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-rw-r--r--lib/tsan/rtl/tsan_platform_mac.cc128
1 files changed, 112 insertions, 16 deletions
diff --git a/lib/tsan/rtl/tsan_platform_mac.cc b/lib/tsan/rtl/tsan_platform_mac.cc
index b72d9b07ef35..31caf37dee5a 100644
--- a/lib/tsan/rtl/tsan_platform_mac.cc
+++ b/lib/tsan/rtl/tsan_platform_mac.cc
@@ -15,8 +15,10 @@
#include "sanitizer_common/sanitizer_platform.h"
#if SANITIZER_MAC
+#include "sanitizer_common/sanitizer_atomic.h"
#include "sanitizer_common/sanitizer_common.h"
#include "sanitizer_common/sanitizer_libc.h"
+#include "sanitizer_common/sanitizer_posix.h"
#include "sanitizer_common/sanitizer_procmaps.h"
#include "tsan_platform.h"
#include "tsan_rtl.h"
@@ -40,6 +42,62 @@
namespace __tsan {
+#ifndef SANITIZER_GO
+static void *SignalSafeGetOrAllocate(uptr *dst, uptr size) {
+ atomic_uintptr_t *a = (atomic_uintptr_t *)dst;
+ void *val = (void *)atomic_load_relaxed(a);
+ atomic_signal_fence(memory_order_acquire); // Turns the previous load into
+ // acquire wrt signals.
+ if (UNLIKELY(val == nullptr)) {
+ val = (void *)internal_mmap(nullptr, size, PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANON, -1, 0);
+ CHECK(val);
+ void *cmp = nullptr;
+ if (!atomic_compare_exchange_strong(a, (uintptr_t *)&cmp, (uintptr_t)val,
+ memory_order_acq_rel)) {
+ internal_munmap(val, size);
+ val = cmp;
+ }
+ }
+ return val;
+}
+
+// On OS X, accessing TLVs via __thread or manually by using pthread_key_* is
+// problematic, because there are several places where interceptors are called
+// when TLVs are not accessible (early process startup, thread cleanup, ...).
+// The following provides a "poor man's TLV" implementation, where we use the
+// shadow memory of the pointer returned by pthread_self() to store a pointer to
+// the ThreadState object. The main thread's ThreadState pointer is stored
+// separately in a static variable, because we need to access it even before the
+// shadow memory is set up.
+static uptr main_thread_identity = 0;
+static ThreadState *main_thread_state = nullptr;
+
+ThreadState *cur_thread() {
+ ThreadState **fake_tls;
+ uptr thread_identity = (uptr)pthread_self();
+ if (thread_identity == main_thread_identity || main_thread_identity == 0) {
+ fake_tls = &main_thread_state;
+ } else {
+ fake_tls = (ThreadState **)MemToShadow(thread_identity);
+ }
+ ThreadState *thr = (ThreadState *)SignalSafeGetOrAllocate(
+ (uptr *)fake_tls, sizeof(ThreadState));
+ return thr;
+}
+
+// TODO(kuba.brecka): This is not async-signal-safe. In particular, we call
+// munmap first and then clear `fake_tls`; if we receive a signal in between,
+// handler will try to access the unmapped ThreadState.
+void cur_thread_finalize() {
+ uptr thread_identity = (uptr)pthread_self();
+ CHECK_NE(thread_identity, main_thread_identity);
+ ThreadState **fake_tls = (ThreadState **)MemToShadow(thread_identity);
+ internal_munmap(*fake_tls, sizeof(ThreadState));
+ *fake_tls = nullptr;
+}
+#endif
+
uptr GetShadowMemoryConsumption() {
return 0;
}
@@ -51,28 +109,62 @@ void WriteMemoryProfile(char *buf, uptr buf_size, uptr nthread, uptr nlive) {
}
#ifndef SANITIZER_GO
-void InitializeShadowMemory() {
- uptr shadow = (uptr)MmapFixedNoReserve(kShadowBeg,
- kShadowEnd - kShadowBeg);
- if (shadow != kShadowBeg) {
- Printf("FATAL: ThreadSanitizer can not mmap the shadow memory\n");
- Printf("FATAL: Make sure to compile with -fPIE and "
- "to link with -pie.\n");
- Die();
+void InitializeShadowMemoryPlatform() { }
+
+// On OS X, GCD worker threads are created without a call to pthread_create. We
+// need to properly register these threads with ThreadCreate and ThreadStart.
+// These threads don't have a parent thread, as they are created "spuriously".
+// We're using a libpthread API that notifies us about a newly created thread.
+// The `thread == pthread_self()` check indicates this is actually a worker
+// thread. If it's just a regular thread, this hook is called on the parent
+// thread.
+typedef void (*pthread_introspection_hook_t)(unsigned int event,
+ pthread_t thread, void *addr,
+ size_t size);
+extern "C" pthread_introspection_hook_t pthread_introspection_hook_install(
+ pthread_introspection_hook_t hook);
+static const uptr PTHREAD_INTROSPECTION_THREAD_CREATE = 1;
+static const uptr PTHREAD_INTROSPECTION_THREAD_TERMINATE = 3;
+static pthread_introspection_hook_t prev_pthread_introspection_hook;
+static void my_pthread_introspection_hook(unsigned int event, pthread_t thread,
+ void *addr, size_t size) {
+ if (event == PTHREAD_INTROSPECTION_THREAD_CREATE) {
+ if (thread == pthread_self()) {
+ // The current thread is a newly created GCD worker thread.
+ ThreadState *parent_thread_state = nullptr; // No parent.
+ int tid = ThreadCreate(parent_thread_state, 0, (uptr)thread, true);
+ CHECK_NE(tid, 0);
+ ThreadState *thr = cur_thread();
+ ThreadStart(thr, tid, GetTid());
+ }
+ } else if (event == PTHREAD_INTROSPECTION_THREAD_TERMINATE) {
+ if (thread == pthread_self()) {
+ ThreadState *thr = cur_thread();
+ if (thr->tctx) {
+ DestroyThreadState();
+ }
+ }
}
- if (common_flags()->use_madv_dontdump)
- DontDumpShadowMemory(kShadowBeg, kShadowEnd - kShadowBeg);
- DPrintf("kShadow %zx-%zx (%zuGB)\n",
- kShadowBeg, kShadowEnd,
- (kShadowEnd - kShadowBeg) >> 30);
- DPrintf("kAppMem %zx-%zx (%zuGB)\n",
- kAppMemBeg, kAppMemEnd,
- (kAppMemEnd - kAppMemBeg) >> 30);
+
+ if (prev_pthread_introspection_hook != nullptr)
+ prev_pthread_introspection_hook(event, thread, addr, size);
}
#endif
+void InitializePlatformEarly() {
+}
+
void InitializePlatform() {
DisableCoreDumperIfNecessary();
+#ifndef SANITIZER_GO
+ CheckAndProtect();
+
+ CHECK_EQ(main_thread_identity, 0);
+ main_thread_identity = (uptr)pthread_self();
+
+ prev_pthread_introspection_hook =
+ pthread_introspection_hook_install(&my_pthread_introspection_hook);
+#endif
}
#ifndef SANITIZER_GO
@@ -91,6 +183,10 @@ int call_pthread_cancel_with_cleanup(int(*fn)(void *c, void *m,
}
#endif
+bool IsGlobalVar(uptr addr) {
+ return false;
+}
+
} // namespace __tsan
#endif // SANITIZER_MAC