1 /* 2 * Copyright (c) 1997, 2014, 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 # include <setjmp.h> 36 #endif 37 #ifdef TARGET_OS_FAMILY_solaris 38 # include "jvm_solaris.h" 39 # include <setjmp.h> 40 #endif 41 #ifdef TARGET_OS_FAMILY_windows 42 # include "jvm_windows.h" 43 #endif 44 #ifdef TARGET_OS_FAMILY_aix 45 # include "jvm_aix.h" 46 # include <setjmp.h> 47 #endif 48 #ifdef TARGET_OS_FAMILY_bsd 49 # include "jvm_bsd.h" 50 # include <setjmp.h> 51 #endif 52 53 class AgentLibrary; 54 55 // os defines the interface to operating system; this includes traditional 56 // OS services (time, I/O) as well as other functionality with system- 57 // dependent code. 58 59 typedef void (*dll_func)(...); 60 61 class Thread; 62 class JavaThread; 63 class Event; 64 class DLL; 65 class FileHandle; 66 template<class E> class GrowableArray; 67 68 // %%%%% Moved ThreadState, START_FN, OSThread to new osThread.hpp. -- Rose 69 70 // Platform-independent error return values from OS functions 71 enum OSReturn { 72 OS_OK = 0, // Operation was successful 73 OS_ERR = -1, // Operation failed 74 OS_INTRPT = -2, // Operation was interrupted 75 OS_TIMEOUT = -3, // Operation timed out 76 OS_NOMEM = -5, // Operation failed for lack of memory 77 OS_NORESOURCE = -6 // Operation failed for lack of nonmemory resource 78 }; 79 80 enum ThreadPriority { // JLS 20.20.1-3 81 NoPriority = -1, // Initial non-priority value 82 MinPriority = 1, // Minimum priority 83 NormPriority = 5, // Normal (non-daemon) priority 84 NearMaxPriority = 9, // High priority, used for VMThread 85 MaxPriority = 10, // Highest priority, used for WatcherThread 86 // ensures that VMThread doesn't starve profiler 87 CriticalPriority = 11 // Critical thread priority 88 }; 89 90 // Executable parameter flag for os::commit_memory() and 91 // os::commit_memory_or_exit(). 92 const bool ExecMem = true; 93 94 // Typedef for structured exception handling support 95 typedef void (*java_call_t)(JavaValue* value, methodHandle* method, JavaCallArguments* args, Thread* thread); 96 97 class os: AllStatic { 98 friend class VMStructs; 99 100 public: 101 enum { page_sizes_max = 9 }; // Size of _page_sizes array (8 plus a sentinel) 102 103 private: 104 static OSThread* _starting_thread; 105 static address _polling_page; 106 static volatile int32_t * _mem_serialize_page; 107 static uintptr_t _serialize_page_mask; 108 public: 109 static size_t _page_sizes[page_sizes_max]; 110 111 private: 112 static void init_page_sizes(size_t default_page_size) { 113 _page_sizes[0] = default_page_size; 114 _page_sizes[1] = 0; // sentinel 115 } 116 117 static char* pd_reserve_memory(size_t bytes, char* addr = 0, 118 size_t alignment_hint = 0); 119 static char* pd_attempt_reserve_memory_at(size_t bytes, char* addr); 120 static void pd_split_reserved_memory(char *base, size_t size, 121 size_t split, bool realloc); 122 static bool pd_commit_memory(char* addr, size_t bytes, bool executable); 123 static bool pd_commit_memory(char* addr, size_t size, size_t alignment_hint, 124 bool executable); 125 // Same as pd_commit_memory() that either succeeds or calls 126 // vm_exit_out_of_memory() with the specified mesg. 127 static void pd_commit_memory_or_exit(char* addr, size_t bytes, 128 bool executable, const char* mesg); 129 static void pd_commit_memory_or_exit(char* addr, size_t size, 130 size_t alignment_hint, 131 bool executable, const char* mesg); 132 static bool pd_uncommit_memory(char* addr, size_t bytes); 133 static bool pd_release_memory(char* addr, size_t bytes); 134 135 static char* pd_map_memory(int fd, const char* file_name, size_t file_offset, 136 char *addr, size_t bytes, bool read_only = false, 137 bool allow_exec = false); 138 static char* pd_remap_memory(int fd, const char* file_name, size_t file_offset, 139 char *addr, size_t bytes, bool read_only, 140 bool allow_exec); 141 static bool pd_unmap_memory(char *addr, size_t bytes); 142 static void pd_free_memory(char *addr, size_t bytes, size_t alignment_hint); 143 static void pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint); 144 145 146 public: 147 static void init(void); // Called before command line parsing 148 static void init_before_ergo(void); // Called after command line parsing 149 // before VM ergonomics processing. 150 static jint init_2(void); // Called after command line parsing 151 // and VM ergonomics processing 152 static void init_globals(void) { // Called from init_globals() in init.cpp 153 init_globals_ext(); 154 } 155 static void init_3(void); // Called at the end of vm init 156 157 // File names are case-insensitive on windows only 158 // Override me as needed 159 static int file_name_strcmp(const char* s1, const char* s2); 160 161 static bool getenv(const char* name, char* buffer, int len); 162 static bool have_special_privileges(); 163 164 static jlong javaTimeMillis(); 165 static jlong javaTimeNanos(); 166 static void javaTimeNanos_info(jvmtiTimerInfo *info_ptr); 167 static void run_periodic_checks(); 168 static bool supports_monotonic_clock(); 169 170 171 // Returns the elapsed time in seconds since the vm started. 