os.hpp revision 0:a61af66fc99e
1/* 2 * Copyright 1997-2007 Sun Microsystems, Inc. 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, 20 * CA 95054 USA or visit www.sun.com if you need additional information or 21 * have any questions. 22 * 23 */ 24 25// os defines the interface to operating system; this includes traditional 26// OS services (time, I/O) as well as other functionality with system- 27// dependent code. 28 29typedef void (*dll_func)(...); 30 31class Thread; 32class JavaThread; 33class Event; 34class DLL; 35class FileHandle; 36 37// %%%%% Moved ThreadState, START_FN, OSThread to new osThread.hpp. -- Rose 38 39// Platform-independent error return values from OS functions 40enum OSReturn { 41 OS_OK = 0, // Operation was successful 42 OS_ERR = -1, // Operation failed 43 OS_INTRPT = -2, // Operation was interrupted 44 OS_TIMEOUT = -3, // Operation timed out 45 OS_NOMEM = -5, // Operation failed for lack of memory 46 OS_NORESOURCE = -6 // Operation failed for lack of nonmemory resource 47}; 48 49enum ThreadPriority { // JLS 20.20.1-3 50 NoPriority = -1, // Initial non-priority value 51 MinPriority = 1, // Minimum priority 52 NormPriority = 5, // Normal (non-daemon) priority 53 NearMaxPriority = 9, // High priority, used for VMThread 54 MaxPriority = 10 // Highest priority, used for WatcherThread 55 // ensures that VMThread doesn't starve profiler 56}; 57 58// Typedef for structured exception handling support 59typedef void (*java_call_t)(JavaValue* value, methodHandle* method, JavaCallArguments* args, Thread* thread); 60 61class os: AllStatic { 62 private: 63 enum { page_sizes_max = 9 }; // Size of _page_sizes array (8 plus a sentinel) 64 65 static OSThread* _starting_thread; 66 static address _polling_page; 67 static volatile int32_t * _mem_serialize_page; 68 static uintptr_t _serialize_page_mask; 69 static volatile jlong _global_time; 70 static volatile int _global_time_lock; 71 static bool _use_global_time; 72 static size_t _page_sizes[page_sizes_max]; 73 74 static void init_page_sizes(size_t default_page_size) { 75 _page_sizes[0] = default_page_size; 76 _page_sizes[1] = 0; // sentinel 77 } 78 79 public: 80 81 static void init(void); // Called before command line parsing 82 static jint init_2(void); // Called after command line parsing 83 84 // File names are case-insensitive on windows only 85 // Override me as needed 86 static int file_name_strcmp(const char* s1, const char* s2); 87 88 static bool getenv(const char* name, char* buffer, int len); 89 static bool have_special_privileges(); 90 91 static jlong timeofday(); 92 static void enable_global_time() { _use_global_time = true; } 93 static void disable_global_time() { _use_global_time = false; } 94 static jlong read_global_time(); 95 static void update_global_time(); 96 static jlong javaTimeMillis(); 97 static jlong javaTimeNanos(); 98 static void javaTimeNanos_info(jvmtiTimerInfo *info_ptr); 99 static void run_periodic_checks(); 100 101 102 // Returns the elapsed time in seconds since the vm started. 103 static double elapsedTime(); 104 105 // Returns real time in seconds since an arbitrary point 106 // in the past. 107 static bool getTimesSecs(double* process_real_time, 108 double* process_user_time, 109 double* process_system_time); 110 111 // Interface to the performance counter 112 static jlong elapsed_counter(); 113 static jlong elapsed_frequency(); 114 115 // Return current local time in a string (YYYY-MM-DD HH:MM:SS). 116 // It is MT safe, but not async-safe, as reading time zone 117 // information may require a lock on some platforms. 118 static char* local_time_string(char *buf, size_t buflen); 119 // Fill in buffer with current local time as an ISO-8601 string. 120 // E.g., YYYY-MM-DDThh:mm:ss.mmm+zzzz. 121 // Returns buffer, or NULL if it failed. 