1.1 --- a/src/os/windows/vm/os_windows.cpp Wed Oct 01 15:05:06 2008 -0400
1.2 +++ b/src/os/windows/vm/os_windows.cpp Thu Oct 02 12:01:08 2008 -0700
1.3 @@ -2593,9 +2593,104 @@
1.4 }
1.5
1.6 char* os::reserve_memory_special(size_t bytes) {
1.7 - DWORD flag = MEM_RESERVE | MEM_COMMIT | MEM_LARGE_PAGES;
1.8 - char * res = (char *)VirtualAlloc(NULL, bytes, flag, PAGE_EXECUTE_READWRITE);
1.9 - return res;
1.10 +
1.11 + if (UseLargePagesIndividualAllocation) {
1.12 + if (TracePageSizes && Verbose) {
1.13 + tty->print_cr("Reserving large pages individually.");
1.14 + }
1.15 + char * p_buf;
1.16 + // first reserve enough address space in advance since we want to be
1.17 + // able to break a single contiguous virtual address range into multiple
1.18 + // large page commits but WS2003 does not allow reserving large page space
1.19 + // so we just use 4K pages for reserve, this gives us a legal contiguous
1.20 + // address space. then we will deallocate that reservation, and re alloc
1.21 + // using large pages
1.22 + const size_t size_of_reserve = bytes + _large_page_size;
1.23 + if (bytes > size_of_reserve) {
1.24 + // Overflowed.
1.25 + warning("Individually allocated large pages failed, "
1.26 + "use -XX:-UseLargePagesIndividualAllocation to turn off");
1.27 + return NULL;
1.28 + }
1.29 + p_buf = (char *) VirtualAlloc(NULL,
1.30 + size_of_reserve, // size of Reserve
1.31 + MEM_RESERVE,
1.32 + PAGE_EXECUTE_READWRITE);
1.33 + // If reservation failed, return NULL
1.34 + if (p_buf == NULL) return NULL;
1.35 +
1.36 + release_memory(p_buf, bytes + _large_page_size);
1.37 + // round up to page boundary. If the size_of_reserve did not
1.38 + // overflow and the reservation did not fail, this align up
1.39 + // should not overflow.
1.40 + p_buf = (char *) align_size_up((size_t)p_buf, _large_page_size);
1.41 +
1.42 + // now go through and allocate one page at a time until all bytes are
1.43 + // allocated
1.44 + size_t bytes_remaining = align_size_up(bytes, _large_page_size);
1.45 + // An overflow of align_size_up() would have been caught above
1.46 + // in the calculation of size_of_reserve.
1.47 + char * next_alloc_addr = p_buf;
1.48 +
1.49 +#ifdef ASSERT
1.50 + // Variable for the failure injection
1.51 + long ran_num = os::random();
1.52 + size_t fail_after = ran_num % bytes;
1.53 +#endif
1.54 +
1.55 + while (bytes_remaining) {
1.56 + size_t bytes_to_rq = MIN2(bytes_remaining, _large_page_size);
1.57 + // Note allocate and commit
1.58 + char * p_new;
1.59 +
1.60 +#ifdef ASSERT
1.61 + bool inject_error = LargePagesIndividualAllocationInjectError &&
1.62 + (bytes_remaining <= fail_after);
1.63 +#else
1.64 + const bool inject_error = false;
1.65 +#endif
1.66 +
1.67 + if (inject_error) {
1.68 + p_new = NULL;
1.69 + } else {
1.70 + p_new = (char *) VirtualAlloc(next_alloc_addr,
1.71 + bytes_to_rq,
1.72 + MEM_RESERVE | MEM_COMMIT | MEM_LARGE_PAGES,
1.73 + PAGE_EXECUTE_READWRITE);
1.74 + }
1.75 +
1.76 + if (p_new == NULL) {
1.77 + // Free any allocated pages
1.78 + if (next_alloc_addr > p_buf) {
1.79 + // Some memory was committed so release it.
1.80 + size_t bytes_to_release = bytes - bytes_remaining;
1.81 + release_memory(p_buf, bytes_to_release);
1.82 + }
1.83 +#ifdef ASSERT
1.84 + if (UseLargePagesIndividualAllocation &&
1.85 + LargePagesIndividualAllocationInjectError) {
1.86 + if (TracePageSizes && Verbose) {
1.87 + tty->print_cr("Reserving large pages individually failed.");
1.88 + }
1.89 + }
1.90 +#endif
1.91 + return NULL;
1.92 + }
1.93 + bytes_remaining -= bytes_to_rq;
1.94 + next_alloc_addr += bytes_to_rq;
1.95 + }
1.96 +
1.97 + return p_buf;
1.98 +
1.99 + } else {
1.100 + // normal policy just allocate it all at once
1.101 + DWORD flag = MEM_RESERVE | MEM_COMMIT | MEM_LARGE_PAGES;
1.102 + char * res = (char *)VirtualAlloc(NULL,
1.103 + bytes,
1.104 + flag,
1.105 + PAGE_EXECUTE_READWRITE);
1.106 + return res;
1.107 + }
1.108 }
1.109
1.110 bool os::release_memory_special(char* base, size_t bytes) {
1.111 @@ -2983,6 +3078,7 @@
1.112 volatile intx os::win32::_os_thread_count = 0;
1.113
1.114 bool os::win32::_is_nt = false;
1.115 +bool os::win32::_is_windows_2003 = false;
1.116
1.117
1.118 void os::win32::initialize_system_info() {
1.119 @@ -3005,7 +3101,15 @@
1.120 GetVersionEx(&oi);
1.121 switch(oi.dwPlatformId) {
1.122 case VER_PLATFORM_WIN32_WINDOWS: _is_nt = false; break;
1.123 - case VER_PLATFORM_WIN32_NT: _is_nt = true; break;
1.124 + case VER_PLATFORM_WIN32_NT:
1.125 + _is_nt = true;
1.126 + {
1.127 + int os_vers = oi.dwMajorVersion * 1000 + oi.dwMinorVersion;
1.128 + if (os_vers == 5002) {
1.129 + _is_windows_2003 = true;
1.130 + }
1.131 + }
1.132 + break;
1.133 default: fatal("Unknown platform");
1.134 }
1.135
1.136 @@ -3103,9 +3207,13 @@
1.137 NoYieldsInMicrolock = true;
1.138 }
1.139 #endif
1.140 + // This may be overridden later when argument processing is done.
1.141 + FLAG_SET_ERGO(bool, UseLargePagesIndividualAllocation,
1.142 + os::win32::is_windows_2003());
1.143 +
1.144 // Initialize main_process and main_thread
1.145 main_process = GetCurrentProcess(); // Remember main_process is a pseudo handle
1.146 - if (!DuplicateHandle(main_process, GetCurrentThread(), main_process,
1.147 + if (!DuplicateHandle(main_process, GetCurrentThread(), main_process,
1.148 &main_thread, THREAD_ALL_ACCESS, false, 0)) {
1.149 fatal("DuplicateHandle failed\n");
1.150 }
