os.hpp revision 548:773234c55e8c
150276Speter/* 250276Speter * Copyright 1997-2008 Sun Microsystems, Inc. All Rights Reserved. 350276Speter * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 450276Speter * 5174993Srafan * This code is free software; you can redistribute it and/or modify it 6174993Srafan * under the terms of the GNU General Public License version 2 only, as 7174993Srafan * published by the Free Software Foundation. 862449Speter * 9174993Srafan * This code is distributed in the hope that it will be useful, but WITHOUT 1062449Speter * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11174993Srafan * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12174993Srafan * version 2 for more details (a copy is included in the LICENSE file that 13174993Srafan * accompanied this code). 14174993Srafan * 15174993Srafan * You should have received a copy of the GNU General Public License version 16174993Srafan * 2 along with this work; if not, write to the Free Software Foundation, 17174993Srafan * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18174993Srafan * 19174993Srafan * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, 20174993Srafan * CA 95054 USA or visit www.sun.com if you need additional information or 21174993Srafan * have any questions. 22174993Srafan * 23174993Srafan */ 24174993Srafan 25174993Srafan// os defines the interface to operating system; this includes traditional 26174993Srafan// OS services (time, I/O) as well as other functionality with system- 27174993Srafan// dependent code. 28174993Srafan 29174993Srafantypedef void (*dll_func)(...); 30174993Srafan 31174993Srafanclass Thread; 32174993Srafanclass JavaThread; 33174993Srafanclass Event; 34174993Srafanclass DLL; 35174993Srafanclass FileHandle; 3650276Spetertemplate<class E> class GrowableArray; 3750276Speter 3850276Speter// %%%%% Moved ThreadState, START_FN, OSThread to new osThread.hpp. -- Rose 3950276Speter 4050276Speter// Platform-independent error return values from OS functions 4162449Speterenum OSReturn { 4262449Speter OS_OK = 0, // Operation was successful 4350276Speter OS_ERR = -1, // Operation failed 4450276Speter OS_INTRPT = -2, // Operation was interrupted 4550276Speter OS_TIMEOUT = -3, // Operation timed out 4650276Speter OS_NOMEM = -5, // Operation failed for lack of memory 4750276Speter OS_NORESOURCE = -6 // Operation failed for lack of nonmemory resource 4850276Speter}; 4950276Speter 5050276Speterenum ThreadPriority { // JLS 20.20.1-3 5150276Speter NoPriority = -1, // Initial non-priority value 5250276Speter MinPriority = 1, // Minimum priority 5350276Speter NormPriority = 5, // Normal (non-daemon) priority 5450276Speter NearMaxPriority = 9, // High priority, used for VMThread 5550276Speter MaxPriority = 10 // Highest priority, used for WatcherThread 5650276Speter // ensures that VMThread doesn't starve profiler 5750276Speter}; 5850276Speter 5950276Speter// Typedef for structured exception handling support 6050276Spetertypedef void (*java_call_t)(JavaValue* value, methodHandle* method, JavaCallArguments* args, Thread* thread); 6150276Speter 6262449Speterclass os: AllStatic { 6350276Speter private: 6450276Speter enum { page_sizes_max = 9 }; // Size of _page_sizes array (8 plus a sentinel) 6550276Speter 6650276Speter static OSThread* _starting_thread; 6750276Speter static address _polling_page; 6850276Speter static volatile int32_t * _mem_serialize_page; 6950276Speter static uintptr_t _serialize_page_mask; 7050276Speter static size_t _page_sizes[page_sizes_max]; 7150276Speter 7250276Speter static void init_page_sizes(size_t default_page_size) { 7350276Speter _page_sizes[0] = default_page_size; 7450276Speter _page_sizes[1] = 0; // sentinel 7550276Speter } 7650276Speter 77174993Srafan public: 7850276Speter 7950276Speter static void init(void); // Called before command line parsing 8050276Speter static jint init_2(void); // Called after command line parsing 8150276Speter 8250276Speter // File names are case-insensitive on windows only 8350276Speter // Override me as needed 8450276Speter static int file_name_strcmp(const char* s1, const char* s2); 8550276Speter 8650276Speter static bool getenv(const char* name, char* buffer, int len); 8750276Speter static bool have_special_privileges(); 8850276Speter 8950276Speter static jlong javaTimeMillis(); 9050276Speter static jlong javaTimeNanos(); 9150276Speter static void javaTimeNanos_info(jvmtiTimerInfo *info_ptr); 9250276Speter static void run_periodic_checks(); 9350276Speter 9450276Speter 9550276Speter // Returns the elapsed time in seconds since the vm started. 