diff options
Diffstat (limited to 'src/runtime/testdata/testprogcgo/pprof.go')
-rw-r--r-- | src/runtime/testdata/testprogcgo/pprof.go | 102 |
1 files changed, 102 insertions, 0 deletions
diff --git a/src/runtime/testdata/testprogcgo/pprof.go b/src/runtime/testdata/testprogcgo/pprof.go new file mode 100644 index 0000000..3b73fa0 --- /dev/null +++ b/src/runtime/testdata/testprogcgo/pprof.go @@ -0,0 +1,102 @@ +// Copyright 2016 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. + +package main + +// Run a slow C function saving a CPU profile. + +/* +#include <stdint.h> + +int salt1; +int salt2; + +void cpuHog() { + int foo = salt1; + int i; + + for (i = 0; i < 100000; i++) { + if (foo > 0) { + foo *= foo; + } else { + foo *= foo + 1; + } + } + salt2 = foo; +} + +void cpuHog2() { +} + +static int cpuHogCount; + +struct cgoTracebackArg { + uintptr_t context; + uintptr_t sigContext; + uintptr_t* buf; + uintptr_t max; +}; + +// pprofCgoTraceback is passed to runtime.SetCgoTraceback. +// For testing purposes it pretends that all CPU hits in C code are in cpuHog. +// Issue #29034: At least 2 frames are required to verify all frames are captured +// since runtime/pprof ignores the runtime.goexit base frame if it exists. +void pprofCgoTraceback(void* parg) { + struct cgoTracebackArg* arg = (struct cgoTracebackArg*)(parg); + arg->buf[0] = (uintptr_t)(cpuHog) + 0x10; + arg->buf[1] = (uintptr_t)(cpuHog2) + 0x4; + arg->buf[2] = 0; + ++cpuHogCount; +} + +// getCpuHogCount fetches the number of times we've seen cpuHog in the +// traceback. +int getCpuHogCount() { + return cpuHogCount; +} +*/ +import "C" + +import ( + "fmt" + "os" + "runtime" + "runtime/pprof" + "time" + "unsafe" +) + +func init() { + register("CgoPprof", CgoPprof) +} + +func CgoPprof() { + runtime.SetCgoTraceback(0, unsafe.Pointer(C.pprofCgoTraceback), nil, nil) + + f, err := os.CreateTemp("", "prof") + if err != nil { + fmt.Fprintln(os.Stderr, err) + os.Exit(2) + } + + if err := pprof.StartCPUProfile(f); err != nil { + fmt.Fprintln(os.Stderr, err) + os.Exit(2) + } + + t0 := time.Now() + for C.getCpuHogCount() < 2 && time.Since(t0) < time.Second { + C.cpuHog() + } + + pprof.StopCPUProfile() + + name := f.Name() + if err := f.Close(); err != nil { + fmt.Fprintln(os.Stderr, err) + os.Exit(2) + } + + fmt.Println(name) +} |