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/extendedPC.hpp" 30 #include "runtime/handles.hpp" 31 #include "utilities/top.hpp" 32 #ifdef TARGET_OS_FAMILY_linux 33 # include "jvm_linux.h" 34 # include <setjmp.h> 35 #endif 36 #ifdef TARGET_OS_FAMILY_solaris 37 # include "jvm_solaris.h" 38 # include <setjmp.h> 39 #endif 40 #ifdef TARGET_OS_FAMILY_windows 41 # include "jvm_windows.h" 42 #endif 43 #ifdef TARGET_OS_FAMILY_aix 44 # include "jvm_aix.h" 45 # include <setjmp.h> 46 #endif 47 #ifdef TARGET_OS_FAMILY_bsd 48 # include "jvm_bsd.h" 49 # include <setjmp.h> 50 # ifdef __APPLE__ 51 # include <mach/mach_time.h> 52 # endif 53 #endif 54 55 class AgentLibrary; 56 57 // os defines the interface to operating system; this includes traditional 58 // OS services (time, I/O) as well as other functionality with system- 59 // dependent code. 60 61 typedef void (*dll_func)(...); 62 63 class Thread; 64 class JavaThread; 65 class Event; 66 class DLL; 67 class FileHandle; 68 class NativeCallStack; 69 70 template<class E> class GrowableArray; 71 72 // %%%%% Moved ThreadState, START_FN, OSThread to new osThread.hpp. -- Rose 73 74 // Platform-independent error return values from OS functions 75 enum OSReturn { 76 OS_OK = 0, // Operation was successful 77 OS_ERR = -1, // Operation failed 78 OS_INTRPT = -2, // Operation was interrupted 79 OS_TIMEOUT = -3, // Operation timed out 80 OS_NOMEM = -5, // Operation failed for lack of memory 81 OS_NORESOURCE = -6 // Operation failed for lack of nonmemory resource 82 }; 83 84 enum ThreadPriority { // JLS 20.20.1-3 85 NoPriority = -1, // Initial non-priority value 86 MinPriority = 1, // Minimum priority 87 NormPriority = 5, // Normal (non-daemon) priority 88 NearMaxPriority = 9, // High priority, used for VMThread 89 MaxPriority = 10, // Highest priority, used for WatcherThread 90 // ensures that VMThread doesn't starve profiler 91 CriticalPriority = 11 // Critical thread priority 92 }; 93 94 // Executable parameter flag for os::commit_memory() and 95 // os::commit_memory_or_exit(). 96 const bool ExecMem = true; 97 98 // Typedef for structured exception handling support 99 typedef void (*java_call_t)(JavaValue* value, methodHandle* method, JavaCallArguments* args, Thread* thread); 100 101 class MallocTracker; 102 103 class os: AllStatic { 104 friend class VMStructs; 105 friend class MallocTracker; 106 public: 107 enum { page_sizes_max = 9 }; // Size of _page_sizes array (8 plus a sentinel) 108 109 private: 110 static OSThread* _starting_thread; 111 static address _polling_page; 112 static volatile int32_t * _mem_serialize_page; 113 static uintptr_t _serialize_page_mask; 114 public: 115 static size_t _page_sizes[page_sizes_max]; 116 117 private: 118 static void init_page_sizes(size_t default_page_size) { 119 _page_sizes[0] = default_page_size; 120 _page_sizes[1] = 0; // sentinel 121 } 122 123 static char* pd_reserve_memory(size_t bytes, char* addr = 0, 124 size_t alignment_hint = 0); 125 static char* pd_attempt_reserve_memory_at(size_t bytes, char* addr); 126 static void pd_split_reserved_memory(char *base, size_t size, 127 size_t split, bool realloc); 128 static bool pd_commit_memory(char* addr, size_t bytes, bool executable); 129 static bool pd_commit_memory(char* addr, size_t size, size_t alignment_hint, 130 bool executable); 131 // Same as pd_commit_memory() that either succeeds or calls 132 // vm_exit_out_of_memory() with the specified mesg. 133 static void pd_commit_memory_or_exit(char* addr, size_t bytes, 134 bool executable, const char* mesg); 135 static void pd_commit_memory_or_exit(char* addr, size_t size, 136 size_t alignment_hint, 137 bool executable, const char* mesg); 138 static bool pd_uncommit_memory(char* addr, size_t bytes); 139 static bool pd_release_memory(char* addr, size_t bytes); 140 141 static char* pd_map_memory(int fd, const char* file_name, size_t file_offset, 142 char *addr, size_t bytes, bool read_only = false, 143 bool allow_exec = false); 144 static char* pd_remap_memory(int fd, const char* file_name, size_t file_offset, 145 char *addr, size_t bytes, bool read_only, 146 bool allow_exec); 147 static bool pd_unmap_memory(char *addr, size_t bytes); 148 static void pd_free_memory(char *addr, size_t bytes, size_t alignment_hint); 149 static void pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint); 150 151 152 public: 153 static void init(void); // Called before command line parsing 154 static void init_before_ergo(void); // Called after command line parsing 155 // before VM ergonomics processing. 