9650276Speter static double elapsedTime(); 9750276Speter 9850276Speter // Returns real time in seconds since an arbitrary point 9950276Speter // in the past. 100174993Srafan static bool getTimesSecs(double* process_real_time, 10150276Speter double* process_user_time, 10250276Speter double* process_system_time); 10350276Speter 10450276Speter // Interface to the performance counter 10550276Speter static jlong elapsed_counter(); 10650276Speter static jlong elapsed_frequency(); 10750276Speter 10850276Speter // The "virtual time" of a thread is the amount of time a thread has 10950276Speter // actually run. The first function indicates whether the OS supports 11050276Speter // this functionality for the current thread, and if so: 11150276Speter // * the second enables vtime tracking (if that is required). 11250276Speter // * the third tells whether vtime is enabled. 11350276Speter // * the fourth returns the elapsed virtual time for the current 11450276Speter // thread. 11550276Speter static bool supports_vtime(); 11650276Speter static bool enable_vtime(); 11750276Speter static bool vtime_enabled(); 11850276Speter static double elapsedVTime(); 11950276Speter 12050276Speter // Return current local time in a string (YYYY-MM-DD HH:MM:SS). 12150276Speter // It is MT safe, but not async-safe, as reading time zone 12250276Speter // information may require a lock on some platforms. 12350276Speter static char* local_time_string(char *buf, size_t buflen); 12450276Speter static struct tm* localtime_pd (const time_t* clock, struct tm* res); 12550276Speter // Fill in buffer with current local time as an ISO-8601 string. 12650276Speter // E.g., YYYY-MM-DDThh:mm:ss.mmm+zzzz. 127174993Srafan // Returns buffer, or NULL if it failed. 12850276Speter static char* iso8601_time(char* buffer, size_t buffer_length); 12950276Speter 130166124Srafan // Interface for detecting multiprocessor system 13150276Speter static inline bool is_MP() { 13250276Speter assert(_processor_count > 0, "invalid processor count"); 13350276Speter return _processor_count > 1; 13450276Speter } 13550276Speter static julong available_memory(); 136166124Srafan static julong physical_memory(); 137174993Srafan static julong allocatable_physical_memory(julong size); 13850276Speter static bool is_server_class_machine(); 139166124Srafan 14050276Speter // number of CPUs 141166124Srafan static int processor_count() { 14250276Speter return _processor_count; 14350276Speter } 14450276Speter 14550276Speter // Returns the number of CPUs this process is currently allowed to run on. 146166124Srafan // Note that on some OSes this can change dynamically. 14750276Speter static int active_processor_count(); 14850276Speter 149174993Srafan // Bind processes to processors. 15050276Speter // This is a two step procedure: 151166124Srafan // first you generate a distribution of processes to processors, 15250276Speter // then you bind processes according to that distribution. 153174993Srafan // Compute a distribution for number of processes to processors. 15450276Speter // Stores the processor id's into the distribution array argument. 15550276Speter // Returns true if it worked, false if it didn't. 156166124Srafan static bool distribute_processes(uint length, uint* distribution); 15750276Speter // Binds the current process to a processor. 15850276Speter // Returns true if it worked, false if it didn't. 159174993Srafan static bool bind_to_processor(uint processor_id); 16050276Speter 16150276Speter // Interface for stack banging (predetect possible stack overflow for 162166124Srafan // exception processing) There are guard pages, and above that shadow 16350276Speter // pages for stack overflow checking. 