1 /* 2 * Copyright (c) 1997, 2015, 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/extendedPC.hpp" 30 #include "runtime/handles.hpp" 31 #include "utilities/semaphore.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 # ifdef __APPLE__ 52 # include <mach/mach_time.h> 53 # endif 54 #endif 55 56 class AgentLibrary; 57 58 // os defines the interface to operating system; this includes traditional 59 // OS services (time, I/O) as well as other functionality with system- 60 // dependent code. 61 62 typedef void (*dll_func)(...); 63 64 class Thread; 65 class JavaThread; 66 class Event; 67 class DLL; 68 class FileHandle; 69 class NativeCallStack; 70 71 template<class E> class GrowableArray; 72 73 // %%%%% Moved ThreadState, START_FN, OSThread to new osThread.hpp. -- Rose 74 75 // Platform-independent error return values from OS functions 76 enum OSReturn { 77 OS_OK = 0, // Operation was successful 78 OS_ERR = -1, // Operation failed 79 OS_INTRPT = -2, // Operation was interrupted 80 OS_TIMEOUT = -3, // Operation timed out 81 OS_NOMEM = -5, // Operation failed for lack of memory 82 OS_NORESOURCE = -6 // Operation failed for lack of nonmemory resource 83 }; 84 85 enum ThreadPriority { // JLS 20.20.1-3 86 NoPriority = -1, // Initial non-priority value 87 MinPriority = 1, // Minimum priority 88 NormPriority = 5, // Normal (non-daemon) priority 89 NearMaxPriority = 9, // High priority, used for VMThread 90 MaxPriority = 10, // Highest priority, used for WatcherThread 91 // ensures that VMThread doesn't starve profiler 92 CriticalPriority = 11 // Critical thread priority 93 }; 94 95 // Executable parameter flag for os::commit_memory() and 96 // os::commit_memory_or_exit(). 97 const bool ExecMem = true; 98 99 // Typedef for structured exception handling support 100 typedef void (*java_call_t)(JavaValue* value, methodHandle* method, JavaCallArguments* args, Thread* thread); 101 102 class MallocTracker; 103 104 class os: AllStatic { 105 friend class VMStructs; 106 friend class MallocTracker; 107 public: 108 enum { page_sizes_max = 9 }; // Size of _page_sizes array (8 plus a sentinel) 109 110 private: 111 static OSThread* _starting_thread; 112 static address _polling_page; 113 static volatile int32_t * _mem_serialize_page; 114 static uintptr_t _serialize_page_mask; 115 public: 116 static size_t _page_sizes[page_sizes_max]; 117 118 private: 119 static void init_page_sizes(size_t default_page_size) { 120 _page_sizes[0] = default_page_size; 121 _page_sizes[1] = 0; // sentinel 122 } 123 124 static char* pd_reserve_memory(size_t bytes, char* addr = 0, 125 size_t alignment_hint = 0); 126 static char* pd_attempt_reserve_memory_at(size_t bytes, char* addr); 127 static void pd_split_reserved_memory(char *base, size_t size, 128 size_t split, bool realloc); 129 static bool pd_commit_memory(char* addr, size_t bytes, bool executable); 130 static bool pd_commit_memory(char* addr, size_t size, size_t alignment_hint, 131 bool executable); 132 // Same as pd_commit_memory() that either succeeds or calls 133 // vm_exit_out_of_memory() with the specified mesg. 134 static void pd_commit_memory_or_exit(char* addr, size_t bytes, 135 bool executable, const char* mesg); 136 static void pd_commit_memory_or_exit(char* addr, size_t size, 137 size_t alignment_hint, 138 bool executable, const char* mesg); 139 static bool pd_uncommit_memory(char* addr, size_t bytes); 140 static bool pd_release_memory(char* addr, size_t bytes); 141 142 static char* pd_map_memory(int fd, const char* file_name, size_t file_offset, 143 char *addr, size_t bytes, bool read_only = false, 144 bool allow_exec = false); 145 static char* pd_remap_memory(int fd, const char* file_name, size_t file_offset, 146 char *addr, size_t bytes, bool read_only, 147 bool allow_exec); 148 static bool pd_unmap_memory(char *addr, size_t bytes); 149 static void pd_free_memory(char *addr, size_t bytes, size_t alignment_hint); 150 static void pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint); 151 152 static size_t page_size_for_region(size_t region_size, size_t min_pages, bool must_be_aligned); 153 154 public: 155 static void init(void); // Called before command line parsing 156 static void init_before_ergo(void); // Called after command line parsing 157 // before VM ergonomics processing. 158 static jint init_2(void); // Called after command line parsing 159 // and VM ergonomics processing 160 static void init_globals(void) { // Called from init_globals() in init.cpp 161 init_globals_ext(); 162 } 163 164 // File names are case-insensitive on windows only 165 // Override me as needed 166 static int file_name_strcmp(const char* s1, const char* s2); 167 168 // unset environment variable 169 static bool unsetenv(const char* name); 170 171 static bool have_special_privileges(); 172 173 static jlong javaTimeMillis(); 174 static jlong javaTimeNanos(); 175 static void javaTimeNanos_info(jvmtiTimerInfo *info_ptr); 176 static void javaTimeSystemUTC(jlong &seconds, jlong &nanos); 177 static void run_periodic_checks(); 178 static bool supports_monotonic_clock(); 179 180 // Returns the elapsed time in seconds since the vm started. 