122 static char* iso8601_time(char* buffer, size_t buffer_length); 123 124 // Interface for detecting multiprocessor system 125 static inline bool is_MP() { 126 assert(_processor_count > 0, "invalid processor count"); 127 return _processor_count > 1; 128 } 129 static julong available_memory(); 130 static julong physical_memory(); 131 static julong allocatable_physical_memory(julong size); 132 static bool is_server_class_machine(); 133 134 // number of CPUs 135 static int processor_count() { 136 return _processor_count; 137 } 138 139 // Returns the number of CPUs this process is currently allowed to run on. 140 // Note that on some OSes this can change dynamically. 141 static int active_processor_count(); 142 143 // Bind processes to processors. 144 // This is a two step procedure: 145 // first you generate a distribution of processes to processors, 146 // then you bind processes according to that distribution. 147 // Compute a distribution for number of processes to processors. 148 // Stores the processor id's into the distribution array argument. 149 // Returns true if it worked, false if it didn't. 150 static bool distribute_processes(uint length, uint* distribution); 151 // Binds the current process to a processor. 152 // Returns true if it worked, false if it didn't. 153 static bool bind_to_processor(uint processor_id); 154 155 // Interface for stack banging (predetect possible stack overflow for 156 // exception processing) There are guard pages, and above that shadow 157 // pages for stack overflow checking. 158 static bool uses_stack_guard_pages(); 159 static bool allocate_stack_guard_pages(); 160 static void bang_stack_shadow_pages(); 161 static bool stack_shadow_pages_available(Thread *thread, methodHandle method); 162 163 // OS interface to Virtual Memory 164 165 // Return the default page size. 166 static int vm_page_size(); 167 168 // Return the page size to use for a region of memory. The min_pages argument 169 // is a hint intended to limit fragmentation; it says the returned page size 170 // should be <= region_max_size / min_pages. Because min_pages is a hint, 171 // this routine may return a size larger than region_max_size / min_pages. 172 // 173 // The current implementation ignores min_pages if a larger page size is an 174 // exact multiple of both region_min_size and region_max_size. This allows 175 // larger pages to be used when doing so would not cause fragmentation; in 176 // particular, a single page can be used when region_min_size == 177 // region_max_size == a supported page size. 178 static size_t page_size_for_region(size_t region_min_size, 179 size_t region_max_size, 180 uint min_pages); 181 182 // Method for tracing page sizes returned by the above method; enabled by 183 // TracePageSizes. The region_{min,max}_size parameters should be the values 184 // passed to page_size_for_region() and page_size should be the result of that 185 // call. The (optional) base and size parameters should come from the 186 // ReservedSpace base() and size() methods. 187 static void trace_page_sizes(const char* str, const size_t region_min_size, 188 const size_t region_max_size, 189 const size_t page_size, 190 const char* base = NULL, 191 const size_t size = 0) PRODUCT_RETURN; 192 193 static int vm_allocation_granularity(); 194 static char* reserve_memory(size_t bytes, char* addr = 0, 195 size_t alignment_hint = 0); 196 static char* attempt_reserve_memory_at(size_t bytes, char* addr); 197 static void split_reserved_memory(char *base, size_t size, 198 size_t split, bool realloc); 199 static bool commit_memory(char* addr, size_t bytes); 200 static bool commit_memory(char* addr, size_t size, size_t alignment_hint); 201 static bool uncommit_memory(char* addr, size_t bytes); 202 static bool release_memory(char* addr, size_t bytes); 203 static bool protect_memory(char* addr, size_t bytes); 204 static bool guard_memory(char* addr, size_t bytes); 205 static bool unguard_memory(char* addr, size_t bytes); 206 static char* map_memory(int fd, const char* file_name, size_t file_offset, 207 char *addr, size_t bytes, bool read_only = false, 208 bool allow_exec = false); 209 static char* remap_memory(int fd, const char* file_name, size_t file_offset, 210 char *addr, size_t bytes, bool read_only, 211 bool allow_exec); 212 static bool unmap_memory(char *addr, size_t