1 files changed, 24 insertions, 19 deletions
diff --git a/third_party/tcmalloc/chromium/src/system-alloc.cc b/third_party/tcmalloc/chromium/src/system-alloc.cc
index 21d9b43..29bed80 100644
--- a/third_party/tcmalloc/chromium/src/system-alloc.cc
+++ b/third_party/tcmalloc/chromium/src/system-alloc.cc
@@ -78,7 +78,7 @@ union MemoryAligner {
   void*  p;
   double d;
   size_t s;
-};
+} CACHELINE_ALIGNED;
 
 static SpinLock spinlock(SpinLock::LINKER_INITIALIZED);
 
@@ -150,6 +150,10 @@ bool RegisterSystemAllocator(SysAllocator *a, int priority) {
 
 void* SbrkSysAllocator::Alloc(size_t size, size_t *actual_size,
                               size_t alignment) {
+#ifndef HAVE_SBRK
+  failed_ = true;
+  return NULL;
+#else
   // Check if we should use sbrk allocation.
   // FLAGS_malloc_skip_sbrk starts out as false (its uninitialized
   // state) and eventually gets initialized to the specified value.  Note
@@ -164,16 +168,16 @@ void* SbrkSysAllocator::Alloc(size_t size, size_t *actual_size,
   // a strict check here
   if (static_cast<ptrdiff_t>(size + alignment) < 0) return NULL;
 
-  // could theoretically return the "extra" bytes here, but this
-  // is simple and correct.
-  if (actual_size) {
-    *actual_size = size;
-  }
-
   // This doesn't overflow because TCMalloc_SystemAlloc has already
   // tested for overflow at the alignment boundary.
   size = ((size + alignment - 1) / alignment) * alignment;
 
+  // "actual_size" indicates that the bytes from the returned pointer
+  // p up to and including (p + actual_size - 1) have been allocated.
+  if (actual_size) {
+    *actual_size = size;
+  }
+
   // Check that we we're not asking for so much more memory that we'd
   // wrap around the end of the virtual address space.  (This seems
   // like something sbrk() should check for us, and indeed opensolaris
@@ -216,6 +220,7 @@ void* SbrkSysAllocator::Alloc(size_t size, size_t *actual_size,
     ptr += alignment - (ptr & (alignment-1));
   }
   return reinterpret_cast<void*>(ptr);
+#endif  // HAVE_SBRK
 }
 
 void SbrkSysAllocator::DumpStats(TCMalloc_Printer* printer) {
@@ -238,12 +243,6 @@ void* MmapSysAllocator::Alloc(size_t size, size_t *actual_size,
     return NULL;
   }
 
-  // could theoretically return the "extra" bytes here, but this
-  // is simple and correct.
-  if (actual_size) {
-    *actual_size = size;
-  }
-
   // Enforce page alignment
   if (pagesize == 0) pagesize = getpagesize();
   if (alignment < pagesize) alignment = pagesize;
@@ -253,6 +252,12 @@ void* MmapSysAllocator::Alloc(size_t size, size_t *actual_size,
   }
   size = aligned_size;
 
+  // "actual_size" indicates that the bytes from the returned pointer
+  // p up to and including (p + actual_size - 1) have been allocated.
+  if (actual_size) {
+    *actual_size = size;
+  }
+
   // Ask for extra memory if alignment > pagesize
   size_t extra = 0;
   if (alignment > pagesize) {
@@ -328,12 +333,6 @@ void* DevMemSysAllocator::Alloc(size_t size, size_t *actual_size,
     initialized = true;
   }
 
-  // could theoretically return the "extra" bytes here, but this
-  // is simple and correct.
-  if (actual_size) {
-    *actual_size = size;
-  }
-
   // Enforce page alignment
   if (pagesize == 0) pagesize = getpagesize();
   if (alignment < pagesize) alignment = pagesize;
@@ -343,6 +342,12 @@ void* DevMemSysAllocator::Alloc(size_t size, size_t *actual_size,
   }
   size = aligned_size;
 
+  // "actual_size" indicates that the bytes from the returned pointer
+  // p up to and including (p + actual_size - 1) have been allocated.
+  if (actual_size) {
+    *actual_size = size;
+  }
+
   // Ask for extra memory if alignment > pagesize
   size_t extra = 0;
   if (alignment > pagesize) {