181 static double elapsedTime(); 182 183 // Returns real time in seconds since an arbitrary point 184 // in the past. 185 static bool getTimesSecs(double* process_real_time, 186 double* process_user_time, 187 double* process_system_time); 188 189 // Interface to the performance counter 190 static jlong elapsed_counter(); 191 static jlong elapsed_frequency(); 192 193 // The "virtual time" of a thread is the amount of time a thread has 194 // actually run. The first function indicates whether the OS supports 195 // this functionality for the current thread, and if so: 196 // * the second enables vtime tracking (if that is required). 197 // * the third tells whether vtime is enabled. 198 // * the fourth returns the elapsed virtual time for the current 199 // thread. 200 static bool supports_vtime(); 201 static bool enable_vtime(); 202 static bool vtime_enabled(); 203 static double elapsedVTime(); 204 205 // Return current local time in a string (YYYY-MM-DD HH:MM:SS). 206 // It is MT safe, but not async-safe, as reading time zone 207 // information may require a lock on some platforms. 208 static char* local_time_string(char *buf, size_t buflen); 209 static struct tm* localtime_pd (const time_t* clock, struct tm* res); 210 // Fill in buffer with current local time as an ISO-8601 string. 211 // E.g., YYYY-MM-DDThh:mm:ss.mmm+zzzz. 212 // Returns buffer, or NULL if it failed. 213 static char* iso8601_time(char* buffer, size_t buffer_length); 214 215 // Interface for detecting multiprocessor system 216 static inline bool is_MP() { 217 // During bootstrap if _processor_count is not yet initialized 218 // we claim to be MP as that is safest. If any platform has a 219 // stub generator that might be triggered in this phase and for 220 // which being declared MP when in fact not, is a problem - then 221 // the bootstrap routine for the stub generator needs to check 222 // the processor count directly and leave the bootstrap routine 223 // in place until called after initialization has ocurred. 224 return (_processor_count != 1) || AssumeMP; 225 } 226 static julong available_memory(); 227 static julong physical_memory(); 228 static bool has_allocatable_memory_limit(julong* limit); 229 static bool is_server_class_machine(); 230 231 // number of CPUs 232 static int processor_count() { 233 return _processor_count; 234 } 235 static void set_processor_count(int count) { _processor_count = count; } 236 237 // Returns the number of CPUs this process is currently allowed to run on. 238 // Note that on some OSes this can change dynamically. 239 static int active_processor_count(); 240 241 // Bind processes to processors. 242 // This is a two step procedure: 243 // first you generate a distribution of processes to processors, 244 // then you bind processes according to that distribution. 245 // Compute a distribution for number of processes to processors. 246 // Stores the processor id's into the distribution array argument. 247 // Returns true if it worked, false if it didn't. 248 static bool distribute_processes(uint length, uint* distribution); 249 // Binds the current process to a processor. 250 // Returns true if it worked, false if it didn't. 251 static bool bind_to_processor(uint processor_id); 252 253 // Give a name to the current thread. 254 static void set_native_thread_name(const char *name); 255 256 // Interface for stack banging (predetect possible stack overflow for 257 // exception processing) There are guard pages, and above that shadow 258 // pages for stack overflow checking. 259 static bool uses_stack_guard_pages(); 260 static bool allocate_stack_guard_pages(); 261 static void bang_stack_shadow_pages(); 262 static bool stack_shadow_pages_available(Thread *thread, methodHandle method); 263 264 // OS interface to Virtual Memory 265 266 // Return the default page size. 267 static int vm_page_size(); 268 269 // Returns the page size to use for a region of memory. 270 // region_size / min_pages will always be greater than or equal to the 271 // returned value. The returned value will divide region_size. 272 static size_t page_size_for_region_aligned(size_t region_size, size_t min_pages); 273 274 // Returns the page size to use for a region of memory. 275 // region_size / min_pages will always be greater than or equal to the 276 // returned value. The returned value might not divide region_size. 277 static size_t page_size_for_region_unaligned(size_t region_size, size_t min_pages); 278 279 // Return the largest page size that can be used 280 static size_t max_page_size() { 281 // The _page_sizes array is sorted in descending order. 