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