bytes); 213 static void free_memory(char *addr, size_t bytes); 214 static void realign_memory(char *addr, size_t bytes, size_t alignment_hint); 215 216 // NUMA-specific interface 217 static void numa_make_local(char *addr, size_t bytes); 218 static void numa_make_global(char *addr, size_t bytes); 219 static size_t numa_get_groups_num(); 220 static size_t numa_get_leaf_groups(int *ids, size_t size); 221 static bool numa_topology_changed(); 222 static int numa_get_group_id(); 223 224 // Page manipulation 225 struct page_info { 226 size_t size; 227 int lgrp_id; 228 }; 229 static bool get_page_info(char *start, page_info* info); 230 static char* scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found); 231 232 static char* non_memory_address_word(); 233 // reserve, commit and pin the entire memory region 234 static char* reserve_memory_special(size_t size); 235 static bool release_memory_special(char* addr, size_t bytes); 236 static bool large_page_init(); 237 static size_t large_page_size(); 238 static bool can_commit_large_page_memory(); 239 240 // OS interface to polling page 241 static address get_polling_page() { return _polling_page; } 242 static void set_polling_page(address page) { _polling_page = page; } 243 static bool is_poll_address(address addr) { return addr >= _polling_page && addr < (_polling_page + os::vm_page_size()); } 244 static void make_polling_page_unreadable(); 245 static void make_polling_page_readable(); 246 247 // Routines used to serialize the thread state without using membars 248 static void serialize_thread_states(); 249 250 // Since we write to the serialize page from every thread, we 251 // want stores to be on unique cache lines whenever possible 252 // in order to minimize CPU cross talk. We pre-compute the 253 // amount to shift the thread* to make this offset unique to 254 // each thread. 255 static int get_serialize_page_shift_count() { 256 return SerializePageShiftCount; 257 } 258 259 static void set_serialize_page_mask(uintptr_t mask) { 260 _serialize_page_mask = mask; 261 } 262 263 static unsigned int get_serialize_page_mask() { 264 return _serialize_page_mask; 265 } 266 267 static void set_memory_serialize_page(address page); 268 269 static address get_memory_serialize_page() { 270 return (address)_mem_serialize_page; 271 } 272 273 static inline void write_memory_serialize_page(JavaThread *thread) { 274 uintptr_t page_offset = ((uintptr_t)thread >> 275 get_serialize_page_shift_count()) & 276 get_serialize_page_mask(); 277 *(volatile int32_t *)((uintptr_t)_mem_serialize_page+page_offset) = 1; 278 } 279 280 static bool is_memory_serialize_page(JavaThread *thread, address addr) { 281 address thr_addr; 282 if (UseMembar) return false; 283 // Calculate thread specific address 284 if (thread == NULL) return false; 285 // TODO-FIXME: some platforms mask off faulting addresses to the base pagesize. 286 // Instead of using a test for equality we should probably use something 287 // of the form: 288 // return ((_mem_serialize_page ^ addr) & -pagesize) == 0 289 // 290 thr_addr = (address)(((uintptr_t)thread >> 291 get_serialize_page_shift_count()) & 292 get_serialize_page_mask()) + (uintptr_t)_mem_serialize_page; 293 return (thr_addr == addr); 294 } 295 296 static void block_on_serialize_page_trap(); 297 298 // threads 299 300 enum ThreadType { 301 vm_thread, 302 cgc_thread, // Concurrent GC thread 303 pgc_thread, // Parallel GC thread 304 java_thread, 305 compiler_thread, 306 watcher_thread 307 }; 308 309 static bool create_thread(Thread* thread, 310 ThreadType thr_type, 311 size_t stack_size = 0); 312 static bool create_main_thread(JavaThread* thread); 313 static bool create_attached_thread(JavaThread* thread); 314 static void pd_start_thread(Thread* thread); 315 static void start_thread(Thread* thread); 316 317 static void initialize_thread(); 318 static void free_thread(OSThread* osthread); 319 320 // thread id on Linux/64bit is 64bit, on Windows and Solaris, it's 32bit 321 static intx current_thread_id(); 322 static int current_process_id(); 323 // hpi::read for calls from non native state 324 // For performance, hpi::read is only callable from _thread_in_native 325 static size_t read(int fd, void *buf, unsigned int nBytes); 326 static int sleep(Thread* thread, jlong ms, bool interruptable); 327 static int naked_sleep(); 328 static void infinite_sleep(); // never returns, use with CAUTION 329 static void yield(); // Yields to all threads with same priority 330 enum YieldResult { 331 YIELD_SWITCHED = 1, // caller descheduled, other ready threads exist & ran 332 YIELD_NONEREADY = 0, // No other runnable/ready threads. 