os.hpp revision 61:5a76ab815e34
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 size_t _page_sizes[page_sizes_max]; 70 71 static void init_page_sizes(size_t default_page_size) { 72 _page_sizes[0] = default_page_size; 73 _page_sizes[1] = 0; // sentinel 74 } 75 76 public: 77 78 static void init(void); // Called before command line parsing 79 static jint init_2(void); // Called after command line parsing 80 81 // File names are case-insensitive on windows only 82 // Override me as needed 83 static int file_name_strcmp(const char* s1, const char* s2); 84 85 static bool getenv(const char* name, char* buffer, int len); 86 static bool have_special_privileges(); 87 88 static jlong javaTimeMillis(); 89 static jlong javaTimeNanos(); 90 static void javaTimeNanos_info(jvmtiTimerInfo *info_ptr); 91 static void run_periodic_checks(); 92 93 94 // Returns the elapsed time in seconds since the vm started. 95 static double elapsedTime(); 96 97 // Returns real time in seconds since an arbitrary point 98 // in the past. 99 static bool getTimesSecs(double* process_real_time, 100 double* process_user_time, 101 double* process_system_time); 102 103 // Interface to the performance counter 104 static jlong elapsed_counter(); 105 static jlong elapsed_frequency(); 106 107 // Return current local time in a string (YYYY-MM-DD HH:MM:SS). 108 // It is MT safe, but not async-safe, as reading time zone 109 // information may require a lock on some platforms. 110 static char* local_time_string(char *buf, size_t buflen); 111 // Fill in buffer with current local time as an ISO-8601 string. 112 // E.g., YYYY-MM-DDThh:mm:ss.mmm+zzzz. 113 // Returns buffer, or NULL if it failed. 114 static char* iso8601_time(char* buffer, size_t buffer_length); 115 116 // Interface for detecting multiprocessor system 117 static inline bool is_MP() { 118 assert(_processor_count > 0, "invalid processor count"); 119 return _processor_count > 1; 120 } 121 static julong available_memory(); 122 static julong physical_memory(); 123 static julong allocatable_physical_memory(julong size); 124 static bool is_server_class_machine(); 125 126 // number of CPUs 127 static int processor_count() { 128 return _processor_count; 129 } 130 131 // Returns the number of CPUs this process is currently allowed to run on. 132 // Note that on some OSes this can change dynamically. 133 static int active_processor_count(); 134 135 // Bind processes to processors. 136 // This is a two step procedure: 137 // first you generate a distribution of processes to processors, 138 // then you bind processes according to that distribution. 139 // Compute a distribution for number of processes to processors. 140 // Stores the processor id's into the distribution array argument. 141 // Returns true if it worked, false if it didn't. 142 static bool distribute_processes(uint length, uint* distribution); 143 // Binds the current process to a processor. 144 // Returns true if it worked, false if it didn't. 145 static bool bind_to_processor(uint processor_id); 146 147 // Interface for stack banging (predetect possible stack overflow for 148 // exception processing) There are guard pages, and above that shadow 149 // pages for stack overflow checking. 150 static bool uses_stack_guard_pages(); 151 static bool allocate_stack_guard_pages(); 152 static void bang_stack_shadow_pages(); 153 static bool stack_shadow_pages_available(Thread *thread, methodHandle method); 154 155 // OS interface to Virtual Memory 156 157 // Return the default page size. 158 static int vm_page_size(); 159 160 // Return the page size to use for a region of memory. The min_pages argument 161 // is a hint intended to limit fragmentation; it says the returned page size 162 // should be <= region_max_size / min_pages. Because min_pages is a hint, 163 // this routine may return a size larger than region_max_size / min_pages. 164 // 165 // The current implementation ignores min_pages if a larger page size is an 166 // exact multiple of both region_min_size and region_max_size. This allows 167 // larger pages to be used when doing so would not cause fragmentation; in 168 // particular, a single page can be used when region_min_size == 169 // region_max_size == a supported page size. 170 static size_t page_size_for_region(size_t region_min_size, 171 size_t region_max_size, 172 uint min_pages); 173 174 // Method for tracing page sizes returned by the above method; enabled by 175 // TracePageSizes. The region_{min,max}_size parameters should be the values 176 // passed to page_size_for_region() and page_size should be the result of that 177 // call. The (optional) base and size parameters should come from the 178 // ReservedSpace base() and size() methods. 