282 return _page_sizes[0]; 283 } 284 285 // Methods for tracing page sizes returned by the above method; enabled by 286 // TracePageSizes. The region_{min,max}_size parameters should be the values 287 // passed to page_size_for_region() and page_size should be the result of that 288 // call. The (optional) base and size parameters should come from the 289 // ReservedSpace base() and size() methods. 290 static void trace_page_sizes(const char* str, const size_t* page_sizes, 291 int count) PRODUCT_RETURN; 292 static void trace_page_sizes(const char* str, const size_t region_min_size, 293 const size_t region_max_size, 294 const size_t page_size, 295 const char* base = NULL, 296 const size_t size = 0) PRODUCT_RETURN; 297 298 static int vm_allocation_granularity(); 299 static char* reserve_memory(size_t bytes, char* addr = 0, 300 size_t alignment_hint = 0); 301 static char* reserve_memory(size_t bytes, char* addr, 302 size_t alignment_hint, MEMFLAGS flags); 303 static char* reserve_memory_aligned(size_t size, size_t alignment); 304 static char* attempt_reserve_memory_at(size_t bytes, char* addr); 305 static void split_reserved_memory(char *base, size_t size, 306 size_t split, bool realloc); 307 static bool commit_memory(char* addr, size_t bytes, bool executable); 308 static bool commit_memory(char* addr, size_t size, size_t alignment_hint, 309 bool executable); 310 // Same as commit_memory() that either succeeds or calls 311 // vm_exit_out_of_memory() with the specified mesg. 312 static void commit_memory_or_exit(char* addr, size_t bytes, 313 bool executable, const char* mesg); 314 static void commit_memory_or_exit(char* addr, size_t size, 315 size_t alignment_hint, 316 bool executable, const char* mesg); 317 static bool uncommit_memory(char* addr, size_t bytes); 318 static bool release_memory(char* addr, size_t bytes); 319 320 // Touch memory pages that cover the memory range from start to end (exclusive) 321 // to make the OS back the memory range with actual memory. 322 // Current implementation may not touch the last page if unaligned addresses 323 // are passed. 324 static void pretouch_memory(char* start, char* end); 325 326 enum ProtType { MEM_PROT_NONE, MEM_PROT_READ, MEM_PROT_RW, MEM_PROT_RWX }; 327 static bool protect_memory(char* addr, size_t bytes, ProtType prot, 328 bool is_committed = true); 329 330 static bool guard_memory(char* addr, size_t bytes); 331 static bool unguard_memory(char* addr, size_t bytes); 332 static bool create_stack_guard_pages(char* addr, size_t bytes); 333 static bool pd_create_stack_guard_pages(char* addr, size_t bytes); 334 static bool remove_stack_guard_pages(char* addr, size_t bytes); 335 336 static char* map_memory(int fd, const char* file_name, size_t file_offset, 337 char *addr, size_t bytes, bool read_only = false, 338 bool allow_exec = false); 339 static char* remap_memory(int fd, const char* file_name, size_t file_offset, 340 char *addr, size_t bytes, bool read_only, 341 bool allow_exec); 342 static bool unmap_memory(char *addr, size_t bytes); 343 static void free_memory(char *addr, size_t bytes, size_t alignment_hint); 344 static void realign_memory(char *addr, size_t bytes, size_t alignment_hint); 345 346 // NUMA-specific interface 347 static bool numa_has_static_binding(); 348 static bool numa_has_group_homing(); 349 static void numa_make_local(char *addr, size_t bytes, int lgrp_hint); 350 static void numa_make_global(char *addr, size_t bytes); 351 static size_t numa_get_groups_num(); 352 static size_t numa_get_leaf_groups(int *ids, size_t size); 353 static bool numa_topology_changed(); 354 static int numa_get_group_id(); 355 356 // Page manipulation 357 struct page_info { 358 size_t size; 359 int lgrp_id; 360 }; 361 static bool get_page_info(char *start, page_info* info); 362 static char* scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found); 363 364 static char* non_memory_address_word(); 365 // reserve, commit and pin the entire memory region 366 static char* reserve_memory_special(size_t size, size_t alignment, 367 char* addr, bool executable); 368 static bool release_memory_special(char* addr, size_t bytes); 369 static void large_page_init(); 370 static size_t large_page_size(); 371 static bool can_commit_large_page_memory(); 372 static bool can_execute_large_page_memory(); 373 374 // OS interface to polling page 375 static address get_polling_page() { return _polling_page; } 376 static void set_polling_page(address page) { _polling_page = page; } 377 static bool is_poll_address(address addr) { return addr >= _polling_page && addr < (_polling_page + os::vm_page_size()); } 378 static void make_polling_page_unreadable(); 379 static void make_polling_page_readable(); 380 381 // Routines used to serialize the thread state without using membars 382 static void serialize_thread_states(); 383 384 // Since we write to the serialize page from every thread, we 385 // want stores to be on unique cache lines whenever possible 386 // in order to minimize CPU cross talk. We pre-compute the 387 // amount to shift the thread* to make this offset unique to 388 // each thread. 