172 static double elapsedTime(); 173 174 // Returns real time in seconds since an arbitrary point 175 // in the past. 176 static bool getTimesSecs(double* process_real_time, 177 double* process_user_time, 178 double* process_system_time); 179 180 // Interface to the performance counter 181 static jlong elapsed_counter(); 182 static jlong elapsed_frequency(); 183 184 // The "virtual time" of a thread is the amount of time a thread has 185 // actually run. The first function indicates whether the OS supports 186 // this functionality for the current thread, and if so: 187 // * the second enables vtime tracking (if that is required). 188 // * the third tells whether vtime is enabled. 189 // * the fourth returns the elapsed virtual time for the current 190 // thread. 191 static bool supports_vtime(); 192 static bool enable_vtime(); 193 static bool vtime_enabled(); 194 static double elapsedVTime(); 195 196 // Return current local time in a string (YYYY-MM-DD HH:MM:SS). 197 // It is MT safe, but not async-safe, as reading time zone 198 // information may require a lock on some platforms. 199 static char* local_time_string(char *buf, size_t buflen); 200 static struct tm* localtime_pd (const time_t* clock, struct tm* res); 201 // Fill in buffer with current local time as an ISO-8601 string. 202 // E.g., YYYY-MM-DDThh:mm:ss.mmm+zzzz. 203 // Returns buffer, or NULL if it failed. 204 static char* iso8601_time(char* buffer, size_t buffer_length); 205 206 // Interface for detecting multiprocessor system 207 static inline bool is_MP() { 208 assert(_processor_count > 0, "invalid processor count"); 209 return _processor_count > 1 || AssumeMP; 210 } 211 static julong available_memory(); 212 static julong physical_memory(); 213 static bool has_allocatable_memory_limit(julong* limit); 214 static bool is_server_class_machine(); 215 216 // number of CPUs 217 static int processor_count() { 218 return _processor_count; 219 } 220 static void set_processor_count(int count) { _processor_count = count; } 221 222 // Returns the number of CPUs this process is currently allowed to run on. 223 // Note that on some OSes this can change dynamically. 224 static int active_processor_count(); 225 226 // Bind processes to processors. 227 // This is a two step procedure: 228 // first you generate a distribution of processes to processors, 229 // then you bind processes according to that distribution. 230 // Compute a distribution for number of processes to processors. 231 // Stores the processor id's into the distribution array argument. 232 // Returns true if it worked, false if it didn't. 233 static bool distribute_processes(uint length, uint* distribution); 234 // Binds the current process to a processor. 235 // Returns true if it worked, false if it didn't. 236 static bool bind_to_processor(uint processor_id); 237 238 // Give a name to the current thread. 239 static void set_native_thread_name(const char *name); 240 241 // Interface for stack banging (predetect possible stack overflow for 242 // exception processing) There are guard pages, and above that shadow 243 // pages for stack overflow checking. 244 static bool uses_stack_guard_pages(); 245 static bool allocate_stack_guard_pages(); 246 static void bang_stack_shadow_pages(); 247 static bool stack_shadow_pages_available(Thread *thread, methodHandle method); 248 249 // OS interface to Virtual Memory 250 251 // Return the default page size. 252 static int vm_page_size(); 253 254 // Return the page size to use for a region of memory. The min_pages argument 255 // is a hint intended to limit fragmentation; it says the returned page size 256 // should be <= region_max_size / min_pages. Because min_pages is a hint, 257 // this routine may return a size larger than region_max_size / min_pages. 258 // 259 // The current implementation ignores min_pages if a larger page size is an 260 // exact multiple of both region_min_size and region_max_size. This allows 261 // larger pages to be used when doing so would not cause fragmentation; in 262 // particular, a single page can be used when region_min_size == 263 // region_max_size == a supported page size. 264 static size_t page_size_for_region(size_t region_min_size, 265 size_t region_max_size, 266 uint min_pages); 267 // Return the largest page size that can be used 268 static size_t max_page_size() { 269 // The _page_sizes array is sorted in descending order. 