179 static void trace_page_sizes(const char* str, const size_t region_min_size, 180 const size_t region_max_size, 181 const size_t page_size, 182 const char* base = NULL, 183 const size_t size = 0) PRODUCT_RETURN; 184 185 static int vm_allocation_granularity(); 186 static char* reserve_memory(size_t bytes, char* addr = 0, 187 size_t alignment_hint = 0); 188 static char* attempt_reserve_memory_at(size_t bytes, char* addr); 189 static void split_reserved_memory(char *base, size_t size, 190 size_t split, bool realloc); 191 static bool commit_memory(char* addr, size_t bytes); 192 static bool commit_memory(char* addr, size_t size, size_t alignment_hint); 193 static bool uncommit_memory(char* addr, size_t bytes); 194 static bool release_memory(char* addr, size_t bytes); 195 static bool protect_memory(char* addr, size_t bytes); 196 static bool guard_memory(char* addr, size_t bytes); 197 static bool unguard_memory(char* addr, size_t bytes); 198 static char* map_memory(int fd, const char* file_name, size_t file_offset, 199 char *addr, size_t bytes, bool read_only = false, 200 bool allow_exec = false); 201 static char* remap_memory(int fd, const char* file_name, size_t file_offset, 202 char *addr, size_t bytes, bool read_only, 203 bool allow_exec); 204 static bool unmap_memory(char *addr, size_t bytes); 205 static void free_memory(char *addr, size_t bytes); 206 static void realign_memory(char *addr, size_t bytes, size_t alignment_hint); 207 208 // NUMA-specific interface 209 static void numa_make_local(char *addr, size_t bytes); 210 static void numa_make_global(char *addr, size_t bytes); 211 static size_t numa_get_groups_num(); 212 static size_t numa_get_leaf_groups(int *ids, size_t size); 213 static bool numa_topology_changed(); 214 static int numa_get_group_id(); 215 216 // Page manipulation 217 struct page_info { 218 size_t size; 219 int lgrp_id; 220 }; 221 static bool get_page_info(char *start, page_info* info); 222 static char* scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found); 223 224 static char* non_memory_address_word(); 225 // reserve, commit and pin the entire memory region 226 static char* reserve_memory_special(size_t size); 227 static bool release_memory_special(char* addr, size_t bytes); 228 static bool large_page_init(); 229 static size_t large_page_size(); 230 static bool can_commit_large_page_memory(); 231 232 // OS interface to polling page 233 static address get_polling_page() { return _polling_page; } 234 static void set_polling_page(address page) { _polling_page = page; } 235 static bool is_poll_address(address addr) { return addr >= _polling_page && addr < (_polling_page + os::vm_page_size()); } 236 static void make_polling_page_unreadable(); 237 static void make_polling_page_readable(); 238 239 // Routines used to serialize the thread state without using membars 240 static void serialize_thread_states(); 241 242 // Since we write to the serialize page from every thread, we 243 // want stores to be on unique cache lines whenever possible 244 // in order to minimize CPU cross talk. We pre-compute the 245 // amount to shift the thread* to make this offset unique to 246 // each thread. 247 static int get_serialize_page_shift_count() { 248 return SerializePageShiftCount; 249 } 250 251 static void set_serialize_page_mask(uintptr_t mask) { 252 _serialize_page_mask = mask; 253 } 254 255 static unsigned int get_serialize_page_mask() { 256 return _serialize_page_mask; 257 } 258 259 static void set_memory_serialize_page(address page); 260 261 static address get_memory_serialize_page() { 262 return (address)_mem_serialize_page; 263 } 264 265 static inline void write_memory_serialize_page(JavaThread *thread) { 266 uintptr_t page_offset = ((uintptr_t)thread >> 267 get_serialize_page_shift_count()) & 268 get_serialize_page_mask(); 269 *(volatile int32_t *)((uintptr_t)_mem_serialize_page+page_offset) = 1; 270 } 271 272 static bool is_memory_serialize_page(JavaThread *thread, address addr) { 273 address thr_addr; 274 if (UseMembar) return false; 275 // Calculate thread specific address 276 if (thread == NULL) return false; 277 // TODO-FIXME: some platforms mask off faulting addresses to the base pagesize. 