright 2023 CloudWeGo Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//	http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// Copyright 2016 Huan Du. All rights reserved.
+// Use of this source code is governed by a MIT
+// license that can be found in the LICENSE file.
+
+package goid
+
+import (
+	"unsafe"
+
+	"github.com/modern-go/reflect2"
+)
+
+// offset for go1.4
+var goidOffset uintptr = 128
+
+func init() {
+	gType := reflect2.TypeByName("runtime.g").(reflect2.StructType)
+	if gType == nil {
+		panic("failed to get runtime.g type")
+	}
+	goidField := gType.FieldByName("goid")
+	goidOffset = goidField.Offset()
+}
+
+// GoID returns the goroutine id of current goroutine
+func GoID() int64 {
+	p_goid := (*int64)(unsafe.Add(unsafe.Pointer(getg()), goidOffset))
+	return *p_goid
+}
+
+func getg() uintptr

internal/goid/goid_386.s

@@ -0,0 +1,27 @@
+// Copyright 2023 CloudWeGo Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//	http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// Copyright 2016 Huan Du. All rights reserved.
+// Use of this source code is governed by a MIT
+// license that can be found in the LICENSE file.
+
+#include "go_asm.h"
+#include "go_tls.h"
+#include "textflag.h"
+
+TEXT ·getg(SB), NOSPLIT, $0-4
+    get_tls(CX)
+    MOVL    g(CX), AX
+    MOVL    AX, ret+0(FP)
+    RET

internal/goid/goid_amd64.s

@@ -0,0 +1,27 @@
+// Copyright 2023 CloudWeGo Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//	http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// Copyright 2016 Huan Du. All rights reserved.
+// Use of this source code is governed by a MIT
+// license that can be found in the LICENSE file.
+
+#include "textflag.h"
+#include "go_tls.h"
+
+TEXT ·getg(SB), NOSPLIT, $0-8
+    get_tls(CX)
+    MOVQ    g(CX), AX
+    MOVQ    AX, ret+0(FP)
+    RET
+

internal/goid/goid_amd64p32.s

@@ -0,0 +1,19 @@
+// Copyright 2023 CloudWeGo Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//	http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// Copyright 2016 Huan Du. All rights reserved.
+// Use of this source code is governed by a MIT
+// license that can be found in the LICENSE file.
+
+#include "goid_amd64.s"

internal/goid/goid_arm.s

@@ -0,0 +1,26 @@
+// Copyright 2023 CloudWeGo Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//	http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// Copyright 2016 Huan Du. All rights reserved.
+// Use of this source code is governed by a MIT
+// license that can be found in the LICENSE file.
+
+#include "go_asm.h"
+#include "textflag.h"
+
+TEXT ·getg(SB), NOSPLIT, $0-4
+    MOVW    g, R8
+    MOVW    R8, ret+0(FP)
+    RET
+

internal/goid/goid_arm64.s

@@ -0,0 +1,26 @@
+//// Copyright 2023 CloudWeGo Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//	http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// Copyright 2016 Huan Du. All rights reserved.
+// Use of this source code is governed by a MIT
+// license that can be found in the LICENSE file.
+
+#include "go_asm.h"
+#include "textflag.h"
+
+TEXT ·getg(SB), NOSPLIT, $0-8
+    MOVD    g, R8
+    MOVD    R8, ret+0(FP)
+    RET
+

internal/goid/goid_riscv64.s

@@ -0,0 +1,25 @@
+//// Copyright 2023 CloudWeGo Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//	http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// Copyright 2016 Huan Du. All rights reserved.
+// Use of this source code is governed by a MIT
+// license that can be found in the LICENSE file.
+
+#include "go_asm.h"
+#include "textflag.h"
+
+TEXT ·getg(SB), NOSPLIT, $0-8
+    MOV    g, A0
+    MOV    A0, ret+0(FP)
+    RET

internal/goid/goid_test.go

@@ -0,0 +1,70 @@
+// Copyright 2023 CloudWeGo Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//	http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// Copyright 2016 Huan Du. All rights reserved.
+// Use of this source code is governed by a MIT
+// license that can be found in the LICENSE file.
+
+package goid
+
+import (
+	"fmt"
+	"runtime"
+	"strings"
+	"sync"
+	"testing"
+	_ "unsafe"
+)
+
+func TestGoID(t *testing.T) {
+	var wg sync.WaitGroup
+	for i := 0; i < 5; i++ {
+		wg.Add(1)
+		go func() {
+			testGoID(t)
+			wg.Done()
+		}()
+	}
+	wg.Wait()
+}
+
+func testGoID(t *testing.T) {
+	id := GoID()
+	lines := strings.Split(stackTrace(), "\n")
+	for i, line := range lines {
+		if !strings.HasPrefix(line, fmt.Sprintf("goroutine %d ", id)) {
+			continue
+		}
+		if i+1 == len(lines) {
+			break
+		}
+		if !strings.Contains(lines[i+1], ".stackTrace") {
+			t.Errorf("there are goroutine id %d but it is not me: %s", id, lines[i+1])
+		}
+		return
+	}
+	t.Errorf("there are no goroutine %d", id)
+}
+
+func stackTrace() string {
+	var n int
+	for n = 4096; n < 16777216; n *= 2 {
+		buf := make([]byte, n)
+		ret := runtime.Stack(buf, true)
+		if ret != n {
+			return string(buf[:ret])
+		}
+	}
+	panic(n)
+}

stubs.go

@@ -17,12 +17,12 @@ import (
 	"strconv"
 	_ "unsafe"
 
-	"github.com/modern-go/gls"
+	"github.com/cloudwego/localsession/internal/goid"
 )
 
 //go:nocheckptr
 func goID() uint64 {
-	return uint64(gls.GoID())
+	return uint64(goid.GoID())
 }
 
 type labelMap map[string]string
@@ -49,7 +49,7 @@ func transmitSessionID(id SessionID) {
 			}
 		}
 	}
-	
+
 	n[Pprof_Label_Session_ID] = strconv.FormatInt(int64(id), 10)
 	setPprofLabel(&n)
 }
@@ -73,7 +73,7 @@ func getSessionID() (SessionID, bool) {
 func clearSessionID() {
 	m := getPproLabel()
 	if m == nil {
-		return 
+		return
 	}
 	if _, ok := (*m)[Pprof_Label_Session_ID]; !ok {
 		return