389 static int get_serialize_page_shift_count() { 390 return SerializePageShiftCount; 391 } 392 393 static void set_serialize_page_mask(uintptr_t mask) { 394 _serialize_page_mask = mask; 395 } 396 397 static unsigned int get_serialize_page_mask() { 398 return _serialize_page_mask; 399 } 400 401 static void set_memory_serialize_page(address page); 402 403 static address get_memory_serialize_page() { 404 return (address)_mem_serialize_page; 405 } 406 407 static inline void write_memory_serialize_page(JavaThread *thread) { 408 uintptr_t page_offset = ((uintptr_t)thread >> 409 get_serialize_page_shift_count()) & 410 get_serialize_page_mask(); 411 *(volatile int32_t *)((uintptr_t)_mem_serialize_page+page_offset) = 1; 412 } 413 414 static bool is_memory_serialize_page(JavaThread *thread, address addr) { 415 if (UseMembar) return false; 416 // Previously this function calculated the exact address of this 417 // thread's serialize page, and checked if the faulting address 418 // was equal. However, some platforms mask off faulting addresses 419 // to the page size, so now we just check that the address is 420 // within the page. This makes the thread argument unnecessary, 421 // but we retain the NULL check to preserve existing behavior. 422 if (thread == NULL) return false; 423 address page = (address) _mem_serialize_page; 424 return addr >= page && addr < (page + os::vm_page_size()); 425 } 426 427 static void block_on_serialize_page_trap(); 428 429 // threads 430 431 enum ThreadType { 432 vm_thread, 433 cgc_thread, // Concurrent GC thread 434 pgc_thread, // Parallel GC thread 435 java_thread, 436 compiler_thread, 437 watcher_thread, 438 os_thread 439 }; 440 441 static bool create_thread(Thread* thread, 442 ThreadType thr_type, 443 size_t stack_size = 0); 444 static bool create_main_thread(JavaThread* thread); 445 static bool create_attached_thread(JavaThread* thread); 446 static void pd_start_thread(Thread* thread); 447 static void start_thread(Thread* thread); 448 449 static void initialize_thread(Thread* thr); 450 static void free_thread(OSThread* osthread); 451 452 // thread id on Linux/64bit is 64bit, on Windows and Solaris, it's 32bit 453 static intx current_thread_id(); 454 static int current_process_id(); 455 static int sleep(Thread* thread, jlong ms, bool interruptable); 456 // Short standalone OS sleep suitable for slow path spin loop. 457 // Ignores Thread.interrupt() (so keep it short). 458 // ms = 0, will sleep for the least amount of time allowed by the OS. 459 static void naked_short_sleep(jlong ms); 460 static void infinite_sleep(); // never returns, use with CAUTION 461 static void naked_yield () ; 462 static OSReturn set_priority(Thread* thread, ThreadPriority priority); 463 static OSReturn get_priority(const Thread* const thread, ThreadPriority& priority); 464 465 static void interrupt(Thread* thread); 466 static bool is_interrupted(Thread* thread, bool clear_interrupted); 467 468 static int pd_self_suspend_thread(Thread* thread); 469 470 static ExtendedPC fetch_frame_from_context(void* ucVoid, intptr_t** sp, intptr_t** fp); 471 static frame fetch_frame_from_context(void* ucVoid); 472 473 static ExtendedPC get_thread_pc(Thread *thread); 474 static void breakpoint(); 475 476 static address current_stack_pointer(); 477 static address current_stack_base(); 478 static size_t current_stack_size(); 479 480 static void verify_stack_alignment() PRODUCT_RETURN; 481 482 static int message_box(const char* title, const char* message); 483 static char* do_you_want_to_debug(const char* message); 484 485 // run cmd in a separate process and return its exit code; or -1 on failures 486 static int fork_and_exec(char *cmd); 487 488 // Call ::exit() on all platforms but Windows 489 static void exit(int num); 490 491 // Terminate the VM, but don't exit the process 492 static void shutdown(); 493 494 // Terminate with an error. Default is to generate a core file on platforms 495 // that support such things. This calls shutdown() and then aborts. 496 static void abort(bool dump_core, void *siginfo, void *context); 497 static void abort(bool dump_core = true); 498 499 // Die immediately, no exit hook, no abort hook, no cleanup. 