333 // platform-specific yield return immediately 334 YIELD_UNKNOWN = -1 // Unknown: platform doesn't support _SWITCHED or _NONEREADY 335 // YIELD_SWITCHED and YIELD_NONREADY imply the platform supports a "strong" 336 // yield that can be used in lieu of blocking. 337 } ; 338 static YieldResult NakedYield () ; 339 static void yield_all(int attempts = 0); // Yields to all other threads including lower priority 340 static void loop_breaker(int attempts); // called from within tight loops to possibly influence time-sharing 341 static OSReturn set_priority(Thread* thread, ThreadPriority priority); 342 static OSReturn get_priority(const Thread* const thread, ThreadPriority& priority); 343 344 static void interrupt(Thread* thread); 345 static bool is_interrupted(Thread* thread, bool clear_interrupted); 346 347 static int pd_self_suspend_thread(Thread* thread); 348 349 static ExtendedPC fetch_frame_from_context(void* ucVoid, intptr_t** sp, intptr_t** fp); 350 static frame fetch_frame_from_context(void* ucVoid); 351 352 static ExtendedPC get_thread_pc(Thread *thread); 353 static void breakpoint(); 354 355 static address current_stack_pointer(); 356 static address current_stack_base(); 357 static size_t current_stack_size(); 358 359 static int message_box(const char* title, const char* message); 360 static char* do_you_want_to_debug(const char* message); 361 362 // run cmd in a separate process and return its exit code; or -1 on failures 363 static int fork_and_exec(char *cmd); 364 365 // Set file to send error reports. 366 static void set_error_file(const char *logfile); 367 368 // os::exit() is merged with vm_exit() 369 // static void exit(int num); 370 371 // Terminate the VM, but don't exit the process 372 static void shutdown(); 373 374 // Terminate with an error. Default is to generate a core file on platforms 375 // that support such things. This calls shutdown() and then aborts. 376 static void abort(bool dump_core = true); 377 378 // Die immediately, no exit hook, no abort hook, no cleanup. 379 static void die(); 380 381 // Reading directories. 382 static DIR* opendir(const char* dirname); 383 static int readdir_buf_size(const char *path); 384 static struct dirent* readdir(DIR* dirp, dirent* dbuf); 385 static int closedir(DIR* dirp); 386 387 // Dynamic library extension 388 static const char* dll_file_extension(); 389 390 static const char* get_temp_directory(); 391 static const char* get_current_directory(char *buf, int buflen); 392 393 // Symbol lookup, find nearest function name; basically it implements 394 // dladdr() for all platforms. Name of the nearest function is copied 395 // to buf. Distance from its base address is returned as offset. 396 // If function name is not found, buf[0] is set to '\0' and offset is 397 // set to -1. 398 static bool dll_address_to_function_name(address addr, char* buf, 399 int buflen, int* offset); 400 401 // Locate DLL/DSO. On success, full path of the library is copied to 402 // buf, and offset is set to be the distance between addr and the 403 // library's base address. On failure, buf[0] is set to '\0' and 404 // offset is set to -1. 405 static bool dll_address_to_library_name(address addr, char* buf, 406 int buflen, int* offset); 407 408 // Find out whether the pc is in the static code for jvm.dll/libjvm.so. 409 static bool address_is_in_vm(address addr); 410 411 // Loads .dll/.so and 412 // in case of error it checks if .dll/.so was built for the 413 // same architecture as Hotspot is running on 414 static void* dll_load(const char *name, char *ebuf, int ebuflen); 415 416 // Print out system information; they are called by fatal error handler. 