16450276Speter static bool uses_stack_guard_pages(); 16550276Speter static bool allocate_stack_guard_pages(); 16650276Speter static void bang_stack_shadow_pages(); 16750276Speter static bool stack_shadow_pages_available(Thread *thread, methodHandle method); 168174993Srafan 16950276Speter // OS interface to Virtual Memory 170174993Srafan 17150276Speter // Return the default page size. 172166124Srafan static int vm_page_size(); 17350276Speter 17450276Speter // Return the page size to use for a region of memory. The min_pages argument 17550276Speter // is a hint intended to limit fragmentation; it says the returned page size 17650276Speter // should be <= region_max_size / min_pages. Because min_pages is a hint, 177174993Srafan // this routine may return a size larger than region_max_size / min_pages. 17850276Speter // 17950276Speter // The current implementation ignores min_pages if a larger page size is an 18050276Speter // exact multiple of both region_min_size and region_max_size. This allows 18150276Speter // larger pages to be used when doing so would not cause fragmentation; in 18250276Speter // particular, a single page can be used when region_min_size == 18350276Speter // region_max_size == a supported page size. 184166124Srafan static size_t page_size_for_region(size_t region_min_size, 185166124Srafan size_t region_max_size, 186174993Srafan uint min_pages); 18750276Speter 188174993Srafan // Method for tracing page sizes returned by the above method; enabled by 18950276Speter // TracePageSizes. The region_{min,max}_size parameters should be the values 19050276Speter // passed to page_size_for_region() and page_size should be the result of that 191174993Srafan // call. The (optional) base and size parameters should come from the 192174993Srafan // ReservedSpace base() and size() methods. 19350276Speter static void trace_page_sizes(const char* str, const size_t region_min_size, 19450276Speter const size_t region_max_size, 19550276Speter const size_t page_size, 19650276Speter const char* base = NULL, 197174993Srafan const size_t size = 0) PRODUCT_RETURN; 19850276Speter 19950276Speter static int vm_allocation_granularity(); 200174993Srafan static char* reserve_memory(size_t bytes, char* addr = 0, 20150276Speter size_t alignment_hint = 0); 202174993Srafan static char* attempt_reserve_memory_at(size_t bytes, char* addr); 20350276Speter static void split_reserved_memory(char *base, size_t size, 204166124Srafan size_t split, bool realloc); 20550276Speter static bool commit_memory(char* addr, size_t bytes); 20650276Speter static bool commit_memory(char* addr, size_t size, size_t alignment_hint); 207174993Srafan static bool uncommit_memory(char* addr, size_t bytes); 20850276Speter static bool release_memory(char* addr, size_t bytes); 20950276Speter 21050276Speter enum ProtType { MEM_PROT_NONE, MEM_PROT_READ, MEM_PROT_RW, MEM_PROT_RWX }; 21150276Speter static bool protect_memory(char* addr, size_t bytes, ProtType prot, 21250276Speter bool is_committed = true); 213174993Srafan 21450276Speter static bool guard_memory(char* addr, size_t bytes); 215174993Srafan static bool unguard_memory(char* addr, size_t bytes); 216174993Srafan static char* map_memory(int fd, const char* file_name, size_t file_offset, 217174993Srafan char *addr, size_t bytes, bool read_only = false, 218174993Srafan bool allow_exec = false); 21950276Speter static char* remap_memory(int fd, const char* file_name, size_t file_offset, 22050276Speter char *addr, size_t bytes, bool read_only, 22150276Speter bool allow_exec); 22250276Speter static bool unmap_memory(char *addr, size_t bytes); 223166124Srafan static void free_memory(char *addr, size_t bytes); 22450276Speter static void realign_memory(char *addr, size_t bytes, size_t alignment_hint); 225174993Srafan 22650276Speter // NUMA-specific interface 227174993Srafan static bool numa_has_static_binding(); 22850276Speter static bool numa_has_group_homing(); 22950276Speter static void numa_make_local(char *addr, size_t bytes, int lgrp_hint); 23050276Speter static void numa_make_global(char *addr, size_t bytes); 23150276Speter static size_t numa_get_groups_num(); 23250276Speter static size_t numa_get_leaf_groups(int *ids, size_t size); 233166124Srafan static bool numa_topology_changed(); 23450276Speter static int numa_get_group_id(); 235174993Srafan 