500 static void die(); 501 502 // File i/o operations 503 static const int default_file_open_flags(); 504 static int open(const char *path, int oflag, int mode); 505 static FILE* open(int fd, const char* mode); 506 static int close(int fd); 507 static jlong lseek(int fd, jlong offset, int whence); 508 static char* native_path(char *path); 509 static int ftruncate(int fd, jlong length); 510 static int fsync(int fd); 511 static int available(int fd, jlong *bytes); 512 513 //File i/o operations 514 515 static size_t read(int fd, void *buf, unsigned int nBytes); 516 static size_t read_at(int fd, void *buf, unsigned int nBytes, jlong offset); 517 static size_t restartable_read(int fd, void *buf, unsigned int nBytes); 518 static size_t write(int fd, const void *buf, unsigned int nBytes); 519 520 // Reading directories. 521 static DIR* opendir(const char* dirname); 522 static int readdir_buf_size(const char *path); 523 static struct dirent* readdir(DIR* dirp, dirent* dbuf); 524 static int closedir(DIR* dirp); 525 526 // Dynamic library extension 527 static const char* dll_file_extension(); 528 529 static const char* get_temp_directory(); 530 static const char* get_current_directory(char *buf, size_t buflen); 531 532 // Builds a platform-specific full library path given a ld path and lib name 533 // Returns true if buffer contains full path to existing file, false otherwise 534 static bool dll_build_name(char* buffer, size_t size, 535 const char* pathname, const char* fname); 536 537 // Symbol lookup, find nearest function name; basically it implements 538 // dladdr() for all platforms. Name of the nearest function is copied 539 // to buf. Distance from its base address is optionally returned as offset. 540 // If function name is not found, buf[0] is set to '\0' and offset is 541 // set to -1 (if offset is non-NULL). 542 static bool dll_address_to_function_name(address addr, char* buf, 543 int buflen, int* offset); 544 545 // Locate DLL/DSO. On success, full path of the library is copied to 546 // buf, and offset is optionally set to be the distance between addr 547 // and the library's base address. On failure, buf[0] is set to '\0' 548 // and offset is set to -1 (if offset is non-NULL). 549 static bool dll_address_to_library_name(address addr, char* buf, 550 int buflen, int* offset); 551 552 // Find out whether the pc is in the static code for jvm.dll/libjvm.so. 553 static bool address_is_in_vm(address addr); 554 555 // Loads .dll/.so and 556 // in case of error it checks if .dll/.so was built for the 557 // same architecture as HotSpot is running on 558 static void* dll_load(const char *name, char *ebuf, int ebuflen); 559 560 // lookup symbol in a shared library 561 static void* dll_lookup(void* handle, const char* name); 562 563 // Unload library 564 static void dll_unload(void *lib); 565 566 // Callback for loaded module information 567 // Input parameters: 568 // char* module_file_name, 569 // address module_base_addr, 570 // address module_top_addr, 571 // void* param 572 typedef int (*LoadedModulesCallbackFunc)(const char *, address, address, void *); 573 574 static int get_loaded_modules_info(LoadedModulesCallbackFunc callback, void *param); 575 576 // Return the handle of this process 577 static void* get_default_process_handle(); 578 579 // Check for static linked agent library 580 static bool find_builtin_agent(AgentLibrary *agent_lib, const char *syms[], 581 size_t syms_len); 582 583 // Find agent entry point 584 static void *find_agent_function(AgentLibrary *agent_lib, bool check_lib, 585 const char *syms[], size_t syms_len); 586 587 // Print out system information; they are called by fatal error handler. 588 // Output format may be different on different platforms. 589 static void print_os_info(outputStream* st); 590 static void print_os_info_brief(outputStream* st); 591 static void print_cpu_info(outputStream* st); 592 static void pd_print_cpu_info(outputStream* st); 593 static void print_memory_info(outputStream* st); 594 static void print_dll_info(outputStream* st); 595 static void print_environment_variables(outputStream* st, const char** env_list); 596 static void print_context(outputStream* st, void* context); 597 static void print_register_info(outputStream* st, void* context); 598 static void print_siginfo(outputStream* st, void* siginfo); 599 static void print_signal_handlers(outputStream* st, char* buf, size_t buflen); 600 static void print_date_and_time(outputStream* st); 601 602 static void print_location(outputStream* st, intptr_t x, bool verbose = false); 603 static size_t lasterror(char *buf, size_t len); 604 static int get_last_error(); 605 606 // Determines whether the calling process is being debugged by a user-mode debugger. 