1 /* 2 * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 #ifndef SHARE_VM_RUNTIME_OS_HPP 26 #define SHARE_VM_RUNTIME_OS_HPP 27 28 #include "jvmtifiles/jvmti.h" 29 #include "runtime/atomic.hpp" 30 #include "runtime/extendedPC.hpp" 31 #include "runtime/handles.hpp" 32 #include "utilities/top.hpp" 33 #ifdef TARGET_OS_FAMILY_linux 34 # include "jvm_linux.h" 35 #endif 36 #ifdef TARGET_OS_FAMILY_solaris 37 # include "jvm_solaris.h" 38 #endif 39 #ifdef TARGET_OS_FAMILY_windows 40 # include "jvm_windows.h" 41 #endif 42 #ifdef TARGET_OS_FAMILY_bsd 43 # include "jvm_bsd.h" 44 #endif 45 46 // os defines the interface to operating system; this includes traditional 47 // OS services (time, I/O) as well as other functionality with system- 48 // dependent code. 49 50 typedef void (*dll_func)(...); 51 52 class Thread; 53 class JavaThread; 54 class Event; 55 class DLL; 56 class FileHandle; 57 template<class E> class GrowableArray; 58 59 // %%%%% Moved ThreadState, START_FN, OSThread to new osThread.hpp. -- Rose 60 61 // Platform-independent error return values from OS functions 62 enum OSReturn { 63 OS_OK = 0, // Operation was successful 64 OS_ERR = -1, // Operation failed 65 OS_INTRPT = -2, // Operation was interrupted 66 OS_TIMEOUT = -3, // Operation timed out 67 OS_NOMEM = -5, // Operation failed for lack of memory 68 OS_NORESOURCE = -6 // Operation failed for lack of nonmemory resource 69 }; 70 71 enum ThreadPriority { // JLS 20.20.1-3 72 NoPriority = -1, // Initial non-priority value 73 MinPriority = 1, // Minimum priority 74 NormPriority = 5, // Normal (non-daemon) priority 75 NearMaxPriority = 9, // High priority, used for VMThread 76 MaxPriority = 10, // Highest priority, used for WatcherThread 77 // ensures that VMThread doesn't starve profiler 78 CriticalPriority = 11 // Critical thread priority 79 }; 80 81 // Executable parameter flag for os::commit_memory() and 82 // os::commit_memory_or_exit(). 83 const bool ExecMem = true; 84 85 // Typedef for structured exception handling support 86 typedef void (*java_call_t)(JavaValue* value, methodHandle* method, JavaCallArguments* args, Thread* thread); 87 88 class os: AllStatic { 89 public: 90 enum { page_sizes_max = 9 }; // Size of _page_sizes array (8 plus a sentinel) 91 92 private: 93 static OSThread* _starting_thread; 94 static address _polling_page; 95 static volatile int32_t * _mem_serialize_page; 96 static uintptr_t _serialize_page_mask; 97 public: 98 static size_t _page_sizes[page_sizes_max]; 99 100 private: 101 static void init_page_sizes(size_t default_page_size) { 102 _page_sizes[0] = default_page_size; 103 _page_sizes[1] = 0; // sentinel 104 } 105 106 static char* pd_reserve_memory(size_t bytes, char* addr = 0, 107 size_t alignment_hint = 0); 108 static char* pd_attempt_reserve_memory_at(size_t bytes, char* addr); 109 static void pd_split_reserved_memory(char *base, size_t size, 110 size_t split, bool realloc); 111 static bool pd_commit_memory(char* addr, size_t bytes, bool executable); 112 static bool pd_commit_memory(char* addr, size_t size, size_t alignment_hint, 113 bool executable); 114 // Same as pd_commit_memory() that either succeeds or calls 115 // vm_exit_out_of_memory() with the specified mesg. 116 static void pd_commit_memory_or_exit(char* addr, size_t bytes, 117 bool executable, const char* mesg); 118 static void pd_commit_memory_or_exit(char* addr, size_t size, 119 size_t alignment_hint, 120 bool executable, const char* mesg); 121 static bool pd_uncommit_memory(char* addr, size_t bytes); 122 static bool pd_release_memory(char* addr, size_t bytes); 123 124 static char* pd_map_memory(int fd, const char* file_name, size_t file_offset, 125 char *addr, size_t bytes, bool read_only = false, 126 bool allow_exec = false); 127 static char* pd_remap_memory(int fd, const char* file_name, size_t file_offset, 128 char *addr, size_t bytes, bool read_only, 129 bool allow_exec); 130 static bool pd_unmap_memory(char *addr, size_t bytes); 131 static void pd_free_memory(char *addr, size_t bytes, size_t alignment_hint); 132 static void pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint); 133 134 135 public: 136 static void init(void); // Called before command line parsing 137 static jint init_2(void); // Called after command line parsing 138 static void init_globals(void) { // Called from init_globals() in init.cpp 139 init_globals_ext(); 140 } 141 static void init_3(void); // Called at the end of vm init 142 143 // File names are case-insensitive on windows only 144 // Override me as needed 145 static int file_name_strcmp(const char* s1, const char* s2); 146 147 static bool getenv(const char* name, char* buffer, int len); 148 static bool have_special_privileges(); 149 150 static jlong javaTimeMillis(); 151 static jlong javaTimeNanos(); 152 static void javaTimeNanos_info(jvmtiTimerInfo *info_ptr); 153 static void run_periodic_checks(); 154 155 156 // Returns the elapsed time in seconds since the vm started. 