23650276Speter // Page manipulation 237166124Srafan struct page_info { 23850276Speter size_t size; 23950276Speter int lgrp_id; 240174993Srafan }; 24150276Speter static bool get_page_info(char *start, page_info* info); 24250276Speter static char* scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found); 243174993Srafan 24450276Speter static char* non_memory_address_word(); 245174993Srafan // reserve, commit and pin the entire memory region 246174993Srafan static char* reserve_memory_special(size_t size); 247174993Srafan static bool release_memory_special(char* addr, size_t bytes); 248174993Srafan static bool large_page_init(); 249174993Srafan static size_t large_page_size(); 25050276Speter static bool can_commit_large_page_memory(); 25150276Speter static bool can_execute_large_page_memory(); 252174993Srafan 25350276Speter // OS interface to polling page 25450276Speter static address get_polling_page() { return _polling_page; } 25550276Speter static void set_polling_page(address page) { _polling_page = page; } 25650276Speter static bool is_poll_address(address addr) { return addr >= _polling_page && addr < (_polling_page + os::vm_page_size()); } 25750276Speter static void make_polling_page_unreadable(); 25850276Speter static void make_polling_page_readable(); 25950276Speter 260174993Srafan // Routines used to serialize the thread state without using membars 261174993Srafan static void serialize_thread_states(); 262174993Srafan 263174993Srafan // Since we write to the serialize page from every thread, we 26450276Speter // want stores to be on unique cache lines whenever possible 265174993Srafan // in order to minimize CPU cross talk. We pre-compute the 266174993Srafan // amount to shift the thread* to make this offset unique to 267174993Srafan // each thread. 268174993Srafan static int get_serialize_page_shift_count() { 269174993Srafan return SerializePageShiftCount; 270174993Srafan } 271174993Srafan 272174993Srafan static void set_serialize_page_mask(uintptr_t mask) { 273174993Srafan _serialize_page_mask = mask; 274174993Srafan } 275174993Srafan 276174993Srafan static unsigned int get_serialize_page_mask() { 277174993Srafan return _serialize_page_mask; 278174993Srafan } 279174993Srafan 280174993Srafan static void set_memory_serialize_page(address page); 281174993Srafan 282174993Srafan static address get_memory_serialize_page() { 283174993Srafan return (address)_mem_serialize_page; 28450276Speter } 28550276Speter 286174993Srafan static inline void write_memory_serialize_page(JavaThread *thread) { 28750276Speter uintptr_t page_offset = ((uintptr_t)thread >> 28850276Speter get_serialize_page_shift_count()) & 28950276Speter get_serialize_page_mask(); 290174993Srafan *(volatile int32_t *)((uintptr_t)_mem_serialize_page+page_offset) = 1; 29150276Speter } 292174993Srafan 293174993Srafan static bool is_memory_serialize_page(JavaThread *thread, address addr) { 294174993Srafan address thr_addr; 295 if (UseMembar) return false; 296 // Calculate thread specific address 297 if (thread == NULL) return false; 298 // TODO-FIXME: some platforms mask off faulting addresses to the base pagesize. 299 // Instead of using a test for equality we should probably use something 300 // of the form: 301 // return ((_mem_serialize_page ^ addr) & -pagesize) == 0 302 // 303 thr_addr = (address)(((uintptr_t)thread >> 304 get_serialize_page_shift_count()) & 305 get_serialize_page_mask()) + (uintptr_t)_mem_serialize_page; 306 return (thr_addr == addr); 307 } 308 309 static void block_on_serialize_page_trap(); 310 311 // threads 312 313 enum ThreadType { 314 vm_thread, 315 cgc_thread, // Concurrent GC thread 316 pgc_thread, // Parallel GC thread 317 java_thread, 318 compiler_thread, 319 watcher_thread 320 }; 321 322 static bool create_thread(Thread* thread, 323 ThreadType thr_type, 324 size_t stack_size = 0); 325 static bool create_main_thread(JavaThread* thread); 326 static bool create_attached_thread(JavaThread* thread); 327 static void pd_start_thread(Thread* thread); 328 static void start_thread(Thread* thread); 329 330 static void initialize_thread(); 331 static void free_thread(OSThread* osthread); 332 333 // thread id on Linux/64bit is 64bit, on