607 static bool is_debugger_attached(); 608 609 // wait for a key press if PauseAtExit is set 610 static void wait_for_keypress_at_exit(void); 611 612 // The following two functions are used by fatal error handler to trace 613 // native (C) frames. They are not part of frame.hpp/frame.cpp because 614 // frame.hpp/cpp assume thread is JavaThread, and also because different 615 // OS/compiler may have different convention or provide different API to 616 // walk C frames. 617 // 618 // We don't attempt to become a debugger, so we only follow frames if that 619 // does not require a lookup in the unwind table, which is part of the binary 620 // file but may be unsafe to read after a fatal error. So on x86, we can 621 // only walk stack if %ebp is used as frame pointer; on ia64, it's not 622 // possible to walk C stack without having the unwind table. 623 static bool is_first_C_frame(frame *fr); 624 static frame get_sender_for_C_frame(frame *fr); 625 626 // return current frame. pc() and sp() are set to NULL on failure. 627 static frame current_frame(); 628 629 static void print_hex_dump(outputStream* st, address start, address end, int unitsize); 630 631 // returns a string to describe the exception/signal; 632 // returns NULL if exception_code is not an OS exception/signal. 633 static const char* exception_name(int exception_code, char* buf, size_t buflen); 634 635 // Returns native Java library, loads if necessary 636 static void* native_java_library(); 637 638 // Fills in path to jvm.dll/libjvm.so (used by the Disassembler) 639 static void jvm_path(char *buf, jint buflen); 640 641 // Returns true if we are running in a headless jre. 642 static bool is_headless_jre(); 643 644 // JNI names 645 static void print_jni_name_prefix_on(outputStream* st, int args_size); 646 static void print_jni_name_suffix_on(outputStream* st, int args_size); 647 648 // Init os specific system properties values 649 static void init_system_properties_values(); 650 651 // IO operations, non-JVM_ version. 652 static int stat(const char* path, struct stat* sbuf); 653 static bool dir_is_empty(const char* path); 654 655 // IO operations on binary files 656 static int create_binary_file(const char* path, bool rewrite_existing); 657 static jlong current_file_offset(int fd); 658 static jlong seek_to_file_offset(int fd, jlong offset); 659 660 // Thread Local Storage 661 static int allocate_thread_local_storage(); 662 static void thread_local_storage_at_put(int index, void* value); 663 static void* thread_local_storage_at(int index); 664 static void free_thread_local_storage(int index); 665 666 // Retrieve native stack frames. 667 // Parameter: 668 // stack: an array to storage stack pointers. 669 // frames: size of above array. 670 // toSkip: number of stack frames to skip at the beginning. 671 // Return: number of stack frames captured. 672 static int get_native_stack(address* stack, int size, int toSkip = 0); 673 674 // General allocation (must be MT-safe) 675 static void* malloc (size_t size, MEMFLAGS flags, const NativeCallStack& stack); 676 static void* malloc (size_t size, MEMFLAGS flags); 677 static void* realloc (void *memblock, size_t size, MEMFLAGS flag, const NativeCallStack& stack); 678 static void* realloc (void *memblock, size_t size, MEMFLAGS flag); 679 680 static void free (void *memblock); 681 static bool check_heap(bool force = false); // verify C heap integrity 682 static char* strdup(const char *, MEMFLAGS flags = mtInternal); // Like strdup 683 // Like strdup, but exit VM when strdup() returns NULL 684 static char* strdup_check_oom(const char*, MEMFLAGS flags = mtInternal); 685 686 #ifndef PRODUCT 687 static julong num_mallocs; // # of calls to malloc/realloc 688 static julong alloc_bytes; // # of bytes allocated 689 static julong num_frees; // # of calls to free 690 static julong free_bytes; // # of bytes freed 691 #endif 692 693 // SocketInterface (ex HPI SocketInterface ) 694 static int socket(int domain, int type, int protocol); 695 static int socket_close(int fd); 696 static int recv(int fd, char* buf, size_t nBytes, uint flags); 697 static int send(int fd, char* buf, size_t nBytes, uint flags); 698 static int raw_send(int fd, char* buf, size_t nBytes, uint flags); 699 static int connect(int fd, struct sockaddr* him, socklen_t len); 700 static struct hostent* get_host_by_name(char* name); 701 702 // Support for signals (see JVM_RaiseSignal, JVM_RegisterSignal) 703 static void signal_init(); 704 static void signal_init_pd(); 705 static void signal_notify(int signal_number); 706 static void* signal(int signal_number, void* handler); 707 static void signal_raise(int signal_number); 708 static int signal_wait(); 709 static int signal_lookup(); 710 static void* user_handler(); 711 static void terminate_signal_thread(); 712 static int sigexitnum_pd(); 713 714 // random number generation 715 static