1 /* 2 * Copyright (c) 1997, 2011, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 #ifndef SHARE_VM_RUNTIME_OS_HPP 26 #define SHARE_VM_RUNTIME_OS_HPP 27 28 #include "jvmtifiles/jvmti.h" 29 #include "runtime/atomic.hpp" 30 #include "runtime/extendedPC.hpp" 31 #include "runtime/handles.hpp" 32 #include "utilities/top.hpp" 33 #ifdef TARGET_OS_FAMILY_linux 34 # include "jvm_linux.h" 35 #endif 36 #ifdef TARGET_OS_FAMILY_solaris 37 # include "jvm_solaris.h" 38 #endif 39 #ifdef TARGET_OS_FAMILY_windows 40 # include "jvm_windows.h" 41 #endif 42 #ifdef TARGET_OS_FAMILY_bsd 43 # include "jvm_bsd.h" 44 #endif 45 46 // os defines the interface to operating system; this includes traditional 47 // OS services (time, I/O) as well as other functionality with system- 48 // dependent code. 49 50 typedef void (*dll_func)(...); 51 52 class Thread; 53 class JavaThread; 54 class Event; 55 class DLL; 56 class FileHandle; 57 template<class E> class GrowableArray; 58 59 // %%%%% Moved ThreadState, START_FN, OSThread to new osThread.hpp. -- Rose 60 61 // Platform-independent error return values from OS functions 62 enum OSReturn { 63 OS_OK = 0, // Operation was successful 64 OS_ERR = -1, // Operation failed 65 OS_INTRPT = -2, // Operation was interrupted 66 OS_TIMEOUT = -3, // Operation timed out 67 OS_NOMEM = -5, // Operation failed for lack of memory 68 OS_NORESOURCE = -6 // Operation failed for lack of nonmemory resource 69 }; 70 71 enum ThreadPriority { // JLS 20.20.1-3 72 NoPriority = -1, // Initial non-priority value 73 MinPriority = 1, // Minimum priority 74 NormPriority = 5, // Normal (non-daemon) priority 75 NearMaxPriority = 9, // High priority, used for VMThread 76 MaxPriority = 10, // Highest priority, used for WatcherThread 77 // ensures that VMThread doesn't starve profiler 78 CriticalPriority = 11 // Critical thread priority 79 }; 80 81 // Typedef for structured exception handling support 82 typedef void (*java_call_t)(JavaValue* value, methodHandle* method, JavaCallArguments* args, Thread* thread); 83 84 class os: AllStatic { 85 public: 86 enum { page_sizes_max = 9 }; // Size of _page_sizes array (8 plus a sentinel) 87 88 private: 89 static OSThread* _starting_thread; 90 static address _polling_page; 91 static volatile int32_t * _mem_serialize_page; 92 static uintptr_t _serialize_page_mask; 93 public: 94 static size_t _page_sizes[page_sizes_max]; 95 96 private: 97 static void init_page_sizes(size_t default_page_size) { 98 _page_sizes[0] = default_page_size; 99 _page_sizes[1] = 0; // sentinel 100 } 101 102 public: 103 static void init(void); // Called before command line parsing 104 static jint init_2(void); // Called after command line parsing 105 static void init_globals(void) { // Called from init_globals() in init.cpp 106 init_globals_ext(); 107 } 108 static void init_3(void); // Called at the end of vm init 109 110 // File names are case-insensitive on windows only 111 // Override me as needed 112 static int file_name_strcmp(const char* s1, const char* s2); 113 114 static bool getenv(const char* name, char* buffer, int len); 115 static bool have_special_privileges(); 116 117 static jlong javaTimeMillis(); 118 static jlong javaTimeNanos(); 119 static void javaTimeNanos_info(jvmtiTimerInfo *info_ptr); 120 static void run_periodic_checks(); 121 122 123 // Returns the elapsed time in seconds since the vm started. 124 static double elapsedTime(); 125 126 // Returns real time in seconds since an arbitrary point 127 // in the past. 128 static bool getTimesSecs(double* process_real_time, 129 double* process_user_time, 130 double* process_system_time); 131 132 // Interface to the performance counter 133 static jlong elapsed_counter(); 134 static jlong elapsed_frequency(); 135 136 // The "virtual time" of a thread is the amount of time a thread has 137 // actually run. The first function indicates whether the OS supports 138 // this functionality for the current thread, and if so: 139 // * the second enables vtime tracking (if that is required). 