Windows and Solaris, it's 32bit 334 static intx current_thread_id(); 335 static int current_process_id(); 336 // hpi::read for calls from non native state 337 // For performance, hpi::read is only callable from _thread_in_native 338 static size_t read(int fd, void *buf, unsigned int nBytes); 339 static int sleep(Thread* thread, jlong ms, bool interruptable); 340 static int naked_sleep(); 341 static void infinite_sleep(); // never returns, use with CAUTION 342 static void yield(); // Yields to all threads with same priority 343 enum YieldResult { 344 YIELD_SWITCHED = 1, // caller descheduled, other ready threads exist & ran 345 YIELD_NONEREADY = 0, // No other runnable/ready threads. 346 // platform-specific yield return immediately 347 YIELD_UNKNOWN = -1 // Unknown: platform doesn't support _SWITCHED or _NONEREADY 348 // YIELD_SWITCHED and YIELD_NONREADY imply the platform supports a "strong" 349 // yield that can be used in lieu of blocking. 350 } ; 351 static YieldResult NakedYield () ; 352 static void yield_all(int attempts = 0); // Yields to all other threads including lower priority 353 static void loop_breaker(int attempts); // called from within tight loops to possibly influence time-sharing 354 static OSReturn set_priority(Thread* thread, ThreadPriority priority); 355 static OSReturn get_priority(const Thread* const thread, ThreadPriority& priority); 356 357 static void interrupt(Thread* thread); 358 static bool is_interrupted(Thread* thread, bool clear_interrupted); 359 360 static int pd_self_suspend_thread(Thread* thread); 361 362 static ExtendedPC fetch_frame_from_context(void* ucVoid, intptr_t** sp, intptr_t** fp); 363 static frame fetch_frame_from_context(void* ucVoid); 364 365 static ExtendedPC get_thread_pc(Thread *thread); 366 static void breakpoint(); 367 368 static address current_stack_pointer(); 369 static address current_stack_base(); 370 static size_t current_stack_size(); 371 372 static int message_box(const char* title, const char* message); 373 static char* do_you_want_to_debug(const char* message); 374 375 // run cmd in a separate process and return its exit code; or -1 on failures 376 static int fork_and_exec(char *cmd); 377 378 // Set file to send error reports. 379 static void set_error_file(const char *logfile); 380 381 // os::exit() is merged with vm_exit() 382 // static void exit(int num); 383 384 // Terminate the VM, but don't exit the process 385 static void shutdown(); 386 387 // Terminate with an error. Default is to generate a core file on platforms 388 // that support such things. This calls shutdown() and then aborts. 389 static void abort(bool dump_core = true); 390 391 // Die immediately, no exit hook, no abort hook, no cleanup. 392 static void die(); 393 394 // Reading directories. 395 static DIR* opendir(const char* dirname); 396 static int readdir_buf_size(const char *path); 397 static struct dirent* readdir(DIR* dirp, dirent* dbuf); 398 static int closedir(DIR* dirp); 399 400 // Dynamic library extension 401 static const char* dll_file_extension(); 402 403 static const char* get_temp_directory(); 404 static const char* get_current_directory(char *buf, int buflen); 405 406 // Builds a platform-specific full library path given a ld path and lib name 407 static void dll_build_name(char* buffer, size_t size, 408 const char* pathname, const char* fname); 409 410 // Symbol lookup, find nearest function name; basically it implements 411 // dladdr() for all platforms. Name of the nearest function is copied 412 // to buf. Distance from its base address is returned as offset. 413 // If function name is not found, buf[0] is set to '\0' and offset is 414 // set to -1. 415 static bool dll_address_to_function_name(address addr, char* buf, 416 int buflen, int* offset); 417 418 // Locate DLL/DSO. On success, full path of the library is copied to 419 // buf, and offset is set to be the distance between addr and the 420 // library's base address. On failure, buf[0] is set to '\0' and 421 // offset is set to -1. 