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-rw-r--r--pkg/goid/BUILD24
-rw-r--r--pkg/goid/empty_test.go22
-rw-r--r--pkg/goid/goid.go24
-rw-r--r--pkg/goid/goid_amd64.s21
-rw-r--r--pkg/goid/goid_race.go25
-rw-r--r--pkg/goid/goid_test.go74
-rw-r--r--pkg/goid/goid_unsafe.go64
7 files changed, 254 insertions, 0 deletions
diff --git a/pkg/goid/BUILD b/pkg/goid/BUILD
new file mode 100644
index 000000000..ea8d2422c
--- /dev/null
+++ b/pkg/goid/BUILD
@@ -0,0 +1,24 @@
+load("//tools:defs.bzl", "go_library", "go_test")
+
+package(licenses = ["notice"])
+
+go_library(
+ name = "goid",
+ srcs = [
+ "goid.go",
+ "goid_amd64.s",
+ "goid_race.go",
+ "goid_unsafe.go",
+ ],
+ visibility = ["//visibility:public"],
+)
+
+go_test(
+ name = "goid_test",
+ size = "small",
+ srcs = [
+ "empty_test.go",
+ "goid_test.go",
+ ],
+ library = ":goid",
+)
diff --git a/pkg/goid/empty_test.go b/pkg/goid/empty_test.go
new file mode 100644
index 000000000..c0a4b17ab
--- /dev/null
+++ b/pkg/goid/empty_test.go
@@ -0,0 +1,22 @@
+// Copyright 2020 The gVisor 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.
+
+// +build !race
+
+package goid
+
+import "testing"
+
+// TestNothing exists to make the build system happy.
+func TestNothing(t *testing.T) {}
diff --git a/pkg/goid/goid.go b/pkg/goid/goid.go
new file mode 100644
index 000000000..39df30031
--- /dev/null
+++ b/pkg/goid/goid.go
@@ -0,0 +1,24 @@
+// Copyright 2020 The gVisor 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.
+
+// +build !race
+
+// Package goid provides access to the ID of the current goroutine in
+// race/gotsan builds.
+package goid
+
+// Get returns the ID of the current goroutine.
+func Get() int64 {
+ panic("unimplemented for non-race builds")
+}
diff --git a/pkg/goid/goid_amd64.s b/pkg/goid/goid_amd64.s
new file mode 100644
index 000000000..d9f5cd2a3
--- /dev/null
+++ b/pkg/goid/goid_amd64.s
@@ -0,0 +1,21 @@
+// Copyright 2020 The gVisor 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.
+
+#include "textflag.h"
+
+// func getg() *g
+TEXT ·getg(SB),NOSPLIT,$0-8
+ MOVQ (TLS), R14
+ MOVQ R14, ret+0(FP)
+ RET
diff --git a/pkg/goid/goid_race.go b/pkg/goid/goid_race.go
new file mode 100644
index 000000000..1766beaee
--- /dev/null
+++ b/pkg/goid/goid_race.go
@@ -0,0 +1,25 @@
+// Copyright 2020 The gVisor 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.
+
+// Only available in race/gotsan builds.
+// +build race
+
+// Package goid provides access to the ID of the current goroutine in
+// race/gotsan builds.
+package goid
+
+// Get returns the ID of the current goroutine.
+func Get() int64 {
+ return goid()
+}
diff --git a/pkg/goid/goid_test.go b/pkg/goid/goid_test.go
new file mode 100644
index 000000000..31970ce79
--- /dev/null
+++ b/pkg/goid/goid_test.go
@@ -0,0 +1,74 @@
+// Copyright 2020 The gVisor 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.
+
+// +build race
+
+package goid
+
+import (
+ "runtime"
+ "sync"
+ "testing"
+)
+
+func TestInitialGoID(t *testing.T) {
+ const max = 10000
+ if id := goid(); id < 0 || id > max {
+ t.Errorf("got goid = %d, want 0 < goid <= %d", id, max)
+ }
+}
+
+// TestGoIDSquence verifies that goid returns values which could plausibly be
+// goroutine IDs. If this test breaks or becomes flaky, the structs in
+// goid_unsafe.go may need to be updated.
+func TestGoIDSquence(t *testing.T) {
+ // Goroutine IDs are cached by each P.
+ runtime.GOMAXPROCS(1)
+
+ // Fill any holes in lower range.
+ for i := 0; i < 50; i++ {
+ var wg sync.WaitGroup
+ wg.Add(1)
+ go func() {
+ wg.Done()
+
+ // Leak the goroutine to prevent the ID from being
+ // reused.
+ select {}
+ }()
+ wg.Wait()
+ }
+
+ id := goid()
+ for i := 0; i < 100; i++ {
+ var (
+ newID int64
+ wg sync.WaitGroup
+ )
+ wg.Add(1)
+ go func() {
+ newID = goid()
+ wg.Done()
+
+ // Leak the goroutine to prevent the ID from being
+ // reused.
+ select {}
+ }()
+ wg.Wait()
+ if max := id + 100; newID <= id || newID > max {
+ t.Errorf("unexpected goroutine ID pattern, got goid = %d, want %d < goid <= %d (previous = %d)", newID, id, max, id)
+ }
+ id = newID
+ }
+}
diff --git a/pkg/goid/goid_unsafe.go b/pkg/goid/goid_unsafe.go
new file mode 100644
index 000000000..ded8004dd
--- /dev/null
+++ b/pkg/goid/goid_unsafe.go
@@ -0,0 +1,64 @@
+// Copyright 2020 The gVisor 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.
+
+package goid
+
+// Structs from Go runtime. These may change in the future and require
+// updating. These structs are currently the same on both AMD64 and ARM64,
+// but may diverge in the future.
+
+type stack struct {
+ lo uintptr
+ hi uintptr
+}
+
+type gobuf struct {
+ sp uintptr
+ pc uintptr
+ g uintptr
+ ctxt uintptr
+ ret uint64
+ lr uintptr
+ bp uintptr
+}
+
+type g struct {
+ stack stack
+ stackguard0 uintptr
+ stackguard1 uintptr
+
+ _panic uintptr
+ _defer uintptr
+ m uintptr
+ sched gobuf
+ syscallsp uintptr
+ syscallpc uintptr
+ stktopsp uintptr
+ param uintptr
+ atomicstatus uint32
+ stackLock uint32
+ goid int64
+
+ // More fields...
+ //
+ // We only use goid and the fields before it are only listed to
+ // calculate the correct offset.
+}
+
+func getg() *g
+
+// goid returns the ID of the current goroutine.
+func goid() int64 {
+ return getg().goid
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-23 14:06:37 +0000