417 // Output format may be different on different platforms. 418 static void print_os_info(outputStream* st); 419 static void print_cpu_info(outputStream* st); 420 static void print_memory_info(outputStream* st); 421 static void print_dll_info(outputStream* st); 422 static void print_environment_variables(outputStream* st, const char** env_list, char* buffer, int len); 423 static void print_context(outputStream* st, void* context); 424 static void print_siginfo(outputStream* st, void* siginfo); 425 static void print_signal_handlers(outputStream* st, char* buf, size_t buflen); 426 static void print_date_and_time(outputStream* st); 427 428 // The following two functions are used by fatal error handler to trace 429 // native (C) frames. They are not part of frame.hpp/frame.cpp because 430 // frame.hpp/cpp assume thread is JavaThread, and also because different 431 // OS/compiler may have different convention or provide different API to 432 // walk C frames. 433 // 434 // We don't attempt to become a debugger, so we only follow frames if that 435 // does not require a lookup in the unwind table, which is part of the binary 436 // file but may be unsafe to read after a fatal error. So on x86, we can 437 // only walk stack if %ebp is used as frame pointer; on ia64, it's not 438 // possible to walk C stack without having the unwind table. 439 static bool is_first_C_frame(frame *fr); 440 static frame get_sender_for_C_frame(frame *fr); 441 442 // return current frame. pc() and sp() are set to NULL on failure. 443 static frame current_frame(); 444 445 static void print_hex_dump(outputStream* st, address start, address end, int unitsize); 446 447 // returns a string to describe the exception/signal; 448 // returns NULL if exception_code is not an OS exception/signal. 449 static const char* exception_name(int exception_code, char* buf, size_t buflen); 450 451 // Returns native Java library, loads if necessary 452 static void* native_java_library(); 453 454 // Fills in path to jvm.dll/libjvm.so (this info used to find hpi). 455 static void jvm_path(char *buf, jint buflen); 456 457 // JNI names 458 static void print_jni_name_prefix_on(outputStream* st, int args_size); 459 static void print_jni_name_suffix_on(outputStream* st, int args_size); 460 461 // File conventions 462 static const char* file_separator(); 463 static const char* line_separator(); 464 static const char* path_separator(); 465 466 // Init os specific system properties values 467 static void init_system_properties_values(); 468 469 // IO operations, non-JVM_ version. 470 static int stat(const char* path, struct stat* sbuf); 471 static bool dir_is_empty(const char* path); 472 473 // IO operations on binary files 474 static int create_binary_file(const char* path, bool rewrite_existing); 475 static jlong current_file_offset(int fd); 476 static jlong seek_to_file_offset(int fd, jlong offset); 477 478 // Thread Local Storage 479 static int allocate_thread_local_storage(); 480 static void thread_local_storage_at_put(int index, void* value); 481 static void* thread_local_storage_at(int index); 482 static void free_thread_local_storage(int index); 483 484 // General allocation (must be MT-safe) 485 static void* malloc (size_t size); 486 static void* realloc (void *memblock, size_t size); 487 static void free (void *memblock); 488 static bool check_heap(bool force = false); // verify C heap integrity 489 static char* strdup(const char *); // Like strdup 490 491#ifndef PRODUCT 492 static int num_mallocs; // # of calls to malloc/realloc 493 static size_t alloc_bytes; // # of bytes allocated 494 static int num_frees; // # of calls to free 495#endif 496 497 // Printing 64 bit integers 498 static const char* jlong_format_specifier(); 499 static const char* julong_format_specifier(); 500 501 // Support for signals (see JVM_RaiseSignal, JVM_RegisterSignal) 502 static void signal_init(); 503 static