278 // Instead of using a test for equality we should probably use something 279 // of the form: 280 // return ((_mem_serialize_page ^ addr) & -pagesize) == 0 281 // 282 thr_addr = (address)(((uintptr_t)thread >> 283 get_serialize_page_shift_count()) & 284 get_serialize_page_mask()) + (uintptr_t)_mem_serialize_page; 285 return (thr_addr == addr); 286 } 287 288 static void block_on_serialize_page_trap(); 289 290 // threads 291 292 enum ThreadType { 293 vm_thread, 294 cgc_thread, // Concurrent GC thread 295 pgc_thread, // Parallel GC thread 296 java_thread, 297 compiler_thread, 298 watcher_thread 299 }; 300 301 static bool create_thread(Thread* thread, 302 ThreadType thr_type, 303 size_t stack_size = 0); 304 static bool create_main_thread(JavaThread* thread); 305 static bool create_attached_thread(JavaThread* thread); 306 static void pd_start_thread(Thread* thread); 307 static void start_thread(Thread* thread); 308 309 static void initialize_thread(); 310 static void free_thread(OSThread* osthread); 311 312 // thread id on Linux/64bit is 64bit, on Windows and Solaris, it's 32bit 313 static intx current_thread_id(); 314 static int current_process_id(); 315 // hpi::read for calls from non native state 316 // For performance, hpi::read is only callable from _thread_in_native 317 static size_t read(int fd, void *buf, unsigned int nBytes); 318 static int sleep(Thread* thread, jlong ms, bool interruptable); 319 static int naked_sleep(); 320 static void infinite_sleep(); // never returns, use with CAUTION 321 static void yield(); // Yields to all threads with same priority 322 enum YieldResult { 323 YIELD_SWITCHED = 1, // caller descheduled, other ready threads exist & ran 324 YIELD_NONEREADY = 0, // No other runnable/ready threads. 325 // platform-specific yield return immediately 326 YIELD_UNKNOWN = -1 // Unknown: platform doesn't support _SWITCHED or _NONEREADY 327 // YIELD_SWITCHED and YIELD_NONREADY imply the platform supports a "strong" 328 // yield that can be used in lieu of blocking. 329 } ; 330 static YieldResult NakedYield () ; 331 static void yield_all(int attempts = 0); // Yields to all other threads including lower priority 332 static void loop_breaker(int attempts); // called from within tight loops to possibly influence time-sharing 333 static OSReturn set_priority(Thread* thread, ThreadPriority priority); 334 static OSReturn get_priority(const Thread* const thread, ThreadPriority& priority); 335 336 static void interrupt(Thread* thread); 337 static bool is_interrupted(Thread* thread, bool clear_interrupted); 338 339 static int pd_self_suspend_thread(Thread* thread); 340 341 static ExtendedPC fetch_frame_from_context(void* ucVoid, intptr_t** sp, intptr_t** fp); 342 static frame fetch_frame_from_context(void* ucVoid); 343 344 static ExtendedPC get_thread_pc(Thread *thread); 345 static void breakpoint(); 346 347 static address current_stack_pointer(); 348 static address current_stack_base(); 349 static size_t current_stack_size(); 350 351 static int message_box(const char* title, const char* message); 352 static char* do_you_want_to_debug(const char* message); 353 354 // run cmd in a separate process and return its exit code; or -1 on failures 355 static int fork_and_exec(char *cmd); 356 357 // Set file to send error reports. 358 static void set_error_file(const char *logfile); 359 360 // os::exit() is merged with vm_exit() 361 // static void exit(int num); 362 363 // Terminate the VM, but don't exit the process 364 static void shutdown(); 365 366 // Terminate with an error. Default is to generate a core file on platforms 367 // that support such things. This calls shutdown() and then aborts. 368 static void abort(bool dump_core = true); 369 370 // Die immediately, no exit hook, no abort hook, no cleanup. 371 static void die(); 372 373 // Reading directories. 374 static DIR* opendir(const char* dirname); 375 static int readdir_buf_size(const char *path); 376 static struct dirent* readdir(DIR* dirp, dirent* dbuf); 377 static int closedir(DIR* dirp); 378 379 // Dynamic library extension 380 static const char* dll_file_extension(); 381 382 static const char* get_temp_directory(); 383 static const char* get_current_directory(char *buf, int buflen); 384 385 // Symbol lookup, find nearest function name; basically it implements 386 // dladdr() for all platforms. Name of the nearest function is copied 387 // to buf. Distance from its base address is returned as offset. 