140 // * the third tells whether vtime is enabled. 141 // * the fourth returns the elapsed virtual time for the current 142 // thread. 143 static bool supports_vtime(); 144 static bool enable_vtime(); 145 static bool vtime_enabled(); 146 static double elapsedVTime(); 147 148 // Return current local time in a string (YYYY-MM-DD HH:MM:SS). 149 // It is MT safe, but not async-safe, as reading time zone 150 // information may require a lock on some platforms. 151 static char* local_time_string(char *buf, size_t buflen); 152 static struct tm* localtime_pd (const time_t* clock, struct tm* res); 153 // Fill in buffer with current local time as an ISO-8601 string. 154 // E.g., YYYY-MM-DDThh:mm:ss.mmm+zzzz. 155 // Returns buffer, or NULL if it failed. 156 static char* iso8601_time(char* buffer, size_t buffer_length); 157 158 // Interface for detecting multiprocessor system 159 static inline bool is_MP() { 160 assert(_processor_count > 0, "invalid processor count"); 161 return _processor_count > 1; 162 } 163 static julong available_memory(); 164 static julong physical_memory(); 165 static julong allocatable_physical_memory(julong size); 166 static bool is_server_class_machine(); 167 168 // number of CPUs 169 static int processor_count() { 170 return _processor_count; 171 } 172 static void set_processor_count(int count) { _processor_count = count; } 173 174 // Returns the number of CPUs this process is currently allowed to run on. 175 // Note that on some OSes this can change dynamically. 176 static int active_processor_count(); 177 178 // Bind processes to processors. 179 // This is a two step procedure: 180 // first you generate a distribution of processes to processors, 181 // then you bind processes according to that distribution. 182 // Compute a distribution for number of processes to processors. 183 // Stores the processor id's into the distribution array argument. 184 // Returns true if it worked, false if it didn't. 185 static bool distribute_processes(uint length, uint* distribution); 186 // Binds the current process to a processor. 187 // Returns true if it worked, false if it didn't. 188 static bool bind_to_processor(uint processor_id); 189 190 // Give a name to the current thread. 191 static void set_native_thread_name(const char *name); 192 193 // Interface for stack banging (predetect possible stack overflow for 194 // exception processing) There are guard pages, and above that shadow 195 // pages for stack overflow checking. 196 static bool uses_stack_guard_pages(); 197 static bool allocate_stack_guard_pages(); 198 static void bang_stack_shadow_pages(); 199 static bool stack_shadow_pages_available(Thread *thread, methodHandle method); 200 201 // OS interface to Virtual Memory 202 203 // Return the default page size. 204 static int vm_page_size(); 205 206 // Return the page size to use for a region of memory. The min_pages argument 207 // is a hint intended to limit fragmentation; it says the returned page size 208 // should be <= region_max_size / min_pages. Because min_pages is a hint, 209 // this routine may return a size larger than region_max_size / min_pages. 210 // 211 // The current implementation ignores min_pages if a larger page size is an 212 // exact multiple of both region_min_size and region_max_size. This allows 213 // larger pages to be used when doing so would not cause fragmentation; in 214 // particular, a single page can be used when region_min_size == 215 // region_max_size == a supported page size. 216 static size_t page_size_for_region(size_t region_min_size, 217 size_t region_max_size, 218 uint min_pages); 219 220 // Methods for tracing page sizes returned by the above method; enabled by 221 // TracePageSizes. The region_{min,max}_size parameters should be the values 222 // passed to page_size_for_region() and page_size should be the result of that 223 // call. The (optional) base and size parameters should come from the 224 // ReservedSpace base() and size() methods. 