157 static double elapsedTime(); 158 159 // Returns real time in seconds since an arbitrary point 160 // in the past. 161 static bool getTimesSecs(double* process_real_time, 162 double* process_user_time, 163 double* process_system_time); 164 165 // Interface to the performance counter 166 static jlong elapsed_counter(); 167 static jlong elapsed_frequency(); 168 169 // The "virtual time" of a thread is the amount of time a thread has 170 // actually run. The first function indicates whether the OS supports 171 // this functionality for the current thread, and if so: 172 // * the second enables vtime tracking (if that is required). 173 // * the third tells whether vtime is enabled. 174 // * the fourth returns the elapsed virtual time for the current 175 // thread. 176 static bool supports_vtime(); 177 static bool enable_vtime(); 178 static bool vtime_enabled(); 179 static double elapsedVTime(); 180 181 // Return current local time in a string (YYYY-MM-DD HH:MM:SS). 182 // It is MT safe, but not async-safe, as reading time zone 183 // information may require a lock on some platforms. 184 static char* local_time_string(char *buf, size_t buflen); 185 static struct tm* localtime_pd (const time_t* clock, struct tm* res); 186 // Fill in buffer with current local time as an ISO-8601 string. 187 // E.g., YYYY-MM-DDThh:mm:ss.mmm+zzzz. 188 // Returns buffer, or NULL if it failed. 189 static char* iso8601_time(char* buffer, size_t buffer_length); 190 191 // Interface for detecting multiprocessor system 192 static inline bool is_MP() { 193 assert(_processor_count > 0, "invalid processor count"); 194 return _processor_count > 1 || AssumeMP; 195 } 196 static julong available_memory(); 197 static julong physical_memory(); 198 static bool has_allocatable_memory_limit(julong* limit); 199 static bool is_server_class_machine(); 200 201 // number of CPUs 202 static int processor_count() { 203 return _processor_count; 204 } 205 static void set_processor_count(int count) { _processor_count = count; } 206 207 // Returns the number of CPUs this process is currently allowed to run on. 208 // Note that on some OSes this can change dynamically. 209 static int active_processor_count(); 210 211 // Bind processes to processors. 212 // This is a two step procedure: 213 // first you generate a distribution of processes to processors, 214 // then you bind processes according to that distribution. 215 // Compute a distribution for number of processes to processors. 216 // Stores the processor id's into the distribution array argument. 217 // Returns true if it worked, false if it didn't. 218 static bool distribute_processes(uint length, uint* distribution); 219 // Binds the current process to a processor. 220 // Returns true if it worked, false if it didn't. 221 static bool bind_to_processor(uint processor_id); 222 223 // Give a name to the current thread. 224 static void set_native_thread_name(const char *name); 225 226 // Interface for stack banging (predetect possible stack overflow for 227 // exception processing) There are guard pages, and above that shadow 228 // pages for stack overflow checking. 229 static bool uses_stack_guard_pages(); 230 static bool allocate_stack_guard_pages(); 231 static void bang_stack_shadow_pages(); 232 static bool stack_shadow_pages_available(Thread *thread, methodHandle method); 233 234 // OS interface to Virtual Memory 235 236 // Return the default page size. 237 static int vm_page_size(); 238 239 // Return the page size to use for a region of memory. The min_pages argument 240 // is a hint intended to limit fragmentation; it says the returned page size 241 // should be <= region_max_size / min_pages. Because min_pages is a hint, 242 // this routine may return a size larger than region_max_size / min_pages. 