270 return _page_sizes[0]; 271 } 272 273 // Methods for tracing page sizes returned by the above method; enabled by 274 // TracePageSizes. The region_{min,max}_size parameters should be the values 275 // passed to page_size_for_region() and page_size should be the result of that 276 // call. The (optional) base and size parameters should come from the 277 // ReservedSpace base() and size() methods. 278 static void trace_page_sizes(const char* str, const size_t* page_sizes, 279 int count) PRODUCT_RETURN; 280 static void trace_page_sizes(const char* str, const size_t region_min_size, 281 const size_t region_max_size, 282 const size_t page_size, 283 const char* base = NULL, 284 const size_t size = 0) PRODUCT_RETURN; 285 286 static int vm_allocation_granularity(); 287 static char* reserve_memory(size_t bytes, char* addr = 0, 288 size_t alignment_hint = 0); 289 static char* reserve_memory(size_t bytes, char* addr, 290 size_t alignment_hint, MEMFLAGS flags); 291 static char* reserve_memory_aligned(size_t size, size_t alignment); 292 static char* attempt_reserve_memory_at(size_t bytes, char* addr); 293 static void split_reserved_memory(char *base, size_t size, 294 size_t split, bool realloc); 295 static bool commit_memory(char* addr, size_t bytes, bool executable); 296 static bool commit_memory(char* addr, size_t size, size_t alignment_hint, 297 bool executable); 298 // Same as commit_memory() that either succeeds or calls 299 // vm_exit_out_of_memory() with the specified mesg. 300 static void commit_memory_or_exit(char* addr, size_t bytes, 301 bool executable, const char* mesg); 302 static void commit_memory_or_exit(char* addr, size_t size, 303 size_t alignment_hint, 304 bool executable, const char* mesg); 305 static bool uncommit_memory(char* addr, size_t bytes); 306 static bool release_memory(char* addr, size_t bytes); 307 308 enum ProtType { MEM_PROT_NONE, MEM_PROT_READ, MEM_PROT_RW, MEM_PROT_RWX }; 309 static bool protect_memory(char* addr, size_t bytes, ProtType prot, 310 bool is_committed = true); 311 312 static bool guard_memory(char* addr, size_t bytes); 313 static bool unguard_memory(char* addr, size_t bytes); 314 static bool create_stack_guard_pages(char* addr, size_t bytes); 315 static bool pd_create_stack_guard_pages(char* addr, size_t bytes); 316 static bool remove_stack_guard_pages(char* addr, size_t bytes); 317 318 static char* map_memory(int fd, const char* file_name, size_t file_offset, 319 char *addr, size_t bytes, bool read_only = false, 320 bool allow_exec = false); 321 static char* remap_memory(int fd, const char* file_name, size_t file_offset, 322 char *addr, size_t bytes, bool read_only, 323 bool allow_exec); 324 static bool unmap_memory(char *addr, size_t bytes); 325 static void free_memory(char *addr, size_t bytes, size_t alignment_hint); 326 static void realign_memory(char *addr, size_t bytes, size_t alignment_hint); 327 328 // NUMA-specific interface 329 static bool numa_has_static_binding(); 330 static bool numa_has_group_homing(); 331 static void numa_make_local(char *addr, size_t bytes, int lgrp_hint); 332 static void numa_make_global(char *addr, size_t bytes); 333 static size_t numa_get_groups_num(); 334 static size_t numa_get_leaf_groups(int *ids, size_t size); 335 static bool numa_topology_changed(); 336 static int numa_get_group_id(); 337 338 // Page manipulation 339 struct page_info { 340 size_t size; 341 int lgrp_id; 342 }; 343 static bool get_page_info(char *start, page_info* info); 344 static char* scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found); 345 346 static char* non_memory_address_word(); 347 // reserve, commit and pin the entire memory region 348 static char* reserve_memory_special(size_t size, size_t alignment, 349 char* addr, bool executable); 350 static bool release_memory_special(char* addr, size_t bytes); 351 static void large_page_init(); 352 static size_t large_page_size(); 353 static bool can_commit_large_page_memory(); 354 static bool can_execute_large_page_memory(); 355 356 // OS interface to polling page 357 static address get_polling_page() { return _polling_page; } 358 static void set_polling_page(address page) { _polling_page = page; } 359 static bool is_poll_address(address addr) { return addr >= _polling_page && addr < (_polling_page + os::vm_page_size()); } 360 static void make_polling_page_unreadable(); 361 static void make_polling_page_readable(); 362 363 // Routines used to serialize the thread state without using membars 364 static void serialize_thread_states(); 365 366 // Since we write to the serialize page from every thread, we 367 // want stores to be on unique cache lines whenever possible 368 // in order to minimize CPU cross talk. We pre-compute the 369 // amount to shift the thread* to make this offset unique to 370 // each thread. 