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src/hotspot/os/windows/os_windows.cpp
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@@ -2880,10 +2880,74 @@
cleanup_after_large_page_init();
UseLargePages = success;
}
+int os::create_file_for_heap(const char* dir) {
+
+ const char name_template[] = "/jvmheap.XXXXXX";
+ char *fullname = (char*)os::malloc((strlen(dir) + strlen(name_template) + 1), mtInternal);
+ if (fullname == NULL) {
+ vm_exit_during_initialization(err_msg("Malloc failed during creation of backing file for heap (%s)", os::strerror(errno)));
+ return -1;
+ }
+
+ (void)strncpy(fullname, dir, strlen(dir)+1);
+ (void)strncat(fullname, name_template, strlen(name_template));
+
+ os::native_path(fullname);
+
+ char *path = _mktemp(fullname);
+ if (path == NULL) {
+ warning("_mktemp could not create file name from template %s (%s)", fullname, os::strerror(errno));
+ os::free(fullname);
+ return -1;
+ }
+
+ int fd = _open(path, O_RDWR | O_CREAT | O_TEMPORARY | O_EXCL, S_IWRITE | S_IREAD);
+
+ os::free(fullname);
+ if (fd < 0) {
+ warning("Problem opening file for heap (%s)", os::strerror(errno));
+ return -1;
+ }
+ return fd;
+}
+
+// If 'base' is not NULL, function will return NULL if it cannot get 'base'
+char* os::map_memory_to_file(char* base, size_t size, int fd) {
+ assert(fd != -1, "File descriptor is not valid");
+
+ HANDLE fh = (HANDLE)_get_osfhandle(fd);
+ HANDLE fileMapping = CreateFileMapping(fh, NULL, PAGE_READWRITE,
+ (DWORD)(size >> 32), (DWORD)(size & 0xFFFFFFFF), NULL);
+ if (fileMapping == NULL) {
+ if (GetLastError() == ERROR_DISK_FULL) {
+ vm_exit_during_initialization(err_msg("Could not allocate sufficient disk space for Java heap"));
+ }
+ else {
+ vm_exit_during_initialization(err_msg("Error in mapping Java heap at the given filesystem directory"));
+ }
+
+ return NULL;
+ }
+
+ LPVOID addr = MapViewOfFileEx(fileMapping, FILE_MAP_WRITE, 0, 0, size, base);
+
+ CloseHandle(fileMapping);
+
+ return (char*)addr;
+}
+
+char* os::replace_existing_mapping_with_file_mapping(char* base, size_t size, int fd) {
+ assert(fd != -1, "File descriptor is not valid");
+ assert(base != NULL, "Base address cannot be NULL");
+
+ release_memory(base, size);
+ return map_memory_to_file(base, size, fd);
+}
+
// On win32, one cannot release just a part of reserved memory, it's an
// all or nothing deal. When we split a reservation, we must break the
// reservation into two reservations.
void os::pd_split_reserved_memory(char *base, size_t size, size_t split,
bool realloc) {
@@ -2899,31 +2963,35 @@
}
// Multiple threads can race in this code but it's not possible to unmap small sections of
// virtual space to get requested alignment, like posix-like os's.
// Windows prevents multiple thread from remapping over each other so this loop is thread-safe.
-char* os::reserve_memory_aligned(size_t size, size_t alignment) {
+char* os::reserve_memory_aligned(size_t size, size_t alignment, int file_desc) {
assert((alignment & (os::vm_allocation_granularity() - 1)) == 0,
"Alignment must be a multiple of allocation granularity (page size)");
assert((size & (alignment -1)) == 0, "size must be 'alignment' aligned");
size_t extra_size = size + alignment;
assert(extra_size >= size, "overflow, size is too large to allow alignment");
char* aligned_base = NULL;
do {
- char* extra_base = os::reserve_memory(extra_size, NULL, alignment);
+ char* extra_base = os::reserve_memory(extra_size, NULL, alignment, file_desc);
if (extra_base == NULL) {
return NULL;
}
// Do manual alignment
aligned_base = align_up(extra_base, alignment);
+ if (file_desc != -1) {
+ os::unmap_memory(extra_base, extra_size);
+ } else {
os::release_memory(extra_base, extra_size);
+ }
- aligned_base = os::reserve_memory(size, aligned_base);
+ aligned_base = os::reserve_memory(size, aligned_base, 0, file_desc);
} while (aligned_base == NULL);
return aligned_base;
}
@@ -2965,10 +3033,15 @@
// Windows os::reserve_memory() fails of the requested address range is
// not avilable.
return reserve_memory(bytes, requested_addr);
}
+char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr, int file_desc) {
+ assert(file_desc >= 0, "file_desc is not valid");
+ return map_memory_to_file(requested_addr, bytes, file_desc);
+}
+
size_t os::large_page_size() {
return _large_page_size;
}
bool os::can_commit_large_page_memory() {
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