243 // 244 // The current implementation ignores min_pages if a larger page size is an 245 // exact multiple of both region_min_size and region_max_size. This allows 246 // larger pages to be used when doing so would not cause fragmentation; in 247 // particular, a single page can be used when region_min_size == 248 // region_max_size == a supported page size. 249 static size_t page_size_for_region(size_t region_min_size, 250 size_t region_max_size, 251 uint min_pages); 252 253 // Methods for tracing page sizes returned by the above method; enabled by 254 // TracePageSizes. The region_{min,max}_size parameters should be the values 255 // passed to page_size_for_region() and page_size should be the result of that 256 // call. The (optional) base and size parameters should come from the 257 // ReservedSpace base() and size() methods. 258 static void trace_page_sizes(const char* str, const size_t* page_sizes, 259 int count) PRODUCT_RETURN; 260 static void trace_page_sizes(const char* str, const size_t region_min_size, 261 const size_t region_max_size, 262 const size_t page_size, 263 const char* base = NULL, 264 const size_t size = 0) PRODUCT_RETURN; 265 266 static int vm_allocation_granularity(); 267 static char* reserve_memory(size_t bytes, char* addr = 0, 268 size_t alignment_hint = 0); 269 static char* reserve_memory(size_t bytes, char* addr, 270 size_t alignment_hint, MEMFLAGS flags); 271 static char* reserve_memory_aligned(size_t size, size_t alignment); 272 static char* attempt_reserve_memory_at(size_t bytes, char* addr); 273 static void split_reserved_memory(char *base, size_t size, 274 size_t split, bool realloc); 275 static bool commit_memory(char* addr, size_t bytes, bool executable); 276 static bool commit_memory(char* addr, size_t size, size_t alignment_hint, 277 bool executable); 278 // Same as commit_memory() that either succeeds or calls 279 // vm_exit_out_of_memory() with the specified mesg. 280 static void commit_memory_or_exit(char* addr, size_t bytes, 281 bool executable, const char* mesg); 282 static void commit_memory_or_exit(char* addr, size_t size, 283 size_t alignment_hint, 284 bool executable, const char* mesg); 285 static bool uncommit_memory(char* addr, size_t bytes); 286 static bool release_memory(char* addr, size_t bytes); 287 288 enum ProtType { MEM_PROT_NONE, MEM_PROT_READ, MEM_PROT_RW, MEM_PROT_RWX }; 289 static bool protect_memory(char* addr, size_t bytes, ProtType prot, 290 bool is_committed = true); 291 292 static bool guard_memory(char* addr, size_t bytes); 293 static bool unguard_memory(char* addr, size_t bytes); 294 static bool create_stack_guard_pages(char* addr, size_t bytes); 295 static bool pd_create_stack_guard_pages(char* addr, size_t bytes); 296 static bool remove_stack_guard_pages(char* addr, size_t bytes); 297 298 static char* map_memory(int fd, const char* file_name, size_t file_offset, 299 char *addr, size_t bytes, bool read_only = false, 300 bool allow_exec = false); 301 static char* remap_memory(int fd, const char* file_name, size_t file_offset, 302 char *addr, size_t bytes, bool read_only, 303 bool allow_exec); 304 static bool unmap_memory(char *addr, size_t bytes); 305 static void free_memory(char *addr, size_t bytes, size_t alignment_hint); 306 static void realign_memory(char *addr, size_t bytes, size_t alignment_hint); 307 308 // NUMA-specific interface 309 static bool numa_has_static_binding(); 310 static bool numa_has_group_homing(); 311 static void numa_make_local(char *addr, size_t bytes, int lgrp_hint); 312 static void numa_make_global(char *addr, size_t bytes); 313 static size_t numa_get_groups_num(); 314 static size_t numa_get_leaf_groups(int *ids, size_t size); 315 static bool numa_topology_changed(); 316 static int numa_get_group_id(); 317 318 // Page manipulation 319 struct page_info { 320 size_t size; 321 int lgrp_id; 322 }; 323 static bool get_page_info(char *start, page_info* info); 324 static char* scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found); 325 326 static char* non_memory_address_word(); 327 // reserve, commit and pin the entire memory region 328 static char* reserve_memory_special(size_t size, char* addr = NULL, 329 bool executable = false); 330 static bool release_memory_special(char* addr, size_t bytes); 331 static void large_page_init(); 332 static size_t large_page_size(); 333 static bool can_commit_large_page_memory(); 334 static bool can_execute_large_page_memory(); 335 336 // OS interface to polling page 337 static address get_polling_page() { return _polling_page; } 338 static void set_polling_page(address page) { _polling_page = page; } 339 static bool is_poll_address(address addr) { return addr >= _polling_page && addr < (_polling_page + os::vm_page_size()); } 340 static void make_polling_page_unreadable(); 341 static void make_polling_page_readable(); 342 343 // Routines used to serialize the thread state without using membars 344 static void serialize_thread_states(); 345 346 // Since we write to the serialize page from every thread, we 347 // want stores to be on unique cache lines whenever possible 348 // in order to minimize CPU cross talk. We pre-compute the 349 // amount to shift the thread* to make this offset unique to 350 // each thread. 