371 static int get_serialize_page_shift_count() { 372 return SerializePageShiftCount; 373 } 374 375 static void set_serialize_page_mask(uintptr_t mask) { 376 _serialize_page_mask = mask; 377 } 378 379 static unsigned int get_serialize_page_mask() { 380 return _serialize_page_mask; 381 } 382 383 static void set_memory_serialize_page(address page); 384 385 static address get_memory_serialize_page() { 386 return (address)_mem_serialize_page; 387 } 388 389 static inline void write_memory_serialize_page(JavaThread *thread) { 390 uintptr_t page_offset = ((uintptr_t)thread >> 391 get_serialize_page_shift_count()) & 392 get_serialize_page_mask(); 393 *(volatile int32_t *)((uintptr_t)_mem_serialize_page+page_offset) = 1; 394 } 395 396 static bool is_memory_serialize_page(JavaThread *thread, address addr) { 397 if (UseMembar) return false; 398 // Previously this function calculated the exact address of this 399 // thread's serialize page, and checked if the faulting address 400 // was equal. However, some platforms mask off faulting addresses 401 // to the page size, so now we just check that the address is 402 // within the page. This makes the thread argument unnecessary, 403 // but we retain the NULL check to preserve existing behavior. 404 if (thread == NULL) return false; 405 address page = (address) _mem_serialize_page; 406 return addr >= page && addr < (page + os::vm_page_size()); 407 } 408 409 static void block_on_serialize_page_trap(); 410 411 // threads 412 413 enum ThreadType { 414 vm_thread, 415 cgc_thread, // Concurrent GC thread 416 pgc_thread, // Parallel GC thread 417 java_thread, 418 compiler_thread, 419 watcher_thread, 420 os_thread 421 }; 422 423 static bool create_thread(Thread* thread, 424 ThreadType thr_type, 425 size_t stack_size = 0); 426 static bool create_main_thread(JavaThread* thread); 427 static bool create_attached_thread(JavaThread* thread); 428 static void pd_start_thread(Thread* thread); 429 static void start_thread(Thread* thread); 430 431 static void initialize_thread(Thread* thr); 432 static void free_thread(OSThread* osthread); 433 434 // thread id on Linux/64bit is 64bit, on Windows and Solaris, it's 32bit 435 static intx current_thread_id(); 436 static int current_process_id(); 437 static int sleep(Thread* thread, jlong ms, bool interruptable); 438 // Short standalone OS sleep suitable for slow path spin loop. 439 // Ignores Thread.interrupt() (so keep it short). 440 // ms = 0, will sleep for the least amount of time allowed by the OS. 441 static void naked_short_sleep(jlong ms); 442 static void infinite_sleep(); // never returns, use with CAUTION 443 static void yield(); // Yields to all threads with same priority 444 enum YieldResult { 445 YIELD_SWITCHED = 1, // caller descheduled, other ready threads exist & ran 446 YIELD_NONEREADY = 0, // No other runnable/ready threads. 447 // platform-specific yield return immediately 448 YIELD_UNKNOWN = -1 // Unknown: platform doesn't support _SWITCHED or _NONEREADY 449 // YIELD_SWITCHED and YIELD_NONREADY imply the platform supports a "strong" 450 // yield that can be used in lieu of blocking. 451 } ; 452 static YieldResult NakedYield () ; 453 static void yield_all(); // Yields to all other threads including lower priority 454 // (for the default scheduling policy) 455 static OSReturn set_priority(Thread* thread, ThreadPriority priority); 456 static OSReturn get_priority(const Thread* const thread, ThreadPriority& priority); 457 458 static void interrupt(Thread* thread); 459 static bool is_interrupted(Thread* thread, bool clear_interrupted); 460 461 static int pd_self_suspend_thread(Thread* thread); 462 463 static ExtendedPC fetch_frame_from_context(void* ucVoid, intptr_t** sp, intptr_t** fp); 464 static frame fetch_frame_from_context(void* ucVoid); 465 466 static ExtendedPC get_thread_pc(Thread *thread); 467 static void breakpoint(); 468 469 static address current_stack_pointer(); 470 static address current_stack_base(); 471 static size_t current_stack_size(); 472 473 static void verify_stack_alignment() PRODUCT_RETURN; 474 475 static int message_box(const char* title, const char* message); 476 static char* do_you_want_to_debug(const char* message); 477 478 // run cmd in a separate process and return its exit code; or -1 on failures 479 static int fork_and_exec(char *cmd); 480 481 // Set file to send error reports. 482 static void set_error_file(const char *logfile); 483 484 // os::exit() is merged with vm_exit() 485 // static void exit(int num); 486 487 // Terminate the VM, but don't exit the process 488 static void shutdown(); 489 490 // Terminate with an error. Default is to generate a core file on platforms 491 // that support such things. This calls shutdown() and then aborts. 