long random(); // return 32bit pseudorandom number 716 static void init_random(long initval); // initialize random sequence 717 718 // Structured OS Exception support 719 static void os_exception_wrapper(java_call_t f, JavaValue* value, methodHandle* method, JavaCallArguments* args, Thread* thread); 720 721 // On Posix compatible OS it will simply check core dump limits while on Windows 722 // it will check if dump file can be created. Check or prepare a core dump to be 723 // taken at a later point in the same thread in os::abort(). Use the caller 724 // provided buffer as a scratch buffer. The status message which will be written 725 // into the error log either is file location or a short error message, depending 726 // on the checking result. 727 static void check_dump_limit(char* buffer, size_t bufferSize); 728 729 // Get the default path to the core file 730 // Returns the length of the string 731 static int get_core_path(char* buffer, size_t bufferSize); 732 733 // JVMTI & JVM monitoring and management support 734 // The thread_cpu_time() and current_thread_cpu_time() are only 735 // supported if is_thread_cpu_time_supported() returns true. 736 // They are not supported on Solaris T1. 737 738 // Thread CPU Time - return the fast estimate on a platform 739 // On Solaris - call gethrvtime (fast) - user time only 740 // On Linux - fast clock_gettime where available - user+sys 741 // - otherwise: very slow /proc fs - user+sys 742 // On Windows - GetThreadTimes - user+sys 743 static jlong current_thread_cpu_time(); 744 static jlong thread_cpu_time(Thread* t); 745 746 // Thread CPU Time with user_sys_cpu_time parameter. 747 // 748 // If user_sys_cpu_time is true, user+sys time is returned. 749 // Otherwise, only user time is returned 750 static jlong current_thread_cpu_time(bool user_sys_cpu_time); 751 static jlong thread_cpu_time(Thread* t, bool user_sys_cpu_time); 752 753 // Return a bunch of info about the timers. 754 // Note that the returned info for these two functions may be different 755 // on some platforms 756 static void current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr); 757 static void thread_cpu_time_info(jvmtiTimerInfo *info_ptr); 758 759 static bool is_thread_cpu_time_supported(); 760 761 // System loadavg support. Returns -1 if load average cannot be obtained. 762 static int loadavg(double loadavg[], int nelem); 763 764 // Hook for os specific jvm options that we don't want to abort on seeing 765 static bool obsolete_option(const JavaVMOption *option); 766 767 // Amount beyond the callee frame size that we bang the stack. 768 static int extra_bang_size_in_bytes(); 769 770 // Extensions 771 #include "runtime/os_ext.hpp" 772 773 public: 774 class CrashProtectionCallback : public StackObj { 775 public: 776 virtual void call() = 0; 777 }; 778 779 // Platform dependent stuff 780 #ifdef TARGET_OS_FAMILY_linux 781 # include "os_linux.hpp" 782 # include "os_posix.hpp" 783 #endif 784 #ifdef TARGET_OS_FAMILY_solaris 785 # include "os_solaris.hpp" 786 # include "os_posix.hpp" 787 #endif 788 #ifdef TARGET_OS_FAMILY_windows 789 # include "os_windows.hpp" 790 #endif 791 #ifdef TARGET_OS_FAMILY_aix 792 # include "os_aix.hpp" 793 # include "os_posix.hpp" 794 #endif 795 #ifdef TARGET_OS_FAMILY_bsd 796 # include "os_posix.hpp" 797 # include "os_bsd.hpp" 798 #endif 799 #ifdef TARGET_OS_ARCH_linux_x86 800 # include "os_linux_x86.hpp" 801 #endif 802 #ifdef TARGET_OS_ARCH_linux_sparc 803 # include "os_linux_sparc.hpp" 804 #endif 805 #ifdef TARGET_OS_ARCH_linux_zero 806 # include "os_linux_zero.hpp" 807 #endif 808 #ifdef TARGET_OS_ARCH_solaris_x86 809 # include "os_solaris_x86.hpp" 810 #endif 811 #ifdef TARGET_OS_ARCH_solaris_sparc 812 # include "os_solaris_sparc.hpp" 813 #endif 814 #ifdef TARGET_OS_ARCH_windows_x86 815 # include "os_windows_x86.hpp" 816 #endif 817 #ifdef TARGET_OS_ARCH_linux_arm 818 # include "os_linux_arm.hpp" 819 #endif 820 #ifdef TARGET_OS_ARCH_linux_ppc 821 # include "os_linux_ppc.hpp" 822 #endif 823 #ifdef TARGET_OS_ARCH_aix_ppc 824 # include "os_aix_ppc.hpp" 825 #endif 826 #ifdef TARGET_OS_ARCH_linux_aarch64 827 # include "os_linux_aarch64.hpp" 828 #endif 829 #ifdef TARGET_OS_ARCH_bsd_x86 830 # include "os_bsd_x86.hpp" 831 #endif 832 #ifdef TARGET_OS_ARCH_bsd_zero 833 # include "os_bsd_zero.hpp" 834 #endif 835 836 #ifndef OS_NATIVE_THREAD_CREATION_FAILED_MSG 837 #define OS_NATIVE_THREAD_CREATION_FAILED_MSG "unable to create native thread: possibly out of memory or process/resource limits reached" 838 #endif 839 840 public: 841 #ifndef PLATFORM_PRINT_NATIVE_STACK 842 // No platform-specific code for printing the native stack. 