156 static jint init_2(void); // Called after command line parsing 157 // and VM ergonomics processing 158 static void init_globals(void) { // Called from init_globals() in init.cpp 159 init_globals_ext(); 160 } 161 162 // File names are case-insensitive on windows only 163 // Override me as needed 164 static int file_name_strcmp(const char* s1, const char* s2); 165 166 // get/unset environment variable 167 static bool getenv(const char* name, char* buffer, int len); 168 static bool unsetenv(const char* name); 169 170 static bool have_special_privileges(); 171 172 static jlong javaTimeMillis(); 173 static jlong javaTimeNanos(); 174 static void javaTimeNanos_info(jvmtiTimerInfo *info_ptr); 175 static void run_periodic_checks(); 176 static bool supports_monotonic_clock(); 177 178 179 // Returns the elapsed time in seconds since the vm started. 180 static double elapsedTime(); 181 182 // Returns real time in seconds since an arbitrary point 183 // in the past. 184 static bool getTimesSecs(double* process_real_time, 185 double* process_user_time, 186 double* process_system_time); 187 188 // Interface to the performance counter 189 static jlong elapsed_counter(); 190 static jlong elapsed_frequency(); 191 192 // The "virtual time" of a thread is the amount of time a thread has 193 // actually run. The first function indicates whether the OS supports 194 // this functionality for the current thread, and if so: 195 // * the second enables vtime tracking (if that is required). 196 // * the third tells whether vtime is enabled. 197 // * the fourth returns the elapsed virtual time for the current 198 // thread. 199 static bool supports_vtime(); 200 static bool enable_vtime(); 201 static bool vtime_enabled(); 202 static double elapsedVTime(); 203 204 // Return current local time in a string (YYYY-MM-DD HH:MM:SS). 205 // It is MT safe, but not async-safe, as reading time zone 206 // information may require a lock on some platforms. 207 static char* local_time_string(char *buf, size_t buflen); 208 static struct tm* localtime_pd (const time_t* clock, struct tm* res); 209 // Fill in buffer with current local time as an ISO-8601 string. 210 // E.g., YYYY-MM-DDThh:mm:ss.mmm+zzzz. 211 // Returns buffer, or NULL if it failed. 212 static char* iso8601_time(char* buffer, size_t buffer_length); 213 214 // Interface for detecting multiprocessor system 215 static inline bool is_MP() { 216 // During bootstrap if _processor_count is not yet initialized 217 // we claim to be MP as that is safest. If any platform has a 218 // stub generator that might be triggered in this phase and for 219 // which being declared MP when in fact not, is a problem - then 220 // the bootstrap routine for the stub generator needs to check 221 // the processor count directly and leave the bootstrap routine 222 // in place until called after initialization has ocurred. 223 return (_processor_count != 1) || AssumeMP; 224 } 225 static julong available_memory(); 226 static julong physical_memory(); 227 static bool has_allocatable_memory_limit(julong* limit); 228 static bool is_server_class_machine(); 229 230 // number of CPUs 231 static int processor_count() { 232 return _processor_count; 233 } 234 static void set_processor_count(int count) { _processor_count = count; } 235 236 // Returns the number of CPUs this process is currently allowed to run on. 237 // Note that on some OSes this can change dynamically. 238 static int active_processor_count(); 239 240 // Bind processes to processors. 241 // This is a two step procedure: 242 // first you generate a distribution of processes to processors, 243 // then you bind processes according to that distribution. 244 // Compute a distribution for number of processes to processors. 245 // Stores the processor id's into the distribution array argument. 246 // Returns true if it worked, false if it didn't. 247 static bool distribute_processes(uint length, uint* distribution); 248 // Binds the current process to a processor. 249 // Returns true if it worked, false if it didn't. 250 static bool bind_to_processor(uint processor_id); 251 252 // Give a name to the current thread. 253 static void set_native_thread_name(const char *name); 254 255 // Interface for stack banging (predetect possible stack overflow for 256 // exception processing) There are guard pages, and above that shadow 257 // pages for stack overflow checking. 258 static bool uses_stack_guard_pages(); 259 static bool allocate_stack_guard_pages(); 260 static void bang_stack_shadow_pages(); 261 static bool stack_shadow_pages_available(Thread *thread, methodHandle method); 262 263 // OS interface to Virtual Memory 264 265 // Return the default page size. 266 static int vm_page_size(); 267 268 // Returns the page size to use for a region of memory. 