492 static void abort(bool dump_core = true); 493 494 // Die immediately, no exit hook, no abort hook, no cleanup. 495 static void die(); 496 497 // File i/o operations 498 static const int default_file_open_flags(); 499 static int open(const char *path, int oflag, int mode); 500 static FILE* open(int fd, const char* mode); 501 static int close(int fd); 502 static jlong lseek(int fd, jlong offset, int whence); 503 static char* native_path(char *path); 504 static int ftruncate(int fd, jlong length); 505 static int fsync(int fd); 506 static int available(int fd, jlong *bytes); 507 508 //File i/o operations 509 510 static size_t read(int fd, void *buf, unsigned int nBytes); 511 static size_t restartable_read(int fd, void *buf, unsigned int nBytes); 512 static size_t write(int fd, const void *buf, unsigned int nBytes); 513 514 // Reading directories. 515 static DIR* opendir(const char* dirname); 516 static int readdir_buf_size(const char *path); 517 static struct dirent* readdir(DIR* dirp, dirent* dbuf); 518 static int closedir(DIR* dirp); 519 520 // Dynamic library extension 521 static const char* dll_file_extension(); 522 523 static const char* get_temp_directory(); 524 static const char* get_current_directory(char *buf, size_t buflen); 525 526 // Builds a platform-specific full library path given a ld path and lib name 527 // Returns true if buffer contains full path to existing file, false otherwise 528 static bool dll_build_name(char* buffer, size_t size, 529 const char* pathname, const char* fname); 530 531 // Symbol lookup, find nearest function name; basically it implements 532 // dladdr() for all platforms. Name of the nearest function is copied 533 // to buf. Distance from its base address is optionally returned as offset. 534 // If function name is not found, buf[0] is set to '\0' and offset is 535 // set to -1 (if offset is non-NULL). 536 static bool dll_address_to_function_name(address addr, char* buf, 537 int buflen, int* offset); 538 539 // Locate DLL/DSO. On success, full path of the library is copied to 540 // buf, and offset is optionally set to be the distance between addr 541 // and the library's base address. On failure, buf[0] is set to '\0' 542 // and offset is set to -1 (if offset is non-NULL). 543 static bool dll_address_to_library_name(address addr, char* buf, 544 int buflen, int* offset); 545 546 // Find out whether the pc is in the static code for jvm.dll/libjvm.so. 547 static bool address_is_in_vm(address addr); 548 549 // Loads .dll/.so and 550 // in case of error it checks if .dll/.so was built for the 551 // same architecture as HotSpot is running on 552 static void* dll_load(const char *name, char *ebuf, int ebuflen); 553 554 // lookup symbol in a shared library 555 static void* dll_lookup(void* handle, const char* name); 556 557 // Unload library 558 static void dll_unload(void *lib); 559 560 // Return the handle of this process 561 static void* get_default_process_handle(); 562 563 // Check for static linked agent library 564 static bool find_builtin_agent(AgentLibrary *agent_lib, const char *syms[], 565 size_t syms_len); 566 567 // Find agent entry point 568 static void *find_agent_function(AgentLibrary *agent_lib, bool check_lib, 569 const char *syms[], size_t syms_len); 570 571 // Print out system information; they are called by fatal error handler. 572 // Output format may be different on different platforms. 573 static void print_os_info(outputStream* st); 574 static void print_os_info_brief(outputStream* st); 575 static void print_cpu_info(outputStream* st); 576 static void pd_print_cpu_info(outputStream* st); 577 static void print_memory_info(outputStream* st); 578 static void print_dll_info(outputStream* st); 579 static void print_environment_variables(outputStream* st, const char** env_list, char* buffer, int len); 580 static void print_context(outputStream* st, void* context); 581 static void print_register_info(outputStream* st, void* context); 582 static void print_siginfo(outputStream* st, void* siginfo); 583 static void print_signal_handlers(outputStream* st, char* buf, size_t buflen); 584 static void print_date_and_time(outputStream* st); 585 586 static void print_location(outputStream* st, intptr_t x, bool verbose = false); 587 static size_t lasterror(char *buf, size_t len); 588 static int get_last_error(); 589 590 // Determines whether the calling process is being debugged by a user-mode debugger. 