422 static bool dll_address_to_library_name(address addr, char* buf, 423 int buflen, int* offset); 424 425 // Find out whether the pc is in the static code for jvm.dll/libjvm.so. 426 static bool address_is_in_vm(address addr); 427 428 // Loads .dll/.so and 429 // in case of error it checks if .dll/.so was built for the 430 // same architecture as Hotspot is running on 431 static void* dll_load(const char *name, char *ebuf, int ebuflen); 432 433 // lookup symbol in a shared library 434 static void* dll_lookup(void* handle, const char* name); 435 436 // Print out system information; they are called by fatal error handler. 437 // Output format may be different on different platforms. 438 static void print_os_info(outputStream* st); 439 static void print_cpu_info(outputStream* st); 440 static void print_memory_info(outputStream* st); 441 static void print_dll_info(outputStream* st); 442 static void print_environment_variables(outputStream* st, const char** env_list, char* buffer, int len); 443 static void print_context(outputStream* st, void* context); 444 static void print_siginfo(outputStream* st, void* siginfo); 445 static void print_signal_handlers(outputStream* st, char* buf, size_t buflen); 446 static void print_date_and_time(outputStream* st); 447 448 // The following two functions are used by fatal error handler to trace 449 // native (C) frames. They are not part of frame.hpp/frame.cpp because 450 // frame.hpp/cpp assume thread is JavaThread, and also because different 451 // OS/compiler may have different convention or provide different API to 452 // walk C frames. 453 // 454 // We don't attempt to become a debugger, so we only follow frames if that 455 // does not require a lookup in the unwind table, which is part of the binary 456 // file but may be unsafe to read after a fatal error. So on x86, we can 457 // only walk stack if %ebp is used as frame pointer; on ia64, it's not 458 // possible to walk C stack without having the unwind table. 459 static bool is_first_C_frame(frame *fr); 460 static frame get_sender_for_C_frame(frame *fr); 461 462 // return current frame. pc() and sp() are set to NULL on failure. 463 static frame current_frame(); 464 465 static void print_hex_dump(outputStream* st, address start, address end, int unitsize); 466 467 // returns a string to describe the exception/signal; 468 // returns NULL if exception_code is not an OS exception/signal. 469 static const char* exception_name(int exception_code, char* buf, size_t buflen); 470 471 // Returns native Java library, loads if necessary 472 static void* native_java_library(); 473 474 // Fills in path to jvm.dll/libjvm.so (this info used to find hpi). 475 static void jvm_path(char *buf, jint buflen); 476 477 // JNI names 478 static void print_jni_name_prefix_on(outputStream* st, int args_size); 479 static void print_jni_name_suffix_on(outputStream* st, int args_size); 480 481 // File conventions 482 static const char* file_separator(); 483 static const char* line_separator(); 484 static const char* path_separator(); 485 486 // Init os specific system properties values 487 static void init_system_properties_values(); 488 489 // IO operations, non-JVM_ version. 490 static int stat(const char* path, struct stat* sbuf); 491 static bool dir_is_empty(const char* path); 492 493 // IO operations on binary files 494 static int create_binary_file(const char* path, bool rewrite_existing); 495 static jlong current_file_offset(int fd); 496 static jlong seek_to_file_offset(int fd, jlong offset); 497 498 // Thread Local Storage 499 static int allocate_thread_local_storage(); 500 static void thread_local_storage_at_put(int index, void* value); 501 static void* thread_local_storage_at(int index); 502 static void free_thread_local_storage(int index); 503 504 // General allocation (must be MT-safe) 505 static void* malloc (size_t size); 506 static void* realloc (void *memblock, size_t size); 507 static void free (void *memblock); 508 static bool check_heap(bool force = false); // verify C heap integrity 509 static char* strdup(const char *); // Like strdup 510 511#ifndef PRODUCT 512 static int num_mallocs; // # of calls to malloc/realloc 513 static size_t alloc_bytes; // # of bytes allocated 514 static int num_frees; // # of calls to free 515#endif 516 517 // Printing 64 bit integers 518 static const char* jlong_format_specifier(); 519 static const