[Sanitizers] Move cached allocator_may_return_null flag to sanitizer_allocator

Summary:
Move cached allocator_may_return_null flag to sanitizer_allocator.cc and
provide API to consolidate and unify the behavior of all specific allocators.

Make all sanitizers using CombinedAllocator to follow
AllocatorReturnNullOrDieOnOOM() rules to behave the same way when OOM
happens.

When OOM happens, turn allocator_out_of_memory flag on regardless of
allocator_may_return_null flag value (it used to not to be set when
allocator_may_return_null == true).

release_to_os_interval_ms and rss_limit_exceeded will likely be moved to
sanitizer_allocator.cc too (later).

Reviewers: eugenis

Subscribers: srhines, kubamracek, llvm-commits

Differential Revision: https://reviews.llvm.org/D34310

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@305858 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 9 insertions, 26 deletions

diff --git a/lib/sanitizer_common/sanitizer_allocator_secondary.h b/lib/sanitizer_common/sanitizer_allocator_secondary.h
index 2c69f47ec..261dfb5e1 100644
--- a/lib/sanitizer_common/sanitizer_allocator_secondary.h
+++ b/lib/sanitizer_common/sanitizer_allocator_secondary.h
@@ -17,17 +17,19 @@
 // This class can (de)allocate only large chunks of memory using mmap/unmap.
 // The main purpose of this allocator is to cover large and rare allocation
 // sizes not covered by more efficient allocators (e.g. SizeClassAllocator64).
-template <class MapUnmapCallback = NoOpMapUnmapCallback>
+template <class MapUnmapCallback = NoOpMapUnmapCallback,
+          class FailureHandlerT = ReturnNullOrDieOnFailure>
 class LargeMmapAllocator {
  public:
-  void InitLinkerInitialized(bool may_return_null) {
+  typedef FailureHandlerT FailureHandler;
+
+  void InitLinkerInitialized() {
     page_size_ = GetPageSizeCached();
-    atomic_store(&may_return_null_, may_return_null, memory_order_relaxed);
   }
 
-  void Init(bool may_return_null) {
+  void Init() {
     internal_memset(this, 0, sizeof(*this));
-    InitLinkerInitialized(may_return_null);
+    InitLinkerInitialized();
   }
 
   void *Allocate(AllocatorStats *stat, uptr size, uptr alignment) {
@@ -37,11 +39,11 @@ class LargeMmapAllocator {
       map_size += alignment;
     // Overflow.
     if (map_size < size)
-      return ReturnNullOrDieOnBadRequest();
+      return FailureHandler::OnBadRequest();
     uptr map_beg = reinterpret_cast<uptr>(
         MmapOrDieOnFatalError(map_size, "LargeMmapAllocator"));
     if (!map_beg)
-      return ReturnNullOrDieOnOOM();
+      return FailureHandler::OnOOM();
     CHECK(IsAligned(map_beg, page_size_));
     MapUnmapCallback().OnMap(map_beg, map_size);
     uptr map_end = map_beg + map_size;
@@ -75,24 +77,6 @@ class LargeMmapAllocator {
     return reinterpret_cast<void*>(res);
   }
 
-  bool MayReturnNull() const {
-    return atomic_load(&may_return_null_, memory_order_acquire);
-  }
-
-  void *ReturnNullOrDieOnBadRequest() {
-    if (MayReturnNull()) return nullptr;
-    ReportAllocatorCannotReturnNull(false);
-  }
-
-  void *ReturnNullOrDieOnOOM() {
-    if (MayReturnNull()) return nullptr;
-    ReportAllocatorCannotReturnNull(true);
-  }
-
-  void SetMayReturnNull(bool may_return_null) {
-    atomic_store(&may_return_null_, may_return_null, memory_order_release);
-  }
-
   void Deallocate(AllocatorStats *stat, void *p) {
     Header *h = GetHeader(p);
     {
@@ -278,7 +262,6 @@ class LargeMmapAllocator {
   struct Stats {
     uptr n_allocs, n_frees, currently_allocated, max_allocated, by_size_log[64];
   } stats;
-  atomic_uint8_t may_return_null_;
   SpinMutex mutex_;
 };