591 static bool is_debugger_attached(); 592 593 // wait for a key press if PauseAtExit is set 594 static void wait_for_keypress_at_exit(void); 595 596 // The following two functions are used by fatal error handler to trace 597 // native (C) frames. They are not part of frame.hpp/frame.cpp because 598 // frame.hpp/cpp assume thread is JavaThread, and also because different 599 // OS/compiler may have different convention or provide different API to 600 // walk C frames. 601 // 602 // We don't attempt to become a debugger, so we only follow frames if that 603 // does not require a lookup in the unwind table, which is part of the binary 604 // file but may be unsafe to read after a fatal error. So on x86, we can 605 // only walk stack if %ebp is used as frame pointer; on ia64, it's not 606 // possible to walk C stack without having the unwind table. 607 static bool is_first_C_frame(frame *fr); 608 static frame get_sender_for_C_frame(frame *fr); 609 610 // return current frame. pc() and sp() are set to NULL on failure. 611 static frame current_frame(); 612 613 static void print_hex_dump(outputStream* st, address start, address end, int unitsize); 614 615 // returns a string to describe the exception/signal; 616 // returns NULL if exception_code is not an OS exception/signal. 617 static const char* exception_name(int exception_code, char* buf, size_t buflen); 618 619 // Returns native Java library, loads if necessary 620 static void* native_java_library(); 621 622 // Fills in path to jvm.dll/libjvm.so (used by the Disassembler) 623 static void jvm_path(char *buf, jint buflen); 624 625 // Returns true if we are running in a headless jre. 626 static bool is_headless_jre(); 627 628 // JNI names 629 static void print_jni_name_prefix_on(outputStream* st, int args_size); 630 static void print_jni_name_suffix_on(outputStream* st, int args_size); 631 632 // File conventions 633 static const char* file_separator(); 634 static const char* line_separator(); 635 static const char* path_separator(); 636 637 // Init os specific system properties values 638 static void init_system_properties_values(); 639 640 // IO operations, non-JVM_ version. 641 static int stat(const char* path, struct stat* sbuf); 642 static bool dir_is_empty(const char* path); 643 644 // IO operations on binary files 645 static int create_binary_file(const char* path, bool rewrite_existing); 646 static jlong current_file_offset(int fd); 647 static jlong seek_to_file_offset(int fd, jlong offset); 648 649 // Thread Local Storage 650 static int allocate_thread_local_storage(); 651 static void thread_local_storage_at_put(int index, void* value); 652 static void* thread_local_storage_at(int index); 653 static void free_thread_local_storage(int index); 654 655 // Stack walk 656 static address get_caller_pc(int n = 0); 657 658 // General allocation (must be MT-safe) 659 static void* malloc (size_t size, MEMFLAGS flags, address caller_pc = 0); 660 static void* realloc (void *memblock, size_t size, MEMFLAGS flags, address caller_pc = 0); 661 static void free (void *memblock, MEMFLAGS flags = mtNone); 662 static bool check_heap(bool force = false); // verify C heap integrity 663 static char* strdup(const char *, MEMFLAGS flags = mtInternal); // Like strdup 664 665 #ifndef PRODUCT 666 static julong num_mallocs; // # of calls to malloc/realloc 667 static julong alloc_bytes; // # of bytes allocated 668 static julong num_frees; // # of calls to free 669 static julong free_bytes; // # of bytes freed 670 #endif 671 672 // SocketInterface (ex HPI SocketInterface ) 673 static int socket(int domain, int type, int protocol); 674 static int socket_close(int fd); 675 static int socket_shutdown(int fd, int howto); 676 static int recv(int fd, char* buf, size_t nBytes, uint flags); 677 static int send(int fd, char* buf, size_t nBytes, uint flags); 678 static int raw_send(int fd, char* buf, size_t nBytes, uint flags); 679 static int timeout(int fd, long timeout); 680 static int listen(int fd, int count); 681 static int connect(int fd, struct sockaddr* him, socklen_t len); 682 static int bind(int fd, struct sockaddr* him, socklen_t len); 683 static int accept(int fd, struct sockaddr* him, socklen_t* len); 684 static int recvfrom(int fd, char* buf, size_t nbytes, uint flags, 685 struct sockaddr* from, socklen_t* fromlen); 686 static int get_sock_name(int fd, struct sockaddr* him, socklen_t* len); 687 static int sendto(int fd, char* buf, size_t len, uint flags, 688 struct sockaddr* to, socklen_t tolen); 689 static int socket_available(int fd, jint* pbytes); 690 691 static int get_sock_opt(int fd, int level, int optname, 692 char* optval, socklen_t* optlen); 693 static int set_sock_opt(int fd, int level, int optname, 694 const char* optval, socklen_t optlen); 695 static int get_host_name(char* name, int namelen); 696 697 static struct hostent* get_host_by_name(char* name); 698 699 // Support for signals (see JVM_RaiseSignal, JVM_RegisterSignal) 700 static