388 // If function name is not found, buf[0] is set to '\0' and offset is 389 // set to -1. 390 static bool dll_address_to_function_name(address addr, char* buf, 391 int buflen, int* offset); 392 393 // Locate DLL/DSO. On success, full path of the library is copied to 394 // buf, and offset is set to be the distance between addr and the 395 // library's base address. On failure, buf[0] is set to '\0' and 396 // offset is set to -1. 397 static bool dll_address_to_library_name(address addr, char* buf, 398 int buflen, int* offset); 399 400 // Find out whether the pc is in the static code for jvm.dll/libjvm.so. 401 static bool address_is_in_vm(address addr); 402 403 // Loads .dll/.so and 404 // in case of error it checks if .dll/.so was built for the 405 // same architecture as Hotspot is running on 406 static void* dll_load(const char *name, char *ebuf, int ebuflen); 407 408 // Print out system information; they are called by fatal error handler. 409 // Output format may be different on different platforms. 410 static void print_os_info(outputStream* st); 411 static void print_cpu_info(outputStream* st); 412 static void print_memory_info(outputStream* st); 413 static void print_dll_info(outputStream* st); 414 static void print_environment_variables(outputStream* st, const char** env_list, char* buffer, int len); 415 static void print_context(outputStream* st, void* context); 416 static void print_siginfo(outputStream* st, void* siginfo); 417 static void print_signal_handlers(outputStream* st, char* buf, size_t buflen); 418 static void print_date_and_time(outputStream* st); 419 420 // The following two functions are used by fatal error handler to trace 421 // native (C) frames. They are not part of frame.hpp/frame.cpp because 422 // frame.hpp/cpp assume thread is JavaThread, and also because different 423 // OS/compiler may have different convention or provide different API to 424 // walk C frames. 425 // 426 // We don't attempt to become a debugger, so we only follow frames if that 427 // does not require a lookup in the unwind table, which is part of the binary 428 // file but may be unsafe to read after a fatal error. So on x86, we can 429 // only walk stack if %ebp is used as frame pointer; on ia64, it's not 430 // possible to walk C stack without having the unwind table. 431 static bool is_first_C_frame(frame *fr); 432 static frame get_sender_for_C_frame(frame *fr); 433 434 // return current frame. pc() and sp() are set to NULL on failure. 435 static frame current_frame(); 436 437 static void print_hex_dump(outputStream* st, address start, address end, int unitsize); 438 439 // returns a string to describe the exception/signal; 440 // returns NULL if exception_code is not an OS exception/signal. 441 static const char* exception_name(int exception_code, char* buf, size_t buflen); 442 443 // Returns native Java library, loads if necessary 444 static void* native_java_library(); 445 446 // Fills in path to jvm.dll/libjvm.so (this info used to find hpi). 447 static void jvm_path(char *buf, jint buflen); 448 449 // JNI names 450 static void print_jni_name_prefix_on(outputStream* st, int args_size); 451 static void print_jni_name_suffix_on(outputStream* st, int args_size); 452 453 // File conventions 454 static const char* file_separator(); 455 static const char* line_separator(); 456 static const char* path_separator(); 457 458 // Init os specific system properties values 459 static void init_system_properties_values(); 460 461 // IO operations, non-JVM_ version. 462 static int stat(const char* path, struct stat* sbuf); 463 static bool dir_is_empty(const char* path); 464 465 // IO operations on binary files 466 static int create_binary_file(const char* path, bool rewrite_existing); 467 static jlong current_file_offset(int fd); 468 static jlong seek_to_file_offset(int fd, jlong offset); 469 470 // Thread Local Storage 471 static int allocate_thread_local_storage(); 472 static void thread_local_storage_at_put(int index, void* value); 473 static void* thread_local_storage_at(int index); 474 static void free_thread_local_storage(int index); 475 476 // General allocation (must be MT-safe) 477 static void* malloc (size_t size); 478 static void* realloc (void *memblock, size_t size); 479 static void free (void *memblock); 480 static bool check_heap(bool force = false); // verify C heap integrity 481 static char* strdup(const char *); // Like strdup 482 483#ifndef PRODUCT 484 static int num_mallocs; // # of