void signal_init_pd(); 504 static void signal_notify(int signal_number); 505 static void* signal(int signal_number, void* handler); 506 static void signal_raise(int signal_number); 507 static int signal_wait(); 508 static int signal_lookup(); 509 static void* user_handler(); 510 static void terminate_signal_thread(); 511 static int sigexitnum_pd(); 512 513 // random number generation 514 static long random(); // return 32bit pseudorandom number 515 static void init_random(long initval); // initialize random sequence 516 517 // Structured OS Exception support 518 static void os_exception_wrapper(java_call_t f, JavaValue* value, methodHandle* method, JavaCallArguments* args, Thread* thread); 519 520 // JVMTI & JVM monitoring and management support 521 // The thread_cpu_time() and current_thread_cpu_time() are only 522 // supported if is_thread_cpu_time_supported() returns true. 523 // They are not supported on Solaris T1. 524 525 // Thread CPU Time - return the fast estimate on a platform 526 // On Solaris - call gethrvtime (fast) - user time only 527 // On Linux - fast clock_gettime where available - user+sys 528 // - otherwise: very slow /proc fs - user+sys 529 // On Windows - GetThreadTimes - user+sys 530 static jlong current_thread_cpu_time(); 531 static jlong thread_cpu_time(Thread* t); 532 533 // Thread CPU Time with user_sys_cpu_time parameter. 534 // 535 // If user_sys_cpu_time is true, user+sys time is returned. 536 // Otherwise, only user time is returned 537 static jlong current_thread_cpu_time(bool user_sys_cpu_time); 538 static jlong thread_cpu_time(Thread* t, bool user_sys_cpu_time); 539 540 // Return a bunch of info about the timers. 541 // Note that the returned info for these two functions may be different 542 // on some platforms 543 static void current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr); 544 static void thread_cpu_time_info(jvmtiTimerInfo *info_ptr); 545 546 static bool is_thread_cpu_time_supported(); 547 548 // System loadavg support. Returns -1 if load average cannot be obtained. 549 static int loadavg(double loadavg[], int nelem); 550 551 // Hook for os specific jvm options that we don't want to abort on seeing 552 static bool obsolete_option(const JavaVMOption *option); 553 554 // Platform dependent stuff 555 #include "incls/_os_pd.hpp.incl" 556 557 // debugging support (mostly used by debug.cpp) 558 static bool find(address pc) PRODUCT_RETURN0; // OS specific function to make sense out of an address 559 560 static bool dont_yield(); // when true, JVM_Yield() is nop 561 static void print_statistics(); 562 563 // Thread priority helpers (implemented in OS-specific part) 564 static OSReturn set_native_priority(Thread* thread, int native_prio); 565 static OSReturn get_native_priority(const Thread* const thread, int* priority_ptr); 566 static int java_to_os_priority[MaxPriority + 1]; 567 // Hint to the underlying OS that a task switch would not be good. 568 // Void return because it's a hint and can fail. 569 static void hint_no_preempt(); 570 571 // Used at creation if requested by the diagnostic flag PauseAtStartup. 572 // Causes the VM to wait until an external stimulus has been applied 573 // (for Unix, that stimulus is a signal, for Windows, an external 574 // ResumeThread call) 575 static void pause(); 576 577 protected: 578 static long _rand_seed; // seed for random number generator 579 static int _processor_count; // number of processors 580 581 static char* format_boot_path(const char* format_string, 582 const char* home, 583 int home_len, 584 char fileSep, 585 char pathSep); 586 static bool set_boot_path(char fileSep, char pathSep); 587}; 588 589// Note that "PAUSE" is almost always used with synchronization 590// so arguably we should provide Atomic::SpinPause() instead 591// of the global SpinPause() with C linkage. 592// It'd also be eligible for inlining on many platforms. 593 594extern "C" int SpinPause () ; 595extern "C" int SafeFetch32 (int * adr, int errValue) ; 596extern "C" intptr_t SafeFetchN (intptr_t * adr, intptr_t errValue) ; 597