351 static int get_serialize_page_shift_count() { 352 return SerializePageShiftCount; 353 } 354 355 static void set_serialize_page_mask(uintptr_t mask) { 356 _serialize_page_mask = mask; 357 } 358 359 static unsigned int get_serialize_page_mask() { 360 return _serialize_page_mask; 361 } 362 363 static void set_memory_serialize_page(address page); 364 365 static address get_memory_serialize_page() { 366 return (address)_mem_serialize_page; 367 } 368 369 static inline void write_memory_serialize_page(JavaThread *thread) { 370 uintptr_t page_offset = ((uintptr_t)thread >> 371 get_serialize_page_shift_count()) & 372 get_serialize_page_mask(); 373 *(volatile int32_t *)((uintptr_t)_mem_serialize_page+page_offset) = 1; 374 } 375 376 static bool is_memory_serialize_page(JavaThread *thread, address addr) { 377 if (UseMembar) return false; 378 // Previously this function calculated the exact address of this 379 // thread's serialize page, and checked if the faulting address 380 // was equal. However, some platforms mask off faulting addresses 381 // to the page size, so now we just check that the address is 382 // within the page. This makes the thread argument unnecessary, 383 // but we retain the NULL check to preserve existing behaviour. 384 if (thread == NULL) return false; 385 address page = (address) _mem_serialize_page; 386 return addr >= page && addr < (page + os::vm_page_size()); 387 } 388 389 static void block_on_serialize_page_trap(); 390 391 // threads 392 393 enum ThreadType { 394 vm_thread, 395 cgc_thread, // Concurrent GC thread 396 pgc_thread, // Parallel GC thread 397 java_thread, 398 compiler_thread, 399 watcher_thread, 400 os_thread 401 }; 402 403 static bool create_thread(Thread* thread, 404 ThreadType thr_type, 405 size_t stack_size = 0); 406 static bool create_main_thread(JavaThread* thread); 407 static bool create_attached_thread(JavaThread* thread); 408 static void pd_start_thread(Thread* thread); 409 static void start_thread(Thread* thread); 410 411 static void initialize_thread(Thread* thr); 412 static void free_thread(OSThread* osthread); 413 414 // thread id on Linux/64bit is 64bit, on Windows and Solaris, it's 32bit 415 static intx current_thread_id(); 416 static int current_process_id(); 417 static int sleep(Thread* thread, jlong ms, bool interruptable); 418 static int naked_sleep(); 419 static void infinite_sleep(); // never returns, use with CAUTION 420 static void yield(); // Yields to all threads with same priority 421 enum YieldResult { 422 YIELD_SWITCHED = 1, // caller descheduled, other ready threads exist & ran 423 YIELD_NONEREADY = 0, // No other runnable/ready threads. 424 // platform-specific yield return immediately 425 YIELD_UNKNOWN = -1 // Unknown: platform doesn't support _SWITCHED or _NONEREADY 426 // YIELD_SWITCHED and YIELD_NONREADY imply the platform supports a "strong" 427 // yield that can be used in lieu of blocking. 428 } ; 429 static YieldResult NakedYield () ; 430 static void yield_all(int attempts = 0); // Yields to all other threads including lower priority 431 static void loop_breaker(int attempts); // called from within tight loops to possibly influence time-sharing 432 static OSReturn set_priority(Thread* thread, ThreadPriority priority); 433 static OSReturn get_priority(const Thread* const thread, ThreadPriority& priority); 434 435 static void interrupt(Thread* thread); 436 static bool is_interrupted(Thread* thread, bool clear_interrupted); 437 438 static int pd_self_suspend_thread(Thread* thread); 439 440 static ExtendedPC fetch_frame_from_context(void* ucVoid, intptr_t** sp, intptr_t** fp); 441 static frame fetch_frame_from_context(void* ucVoid); 442 443 static ExtendedPC get_thread_pc(Thread *thread); 444 static void breakpoint(); 445 446 static address current_stack_pointer(); 447 static address current_stack_base(); 448 static size_t current_stack_size(); 449 450 static void verify_stack_alignment() PRODUCT_RETURN; 451 452 static int message_box(const char* title, const char* message); 453 static char* do_you_want_to_debug(const char* message); 454 455 // run cmd in a separate process and return its exit code; or -1 on failures 456 static int fork_and_exec(char *cmd); 457 458 // Set file to send error reports. 