diff options
author | Alexander Potapenko <glider@google.com> | 2014-05-13 16:17:54 +0000 |
---|---|---|
committer | Alexander Potapenko <glider@google.com> | 2014-05-13 16:17:54 +0000 |
commit | 8563d6ef39045d86b2791a7fae75fe803eff66b4 (patch) | |
tree | 451858f9902a212745e1f7e5a8b3f224ebce0baf | |
parent | b58e7f412543c2641e2bc8d087fe6836f426cb92 (diff) |
[libsanitizer] Use internal_fork() to spawn the symbolizer process.
This should fix https://code.google.com/p/thread-sanitizer/issues/detail?id=61
git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@208707 91177308-0d34-0410-b5e6-96231b3b80d8
-rw-r--r-- | lib/sanitizer_common/sanitizer_libc.h | 2 | ||||
-rw-r--r-- | lib/sanitizer_common/sanitizer_linux.cc | 4 | ||||
-rw-r--r-- | lib/sanitizer_common/sanitizer_mac.cc | 5 | ||||
-rw-r--r-- | lib/sanitizer_common/sanitizer_symbolizer_posix_libcdep.cc | 3 | ||||
-rw-r--r-- | test/tsan/pthread_atfork_deadlock.c | 31 |
5 files changed, 44 insertions, 1 deletions
diff --git a/lib/sanitizer_common/sanitizer_libc.h b/lib/sanitizer_common/sanitizer_libc.h index 0768ae16e..a9d308e38 100644 --- a/lib/sanitizer_common/sanitizer_libc.h +++ b/lib/sanitizer_common/sanitizer_libc.h @@ -91,6 +91,8 @@ uptr internal_waitpid(int pid, int *status, int options); uptr internal_getpid(); uptr internal_getppid(); +uptr internal_fork(); + // Threading uptr internal_sched_yield(); diff --git a/lib/sanitizer_common/sanitizer_linux.cc b/lib/sanitizer_common/sanitizer_linux.cc index f0daa89f0..c14232631 100644 --- a/lib/sanitizer_common/sanitizer_linux.cc +++ b/lib/sanitizer_common/sanitizer_linux.cc @@ -501,6 +501,10 @@ uptr internal_sigaltstack(const struct sigaltstack *ss, return internal_syscall(SYSCALL(sigaltstack), (uptr)ss, (uptr)oss); } +uptr internal_fork() { + return internal_syscall(SYSCALL(fork)); +} + #if SANITIZER_LINUX // Doesn't set sa_restorer, use with caution (see below). int internal_sigaction_norestorer(int signum, const void *act, void *oldact) { diff --git a/lib/sanitizer_common/sanitizer_mac.cc b/lib/sanitizer_common/sanitizer_mac.cc index 747513de5..7a4a0d586 100644 --- a/lib/sanitizer_common/sanitizer_mac.cc +++ b/lib/sanitizer_common/sanitizer_mac.cc @@ -126,6 +126,11 @@ int internal_sigaction(int signum, const void *act, void *oldact) { (struct sigaction *)act, (struct sigaction *)oldact); } +int internal_fork() { + // TODO(glider): this may call user's pthread_atfork() handlers which is bad. + return fork(); +} + // ----------------- sanitizer_common.h bool FileExists(const char *filename) { struct stat st; diff --git a/lib/sanitizer_common/sanitizer_symbolizer_posix_libcdep.cc b/lib/sanitizer_common/sanitizer_symbolizer_posix_libcdep.cc index a87bfbf1a..ca47e3c83 100644 --- a/lib/sanitizer_common/sanitizer_symbolizer_posix_libcdep.cc +++ b/lib/sanitizer_common/sanitizer_symbolizer_posix_libcdep.cc @@ -234,7 +234,8 @@ class SymbolizerProcess : public ExternalSymbolizerInterface { CHECK(infd); CHECK(outfd); - int pid = fork(); + // Real fork() may call user callbacks registered with pthread_atfork(). + int pid = internal_fork(); if (pid == -1) { // Fork() failed. internal_close(infd[0]); diff --git a/test/tsan/pthread_atfork_deadlock.c b/test/tsan/pthread_atfork_deadlock.c new file mode 100644 index 000000000..27dff46b9 --- /dev/null +++ b/test/tsan/pthread_atfork_deadlock.c @@ -0,0 +1,31 @@ +// RUN: %clang_tsan -O1 %s -o %t && not %run %t 2>&1 | FileCheck %s +// Regression test for +// https://code.google.com/p/thread-sanitizer/issues/detail?id=61 +// When the data race was reported, pthread_atfork() handler used to be +// executed which caused another race report in the same thread, which resulted +// in a deadlock. +#include <pthread.h> +#include <stdio.h> + +int glob = 0; + +void *worker(void *unused) { + glob++; + return NULL; +} + +void atfork() { + fprintf(stderr, "ATFORK\n"); + glob++; +} + +int main() { + pthread_atfork(atfork, NULL, NULL); + pthread_t t; + pthread_create(&t, NULL, worker, NULL); + glob++; + pthread_join(t, NULL); + // CHECK: ThreadSanitizer: data race + // CHECK-NOT: ATFORK + return 0; +} |