void signal_init(); 701 static void signal_init_pd(); 702 static void signal_notify(int signal_number); 703 static void* signal(int signal_number, void* handler); 704 static void signal_raise(int signal_number); 705 static int signal_wait(); 706 static int signal_lookup(); 707 static void* user_handler(); 708 static void terminate_signal_thread(); 709 static int sigexitnum_pd(); 710 711 // random number generation 712 static long random(); // return 32bit pseudorandom number 713 static void init_random(long initval); // initialize random sequence 714 715 // Structured OS Exception support 716 static void os_exception_wrapper(java_call_t f, JavaValue* value, methodHandle* method, JavaCallArguments* args, Thread* thread); 717 718 // On Windows this will create an actual minidump, on Linux/Solaris it will simply check core dump limits 719 static void check_or_create_dump(void* exceptionRecord, void* contextRecord, char* buffer, size_t bufferSize); 720 721 // Get the default path to the core file 722 // Returns the length of the string 723 static int get_core_path(char* buffer, size_t bufferSize); 724 725 // JVMTI & JVM monitoring and management support 726 // The thread_cpu_time() and current_thread_cpu_time() are only 727 // supported if is_thread_cpu_time_supported() returns true. 728 // They are not supported on Solaris T1. 729 730 // Thread CPU Time - return the fast estimate on a platform 731 // On Solaris - call gethrvtime (fast) - user time only 732 // On Linux - fast clock_gettime where available - user+sys 733 // - otherwise: very slow /proc fs - user+sys 734 // On Windows - GetThreadTimes - user+sys 735 static jlong current_thread_cpu_time(); 736 static jlong thread_cpu_time(Thread* t); 737 738 // Thread CPU Time with user_sys_cpu_time parameter. 739 // 740 // If user_sys_cpu_time is true, user+sys time is returned. 741 // Otherwise, only user time is returned 742 static jlong current_thread_cpu_time(bool user_sys_cpu_time); 743 static jlong thread_cpu_time(Thread* t, bool user_sys_cpu_time); 744 745 // Return a bunch of info about the timers. 746 // Note that the returned info for these two functions may be different 747 // on some platforms 748 static void current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr); 749 static void thread_cpu_time_info(jvmtiTimerInfo *info_ptr); 750 751 static bool is_thread_cpu_time_supported(); 752 753 // System loadavg support. Returns -1 if load average cannot be obtained. 754 static int loadavg(double loadavg[], int nelem); 755 756 // Hook for os specific jvm options that we don't want to abort on seeing 757 static bool obsolete_option(const JavaVMOption *option); 758 759 // Extensions 760 #include "runtime/os_ext.hpp" 761 762 public: 763 class CrashProtectionCallback : public StackObj { 764 public: 765 virtual void call() = 0; 766 }; 767 768 // Platform dependent stuff 769 #ifdef TARGET_OS_FAMILY_linux 770 # include "os_linux.hpp" 771 # include "os_posix.hpp" 772 #endif 773 #ifdef TARGET_OS_FAMILY_solaris 774 # include "os_solaris.hpp" 775 # include "os_posix.hpp" 776 #endif 777 #ifdef TARGET_OS_FAMILY_windows 778 # include "os_windows.hpp" 779 #endif 780 #ifdef TARGET_OS_FAMILY_aix 781 # include "os_aix.hpp" 782 # include "os_posix.hpp" 783 #endif 784 #ifdef TARGET_OS_FAMILY_bsd 785 # include "os_posix.hpp" 786 # include "os_bsd.hpp" 787 #endif 788 #ifdef TARGET_OS_ARCH_linux_x86 789 # include "os_linux_x86.hpp" 790 #endif 791 #ifdef TARGET_OS_ARCH_linux_sparc 792 # include "os_linux_sparc.hpp" 793 #endif 794 #ifdef TARGET_OS_ARCH_linux_zero 795 # include "os_linux_zero.hpp" 796 #endif 797 #ifdef TARGET_OS_ARCH_solaris_x86 798 # include "os_solaris_x86.hpp" 799 #endif 800 #ifdef TARGET_OS_ARCH_solaris_sparc 801 # include "os_solaris_sparc.hpp" 802 #endif 803 #ifdef TARGET_OS_ARCH_windows_x86 804 # include "os_windows_x86.hpp" 805 #endif 806 #ifdef TARGET_OS_ARCH_linux_arm 807 # include "os_linux_arm.hpp" 808 #endif 809 #ifdef TARGET_OS_ARCH_linux_ppc 810 # include "os_linux_ppc.hpp" 811 #endif 812 #ifdef TARGET_OS_ARCH_aix_ppc 813 # include "os_aix_ppc.hpp" 814 #endif 815 #ifdef TARGET_OS_ARCH_bsd_x86 816 # include "os_bsd_x86.hpp" 817 #endif 818 #ifdef TARGET_OS_ARCH_bsd_zero 819 # include "os_bsd_zero.hpp" 820 #endif 821 822 #ifndef OS_NATIVE_THREAD_CREATION_FAILED_MSG 823 #define OS_NATIVE_THREAD_CREATION_FAILED_MSG "unable to create native thread: possibly out of memory or process/resource limits reached" 824 #endif 825 826 public: 827 #ifndef PLATFORM_PRINT_NATIVE_STACK 828 // No platform-specific code for printing the native stack. 