459 static void set_error_file(const char *logfile); 460 461 // os::exit() is merged with vm_exit() 462 // static void exit(int num); 463 464 // Terminate the VM, but don't exit the process 465 static void shutdown(); 466 467 // Terminate with an error. Default is to generate a core file on platforms 468 // that support such things. This calls shutdown() and then aborts. 469 static void abort(bool dump_core = true); 470 471 // Die immediately, no exit hook, no abort hook, no cleanup. 472 static void die(); 473 474 // File i/o operations 475 static const int default_file_open_flags(); 476 static int open(const char *path, int oflag, int mode); 477 static FILE* open(int fd, const char* mode); 478 static int close(int fd); 479 static jlong lseek(int fd, jlong offset, int whence); 480 static char* native_path(char *path); 481 static int ftruncate(int fd, jlong length); 482 static int fsync(int fd); 483 static int available(int fd, jlong *bytes); 484 485 //File i/o operations 486 487 static size_t read(int fd, void *buf, unsigned int nBytes); 488 static size_t restartable_read(int fd, void *buf, unsigned int nBytes); 489 static size_t write(int fd, const void *buf, unsigned int nBytes); 490 491 // Reading directories. 492 static DIR* opendir(const char* dirname); 493 static int readdir_buf_size(const char *path); 494 static struct dirent* readdir(DIR* dirp, dirent* dbuf); 495 static int closedir(DIR* dirp); 496 497 // Dynamic library extension 498 static const char* dll_file_extension(); 499 500 static const char* get_temp_directory(); 501 static const char* get_current_directory(char *buf, size_t buflen); 502 503 // Builds a platform-specific full library path given a ld path and lib name 504 // Returns true if buffer contains full path to existing file, false otherwise 505 static bool dll_build_name(char* buffer, size_t size, 506 const char* pathname, const char* fname); 507 508 // Symbol lookup, find nearest function name; basically it implements 509 // dladdr() for all platforms. Name of the nearest function is copied 510 // to buf. Distance from its base address is returned as offset. 511 // If function name is not found, buf[0] is set to '\0' and offset is 512 // set to -1. 513 static bool dll_address_to_function_name(address addr, char* buf, 514 int buflen, int* offset); 515 516 // Locate DLL/DSO. On success, full path of the library is copied to 517 // buf, and offset is set to be the distance between addr and the 518 // library's base address. On failure, buf[0] is set to '\0' and 519 // offset is set to -1. 520 static bool dll_address_to_library_name(address addr, char* buf, 521 int buflen, int* offset); 522 523 // Find out whether the pc is in the static code for jvm.dll/libjvm.so. 524 static bool address_is_in_vm(address addr); 525 526 // Loads .dll/.so and 527 // in case of error it checks if .dll/.so was built for the 528 // same architecture as Hotspot is running on 529 static void* dll_load(const char *name, char *ebuf, int ebuflen); 530 531 // lookup symbol in a shared library 532 static void* dll_lookup(void* handle, const char* name); 533 534 // Unload library 535 static void dll_unload(void *lib); 536 537 // Print out system information; they are called by fatal error handler. 538 // Output format may be different on different platforms. 539 static void print_os_info(outputStream* st); 540 static void print_os_info_brief(outputStream* st); 541 static void print_cpu_info(outputStream* st); 542 static void pd_print_cpu_info(outputStream* st); 543 static void print_memory_info(outputStream* st); 544 static void print_dll_info(outputStream* st); 545 static void print_environment_variables(outputStream* st, const char** env_list, char* buffer, int len); 546 static void print_context(outputStream* st, void* context); 547 static void print_register_info(outputStream* st, void* context); 548 static void print_siginfo(outputStream* st, void* siginfo); 549 static void print_signal_handlers(outputStream* st, char* buf, size_t buflen); 550 static void print_date_and_time(outputStream* st); 551 552 static void print_location(outputStream* st, intptr_t x, bool verbose = false); 553 static size_t lasterror(char *buf, size_t len); 554 static int get_last_error(); 555 556 // Determines whether the calling process is being debugged by a user-mode debugger. 