[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

3 files changed, 13 insertions, 32 deletions

diff --git a/lib/scudo/scudo_allocator.cpp b/lib/scudo/scudo_allocator.cpp
index ce69ddf55..1d0db84a5 100644
--- a/lib/scudo/scudo_allocator.cpp
+++ b/lib/scudo/scudo_allocator.cpp
@@ -273,6 +273,8 @@ struct ScudoAllocator {
   static const uptr MaxAllowedMallocSize =
       FIRST_32_SECOND_64(2UL << 30, 1ULL << 40);
 
+  typedef ReturnNullOrDieOnFailure FailureHandler;
+
   ScudoBackendAllocator BackendAllocator;
   ScudoQuarantine AllocatorQuarantine;
 
@@ -326,7 +328,8 @@ struct ScudoAllocator {
     DeallocationTypeMismatch = Options.DeallocationTypeMismatch;
     DeleteSizeMismatch = Options.DeleteSizeMismatch;
     ZeroContents = Options.ZeroContents;
-    BackendAllocator.Init(Options.MayReturnNull, Options.ReleaseToOSIntervalMs);
+    SetAllocatorMayReturnNull(Options.MayReturnNull);
+    BackendAllocator.Init(Options.ReleaseToOSIntervalMs);
     AllocatorQuarantine.Init(
         static_cast<uptr>(Options.QuarantineSizeMb) << 20,
         static_cast<uptr>(Options.ThreadLocalQuarantineSizeKb) << 10);
@@ -354,11 +357,11 @@ struct ScudoAllocator {
       dieWithMessage("ERROR: alignment is not a power of 2\n");
     }
     if (Alignment > MaxAlignment)
-      return BackendAllocator.ReturnNullOrDieOnBadRequest();
+      return FailureHandler::OnBadRequest();
     if (Alignment < MinAlignment)
       Alignment = MinAlignment;
     if (Size >= MaxAllowedMallocSize)
-      return BackendAllocator.ReturnNullOrDieOnBadRequest();
+      return FailureHandler::OnBadRequest();
     if (Size == 0)
       Size = 1;
 
@@ -366,7 +369,7 @@ struct ScudoAllocator {
     uptr AlignedSize = (Alignment > MinAlignment) ?
         NeededSize + (Alignment - AlignedChunkHeaderSize) : NeededSize;
     if (AlignedSize >= MaxAllowedMallocSize)
-      return BackendAllocator.ReturnNullOrDieOnBadRequest();
+      return FailureHandler::OnBadRequest();
 
     // Primary and Secondary backed allocations have a different treatment. We
     // deal with alignment requirements of Primary serviced allocations here,
@@ -391,7 +394,7 @@ struct ScudoAllocator {
                                       AllocationAlignment, FromPrimary);
     }
     if (!Ptr)
-      return BackendAllocator.ReturnNullOrDieOnOOM();
+      return FailureHandler::OnOOM();
 
     // If requested, we will zero out the entire contents of the returned chunk.
     if ((ForceZeroContents || ZeroContents) && FromPrimary)
@@ -583,7 +586,7 @@ struct ScudoAllocator {
     initThreadMaybe();
     uptr Total = NMemB * Size;
     if (Size != 0 && Total / Size != NMemB)  // Overflow check
-      return BackendAllocator.ReturnNullOrDieOnBadRequest();
+      return FailureHandler::OnBadRequest();
     return allocate(Total, MinAlignment, FromMalloc, true);
   }
 
diff --git a/lib/scudo/scudo_allocator_combined.h b/lib/scudo/scudo_allocator_combined.h
index c978db55a..21c45897b 100644
--- a/lib/scudo/scudo_allocator_combined.h
+++ b/lib/scudo/scudo_allocator_combined.h
@@ -23,11 +23,10 @@ template <class PrimaryAllocator, class AllocatorCache,
     class SecondaryAllocator>
 class ScudoCombinedAllocator {
  public:
-  void Init(bool AllocatorMayReturnNull, s32 ReleaseToOSIntervalMs) {
+  void Init(s32 ReleaseToOSIntervalMs) {
     Primary.Init(ReleaseToOSIntervalMs);
-    Secondary.Init(AllocatorMayReturnNull);
+    Secondary.Init();
     Stats.Init();
-    atomic_store_relaxed(&MayReturnNull, AllocatorMayReturnNull);
   }
 
   void *Allocate(AllocatorCache *Cache, uptr Size, uptr Alignment,
@@ -37,18 +36,6 @@ class ScudoCombinedAllocator {
     return Secondary.Allocate(&Stats, Size, Alignment);
   }
 
-  void *ReturnNullOrDieOnBadRequest() {
-    if (atomic_load_relaxed(&MayReturnNull))
-      return nullptr;
-    ReportAllocatorCannotReturnNull(false);
-  }
-
-  void *ReturnNullOrDieOnOOM() {
-    if (atomic_load_relaxed(&MayReturnNull))
-      return nullptr;
-    ReportAllocatorCannotReturnNull(true);
-  }
-
   void Deallocate(AllocatorCache *Cache, void *Ptr, bool FromPrimary) {
     if (FromPrimary)
       Cache->Deallocate(&Primary, Primary.GetSizeClass(Ptr), Ptr);
@@ -78,7 +65,6 @@ class ScudoCombinedAllocator {
   PrimaryAllocator Primary;
   SecondaryAllocator Secondary;
   AllocatorGlobalStats Stats;
-  atomic_uint8_t MayReturnNull;
 };
 
 #endif  // SCUDO_ALLOCATOR_COMBINED_H_
diff --git a/lib/scudo/scudo_allocator_secondary.h b/lib/scudo/scudo_allocator_secondary.h
index 2950909b5..dbfb22565 100644
--- a/lib/scudo/scudo_allocator_secondary.h
+++ b/lib/scudo/scudo_allocator_secondary.h
@@ -24,9 +24,8 @@
 class ScudoLargeMmapAllocator {
  public:
 
-  void Init(bool AllocatorMayReturnNull) {
+  void Init() {
     PageSize = GetPageSizeCached();
-    atomic_store_relaxed(&MayReturnNull, AllocatorMayReturnNull);
   }
 
   void *Allocate(AllocatorStats *Stats, uptr Size, uptr Alignment) {
@@ -42,7 +41,7 @@ class ScudoLargeMmapAllocator {
 
     uptr MapBeg = reinterpret_cast<uptr>(MmapNoAccess(MapSize));
     if (MapBeg == ~static_cast<uptr>(0))
-      return ReturnNullOrDieOnOOM();
+      return ReturnNullOrDieOnFailure::OnOOM();
     // A page-aligned pointer is assumed after that, so check it now.
     CHECK(IsAligned(MapBeg, PageSize));
     uptr MapEnd = MapBeg + MapSize;
@@ -96,12 +95,6 @@ class ScudoLargeMmapAllocator {
     return reinterpret_cast<void *>(Ptr);
   }
 
-  void *ReturnNullOrDieOnOOM() {
-    if (atomic_load_relaxed(&MayReturnNull))
-      return nullptr;
-    ReportAllocatorCannotReturnNull(true);
-  }
-
   void Deallocate(AllocatorStats *Stats, void *Ptr) {
     SecondaryHeader *Header = getHeader(Ptr);
     {
@@ -140,7 +133,6 @@ class ScudoLargeMmapAllocator {
   const uptr HeadersSize = SecondaryHeaderSize + AlignedChunkHeaderSize;
   uptr PageSize;
   SpinMutex StatsMutex;
-  atomic_uint8_t MayReturnNull;
 };
 
 #endif  // SCUDO_ALLOCATOR_SECONDARY_H_