Copyright 2014->2015

[folly.git] / folly / Malloc.h

diff --git a/folly/Malloc.h b/folly/Malloc.h
index cd426c3d077826ad36e5391b3a3e2ddb68be37e2..ca8c7c7aa9801e66563926b7b06a98c04343d10e 100644 (file)
--- a/folly/Malloc.h
+++ b/folly/Malloc.h
@@ -1,5 +1,5 @@
 /*
- * Copyright 2014 Facebook, Inc.
+ * Copyright 2015 Facebook, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -84,8 +84,6 @@ __attribute__((__weak__));
 #include <folly/Portability.h>
 #endif
 
-#include <folly/ScopeGuard.h>
-
 // for malloc_usable_size
 // NOTE: FreeBSD 9 doesn't have malloc.h.  It's defitions
 // are found in stdlib.h.
@@ -133,31 +131,23 @@ inline size_t goodMallocSize(size_t minSize) noexcept {
     return minSize;
   }
   size_t goodSize;
-  SCOPE_EXIT { assert(nallocx(goodSize, 0) == goodSize); };
   if (minSize <= 64) {
     // Choose smallest allocation to be 64 bytes - no tripping over
     // cache line boundaries, and small string optimization takes care
     // of short strings anyway.
-    return goodSize = 64;
-  }
-  if (minSize <= 512) {
+    goodSize = 64;
+  } else if (minSize <= 512) {
     // Round up to the next multiple of 64; we don't want to trip over
     // cache line boundaries.
-    return goodSize = (minSize + 63) & ~size_t(63);
-  }
-  if (minSize <= 3584) {
-    // Round up to the next multiple of 256.  For some size classes jemalloc
-    // will additionally round up to the nearest multiple of 512, hence the
-    // nallocx() call.
-    return goodSize = nallocx((minSize + 255) & ~size_t(255), 0);
-  }
-  if (minSize <= 4072 * 1024) {
-    // Round up to the next multiple of 4KB
-    return goodSize = (minSize + 4095) & ~size_t(4095);
+    goodSize = (minSize + 63) & ~size_t(63);
+  } else {
+    // Boundaries between size classes depend on numerious factors, some of
+    // which can even be modified at run-time. Determine the good allocation
+    // size by calling nallocx() directly.
+    goodSize = nallocx(minSize, 0);
   }
-  // Holy Moly
-  // Round up to the next multiple of 4MB
-  return goodSize = (minSize + 4194303) & ~size_t(4194303);
+  assert(nallocx(goodSize, 0) == goodSize);
+  return goodSize;
 }
 
 // We always request "good" sizes for allocation, so jemalloc can