557 static bool is_debugger_attached(); 558 559 // wait for a key press if PauseAtExit is set 560 static void wait_for_keypress_at_exit(void); 561 562 // The following two functions are used by fatal error handler to trace 563 // native (C) frames. They are not part of frame.hpp/frame.cpp because 564 // frame.hpp/cpp assume thread is JavaThread, and also because different 565 // OS/compiler may have different convention or provide different API to 566 // walk C frames. 567 // 568 // We don't attempt to become a debugger, so we only follow frames if that 569 // does not require a lookup in the unwind table, which is part of the binary 570 // file but may be unsafe to read after a fatal error. So on x86, we can 571 // only walk stack if %ebp is used as frame pointer; on ia64, it's not 572 // possible to walk C stack without having the unwind table. 573 static bool is_first_C_frame(frame *fr); 574 static frame get_sender_for_C_frame(frame *fr); 575 576 // return current frame. pc() and sp() are set to NULL on failure. 577 static frame current_frame(); 578 579 static void print_hex_dump(outputStream* st, address start, address end, int unitsize); 580 581 // returns a string to describe the exception/signal; 582 // returns NULL if exception_code is not an OS exception/signal. 583 static const char* exception_name(int exception_code, char* buf, size_t buflen); 584 585 // Returns native Java library, loads if necessary 586 static void* native_java_library(); 587 588 // Fills in path to jvm.dll/libjvm.so (used by the Disassembler) 589 static void jvm_path(char *buf, jint buflen); 590 591 // Returns true if we are running in a headless jre. 592 static bool is_headless_jre(); 593 594 // JNI names 595 static void print_jni_name_prefix_on(outputStream* st, int args_size); 596 static void print_jni_name_suffix_on(outputStream* st, int args_size); 597 598 // File conventions 599 static const char* file_separator(); 600 static const char* line_separator(); 601 static const char* path_separator(); 602 603 // Init os specific system properties values 604 static void init_system_properties_values(); 605 606 // IO operations, non-JVM_ version. 607 static int stat(const char* path, struct stat* sbuf); 608 static bool dir_is_empty(const char* path); 609 610 // IO operations on binary files 611 static int create_binary_file(const char* path, bool rewrite_existing); 612 static jlong current_file_offset(int fd); 613 static jlong seek_to_file_offset(int fd, jlong offset); 614 615 // Thread Local Storage 616 static int allocate_thread_local_storage(); 617 static void thread_local_storage_at_put(int index, void* value); 618 static void* thread_local_storage_at(int index); 619 static void free_thread_local_storage(int index); 620 621 // Stack walk 622 static address get_caller_pc(int n = 0); 623 624 // General allocation (must be MT-safe) 625 static void* malloc (size_t size, MEMFLAGS flags, address caller_pc = 0); 626 static void* realloc (void *memblock, size_t size, MEMFLAGS flags, address caller_pc = 0); 627 static void free (void *memblock, MEMFLAGS flags = mtNone); 628 static bool check_heap(bool force = false); // verify C heap integrity 629 static char* strdup(const char *, MEMFLAGS flags = mtInternal); // Like strdup 630 631 #ifndef PRODUCT 632 static julong num_mallocs; // # of calls to malloc/realloc 633 static julong alloc_bytes; // # of bytes allocated 634 static julong num_frees; // # of calls to free 635 static julong free_bytes; // # of bytes freed 636 #endif 637 638 // SocketInterface (ex HPI SocketInterface ) 639 static int socket(int domain, int type, int protocol); 640 static int socket_close(int fd); 641 static int socket_shutdown(int fd, int howto); 642 static int recv(int fd, char* buf, size_t nBytes, uint flags); 643 static int send(int fd, char* buf, size_t nBytes, uint flags); 644 static int raw_send(int fd, char* buf, size_t nBytes, uint flags); 645 static int timeout(int fd, long timeout); 646 static int listen(int fd, int count); 647 static int connect(int fd, struct sockaddr* him, socklen_t len); 648 static int bind(int fd, struct sockaddr* him, socklen_t len); 649 static int accept(int fd, struct sockaddr* him, socklen_t* len); 650 static int recvfrom(int fd, char* buf, size_t nbytes, uint flags, 651 struct sockaddr* from, socklen_t* fromlen); 652 static int get_sock_name(int fd, struct sockaddr* him, socklen_t* len); 653 static int sendto(int fd, char* buf, size_t len, uint flags, 654 struct sockaddr* to, socklen_t tolen); 655 static int socket_available(int fd, jint* pbytes); 656 657 static int get_sock_opt(int fd, int level, int optname, 658 