Revert r304285, r304297.

r304285 - [sanitizer] Avoid possible deadlock in child process after fork
r304297 - [sanitizer] Trying to fix MAC buildbots after r304285

These changes create deadlock when Tcl calls pthread_create from a
pthread_atfork child handler. More info in the original review at
https://reviews.llvm.org/D33325

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@304735 91177308-0d34-0410-b5e6-96231b3b80d8

3 files changed, 94 insertions, 101 deletions

diff --git a/lib/msan/msan_allocator.cc b/lib/msan/msan_allocator.cc
index f76b01de0..1be573faa 100644
--- a/lib/msan/msan_allocator.cc
+++ b/lib/msan/msan_allocator.cc
@@ -12,6 +12,8 @@
 // MemorySanitizer allocator.
 //===----------------------------------------------------------------------===//
 
+#include "sanitizer_common/sanitizer_allocator.h"
+#include "sanitizer_common/sanitizer_allocator_interface.h"
 #include "msan.h"
 #include "msan_allocator.h"
 #include "msan_origin.h"
@@ -20,12 +22,102 @@
 
 namespace __msan {
 
+struct Metadata {
+  uptr requested_size;
+};
+
+struct MsanMapUnmapCallback {
+  void OnMap(uptr p, uptr size) const {}
+  void OnUnmap(uptr p, uptr size) const {
+    __msan_unpoison((void *)p, size);
+
+    // We are about to unmap a chunk of user memory.
+    // Mark the corresponding shadow memory as not needed.
+    uptr shadow_p = MEM_TO_SHADOW(p);
+    ReleaseMemoryPagesToOS(shadow_p, shadow_p + size);
+    if (__msan_get_track_origins()) {
+      uptr origin_p = MEM_TO_ORIGIN(p);
+      ReleaseMemoryPagesToOS(origin_p, origin_p + size);
+    }
+  }
+};
+
+#if defined(__mips64)
+  static const uptr kMaxAllowedMallocSize = 2UL << 30;
+  static const uptr kRegionSizeLog = 20;
+  static const uptr kNumRegions = SANITIZER_MMAP_RANGE_SIZE >> kRegionSizeLog;
+  typedef TwoLevelByteMap<(kNumRegions >> 12), 1 << 12> ByteMap;
+
+  struct AP32 {
+    static const uptr kSpaceBeg = 0;
+    static const u64 kSpaceSize = SANITIZER_MMAP_RANGE_SIZE;
+    static const uptr kMetadataSize = sizeof(Metadata);
+    typedef __sanitizer::CompactSizeClassMap SizeClassMap;
+    static const uptr kRegionSizeLog = __msan::kRegionSizeLog;
+    typedef __msan::ByteMap ByteMap;
+    typedef MsanMapUnmapCallback MapUnmapCallback;
+    static const uptr kFlags = 0;
+  };
+  typedef SizeClassAllocator32<AP32> PrimaryAllocator;
+#elif defined(__x86_64__)
+#if SANITIZER_LINUX && !defined(MSAN_LINUX_X86_64_OLD_MAPPING)
+  static const uptr kAllocatorSpace = 0x700000000000ULL;
+#else
+  static const uptr kAllocatorSpace = 0x600000000000ULL;
+#endif
+  static const uptr kMaxAllowedMallocSize = 8UL << 30;
+
+  struct AP64 {  // Allocator64 parameters. Deliberately using a short name.
+    static const uptr kSpaceBeg = kAllocatorSpace;
+    static const uptr kSpaceSize = 0x40000000000; // 4T.
+    static const uptr kMetadataSize = sizeof(Metadata);
+    typedef DefaultSizeClassMap SizeClassMap;
+    typedef MsanMapUnmapCallback MapUnmapCallback;
+    static const uptr kFlags = 0;
+  };
+
+  typedef SizeClassAllocator64<AP64> PrimaryAllocator;
+
+#elif defined(__powerpc64__)
+  static const uptr kMaxAllowedMallocSize = 2UL << 30;  // 2G
+
+  struct AP64 {  // Allocator64 parameters. Deliberately using a short name.
+    static const uptr kSpaceBeg = 0x300000000000;
+    static const uptr kSpaceSize = 0x020000000000; // 2T.
+    static const uptr kMetadataSize = sizeof(Metadata);
+    typedef DefaultSizeClassMap SizeClassMap;
+    typedef MsanMapUnmapCallback MapUnmapCallback;
+    static const uptr kFlags = 0;
+  };
+
+  typedef SizeClassAllocator64<AP64> PrimaryAllocator;
+#elif defined(__aarch64__)
+  static const uptr kMaxAllowedMallocSize = 2UL << 30;  // 2G
+  static const uptr kRegionSizeLog = 20;
+  static const uptr kNumRegions = SANITIZER_MMAP_RANGE_SIZE >> kRegionSizeLog;
+  typedef TwoLevelByteMap<(kNumRegions >> 12), 1 << 12> ByteMap;
+
+  struct AP32 {
+    static const uptr kSpaceBeg = 0;
+    static const u64 kSpaceSize = SANITIZER_MMAP_RANGE_SIZE;
+    static const uptr kMetadataSize = sizeof(Metadata);
+    typedef __sanitizer::CompactSizeClassMap SizeClassMap;
+    static const uptr kRegionSizeLog = __msan::kRegionSizeLog;
+    typedef __msan::ByteMap ByteMap;
+    typedef MsanMapUnmapCallback MapUnmapCallback;
+    static const uptr kFlags = 0;
+  };
+  typedef SizeClassAllocator32<AP32> PrimaryAllocator;
+#endif
+typedef SizeClassAllocatorLocalCache<PrimaryAllocator> AllocatorCache;
+typedef LargeMmapAllocator<MsanMapUnmapCallback> SecondaryAllocator;
+typedef CombinedAllocator<PrimaryAllocator, AllocatorCache,
+                          SecondaryAllocator> Allocator;
+
 static Allocator allocator;
 static AllocatorCache fallback_allocator_cache;
 static SpinMutex fallback_mutex;
 