char* julong_format_specifier(); 520 521 // Support for signals (see JVM_RaiseSignal, JVM_RegisterSignal) 522 static void signal_init(); 523 static void signal_init_pd(); 524 static void signal_notify(int signal_number); 525 static void* signal(int signal_number, void* handler); 526 static void signal_raise(int signal_number); 527 static int signal_wait(); 528 static int signal_lookup(); 529 static void* user_handler(); 530 static void terminate_signal_thread(); 531 static int sigexitnum_pd(); 532 533 // random number generation 534 static long random(); // return 32bit pseudorandom number 535 static void init_random(long initval); // initialize random sequence 536 537 // Structured OS Exception support 538 static void os_exception_wrapper(java_call_t f, JavaValue* value, methodHandle* method, JavaCallArguments* args, Thread* thread); 539 540 // JVMTI & JVM monitoring and management support 541 // The thread_cpu_time() and current_thread_cpu_time() are only 542 // supported if is_thread_cpu_time_supported() returns true. 543 // They are not supported on Solaris T1. 544 545 // Thread CPU Time - return the fast estimate on a platform 546 // On Solaris - call gethrvtime (fast) - user time only 547 // On Linux - fast clock_gettime where available - user+sys 548 // - otherwise: very slow /proc fs - user+sys 549 // On Windows - GetThreadTimes - user+sys 550 static jlong current_thread_cpu_time(); 551 static jlong thread_cpu_time(Thread* t); 552 553 // Thread CPU Time with user_sys_cpu_time parameter. 554 // 555 // If user_sys_cpu_time is true, user+sys time is returned. 556 // Otherwise, only user time is returned 557 static jlong current_thread_cpu_time(bool user_sys_cpu_time); 558 static jlong thread_cpu_time(Thread* t, bool user_sys_cpu_time); 559 560 // Return a bunch of info about the timers. 561 // Note that the returned info for these two functions may be different 562 // on some platforms 563 static void current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr); 564 static void thread_cpu_time_info(jvmtiTimerInfo *info_ptr); 565 566 static bool is_thread_cpu_time_supported(); 567 568 // System loadavg support. Returns -1 if load average cannot be obtained. 569 static int loadavg(double loadavg[], int nelem); 570 571 // Hook for os specific jvm options that we don't want to abort on seeing 572 static bool obsolete_option(const JavaVMOption *option); 573 574 // Platform dependent stuff 575 #include "incls/_os_pd.hpp.incl" 576 577 // debugging support (mostly used by debug.cpp) 578 static bool find(address pc) PRODUCT_RETURN0; // OS specific function to make sense out of an address 579 580 static bool dont_yield(); // when true, JVM_Yield() is nop 581 static void print_statistics(); 582 583 // Thread priority helpers (implemented in OS-specific part) 584 static OSReturn set_native_priority(Thread* thread, int native_prio); 585 static OSReturn get_native_priority(const Thread* const thread, int* priority_ptr); 586 static int java_to_os_priority[MaxPriority + 1]; 587 // Hint to the underlying OS that a task switch would not be good. 588 // Void return because it's a hint and can fail. 589 static void hint_no_preempt(); 590 591 // Used at creation if requested by the diagnostic flag PauseAtStartup. 592 // Causes the VM to wait until an external stimulus has been applied 593 // (for Unix, that stimulus is a signal, for Windows, an external 594 // ResumeThread call) 595 static void pause(); 596 597 protected: 598 static long _rand_seed; // seed for random number generator 599 static int _processor_count; // number of processors 600 601 static char* format_boot_path(const char* format_string, 602 const char* home, 603 int home_len, 604 char fileSep, 605 char pathSep); 606 static bool set_boot_path(char fileSep, char pathSep); 607}; 608 609// Note that "PAUSE" is almost always used with synchronization 610// so arguably we should provide Atomic::SpinPause() instead 611// of the global SpinPause() with C linkage. 612// It'd also be eligible for inlining on many platforms. 613 614extern "C" int SpinPause () ; 615extern "C" int SafeFetch32 (int * adr, int errValue) ; 616extern "C" intptr_t SafeFetchN (intptr_t * adr, intptr_t errValue) ; 617