char* optval, socklen_t* optlen); 659 static int set_sock_opt(int fd, int level, int optname, 660 const char* optval, socklen_t optlen); 661 static int get_host_name(char* name, int namelen); 662 663 static struct hostent* get_host_by_name(char* name); 664 665 // Support for signals (see JVM_RaiseSignal, JVM_RegisterSignal) 666 static void signal_init(); 667 static void signal_init_pd(); 668 static void signal_notify(int signal_number); 669 static void* signal(int signal_number, void* handler); 670 static void signal_raise(int signal_number); 671 static int signal_wait(); 672 static int signal_lookup(); 673 static void* user_handler(); 674 static void terminate_signal_thread(); 675 static int sigexitnum_pd(); 676 677 // random number generation 678 static long random(); // return 32bit pseudorandom number 679 static void init_random(long initval); // initialize random sequence 680 681 // Structured OS Exception support 682 static void os_exception_wrapper(java_call_t f, JavaValue* value, methodHandle* method, JavaCallArguments* args, Thread* thread); 683 684 // On Windows this will create an actual minidump, on Linux/Solaris it will simply check core dump limits 685 static void check_or_create_dump(void* exceptionRecord, void* contextRecord, char* buffer, size_t bufferSize); 686 687 // Get the default path to the core file 688 // Returns the length of the string 689 static int get_core_path(char* buffer, size_t bufferSize); 690 691 // JVMTI & JVM monitoring and management support 692 // The thread_cpu_time() and current_thread_cpu_time() are only 693 // supported if is_thread_cpu_time_supported() returns true. 694 // They are not supported on Solaris T1. 695 696 // Thread CPU Time - return the fast estimate on a platform 697 // On Solaris - call gethrvtime (fast) - user time only 698 // On Linux - fast clock_gettime where available - user+sys 699 // - otherwise: very slow /proc fs - user+sys 700 // On Windows - GetThreadTimes - user+sys 701 static jlong current_thread_cpu_time(); 702 static jlong thread_cpu_time(Thread* t); 703 704 // Thread CPU Time with user_sys_cpu_time parameter. 705 // 706 // If user_sys_cpu_time is true, user+sys time is returned. 707 // Otherwise, only user time is returned 708 static jlong current_thread_cpu_time(bool user_sys_cpu_time); 709 static jlong thread_cpu_time(Thread* t, bool user_sys_cpu_time); 710 711 // Return a bunch of info about the timers. 712 // Note that the returned info for these two functions may be different 713 // on some platforms 714 static void current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr); 715 static void thread_cpu_time_info(jvmtiTimerInfo *info_ptr); 716 717 static bool is_thread_cpu_time_supported(); 718 719 // System loadavg support. Returns -1 if load average cannot be obtained. 720 static int loadavg(double loadavg[], int nelem); 721 722 // Hook for os specific jvm options that we don't want to abort on seeing 723 static bool obsolete_option(const JavaVMOption *option); 724 725 // Read file line by line. If line is longer than bsize, 726 // rest of line is skipped. Returns number of bytes read or -1 on EOF 727 static int get_line_chars(int fd, char *buf, const size_t bsize); 728 729 // Extensions 730 #include "runtime/os_ext.hpp" 731 732 public: 733 734 // Platform dependent stuff 735 #ifdef TARGET_OS_FAMILY_linux 736 # include "os_linux.hpp" 737 # include "os_posix.hpp" 738 #endif 739 #ifdef TARGET_OS_FAMILY_solaris 740 # include "os_solaris.hpp" 741 # include "os_posix.hpp" 742 #endif 743 #ifdef TARGET_OS_FAMILY_windows 744 # include "os_windows.hpp" 745 #endif 746 #ifdef TARGET_OS_FAMILY_bsd 747 # include "os_posix.hpp" 748 # include "os_bsd.hpp" 749 #endif 750 #ifdef TARGET_OS_ARCH_linux_x86 751 # include "os_linux_x86.hpp" 752 #endif 753 #ifdef TARGET_OS_ARCH_linux_sparc 754 # include "os_linux_sparc.hpp" 755 #endif 756 #ifdef TARGET_OS_ARCH_linux_zero 757 # include "os_linux_zero.hpp" 758 #endif 759 #ifdef TARGET_OS_ARCH_solaris_x86 760 # include "os_solaris_x86.hpp" 761 #endif 762 #ifdef TARGET_OS_ARCH_solaris_sparc 763 # include "os_solaris_sparc.hpp" 764 #endif 765 #ifdef TARGET_OS_ARCH_windows_x86 766 # include "os_windows_x86.hpp" 767 #endif 768 #ifdef TARGET_OS_ARCH_linux_arm 769 # include "os_linux_arm.hpp" 770 #endif 771 #ifdef TARGET_OS_ARCH_linux_ppc 772 # include "os_linux_ppc.hpp" 773 #endif 774 #ifdef TARGET_OS_ARCH_bsd_x86 775 # include "os_bsd_x86.hpp" 776 #endif 777 #ifdef TARGET_OS_ARCH_bsd_zero 778 # include "os_bsd_zero.hpp" 779 #endif 780 781 public: 782 // debugging support (mostly used by debug.cpp but also fatal error handler) 783 static bool find(address pc, outputStream* st = tty); // OS specific function to make sense out of an address 784 785 static bool dont_yield(); // when true, JVM_Yield() is nop 786 static void print_statistics(); 787 788 // Thread priority helpers (implemented in OS-specific part) 789 static OSReturn set_native_priority(Thread* thread, int native_prio); 790 static OSReturn get_native_priority(const Thread* const thread, int* priority_ptr); 791 static int java_to_os_priority[CriticalPriority + 1]; 792 // Hint to the underlying OS that a task switch would not be good. 793 // Void return because it's a hint and can fail. 794 static void hint_no_preempt(); 795 796 // Used at creation if requested by the diagnostic flag PauseAtStartup. 797 // Causes the VM to wait until an external stimulus has been applied 798 // (for Unix, that stimulus is a signal, for Windows, an external 799 // ResumeThread call) 800 static void pause(); 801 802 class SuspendedThreadTaskContext { 803 public: 804 SuspendedThreadTaskContext(Thread* thread, void *ucontext) : _thread(thread), _ucontext(ucontext) {} 805 Thread* thread() const { return _thread; } 806 void* ucontext() const { return _ucontext; } 807 private: 808 Thread* _thread; 809 void* _ucontext; 810 }; 811 812 class SuspendedThreadTask { 813 public: 814 SuspendedThreadTask(Thread* thread) : _thread(thread), _done(false) {} 815 virtual ~SuspendedThreadTask() {} 816 void run(); 817 bool is_done() { return _done; } 818 virtual void do_task(const SuspendedThreadTaskContext& context) = 0; 819 protected: 820 private: 821 void internal_do_task(); 822 Thread* _thread; 823 bool _done; 824 }; 825 826 #ifndef TARGET_OS_FAMILY_windows 827 // Suspend/resume support 828 // Protocol: 829 // 830 // a thread starts in SR_RUNNING 831 // 832 // SR_RUNNING can go to 833 // * SR_SUSPEND_REQUEST when the WatcherThread wants to suspend it 834 // SR_SUSPEND_REQUEST can go to 835 // * SR_RUNNING if WatcherThread decides it waited for SR_SUSPENDED too long (timeout) 836 // * SR_SUSPENDED if the stopped thread receives the signal and switches state 837 // SR_SUSPENDED can go to 838 // * SR_WAKEUP_REQUEST when the WatcherThread has done the work and wants to resume 839 // SR_WAKEUP_REQUEST can go to 840 // * SR_RUNNING when the stopped thread receives the signal 841 // * SR_WAKEUP_REQUEST on timeout (resend the signal and try again) 842 class SuspendResume { 843 public: 844 enum State { 845 SR_RUNNING, 846 SR_SUSPEND_REQUEST, 847 SR_SUSPENDED, 848 SR_WAKEUP_REQUEST 849 }; 850 851 private: 852 volatile State _state; 853 854 private: 855 /* try to switch state from state "from" to state "to" 856 * returns the state set after the method is complete 857 */ 858 State switch_state(State from, State to); 859 860 public: 861 SuspendResume() : _state(SR_RUNNING) { } 862 863 State state() const { return _state; } 864 865 State request_suspend() { 866 return switch_state(SR_RUNNING, SR_SUSPEND_REQUEST); 867 } 868 869 State cancel_suspend() { 870 return switch_state(SR_SUSPEND_REQUEST, SR_RUNNING); 871 } 872 873 State suspended() { 874 return switch_state(SR_SUSPEND_REQUEST, SR_SUSPENDED); 875 } 876 877 State request_wakeup() { 878 return switch_state(SR_SUSPENDED, SR_WAKEUP_REQUEST); 879 } 880 881 State running() { 882 return switch_state(SR_WAKEUP_REQUEST, SR_RUNNING); 883 } 884 885 bool is_running() const { 886 return _state == SR_RUNNING; 887 } 888 889 bool is_suspend_request() const { 890 return _state == SR_SUSPEND_REQUEST; 891 } 892 893 bool is_suspended() const { 894 return _state == SR_SUSPENDED; 895 } 896 }; 897 #endif 898 899 900 protected: 901 static long _rand_seed; // seed for random number generator 902 static int _processor_count; // number of processors 903 904 static char* format_boot_path(const char* format_string, 905 const char* home, 906 int home_len, 907 char fileSep, 908 char pathSep); 909 static bool set_boot_path(char fileSep, char pathSep); 910 static char** split_path(const char* path, int* n); 911 }; 912 913 // Note that "PAUSE" is almost always used with synchronization 914 // so arguably we should provide Atomic::SpinPause() instead 915 // of the global SpinPause() with C linkage. 916 // It'd also be eligible for inlining on many platforms. 917 918 extern "C" int SpinPause () ; 919 extern "C" int SafeFetch32 (int * adr, int errValue) ; 920 extern "C" intptr_t SafeFetchN (intptr_t * adr, intptr_t errValue) ; 921 922 #endif // SHARE_VM_RUNTIME_OS_HPP