843 static bool platform_print_native_stack(outputStream* st, void* context, 844 char *buf, int buf_size) { 845 return false; 846 } 847 #endif 848 849 // debugging support (mostly used by debug.cpp but also fatal error handler) 850 static bool find(address pc, outputStream* st = tty); // OS specific function to make sense out of an address 851 852 static bool dont_yield(); // when true, JVM_Yield() is nop 853 static void print_statistics(); 854 855 // Thread priority helpers (implemented in OS-specific part) 856 static OSReturn set_native_priority(Thread* thread, int native_prio); 857 static OSReturn get_native_priority(const Thread* const thread, int* priority_ptr); 858 static int java_to_os_priority[CriticalPriority + 1]; 859 // Hint to the underlying OS that a task switch would not be good. 860 // Void return because it's a hint and can fail. 861 static void hint_no_preempt(); 862 static const char* native_thread_creation_failed_msg() { 863 return OS_NATIVE_THREAD_CREATION_FAILED_MSG; 864 } 865 866 // Used at creation if requested by the diagnostic flag PauseAtStartup. 867 // Causes the VM to wait until an external stimulus has been applied 868 // (for Unix, that stimulus is a signal, for Windows, an external 869 // ResumeThread call) 870 static void pause(); 871 872 // Builds a platform dependent Agent_OnLoad_<libname> function name 873 // which is used to find statically linked in agents. 874 static char* build_agent_function_name(const char *sym, const char *cname, 875 bool is_absolute_path); 876 877 class SuspendedThreadTaskContext { 878 public: 879 SuspendedThreadTaskContext(Thread* thread, void *ucontext) : _thread(thread), _ucontext(ucontext) {} 880 Thread* thread() const { return _thread; } 881 void* ucontext() const { return _ucontext; } 882 private: 883 Thread* _thread; 884 void* _ucontext; 885 }; 886 887 class SuspendedThreadTask { 888 public: 889 SuspendedThreadTask(Thread* thread) : _thread(thread), _done(false) {} 890 virtual ~SuspendedThreadTask() {} 891 void run(); 892 bool is_done() { return _done; } 893 virtual void do_task(const SuspendedThreadTaskContext& context) = 0; 894 protected: 895 private: 896 void internal_do_task(); 897 Thread* _thread; 898 bool _done; 899 }; 900 901 #ifndef TARGET_OS_FAMILY_windows 902 // Suspend/resume support 903 // Protocol: 904 // 905 // a thread starts in SR_RUNNING 906 // 907 // SR_RUNNING can go to 908 // * SR_SUSPEND_REQUEST when the WatcherThread wants to suspend it 909 // SR_SUSPEND_REQUEST can go to 910 // * SR_RUNNING if WatcherThread decides it waited for SR_SUSPENDED too long (timeout) 911 // * SR_SUSPENDED if the stopped thread receives the signal and switches state 912 // SR_SUSPENDED can go to 913 // * SR_WAKEUP_REQUEST when the WatcherThread has done the work and wants to resume 914 // SR_WAKEUP_REQUEST can go to 915 // * SR_RUNNING when the stopped thread receives the signal 916 // * SR_WAKEUP_REQUEST on timeout (resend the signal and try again) 917 class SuspendResume { 918 public: 919 enum State { 920 SR_RUNNING, 921 SR_SUSPEND_REQUEST, 922 SR_SUSPENDED, 923 SR_WAKEUP_REQUEST 924 }; 925 926 private: 927 volatile State _state; 928 929 private: 930 /* try to switch state from state "from" to state "to" 931 * returns the state set after the method is complete 932 */ 933 State switch_state(State from, State to); 934 935 public: 936 SuspendResume() : _state(SR_RUNNING) { } 937 938 State state() const { return _state; } 939 940 State request_suspend() { 941 return switch_state(SR_RUNNING, SR_SUSPEND_REQUEST); 942 } 943 944 State cancel_suspend() { 945 return switch_state(SR_SUSPEND_REQUEST, SR_RUNNING); 946 } 947 948 State suspended() { 949 return switch_state(SR_SUSPEND_REQUEST, SR_SUSPENDED); 950 } 951 952 State request_wakeup() { 953 return switch_state(SR_SUSPENDED, SR_WAKEUP_REQUEST); 954 } 955 956 State running() { 957 return switch_state(SR_WAKEUP_REQUEST, SR_RUNNING); 958 } 959 960 bool is_running() const { 961 return _state == SR_RUNNING; 962 } 963 964 bool is_suspend_request() const { 965 return _state == SR_SUSPEND_REQUEST; 966 } 967 968 bool is_suspended() const { 969 return _state == SR_SUSPENDED; 970 } 971 }; 972 #endif 973 974 975 protected: 976 static long _rand_seed; // seed for random number generator 977 static int _processor_count; // number of processors 978 979 static char* format_boot_path(const char* format_string, 980 const char* home, 981 int home_len, 982 char fileSep, 983 char pathSep); 984 static bool set_boot_path(char fileSep, char pathSep); 985 static char** split_path(const char* path, int* n); 986 987 }; 988 989 // Note that "PAUSE" is almost always used with synchronization 990 // so arguably we should provide Atomic::SpinPause() instead 991 // of the global SpinPause() with C linkage. 992 // It'd also be eligible for inlining on many platforms. 993 994 extern "C" int SpinPause(); 995 996 #endif // SHARE_VM_RUNTIME_OS_HPP