225 static void trace_page_sizes(const char* str, const size_t* page_sizes, 226 int count) PRODUCT_RETURN; 227 static void trace_page_sizes(const char* str, const size_t region_min_size, 228 const size_t region_max_size, 229 const size_t page_size, 230 const char* base = NULL, 231 const size_t size = 0) PRODUCT_RETURN; 232 233 static int vm_allocation_granularity(); 234 static char* reserve_memory(size_t bytes, char* addr = 0, 235 size_t alignment_hint = 0); 236 static char* attempt_reserve_memory_at(size_t bytes, char* addr); 237 static void split_reserved_memory(char *base, size_t size, 238 size_t split, bool realloc); 239 static bool commit_memory(char* addr, size_t bytes, 240 bool executable = false); 241 static bool commit_memory(char* addr, size_t size, size_t alignment_hint, 242 bool executable = false); 243 static bool uncommit_memory(char* addr, size_t bytes); 244 static bool release_memory(char* addr, size_t bytes); 245 246 enum ProtType { MEM_PROT_NONE, MEM_PROT_READ, MEM_PROT_RW, MEM_PROT_RWX }; 247 static bool protect_memory(char* addr, size_t bytes, ProtType prot, 248 bool is_committed = true); 249 250 static bool guard_memory(char* addr, size_t bytes); 251 static bool unguard_memory(char* addr, size_t bytes); 252 static bool create_stack_guard_pages(char* addr, size_t bytes); 253 static bool remove_stack_guard_pages(char* addr, size_t bytes); 254 255 static char* map_memory(int fd, const char* file_name, size_t file_offset, 256 char *addr, size_t bytes, bool read_only = false, 257 bool allow_exec = false); 258 static char* remap_memory(int fd, const char* file_name, size_t file_offset, 259 char *addr, size_t bytes, bool read_only, 260 bool allow_exec); 261 static bool unmap_memory(char *addr, size_t bytes); 262 static void free_memory(char *addr, size_t bytes, size_t alignment_hint); 263 static void realign_memory(char *addr, size_t bytes, size_t alignment_hint); 264 265 // NUMA-specific interface 266 static bool numa_has_static_binding(); 267 static bool numa_has_group_homing(); 268 static void numa_make_local(char *addr, size_t bytes, int lgrp_hint); 269 static void numa_make_global(char *addr, size_t bytes); 270 static size_t numa_get_groups_num(); 271 static size_t numa_get_leaf_groups(int *ids, size_t size); 272 static bool numa_topology_changed(); 273 static int numa_get_group_id(); 274 275 // Page manipulation 276 struct page_info { 277 size_t size; 278 int lgrp_id; 279 }; 280 static bool get_page_info(char *start, page_info* info); 281 static char* scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found); 282 283 static char* non_memory_address_word(); 284 // reserve, commit and pin the entire memory region 285 static char* reserve_memory_special(size_t size, char* addr = NULL, 286 bool executable = false); 287 static bool release_memory_special(char* addr, size_t bytes); 288 static void large_page_init(); 289 static size_t large_page_size(); 290 static bool can_commit_large_page_memory(); 291 static bool can_execute_large_page_memory(); 292 293 // OS interface to polling page 294 static address get_polling_page() { return _polling_page; } 295 static void set_polling_page(address page) { _polling_page = page; } 296 static bool is_poll_address(address addr) { return addr >= _polling_page && addr < (_polling_page + os::vm_page_size()); } 297 static void make_polling_page_unreadable(); 298 static void make_polling_page_readable(); 299 300 // Routines used to serialize the thread state without using membars 301 static void serialize_thread_states(); 302 303 // Since we write to the serialize page from every thread, we 304 // want stores to be on unique cache lines whenever possible 305 // in order to minimize CPU cross talk. We pre-compute the 306 // amount to shift the thread* to make this offset unique to 307 // each thread. 