-Allocator &get_allocator() { return allocator; }
-
 void MsanAllocatorInit() {
   allocator.Init(
       common_flags()->allocator_may_return_null,
diff --git a/lib/msan/msan_allocator.h b/lib/msan/msan_allocator.h
index abd4ea678..407942e54 100644
--- a/lib/msan/msan_allocator.h
+++ b/lib/msan/msan_allocator.h
@@ -15,106 +15,9 @@
 #define MSAN_ALLOCATOR_H
 
 #include "sanitizer_common/sanitizer_common.h"
-#include "sanitizer_common/sanitizer_allocator.h"
-#include "sanitizer_common/sanitizer_allocator_interface.h"
 
 namespace __msan {
 
-struct Metadata {
-  uptr requested_size;
-};
-
-struct MsanMapUnmapCallback {
-  void OnMap(uptr p, uptr size) const {}
-  void OnUnmap(uptr p, uptr size) const {
-    __msan_unpoison((void *)p, size);
-
-    // We are about to unmap a chunk of user memory.
-    // Mark the corresponding shadow memory as not needed.
-    uptr shadow_p = MEM_TO_SHADOW(p);
-    ReleaseMemoryPagesToOS(shadow_p, shadow_p + size);
-    if (__msan_get_track_origins()) {
-      uptr origin_p = MEM_TO_ORIGIN(p);
-      ReleaseMemoryPagesToOS(origin_p, origin_p + size);
-    }
-  }
-};
-
-#if defined(__mips64)
-  static const uptr kMaxAllowedMallocSize = 2UL << 30;
-  static const uptr kRegionSizeLog = 20;
-  static const uptr kNumRegions = SANITIZER_MMAP_RANGE_SIZE >> kRegionSizeLog;
-  typedef TwoLevelByteMap<(kNumRegions >> 12), 1 << 12> ByteMap;
-
-  struct AP32 {
-    static const uptr kSpaceBeg = 0;
-    static const u64 kSpaceSize = SANITIZER_MMAP_RANGE_SIZE;
-    static const uptr kMetadataSize = sizeof(Metadata);
-    typedef __sanitizer::CompactSizeClassMap SizeClassMap;
-    static const uptr kRegionSizeLog = __msan::kRegionSizeLog;
-    typedef __msan::ByteMap ByteMap;
-    typedef MsanMapUnmapCallback MapUnmapCallback;
-    static const uptr kFlags = 0;
-  };
-  typedef SizeClassAllocator32<AP32> PrimaryAllocator;
-#elif defined(__x86_64__)
-#if SANITIZER_LINUX && !defined(MSAN_LINUX_X86_64_OLD_MAPPING)
-  static const uptr kAllocatorSpace = 0x700000000000ULL;
-#else
-  static const uptr kAllocatorSpace = 0x600000000000ULL;
-#endif
-  static const uptr kMaxAllowedMallocSize = 8UL << 30;
-
-  struct AP64 {  // Allocator64 parameters. Deliberately using a short name.
-    static const uptr kSpaceBeg = kAllocatorSpace;
-    static const uptr kSpaceSize = 0x40000000000; // 4T.
-    static const uptr kMetadataSize = sizeof(Metadata);
-    typedef DefaultSizeClassMap SizeClassMap;
-    typedef MsanMapUnmapCallback MapUnmapCallback;