calls to malloc/realloc 485 static size_t alloc_bytes; // # of bytes allocated 486 static int num_frees; // # of calls to free 487#endif 488 489 // Printing 64 bit integers 490 static const char* jlong_format_specifier(); 491 static const char* julong_format_specifier(); 492 493 // Support for signals (see JVM_RaiseSignal, JVM_RegisterSignal) 494 static void signal_init(); 495 static void signal_init_pd(); 496 static void signal_notify(int signal_number); 497 static void* signal(int signal_number, void* handler); 498 static void signal_raise(int signal_number); 499 static int signal_wait(); 500 static int signal_lookup(); 501 static void* user_handler(); 502 static void terminate_signal_thread(); 503 static int sigexitnum_pd(); 504 505 // random number generation 506 static long random(); // return 32bit pseudorandom number 507 static void init_random(long initval); // initialize random sequence 508 509 // Structured OS Exception support 510 static void os_exception_wrapper(java_call_t f, JavaValue* value, methodHandle* method, JavaCallArguments* args, Thread* thread); 511 512 // JVMTI & JVM monitoring and management support 513 // The thread_cpu_time() and current_thread_cpu_time() are only 514 // supported if is_thread_cpu_time_supported() returns true. 515 // They are not supported on Solaris T1. 516 517 // Thread CPU Time - return the fast estimate on a platform 518 // On Solaris - call gethrvtime (fast) - user time only 519 // On Linux - fast clock_gettime where available - user+sys 520 // - otherwise: very slow /proc fs - user+sys 521 // On Windows - GetThreadTimes - user+sys 522 static jlong current_thread_cpu_time(); 523 static jlong thread_cpu_time(Thread* t); 524 525 // Thread CPU Time with user_sys_cpu_time parameter. 526 // 527 // If user_sys_cpu_time is true, user+sys time is returned. 528 // Otherwise, only user time is returned 529 static jlong current_thread_cpu_time(bool user_sys_cpu_time); 530 static jlong thread_cpu_time(Thread* t, bool user_sys_cpu_time); 531 532 // Return a bunch of info about the timers. 533 // Note that the returned info for these two functions may be different 534 // on some platforms 535 static void current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr); 536 static void thread_cpu_time_info(jvmtiTimerInfo *info_ptr); 537 538 static bool is_thread_cpu_time_supported(); 539 540 // System loadavg support. Returns -1 if load average cannot be obtained. 541 static int loadavg(double loadavg[], int nelem); 542 543 // Hook for os specific jvm options that we don't want to abort on seeing 544 static bool obsolete_option(const JavaVMOption *option); 545 546 // Platform dependent stuff 547 #include "incls/_os_pd.hpp.incl" 548 549 // debugging support (mostly used by debug.cpp) 550 static bool find(address pc) PRODUCT_RETURN0; // OS specific function to make sense out of an address 551 552 static bool dont_yield(); // when true, JVM_Yield() is nop 553 static void print_statistics(); 554 555 // Thread priority helpers (implemented in OS-specific part) 556 static OSReturn set_native_priority(Thread* thread, int native_prio); 557 static OSReturn get_native_priority(const Thread* const thread, int* priority_ptr); 558 static int java_to_os_priority[MaxPriority + 1]; 559 // Hint to the underlying OS that a task switch would not be good. 560 // Void return because it's a hint and can fail. 561 static void hint_no_preempt(); 562 563 // Used at creation if requested by the diagnostic flag PauseAtStartup. 564 // Causes the VM to wait until an external stimulus has been applied 565 // (for Unix, that stimulus is a signal, for Windows, an external 566 // ResumeThread call) 567 static void pause(); 568 569 protected: 570 static long _rand_seed; // seed for random number generator 571 static int _processor_count; // number of processors 572 573 static char* format_boot_path(const char* format_string, 574 const char* home, 575 int home_len, 576 char fileSep, 577 char pathSep); 578 static bool set_boot_path(char fileSep, char pathSep); 579}; 580 581// Note that "PAUSE" is almost always used with synchronization 582// so arguably we should provide Atomic::SpinPause() instead 583// of the global SpinPause() with C linkage. 584// It'd also be eligible for inlining on many platforms. 585 586extern "C" int SpinPause () ; 587extern "C" int SafeFetch32 (int * adr, int errValue) ; 588extern "C" intptr_t SafeFetchN (intptr_t * adr, intptr_t errValue) ; 589