| // Copyright 2023 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. | |
| //go:build unix && !android && !openbsd | |
| package main | |
| /* | |
| void callStackSwitchCallbackFromThread(void); | |
| */ | |
| import "C" | |
| import ( | |
| "fmt" | |
| "runtime/debug" | |
| ) | |
| func init() { | |
| register("StackSwitchCallback", StackSwitchCallback) | |
| } | |
| //export stackSwitchCallback | |
| func stackSwitchCallback() { | |
| // We want to trigger a bounds check on the g0 stack. To do this, we | |
| // need to call a splittable function through systemstack(). | |
| // SetGCPercent contains such a systemstack call. | |
| gogc := debug.SetGCPercent(100) | |
| debug.SetGCPercent(gogc) | |
| } | |
| // Regression test for https://go.dev/issue/62440. It should be possible for C | |
| // threads to call into Go from different stacks without crashing due to g0 | |
| // stack bounds checks. | |
| // | |
| // N.B. This is only OK for threads created in C. Threads with Go frames up the | |
| // stack must not change the stack out from under us. | |
| func StackSwitchCallback() { | |
| C.callStackSwitchCallbackFromThread() | |
| fmt.Printf("OK\n") | |
| } | |