Bug 605362, part 1: Allocate page-aligned shmem segments in ShmImage, to match other allocators which more honestly report address space and system mem taken by alloc. r=joe

ipc/glue/Makefile.in

@@ -89,6 +89,7 @@ CPPSRCS += \
   ProcessChild.cpp \
   RPCChannel.cpp \
   ScopedXREEmbed.cpp \
+  SharedMemory.cpp \
   Shmem.cpp \
   StringUtil.cpp \
   SyncChannel.cpp \

ipc/glue/SharedMemory.cpp

@@ -0,0 +1,57 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ * vim: sw=2 ts=8 et :
+ */
+/* ***** BEGIN LICENSE BLOCK *****
+ * Version: MPL 1.1/GPL 2.0/LGPL 2.1
+ *
+ * The contents of this file are subject to the Mozilla Public License Version
+ * 1.1 (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at:
+ * http://www.mozilla.org/MPL/
+ *
+ * Software distributed under the License is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
+ * for the specific language governing rights and limitations under the
+ * License.
+ *
+ * The Original Code is Mozilla Code.
+ *
+ * The Initial Developer of the Original Code is
+ *   The Mozilla Foundation
+ * Portions created by the Initial Developer are Copyright (C) 2010
+ * the Initial Developer. All Rights Reserved.
+ *
+ * Contributor(s):
+ *   Chris Jones <jones.chris.g@gmail.com>
+ *
+ * Alternatively, the contents of this file may be used under the terms of
+ * either the GNU General Public License Version 2 or later (the "GPL"), or
+ * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
+ * in which case the provisions of the GPL or the LGPL are applicable instead
+ * of those above. If you wish to allow use of your version of this file only
+ * under the terms of either the GPL or the LGPL, and not to allow others to
+ * use your version of this file under the terms of the MPL, indicate your
+ * decision by deleting the provisions above and replace them with the notice
+ * and other provisions required by the GPL or the LGPL. If you do not delete
+ * the provisions above, a recipient may use your version of this file under
+ * the terms of any one of the MPL, the GPL or the LGPL.
+ *
+ * ***** END LICENSE BLOCK ***** */
+
+#include <math.h>
+
+#include "mozilla/ipc/SharedMemory.h"
+
+namespace mozilla {
+namespace ipc {
+
+/*static*/ size_t
+SharedMemory::PageAlignedSize(size_t aSize)
+{
+  size_t pageSize = SystemPageSize();
+  size_t nPagesNeeded = size_t(ceil(double(aSize) / double(pageSize)));
+  return pageSize * nPagesNeeded;
+}
+
+} // namespace ipc
+} // namespace mozilla

ipc/glue/SharedMemory.h

@@ -103,6 +103,7 @@ public:
 
   static void SystemProtect(char* aAddr, size_t aSize, int aRights);
   static size_t SystemPageSize();
+  static size_t PageAlignedSize(size_t aSize);
 };
 
 } // namespace ipc

ipc/glue/Shmem.cpp

@@ -38,8 +38,6 @@
  *
  * ***** END LICENSE BLOCK ***** */
 
-#include <math.h>
-
 #include "Shmem.h"
 
 #include "ProtocolUtils.h"
@@ -196,14 +194,6 @@ DestroySegment(SharedMemory* aSegment)
     aSegment->Release();
 }
 
-static size_t
-PageAlignedSize(size_t aSize)
-{
-  size_t pageSize = SharedMemory::SystemPageSize();
-  size_t nPagesNeeded = int(ceil(double(aSize) / double(pageSize)));
-  return pageSize * nPagesNeeded;
-}
-
 
 #if defined(DEBUG)
 
@@ -401,7 +391,7 @@ Shmem::Alloc(IHadBetterBeIPDLCodeCallingThis_OtherwiseIAmADoodyhead,
   size_t pageSize = SharedMemory::SystemPageSize();
   SharedMemory* segment = nsnull;
   // |2*pageSize| is for the front and back sentinel
-  size_t segmentSize = PageAlignedSize(aNBytes + 2*pageSize);
+  size_t segmentSize = SharedMemory::PageAlignedSize(aNBytes + 2*pageSize);
 
   if (aType == SharedMemory::TYPE_BASIC)
     segment = CreateSegment(segmentSize, SharedMemoryBasic::NULLHandle());
@@ -457,7 +447,7 @@ Shmem::OpenExisting(IHadBetterBeIPDLCodeCallingThis_OtherwiseIAmADoodyhead,
   SharedMemory* segment = 0;
   size_t pageSize = SharedMemory::SystemPageSize();
   // |2*pageSize| is for the front and back sentinels
-  size_t segmentSize = PageAlignedSize(size + 2*pageSize);
+  size_t segmentSize = SharedMemory::PageAlignedSize(size + 2*pageSize);
 
   if (SharedMemory::TYPE_BASIC == type) {
     SharedMemoryBasic::Handle handle;
@@ -532,11 +522,11 @@ Shmem::Alloc(IHadBetterBeIPDLCodeCallingThis_OtherwiseIAmADoodyhead,
   SharedMemory *segment = nsnull;
 
   if (aType == SharedMemory::TYPE_BASIC)
-    segment = CreateSegment(PageAlignedSize(aNBytes + sizeof(uint32)),
+    segment = CreateSegment(SharedMemory::PageAlignedSize(aNBytes + sizeof(uint32)),
                             SharedMemoryBasic::NULLHandle());
 #ifdef MOZ_HAVE_SHAREDMEMORYSYSV
   else if (aType == SharedMemory::TYPE_SYSV)
-    segment = CreateSegment(PageAlignedSize(aNBytes + sizeof(uint32)),
+    segment = CreateSegment(SharedMemory::PageAlignedSize(aNBytes + sizeof(uint32)),
                             SharedMemorySysV::NULLHandle());
 #endif
   else
@@ -568,7 +558,7 @@ Shmem::OpenExisting(IHadBetterBeIPDLCodeCallingThis_OtherwiseIAmADoodyhead,
     return 0;
 
   SharedMemory* segment = 0;
-  size_t segmentSize = PageAlignedSize(size + sizeof(size_t));
+  size_t segmentSize = SharedMemory::PageAlignedSize(size + sizeof(size_t));
 
   if (SharedMemory::TYPE_BASIC == type) {
     SharedMemoryBasic::Handle handle;

widget/src/shared/nsShmImage.cpp

@@ -51,6 +51,8 @@
 
 #ifdef MOZ_HAVE_SHMIMAGE
 
+using namespace mozilla::ipc;
+
 // If XShm isn't available to our client, we'll try XShm once, fail,
 // set this to false and then never try again.
 static PRBool gShmAvailable = PR_TRUE;
@@ -76,7 +78,8 @@ nsShmImage::Create(const gfxIntSize& aSize,
         return nsnull;
     }
 
-    size_t size = shm->mImage->bytes_per_line * shm->mImage->height;
+    size_t size = SharedMemory::PageAlignedSize(
+        shm->mImage->bytes_per_line * shm->mImage->height);
     shm->mSegment = new SharedMemorySysV();
     if (!shm->mSegment->Create(size) || !shm->mSegment->Map(size)) {
         return nsnull;

widget/src/shared/nsShmImage.h

@@ -68,11 +68,11 @@
 class QRect;
 class QWidget;
 
-using mozilla::ipc::SharedMemorySysV;
-
 class nsShmImage {
     NS_INLINE_DECL_REFCOUNTING(nsShmImage)
 
+    typedef mozilla::ipc::SharedMemorySysV SharedMemorySysV;
+
 public:
     typedef gfxASurface::gfxImageFormat Format;