308 static int get_serialize_page_shift_count() { 309 return SerializePageShiftCount; 310 } 311 312 static void set_serialize_page_mask(uintptr_t mask) { 313 _serialize_page_mask = mask; 314 } 315 316 static unsigned int get_serialize_page_mask() { 317 return _serialize_page_mask; 318 } 319 320 static void set_memory_serialize_page(address page); 321 322 static address get_memory_serialize_page() { 323 return (address)_mem_serialize_page; 324 } 325 326 static inline void write_memory_serialize_page(JavaThread *thread) { 327 uintptr_t page_offset = ((uintptr_t)thread >> 328 get_serialize_page_shift_count()) & 329 get_serialize_page_mask(); 330 *(volatile int32_t *)((uintptr_t)_mem_serialize_page+page_offset) = 1; 331 } 332 333 static bool is_memory_serialize_page(JavaThread *thread, address addr) { 334 if (UseMembar) return false; 335 // Previously this function calculated the exact address of this 336 // thread's serialize page, and checked if the faulting address 337 // was equal. However, some platforms mask off faulting addresses 338 // to the page size, so now we just check that the address is 339 // within the page. This makes the thread argument unnecessary, 340 // but we retain the NULL check to preserve existing behaviour. 341 if (thread == NULL) return false; 342 address page = (address) _mem_serialize_page; 343 return addr >= page && addr < (page + os::vm_page_size()); 344 } 345 346 static void block_on_serialize_page_trap(); 347 348 // threads 349 350 enum ThreadType { 351 vm_thread, 352 cgc_thread, // Concurrent GC thread 353 pgc_thread, // Parallel GC thread 354 java_thread, 355 compiler_thread, 356 watcher_thread, 357 os_thread 358 }; 359 360 static bool create_thread(Thread* thread, 361 ThreadType thr_type, 362 size_t stack_size = 0); 363 static bool create_main_thread(JavaThread* thread); 364 static bool create_attached_thread(JavaThread* thread); 365 static void pd_start_thread(Thread* thread); 366 static void start_thread(Thread* thread); 367 368 static void initialize_thread(); 369 static void free_thread(OSThread* osthread); 370 371 // thread id on Linux/64bit is 64bit, on Windows and Solaris, it's 32bit 372 static intx current_thread_id(); 373 static int current_process_id(); 374 static int sleep(Thread* thread, jlong ms, bool interruptable); 375 static int naked_sleep(); 376 static void infinite_sleep(); // never returns, use with CAUTION 377 static void yield(); // Yields to all threads with same priority 378 enum YieldResult { 379 YIELD_SWITCHED = 1, // caller descheduled, other ready threads exist & ran 380 YIELD_NONEREADY = 0, // No other runnable/ready threads. 381 // platform-specific yield return immediately 382 YIELD_UNKNOWN = -1 // Unknown: platform doesn't support _SWITCHED or _NONEREADY 383 // YIELD_SWITCHED and YIELD_NONREADY imply the platform supports a "strong" 384 // yield that can be used in lieu of blocking. 385 } ; 386 static YieldResult NakedYield () ; 387 static void yield_all(int attempts = 0); // Yields to all other threads including lower priority 388 static void loop_breaker(int attempts); // called from within tight loops to possibly influence time-sharing 389 static OSReturn set_priority(Thread* thread, ThreadPriority priority); 390 static OSReturn get_priority(const Thread* const thread, ThreadPriority& priority); 391 392 static void interrupt(Thread* thread); 393 static bool is_interrupted(Thread* thread, bool clear_interrupted); 394 395 static int pd_self_suspend_thread(Thread* thread); 396 397 static ExtendedPC fetch_frame_from_context(void* ucVoid, intptr_t** sp, intptr_t** fp); 398 static frame fetch_frame_from_context(void* ucVoid); 399 400 static ExtendedPC get_thread_pc(Thread *thread); 401 static void breakpoint(); 402 403 static address current_stack_pointer(); 404 static address current_stack_base(); 405 static size_t current_stack_size(); 406 407 static int message_box(const char* title, const char* message); 408 static char* do_you_want_to_debug(const char* message); 409 410 // run cmd in a separate process and return its exit code; or -1 on failures 411 static int fork_and_exec(char *cmd); 412 413 // Set file to send error reports. 