269 // region_size / min_pages will always be greater than or equal to the 270 // returned value. 271 static size_t page_size_for_region(size_t region_size, size_t min_pages); 272 273 // Return the largest page size that can be used 274 static size_t max_page_size() { 275 // The _page_sizes array is sorted in descending order. 276 return _page_sizes[0]; 277 } 278 279 // Returns the largest page size smaller than or equal to sz 280 static size_t largest_page_size_less_than(size_t sz); 281 282 // Methods for tracing page sizes returned by the above method; enabled by 283 // TracePageSizes. The region_{min,max}_size parameters should be the values 284 // passed to page_size_for_region() and page_size should be the result of that 285 // call. The (optional) base and size parameters should come from the 286 // ReservedSpace base() and size() methods. 287 static void trace_page_sizes(const char* str, const size_t* page_sizes, 288 int count) PRODUCT_RETURN; 289 static void trace_page_sizes(const char* str, const size_t region_min_size, 290 const size_t region_max_size, 291 const size_t page_size, 292 const char* base = NULL, 293 const size_t size = 0) PRODUCT_RETURN; 294 295 static int vm_allocation_granularity(); 296 static char* reserve_memory(size_t bytes, char* addr = 0, 297 size_t alignment_hint = 0); 298 static char* reserve_memory(size_t bytes, char* addr, 299 size_t alignment_hint, MEMFLAGS flags); 300 static char* reserve_memory_aligned(size_t size, size_t alignment); 301 static char* attempt_reserve_memory_at(size_t bytes, char* addr); 302 static void split_reserved_memory(char *base, size_t size, 303 size_t split, bool realloc); 304 static bool commit_memory(char* addr, size_t bytes, bool executable); 305 static bool commit_memory(char* addr, size_t size, size_t alignment_hint, 306 bool executable); 307 // Same as commit_memory() that either succeeds or calls 308 // vm_exit_out_of_memory() with the specified mesg. 309 static void commit_memory_or_exit(char* addr, size_t bytes, 310 bool executable, const char* mesg); 311 static void commit_memory_or_exit(char* addr, size_t size, 312 size_t alignment_hint, 313 bool executable, const char* mesg); 314 static bool uncommit_memory(char* addr, size_t bytes); 315 static bool release_memory(char* addr, size_t bytes); 316 317 enum ProtType { MEM_PROT_NONE, MEM_PROT_READ, MEM_PROT_RW, MEM_PROT_RWX }; 318 static bool protect_memory(char* addr, size_t bytes, ProtType prot, 319 bool is_committed = true); 320 321 static bool guard_memory(char* addr, size_t bytes); 322 static bool unguard_memory(char* addr, size_t bytes); 323 static bool create_stack_guard_pages(char* addr, size_t bytes); 324 static bool pd_create_stack_guard_pages(char* addr, size_t bytes); 325 static bool remove_stack_guard_pages(char* addr, size_t bytes); 326 327 static char* map_memory(int fd, const char* file_name, size_t file_offset, 328 char *addr, size_t bytes, bool read_only = false, 329 bool allow_exec = false); 330 static char* remap_memory(int fd, const char* file_name, size_t file_offset, 331 char *addr, size_t bytes, bool read_only, 332 bool allow_exec); 333 static bool unmap_memory(char *addr, size_t bytes); 334 static void free_memory(char *addr, size_t bytes, size_t alignment_hint); 335 static void realign_memory(char *addr, size_t bytes, size_t alignment_hint); 336 337 // NUMA-specific interface 338 static bool numa_has_static_binding(); 339 static bool numa_has_group_homing(); 340 static void numa_make_local(char *addr, size_t bytes, int lgrp_hint); 341 static void numa_make_global(char *addr, size_t bytes); 342 static size_t numa_get_groups_num(); 343 static size_t numa_get_leaf_groups(int *ids, size_t size); 344 static bool numa_topology_changed(); 345 static int numa_get_group_id(); 346 347 // Page manipulation 348 struct page_info { 349 size_t size; 350 int lgrp_id; 351 }; 352 static bool get_page_info(char *start, page_info* info); 353 static char* scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found); 354 355 static char* non_memory_address_word(); 356 // reserve, commit and pin the entire memory region 357 static char* reserve_memory_special(size_t size, size_t alignment, 358 char* addr, bool executable); 359 static bool release_memory_special(char* addr, size_t bytes); 360 static void large_page_init(); 361 static size_t large_page_size(); 362 static bool can_commit_large_page_memory(); 363 static bool can_execute_large_page_memory(); 364 365 // OS interface to polling