829 static bool platform_print_native_stack(outputStream* st, void* context, 830 char *buf, int buf_size) { 831 return false; 832 } 833 #endif 834 835 // debugging support (mostly used by debug.cpp but also fatal error handler) 836 static bool find(address pc, outputStream* st = tty); // OS specific function to make sense out of an address 837 838 static bool dont_yield(); // when true, JVM_Yield() is nop 839 static void print_statistics(); 840 841 // Thread priority helpers (implemented in OS-specific part) 842 static OSReturn set_native_priority(Thread* thread, int native_prio); 843 static OSReturn get_native_priority(const Thread* const thread, int* priority_ptr); 844 static int java_to_os_priority[CriticalPriority + 1]; 845 // Hint to the underlying OS that a task switch would not be good. 846 // Void return because it's a hint and can fail. 847 static void hint_no_preempt(); 848 static const char* native_thread_creation_failed_msg() { 849 return OS_NATIVE_THREAD_CREATION_FAILED_MSG; 850 } 851 852 // Used at creation if requested by the diagnostic flag PauseAtStartup. 853 // Causes the VM to wait until an external stimulus has been applied 854 // (for Unix, that stimulus is a signal, for Windows, an external 855 // ResumeThread call) 856 static void pause(); 857 858 // Builds a platform dependent Agent_OnLoad_<libname> function name 859 // which is used to find statically linked in agents. 860 static char* build_agent_function_name(const char *sym, const char *cname, 861 bool is_absolute_path); 862 863 class SuspendedThreadTaskContext { 864 public: 865 SuspendedThreadTaskContext(Thread* thread, void *ucontext) : _thread(thread), _ucontext(ucontext) {} 866 Thread* thread() const { return _thread; } 867 void* ucontext() const { return _ucontext; } 868 private: 869 Thread* _thread; 870 void* _ucontext; 871 }; 872 873 class SuspendedThreadTask { 874 public: 875 SuspendedThreadTask(Thread* thread) : _thread(thread), _done(false) {} 876 virtual ~SuspendedThreadTask() {} 877 void run(); 878 bool is_done() { return _done; } 879 virtual void do_task(const SuspendedThreadTaskContext& context) = 0; 880 protected: 881 private: 882 void internal_do_task(); 883 Thread* _thread; 884 bool _done; 885 }; 886 887 #ifndef TARGET_OS_FAMILY_windows 888 // Suspend/resume support 889 // Protocol: 890 // 891 // a thread starts in SR_RUNNING 892 // 893 // SR_RUNNING can go to 894 // * SR_SUSPEND_REQUEST when the WatcherThread wants to suspend it 895 // SR_SUSPEND_REQUEST can go to 896 // * SR_RUNNING if WatcherThread decides it waited for SR_SUSPENDED too long (timeout) 897 // * SR_SUSPENDED if the stopped thread receives the signal and switches state 898 // SR_SUSPENDED can go to 899 // * SR_WAKEUP_REQUEST when the WatcherThread has done the work and wants to resume 900 // SR_WAKEUP_REQUEST can go to 901 // * SR_RUNNING when the stopped thread receives the signal 902 // * SR_WAKEUP_REQUEST on timeout (resend the signal and try again) 903 class SuspendResume { 904 public: 905 enum State { 906 SR_RUNNING, 907 SR_SUSPEND_REQUEST, 908 SR_SUSPENDED, 909 SR_WAKEUP_REQUEST 910 }; 911 912 private: 913 volatile State _state; 914 915 private: 916 /* try to switch state from state "from" to state "to" 917 * returns the state set after the method is complete 918 */ 919 State switch_state(State from, State to); 920 921 public: 922 SuspendResume() : _state(SR_RUNNING) { } 923 924 State state() const { return _state; } 925 926 State request_suspend() { 927 return switch_state(SR_RUNNING, SR_SUSPEND_REQUEST); 928 } 929 930 State cancel_suspend() { 931 return switch_state(SR_SUSPEND_REQUEST, SR_RUNNING); 932 } 933 934 State suspended() { 935 return switch_state(SR_SUSPEND_REQUEST, SR_SUSPENDED); 936 } 937 938 State request_wakeup() { 939 return switch_state(SR_SUSPENDED, SR_WAKEUP_REQUEST); 940 } 941 942 State running() { 943 return switch_state(SR_WAKEUP_REQUEST, SR_RUNNING); 944 } 945 946 bool is_running() const { 947 return _state == SR_RUNNING; 948 } 949 950 bool is_suspend_request() const { 951 return _state == SR_SUSPEND_REQUEST; 952 } 953 954 bool is_suspended() const { 955 return _state == SR_SUSPENDED; 956 } 957 }; 958 #endif 959 960 961 protected: 962 static long _rand_seed; // seed for random number generator 963 static int _processor_count; // number of processors 964 965 static char* format_boot_path(const char* format_string, 966 const char* home, 967 int home_len, 968 char fileSep, 969 char pathSep); 970 static bool set_boot_path(char fileSep, char pathSep); 971 static char** split_path(const char* path, int* n); 972 973 }; 974 975 // Note that "PAUSE" is almost always used with synchronization 976 // so arguably we should provide Atomic::SpinPause() instead 977 // of the global SpinPause() with C linkage. 978 // It'd also be eligible for inlining on many platforms. 979 980 extern "C" int SpinPause(); 981 982 #endif // SHARE_VM_RUNTIME_OS_HPP