414 static void set_error_file(const char *logfile); 415 416 // os::exit() is merged with vm_exit() 417 // static void exit(int num); 418 419 // Terminate the VM, but don't exit the process 420 static void shutdown(); 421 422 // Terminate with an error. Default is to generate a core file on platforms 423 // that support such things. This calls shutdown() and then aborts. 424 static void abort(bool dump_core = true); 425 426 // Die immediately, no exit hook, no abort hook, no cleanup. 427 static void die(); 428 429 // File i/o operations 430 static const int default_file_open_flags(); 431 static int open(const char *path, int oflag, int mode); 432 static int close(int fd); 433 static jlong lseek(int fd, jlong offset, int whence); 434 static char* native_path(char *path); 435 static int ftruncate(int fd, jlong length); 436 static int fsync(int fd); 437 static int available(int fd, jlong *bytes); 438 439 //File i/o operations 440 441 static size_t read(int fd, void *buf, unsigned int nBytes); 442 static size_t restartable_read(int fd, void *buf, unsigned int nBytes); 443 static size_t write(int fd, const void *buf, unsigned int nBytes); 444 445 // Reading directories. 446 static DIR* opendir(const char* dirname); 447 static int readdir_buf_size(const char *path); 448 static struct dirent* readdir(DIR* dirp, dirent* dbuf); 449 static int closedir(DIR* dirp); 450 451 // Dynamic library extension 452 static const char* dll_file_extension(); 453 454 static const char* get_temp_directory(); 455 static const char* get_current_directory(char *buf, int buflen); 456 457 // Builds a platform-specific full library path given a ld path and lib name 458 static void dll_build_name(char* buffer, size_t size, 459 const char* pathname, const char* fname); 460 461 // Symbol lookup, find nearest function name; basically it implements 462 // dladdr() for all platforms. Name of the nearest function is copied 463 // to buf. Distance from its base address is returned as offset. 464 // If function name is not found, buf[0] is set to '\0' and offset is 465 // set to -1. 466 static bool dll_address_to_function_name(address addr, char* buf, 467 int buflen, int* offset); 468 469 // Locate DLL/DSO. On success, full path of the library is copied to 470 // buf, and offset is set to be the distance between addr and the 471 // library's base address. On failure, buf[0] is set to '\0' and 472 // offset is set to -1. 473 static bool dll_address_to_library_name(address addr, char* buf, 474 int buflen, int* offset); 475 476 // Find out whether the pc is in the static code for jvm.dll/libjvm.so. 477 static bool address_is_in_vm(address addr); 478 479 // Loads .dll/.so and 480 // in case of error it checks if .dll/.so was built for the 481 // same architecture as Hotspot is running on 482 static void* dll_load(const char *name, char *ebuf, int ebuflen); 483 484 // lookup symbol in a shared library 485 static void* dll_lookup(void* handle, const char* name); 486 487 // Unload library 488 static void dll_unload(void *lib); 489 490 // Print out system information; they are called by fatal error handler. 491 // Output format may be different on different platforms. 