diff options
Diffstat (limited to 'src/runtime/pprof/testdata/mappingtest/main.go')
-rw-r--r-- | src/runtime/pprof/testdata/mappingtest/main.go | 108 |
1 files changed, 108 insertions, 0 deletions
diff --git a/src/runtime/pprof/testdata/mappingtest/main.go b/src/runtime/pprof/testdata/mappingtest/main.go new file mode 100644 index 0000000..484b7f9 --- /dev/null +++ b/src/runtime/pprof/testdata/mappingtest/main.go @@ -0,0 +1,108 @@ +// Copyright 2018 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. + +// This program outputs a CPU profile that includes +// both Go and Cgo stacks. This is used by the mapping info +// tests in runtime/pprof. +// +// If SETCGOTRACEBACK=1 is set, the CPU profile will includes +// PCs from C side but they will not be symbolized. +package main + +/* +#include <stdint.h> +#include <stdlib.h> + +int cpuHogCSalt1 = 0; +int cpuHogCSalt2 = 0; + +void CPUHogCFunction0(int foo) { + int i; + for (i = 0; i < 100000; i++) { + if (foo > 0) { + foo *= foo; + } else { + foo *= foo + 1; + } + cpuHogCSalt2 = foo; + } +} + +void CPUHogCFunction() { + CPUHogCFunction0(cpuHogCSalt1); +} + +struct CgoTracebackArg { + uintptr_t context; + uintptr_t sigContext; + uintptr_t *buf; + uintptr_t max; +}; + +void CollectCgoTraceback(void* parg) { + struct CgoTracebackArg* arg = (struct CgoTracebackArg*)(parg); + arg->buf[0] = (uintptr_t)(CPUHogCFunction0); + arg->buf[1] = (uintptr_t)(CPUHogCFunction); + arg->buf[2] = 0; +}; +*/ +import "C" + +import ( + "log" + "os" + "runtime" + "runtime/pprof" + "time" + "unsafe" +) + +func init() { + if v := os.Getenv("SETCGOTRACEBACK"); v == "1" { + // Collect some PCs from C-side, but don't symbolize. + runtime.SetCgoTraceback(0, unsafe.Pointer(C.CollectCgoTraceback), nil, nil) + } +} + +func main() { + go cpuHogGoFunction() + go cpuHogCFunction() + runtime.Gosched() + + if err := pprof.StartCPUProfile(os.Stdout); err != nil { + log.Fatal("can't start CPU profile: ", err) + } + time.Sleep(200 * time.Millisecond) + pprof.StopCPUProfile() + + if err := os.Stdout.Close(); err != nil { + log.Fatal("can't write CPU profile: ", err) + } +} + +var salt1 int +var salt2 int + +func cpuHogGoFunction() { + for { + foo := salt1 + for i := 0; i < 1e5; i++ { + if foo > 0 { + foo *= foo + } else { + foo *= foo + 1 + } + salt2 = foo + } + runtime.Gosched() + } +} + +func cpuHogCFunction() { + // Generates CPU profile samples including a Cgo call path. + for { + C.CPUHogCFunction() + runtime.Gosched() + } +} |