--- a/hotspot/src/os/windows/vm/os_windows.cpp Wed Oct 01 15:05:06 2008 -0400
+++ b/hotspot/src/os/windows/vm/os_windows.cpp Thu Oct 02 12:01:08 2008 -0700
@@ -2593,9 +2593,104 @@
}
char* os::reserve_memory_special(size_t bytes) {
- DWORD flag = MEM_RESERVE | MEM_COMMIT | MEM_LARGE_PAGES;
- char * res = (char *)VirtualAlloc(NULL, bytes, flag, PAGE_EXECUTE_READWRITE);
- return res;
+
+ if (UseLargePagesIndividualAllocation) {
+ if (TracePageSizes && Verbose) {
+ tty->print_cr("Reserving large pages individually.");
+ }
+ char * p_buf;
+ // first reserve enough address space in advance since we want to be
+ // able to break a single contiguous virtual address range into multiple
+ // large page commits but WS2003 does not allow reserving large page space
+ // so we just use 4K pages for reserve, this gives us a legal contiguous
+ // address space. then we will deallocate that reservation, and re alloc
+ // using large pages
+ const size_t size_of_reserve = bytes + _large_page_size;
+ if (bytes > size_of_reserve) {
+ // Overflowed.
+ warning("Individually allocated large pages failed, "
+ "use -XX:-UseLargePagesIndividualAllocation to turn off");
+ return NULL;
+ }
+ p_buf = (char *) VirtualAlloc(NULL,
+ size_of_reserve, // size of Reserve
+ MEM_RESERVE,
+ PAGE_EXECUTE_READWRITE);
+ // If reservation failed, return NULL
+ if (p_buf == NULL) return NULL;
+
+ release_memory(p_buf, bytes + _large_page_size);
+ // round up to page boundary. If the size_of_reserve did not
+ // overflow and the reservation did not fail, this align up
+ // should not overflow.
+ p_buf = (char *) align_size_up((size_t)p_buf, _large_page_size);
+
+ // now go through and allocate one page at a time until all bytes are
+ // allocated
+ size_t bytes_remaining = align_size_up(bytes, _large_page_size);
+ // An overflow of align_size_up() would have been caught above
+ // in the calculation of size_of_reserve.
+ char * next_alloc_addr = p_buf;
+
+#ifdef ASSERT
+ // Variable for the failure injection
+ long ran_num = os::random();
+ size_t fail_after = ran_num % bytes;
+#endif
+
+ while (bytes_remaining) {
+ size_t bytes_to_rq = MIN2(bytes_remaining, _large_page_size);
+ // Note allocate and commit
+ char * p_new;
+
+#ifdef ASSERT
+ bool inject_error = LargePagesIndividualAllocationInjectError &&
+ (bytes_remaining <= fail_after);
+#else
+ const bool inject_error = false;
+#endif
+
+ if (inject_error) {
+ p_new = NULL;
+ } else {
+ p_new = (char *) VirtualAlloc(next_alloc_addr,
+ bytes_to_rq,
+ MEM_RESERVE | MEM_COMMIT | MEM_LARGE_PAGES,
+ PAGE_EXECUTE_READWRITE);
+ }
+
+ if (p_new == NULL) {
+ // Free any allocated pages
+ if (next_alloc_addr > p_buf) {
+ // Some memory was committed so release it.
+ size_t bytes_to_release = bytes - bytes_remaining;
+ release_memory(p_buf, bytes_to_release);
+ }
+#ifdef ASSERT
+ if (UseLargePagesIndividualAllocation &&
+ LargePagesIndividualAllocationInjectError) {
+ if (TracePageSizes && Verbose) {
+ tty->print_cr("Reserving large pages individually failed.");
+ }
+ }
+#endif
+ return NULL;
+ }
+ bytes_remaining -= bytes_to_rq;
+ next_alloc_addr += bytes_to_rq;
+ }
+
+ return p_buf;
+
+ } else {
+ // normal policy just allocate it all at once
+ DWORD flag = MEM_RESERVE | MEM_COMMIT | MEM_LARGE_PAGES;
+ char * res = (char *)VirtualAlloc(NULL,
+ bytes,
+ flag,
+ PAGE_EXECUTE_READWRITE);
+ return res;
+ }
}
bool os::release_memory_special(char* base, size_t bytes) {
@@ -2983,6 +3078,7 @@
volatile intx os::win32::_os_thread_count = 0;
bool os::win32::_is_nt = false;
+bool os::win32::_is_windows_2003 = false;
void os::win32::initialize_system_info() {
@@ -3005,7 +3101,15 @@
GetVersionEx(&oi);
switch(oi.dwPlatformId) {
case VER_PLATFORM_WIN32_WINDOWS: _is_nt = false; break;
- case VER_PLATFORM_WIN32_NT: _is_nt = true; break;
+ case VER_PLATFORM_WIN32_NT:
+ _is_nt = true;
+ {
+ int os_vers = oi.dwMajorVersion * 1000 + oi.dwMinorVersion;
+ if (os_vers == 5002) {
+ _is_windows_2003 = true;
+ }
+ }
+ break;
default: fatal("Unknown platform");
}
@@ -3103,9 +3207,13 @@
NoYieldsInMicrolock = true;
}
#endif
+ // This may be overridden later when argument processing is done.
+ FLAG_SET_ERGO(bool, UseLargePagesIndividualAllocation,
+ os::win32::is_windows_2003());
+
// Initialize main_process and main_thread
main_process = GetCurrentProcess(); // Remember main_process is a pseudo handle
- if (!DuplicateHandle(main_process, GetCurrentThread(), main_process,
+ if (!DuplicateHandle(main_process, GetCurrentThread(), main_process,
&main_thread, THREAD_ALL_ACCESS, false, 0)) {
fatal("DuplicateHandle failed\n");
}