492 static void print_os_info(outputStream* st); 493 static void print_cpu_info(outputStream* st); 494 static void pd_print_cpu_info(outputStream* st); 495 static void print_memory_info(outputStream* st); 496 static void print_dll_info(outputStream* st); 497 static void print_environment_variables(outputStream* st, const char** env_list, char* buffer, int len); 498 static void print_context(outputStream* st, void* context); 499 static void print_register_info(outputStream* st, void* context); 500 static void print_siginfo(outputStream* st, void* siginfo); 501 static void print_signal_handlers(outputStream* st, char* buf, size_t buflen); 502 static void print_date_and_time(outputStream* st); 503 504 static void print_location(outputStream* st, intptr_t x, bool verbose = false); 505 static size_t lasterror(char *buf, size_t len); 506 static int get_last_error(); 507 508 // Determines whether the calling process is being debugged by a user-mode debugger. 509 static bool is_debugger_attached(); 510 511 // wait for a key press if PauseAtExit is set 512 static void wait_for_keypress_at_exit(void); 513 514 // The following two functions are used by fatal error handler to trace 515 // native (C) frames. They are not part of frame.hpp/frame.cpp because 516 // frame.hpp/cpp assume thread is JavaThread, and also because different 517 // OS/compiler may have different convention or provide different API to 518 // walk C frames. 519 // 520 // We don't attempt to become a debugger, so we only follow frames if that 521 // does not require a lookup in the unwind table, which is part of the binary 522 // file but may be unsafe to read after a fatal error. So on x86, we can 523 // only walk stack if %ebp is used as frame pointer; on ia64, it's not 524 // possible to walk C stack without having the unwind table. 525 static bool is_first_C_frame(frame *fr); 526 static frame get_sender_for_C_frame(frame *fr); 527 528 // return current frame. pc() and sp() are set to NULL on failure. 529 static frame current_frame(); 530 531 static void print_hex_dump(outputStream* st, address start, address end, int unitsize); 532 533 // returns a string to describe the exception/signal; 534 // returns NULL if exception_code is not an OS exception/signal. 535 static const char* exception_name(int exception_code, char* buf, size_t buflen); 536 537 // Returns native Java library, loads if necessary 538 static void* native_java_library(); 539 540 // Fills in path to jvm.dll/libjvm.so (used by the Disassembler) 541 static void jvm_path(char *buf, jint buflen); 542 543 // Returns true if we are running in a headless jre. 544 static bool is_headless_jre(); 545 546 // JNI names 547 static void print_jni_name_prefix_on(outputStream* st, int args_size); 548 static void print_jni_name_suffix_on(outputStream* st, int args_size); 549 550 // File conventions 551 static const char* file_separator(); 552 static const char* line_separator(); 553 static const char* path_separator(); 554 555 // Init os specific system properties values 556 static void init_system_properties_values(); 557 558 // IO operations, non-JVM_ version. 559 static int stat(const char* path, struct stat* sbuf); 560 static bool dir_is_empty(const char* path); 561 562 // IO operations on binary files 563 static int create_binary_file(const char* path, bool rewrite_existing); 564 static jlong current_file_offset(int fd); 565 static jlong seek_to_file_offset(int fd, jlong offset); 566 567 // Thread Local Storage 568 static int allocate_thread_local_storage(); 569 static void thread_local_storage_at_put(int index, void* value); 570 static void* thread_local_storage_at(int index); 571 static void free_thread_local_storage(int index); 572 573 // General allocation (must be MT-safe) 574 static void* malloc (size_t size); 575 static void* realloc (void *memblock, size_t size); 576 static void free (void *memblock); 577 static bool check_heap(bool force = false); // verify C heap integrity 578 static char* strdup(const