Dan Willemsen | ebae302 | 2017-01-13 23:01:08 -0800 | [diff] [blame] | 1 | // Copyright 2016 The Go Authors. All rights reserved. |
| 2 | // Use of this source code is governed by a BSD-style |
| 3 | // license that can be found in the LICENSE file. |
| 4 | |
| 5 | package main |
| 6 | |
| 7 | // This program failed when run under the C/C++ ThreadSanitizer. The |
| 8 | // TSAN library was not keeping track of whether signals should be |
| 9 | // delivered on the alternate signal stack, and the Go signal handler |
| 10 | // was not preserving callee-saved registers from C callers. |
| 11 | |
| 12 | /* |
| 13 | #cgo CFLAGS: -g -fsanitize=thread |
| 14 | #cgo LDFLAGS: -g -fsanitize=thread |
| 15 | |
| 16 | #include <stdlib.h> |
| 17 | #include <sys/time.h> |
| 18 | |
| 19 | void spin() { |
| 20 | size_t n; |
| 21 | struct timeval tvstart, tvnow; |
| 22 | int diff; |
| 23 | void *prev = NULL, *cur; |
| 24 | |
| 25 | gettimeofday(&tvstart, NULL); |
| 26 | for (n = 0; n < 1<<20; n++) { |
| 27 | cur = malloc(n); |
| 28 | free(prev); |
| 29 | prev = cur; |
| 30 | |
| 31 | gettimeofday(&tvnow, NULL); |
| 32 | diff = (tvnow.tv_sec - tvstart.tv_sec) * 1000 * 1000 + (tvnow.tv_usec - tvstart.tv_usec); |
| 33 | |
| 34 | // Profile frequency is 100Hz so we should definitely |
| 35 | // get a signal in 50 milliseconds. |
| 36 | if (diff > 50 * 1000) { |
| 37 | break; |
| 38 | } |
| 39 | } |
| 40 | |
| 41 | free(prev); |
| 42 | } |
| 43 | */ |
| 44 | import "C" |
| 45 | |
| 46 | import ( |
| 47 | "io/ioutil" |
| 48 | "runtime/pprof" |
| 49 | "time" |
| 50 | ) |
| 51 | |
| 52 | func goSpin() { |
| 53 | start := time.Now() |
| 54 | for n := 0; n < 1<<20; n++ { |
| 55 | _ = make([]byte, n) |
| 56 | if time.Since(start) > 50*time.Millisecond { |
| 57 | break |
| 58 | } |
| 59 | } |
| 60 | } |
| 61 | |
| 62 | func main() { |
| 63 | pprof.StartCPUProfile(ioutil.Discard) |
| 64 | go C.spin() |
| 65 | goSpin() |
| 66 | pprof.StopCPUProfile() |
| 67 | } |