diff options
-rw-r--r-- | libgo/runtime/go-callers.c | 9 | ||||
-rw-r--r-- | libgo/runtime/proc.c | 9 | ||||
-rw-r--r-- | libgo/runtime/runtime.h | 1 |
3 files changed, 19 insertions, 0 deletions
diff --git a/libgo/runtime/go-callers.c b/libgo/runtime/go-callers.c index 291dfd0d666..ae411d9c83a 100644 --- a/libgo/runtime/go-callers.c +++ b/libgo/runtime/go-callers.c @@ -11,6 +11,13 @@ #include "runtime.h" #include "array.h" +/* This is set to non-zero when calling backtrace_full. This is used + to avoid getting hanging on a recursive lock in dl_iterate_phdr on + older versions of glibc when a SIGPROF signal arrives while + collecting a backtrace. */ + +uint32 runtime_in_callers; + /* Argument passed to callback function. */ struct callers_data @@ -111,8 +118,10 @@ runtime_callers (int32 skip, Location *locbuf, int32 m) data.skip = skip + 1; data.index = 0; data.max = m; + runtime_xadd (&runtime_in_callers, 1); backtrace_full (__go_get_backtrace_state (), 0, callback, error_callback, &data); + runtime_xadd (&runtime_in_callers, -1); return data.index; } diff --git a/libgo/runtime/proc.c b/libgo/runtime/proc.c index de2a54bfa5e..47a472b6d0a 100644 --- a/libgo/runtime/proc.c +++ b/libgo/runtime/proc.c @@ -2454,6 +2454,15 @@ runtime_sigprof() return; } n = 0; + + if(runtime_atomicload(&runtime_in_callers) > 0) { + // If SIGPROF arrived while already fetching runtime + // callers we can have trouble on older systems + // because the unwind library calls dl_iterate_phdr + // which was not recursive in the past. + traceback = false; + } + if(traceback) { n = runtime_callers(0, prof.locbuf, nelem(prof.locbuf)); for(i = 0; i < n; i++) diff --git a/libgo/runtime/runtime.h b/libgo/runtime/runtime.h index e82e83231e6..b9a1686d385 100644 --- a/libgo/runtime/runtime.h +++ b/libgo/runtime/runtime.h @@ -776,6 +776,7 @@ extern struct backtrace_state *__go_get_backtrace_state(void); extern _Bool __go_file_line(uintptr, String*, String*, intgo *); extern byte* runtime_progname(); extern void runtime_main(void*); +extern uint32 runtime_in_callers; int32 getproccount(void); |