char *); // Like strdup 579 580 #ifndef PRODUCT 581 static julong num_mallocs; // # of calls to malloc/realloc 582 static julong alloc_bytes; // # of bytes allocated 583 static julong num_frees; // # of calls to free 584 static julong free_bytes; // # of bytes freed 585 #endif 586 587 // SocketInterface (ex HPI SocketInterface ) 588 static int socket(int domain, int type, int protocol); 589 static int socket_close(int fd); 590 static int socket_shutdown(int fd, int howto); 591 static int recv(int fd, char* buf, size_t nBytes, uint flags); 592 static int send(int fd, char* buf, size_t nBytes, uint flags); 593 static int raw_send(int fd, char* buf, size_t nBytes, uint flags); 594 static int timeout(int fd, long timeout); 595 static int listen(int fd, int count); 596 static int connect(int fd, struct sockaddr* him, socklen_t len); 597 static int bind(int fd, struct sockaddr* him, socklen_t len); 598 static int accept(int fd, struct sockaddr* him, socklen_t* len); 599 static int recvfrom(int fd, char* buf, size_t nbytes, uint flags, 600 struct sockaddr* from, socklen_t* fromlen); 601 static int get_sock_name(int fd, struct sockaddr* him, socklen_t* len); 602 static int sendto(int fd, char* buf, size_t len, uint flags, 603 struct sockaddr* to, socklen_t tolen); 604 static int socket_available(int fd, jint* pbytes); 605 606 static int get_sock_opt(int fd, int level, int optname, 607 char* optval, socklen_t* optlen); 608 static int set_sock_opt(int fd, int level, int optname, 609 const char* optval, socklen_t optlen); 610 static int get_host_name(char* name, int namelen); 611 612 static struct hostent* get_host_by_name(char* name); 613 614 // Printing 64 bit integers 615 static const char* jlong_format_specifier(); 616 static const char* julong_format_specifier(); 617 618 // Support for signals (see JVM_RaiseSignal, JVM_RegisterSignal) 619 static void signal_init(); 620 static void signal_init_pd(); 621 static void signal_notify(int signal_number); 622 static void* signal(int signal_number, void* handler); 623 static void signal_raise(int signal_number); 624 static int signal_wait(); 625 static int signal_lookup(); 626 static void* user_handler(); 627 static void terminate_signal_thread(); 628 static int sigexitnum_pd(); 629 630 // random number generation 631 static long random(); // return 32bit pseudorandom number 632 static void init_random(long initval); // initialize random sequence 633 634 // Structured OS Exception support 635 static void os_exception_wrapper(java_call_t f, JavaValue* value, methodHandle* method, JavaCallArguments* args, Thread* thread); 636 637 // On Windows this will create an actual minidump, on Linux/Solaris it will simply check core dump limits 638 static void check_or_create_dump(void* exceptionRecord, void* contextRecord, char* buffer, size_t bufferSize); 639 640 // JVMTI & JVM monitoring and management support 641 // The thread_cpu_time() and current_thread_cpu_time() are only 642 // supported if is_thread_cpu_time_supported() returns true. 643 // They are not supported on Solaris T1. 644 645 // Thread CPU Time - return the fast estimate on a platform 646 // On Solaris - call gethrvtime (fast) - user time only 647 // On Linux - fast clock_gettime where available - user+sys 648 // - otherwise: very slow /proc fs - user+sys 649 // On Windows - GetThreadTimes - user+sys 650 static jlong current_thread_cpu_time(); 651 static jlong thread_cpu_time(Thread* t); 652 653 // Thread CPU Time with user_sys_cpu_time parameter. 654 // 655 // If user_sys_cpu_time is true, user+sys time is returned. 656 // Otherwise, only user time is returned 657 static jlong current_thread_cpu_time(bool user_sys_cpu_time); 658 static jlong thread_cpu_time(Thread* t, bool user_sys_cpu_time); 659 660 // Return a bunch of info about the timers. 