-    static const uptr kFlags = 0;
-  };
-
-  typedef SizeClassAllocator64<AP64> PrimaryAllocator;
-
-#elif defined(__powerpc64__)
-  static const uptr kMaxAllowedMallocSize = 2UL << 30;  // 2G
-
-  struct AP64 {  // Allocator64 parameters. Deliberately using a short name.
-    static const uptr kSpaceBeg = 0x300000000000;
-    static const uptr kSpaceSize = 0x020000000000; // 2T.
-    static const uptr kMetadataSize = sizeof(Metadata);
-    typedef DefaultSizeClassMap SizeClassMap;
-    typedef MsanMapUnmapCallback MapUnmapCallback;
-    static const uptr kFlags = 0;
-  };
-
-  typedef SizeClassAllocator64<AP64> PrimaryAllocator;
-#elif defined(__aarch64__)
-  static const uptr kMaxAllowedMallocSize = 2UL << 30;  // 2G
-  static const uptr kRegionSizeLog = 20;
-  static const uptr kNumRegions = SANITIZER_MMAP_RANGE_SIZE >> kRegionSizeLog;
-  typedef TwoLevelByteMap<(kNumRegions >> 12), 1 << 12> ByteMap;
-
-  struct AP32 {
-    static const uptr kSpaceBeg = 0;
-    static const u64 kSpaceSize = SANITIZER_MMAP_RANGE_SIZE;
-    static const uptr kMetadataSize = sizeof(Metadata);
-    typedef __sanitizer::CompactSizeClassMap SizeClassMap;
-    static const uptr kRegionSizeLog = __msan::kRegionSizeLog;
-    typedef __msan::ByteMap ByteMap;
-    typedef MsanMapUnmapCallback MapUnmapCallback;
-    static const uptr kFlags = 0;
-  };
-  typedef SizeClassAllocator32<AP32> PrimaryAllocator;
-#endif
-typedef SizeClassAllocatorLocalCache<PrimaryAllocator> AllocatorCache;
-typedef LargeMmapAllocator<MsanMapUnmapCallback> SecondaryAllocator;
-typedef CombinedAllocator<PrimaryAllocator, AllocatorCache,
-                          SecondaryAllocator> Allocator;
-
-
-Allocator &get_allocator();
-
 struct MsanThreadLocalMallocStorage {
   uptr quarantine_cache[16];
   // Allocator cache contains atomic_uint64_t which must be 8-byte aligned.
diff --git a/lib/msan/msan_interceptors.cc b/lib/msan/msan_interceptors.cc
index fbc2ea4fe..0f5069344 100644
--- a/lib/msan/msan_interceptors.cc
+++ b/lib/msan/msan_interceptors.cc
@@ -1201,7 +1201,6 @@ INTERCEPTOR(void *, shmat, int shmid, const void *shmaddr, int shmflg) {
 }
 
 static void BeforeFork() {
-  get_allocator().ForceLock();
   StackDepotLockAll();
   ChainedOriginDepotLockAll();
 }
@@ -1209,7 +1208,6 @@ static void BeforeFork() {
 static void AfterFork() {
   ChainedOriginDepotUnlockAll();
   StackDepotUnlockAll();
-  get_allocator().ForceUnlock();
 }
 
 INTERCEPTOR(int, fork, void) {