8007074: SIGSEGV at ParMarkBitMap::verify_clear() Summary: Replace the broken large pages implementation on Linux. New flag: -XX:+UseTransparentHugePages - Linux specific flag to turn on transparent huge page hinting with madvise(..., MAP_HUGETLB). Changed behavior: -XX:+UseLargePages - tries to use -XX:+UseTransparentHugePages before trying other large pages implementations (on Linux). Changed behavior: -XX:+UseHugeTLBFS - Use upfront allocation of Large Pages instead of using the broken implementation to dynamically committing large pages. Changed behavior: -XX:LargePageSizeInBytes - Turned off the ability to use this flag on Linux and provides warning to user if set to a value different than the OS chosen large page size. Changed behavior: Setting no large page size - Now defaults to use -XX:UseTransparentHugePages if the OS supports it. Previously, -XX:+UseHugeTLBFS was chosen if the OS was configured to use large pages. Reviewed-by: tschatzl, dcubed, brutisso

--- a/src/os/windows/vm/os_windows.cpp	Sun Aug 25 21:21:18 2013 -0400
+++ b/src/os/windows/vm/os_windows.cpp	Fri Aug 16 13:22:32 2013 +0200
@@ -3156,7 +3156,12 @@
   return true;
 }
 
-char* os::reserve_memory_special(size_t bytes, char* addr, bool exec) {
+char* os::reserve_memory_special(size_t bytes, size_t alignment, char* addr, bool exec) {
+  assert(UseLargePages, "only for large pages");
+
+  if (!is_size_aligned(bytes, os::large_page_size()) || alignment > os::large_page_size()) {
+    return NULL; // Fallback to small pages.
+  }
 
   const DWORD prot = exec ? PAGE_EXECUTE_READWRITE : PAGE_READWRITE;
   const DWORD flags = MEM_RESERVE | MEM_COMMIT | MEM_LARGE_PAGES;
@@ -5638,3 +5643,9 @@
 }
 
 #endif
+
+#ifndef PRODUCT
+void TestReserveMemorySpecial_test() {
+  // No tests available for this platform
+}
+#endif