661 // Note that the returned info for these two functions may be different 662 // on some platforms 663 static void current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr); 664 static void thread_cpu_time_info(jvmtiTimerInfo *info_ptr); 665 666 static bool is_thread_cpu_time_supported(); 667 668 // System loadavg support. Returns -1 if load average cannot be obtained. 669 static int loadavg(double loadavg[], int nelem); 670 671 // Hook for os specific jvm options that we don't want to abort on seeing 672 static bool obsolete_option(const JavaVMOption *option); 673 674 // Read file line by line. If line is longer than bsize, 675 // rest of line is skipped. Returns number of bytes read or -1 on EOF 676 static int get_line_chars(int fd, char *buf, const size_t bsize); 677 678 // Extensions 679 #include "runtime/os_ext.hpp" 680 681 public: 682 683 // Platform dependent stuff 684 #ifdef TARGET_OS_FAMILY_linux 685 # include "os_linux.hpp" 686 #endif 687 #ifdef TARGET_OS_FAMILY_solaris 688 # include "os_solaris.hpp" 689 #endif 690 #ifdef TARGET_OS_FAMILY_windows 691 # include "os_windows.hpp" 692 #endif 693 #ifdef TARGET_OS_FAMILY_bsd 694 # include "os_bsd.hpp" 695 #endif 696 #ifdef TARGET_OS_ARCH_linux_x86 697 # include "os_linux_x86.hpp" 698 #endif 699 #ifdef TARGET_OS_ARCH_linux_sparc 700 # include "os_linux_sparc.hpp" 701 #endif 702 #ifdef TARGET_OS_ARCH_linux_zero 703 # include "os_linux_zero.hpp" 704 #endif 705 #ifdef TARGET_OS_ARCH_solaris_x86 706 # include "os_solaris_x86.hpp" 707 #endif 708 #ifdef TARGET_OS_ARCH_solaris_sparc 709 # include "os_solaris_sparc.hpp" 710 #endif 711 #ifdef TARGET_OS_ARCH_windows_x86 712 # include "os_windows_x86.hpp" 713 #endif 714 #ifdef TARGET_OS_ARCH_linux_arm 715 # include "os_linux_arm.hpp" 716 #endif 717 #ifdef TARGET_OS_ARCH_linux_ppc 718 # include "os_linux_ppc.hpp" 719 #endif 720 #ifdef TARGET_OS_ARCH_bsd_x86 721 # include "os_bsd_x86.hpp" 722 #endif 723 #ifdef TARGET_OS_ARCH_bsd_zero 724 # include "os_bsd_zero.hpp" 725 #endif 726 727 public: 728 // debugging support (mostly used by debug.cpp but also fatal error handler) 729 static bool find(address pc, outputStream* st = tty); // OS specific function to make sense out of an address 730 731 static bool dont_yield(); // when true, JVM_Yield() is nop 732 static void print_statistics(); 733 734 // Thread priority helpers (implemented in OS-specific part) 735 static OSReturn set_native_priority(Thread* thread, int native_prio); 736 static OSReturn get_native_priority(const Thread* const thread, int* priority_ptr); 737 static int java_to_os_priority[CriticalPriority + 1]; 738 // Hint to the underlying OS that a task switch would not be good. 739 // Void return because it's a hint and can fail. 740 static void hint_no_preempt(); 741 742 // Used at creation if requested by the diagnostic flag PauseAtStartup. 743 // Causes the VM to wait until an external stimulus has been applied 744 // (for Unix, that stimulus is a signal, for Windows, an external 745 // ResumeThread call) 746 static void pause(); 747 748 protected: 749 static long _rand_seed; // seed for random number generator 750 static int _processor_count; // number of processors 751 752 static char* format_boot_path(const char* format_string, 753 const char* home, 754 int home_len, 755 char fileSep, 756 char pathSep); 757 static bool set_boot_path(char fileSep, char pathSep); 758 static char** split_path(const char* path, int* n); 759 }; 760 761 // Note that "PAUSE" is almost always used with synchronization 762 // so arguably we should provide Atomic::SpinPause() instead 763 // of the global SpinPause() with C linkage. 764 // It'd also be eligible for inlining on many platforms. 765 766 extern "C" int SpinPause () ; 767 extern "C" int SafeFetch32 (int * adr, int errValue) ; 768 extern "C" intptr_t SafeFetchN (intptr_t * adr, intptr_t errValue) ; 769 770 #endif // SHARE_VM_RUNTIME_OS_HPP