page 366 static address get_polling_page() { return _polling_page; } 367 static void set_polling_page(address page) { _polling_page = page; } 368 static bool is_poll_address(address addr) { return addr >= _polling_page && addr < (_polling_page + os::vm_page_size()); } 369 static void make_polling_page_unreadable(); 370 static void make_polling_page_readable(); 371 372 // Routines used to serialize the thread state without using membars 373 static void serialize_thread_states(); 374 375 // Since we write to the serialize page from every thread, we 376 // want stores to be on unique cache lines whenever possible 377 // in order to minimize CPU cross talk. We pre-compute the 378 // amount to shift the thread* to make this offset unique to 379 // each thread. 380 static int get_serialize_page_shift_count() { 381 return SerializePageShiftCount; 382 } 383 384 static void set_serialize_page_mask(uintptr_t mask) { 385 _serialize_page_mask = mask; 386 } 387 388 static unsigned int get_serialize_page_mask() { 389 return _serialize_page_mask; 390 } 391 392 static void set_memory_serialize_page(address page); 393 394 static address get_memory_serialize_page() { 395 return (address)_mem_serialize_page; 396 } 397 398 static inline void write_memory_serialize_page(JavaThread *thread) { 399 uintptr_t page_offset = ((uintptr_t)thread >> 400 get_serialize_page_shift_count()) & 401 get_serialize_page_mask(); 402 *(volatile int32_t *)((uintptr_t)_mem_serialize_page+page_offset) = 1; 403 } 404 405 static bool is_memory_serialize_page(JavaThread *thread, address addr) { 406 if (UseMembar) return false; 407 // Previously this function calculated the exact address of this 408 // thread's serialize page, and checked if the faulting address 409 // was equal. However, some platforms mask off faulting addresses 410 // to the page size, so now we just check that the address is 411 // within the page. This makes the thread argument unnecessary, 412 // but we retain the NULL check to preserve existing behavior. 413 if (thread == NULL) return false; 414 address page = (address) _mem_serialize_page; 415 return addr >= page && addr < (page + os::vm_page_size()); 416 } 417 418 static void block_on_serialize_page_trap(); 419 420 // threads 421 422 enum ThreadType { 423 vm_thread, 424 cgc_thread, // Concurrent GC thread 425 pgc_thread, // Parallel GC thread 426 java_thread, 427 compiler_thread, 428 watcher_thread, 429 os_thread 430 }; 431 432 static bool create_thread(Thread* thread, 433 ThreadType thr_type, 434 size_t stack_size = 0); 435 static bool create_main_thread(JavaThread* thread); 436 static bool create_attached_thread(JavaThread* thread); 437 static void pd_start_thread(Thread* thread); 438 static void start_thread(Thread* thread); 439 440 static void initialize_thread(Thread* thr); 441 static void free_thread(OSThread* osthread); 442 443 // thread id on Linux/64bit is 64bit, on Windows and Solaris, it's 32bit 444 static intx current_thread_id(); 445 static int current_process_id(); 446 static int sleep(Thread* thread, jlong ms, bool interruptable); 447 // Short standalone OS sleep suitable for slow path spin loop. 448 // Ignores Thread.interrupt() (so keep it short). 449 // ms = 0, will sleep for the least amount of time allowed by the OS. 450 static void naked_short_sleep(jlong ms); 451 static void infinite_sleep(); // never returns, use with CAUTION 452 static void naked_yield () ; 453 static OSReturn set_priority(Thread* thread, ThreadPriority priority); 454 static OSReturn get_priority(const Thread* const thread, ThreadPriority& priority); 455 456 static void interrupt(Thread* thread); 457 static bool is_interrupted(Thread* thread, bool clear_interrupted); 458 459 static int pd_self_suspend_thread(Thread* thread); 460 461 static ExtendedPC fetch_frame_from_context(void* ucVoid, intptr_t** sp, intptr_t** fp); 462 static frame fetch_frame_from_context(void* ucVoid); 463 464 static ExtendedPC get_thread_pc(Thread *thread); 465 static void breakpoint(); 466 467 static address current_stack_pointer(); 468 static address current_stack_base(); 469 static size_t current_stack_size(); 470 471 static void verify_stack_alignment() PRODUCT_RETURN; 472 473 static int message_box(const char* title, const char* message); 474 static char* do_you_want_to_debug(const char* message); 475 476 // run cmd in a separate process and return its exit code; or -1 on failures 477 static int fork_and_exec(char *cmd); 478 479 // Call ::exit() on all platforms but Windows 480 static void exit(int num); 481 482 // Terminate the VM, but don't exit the process 483 static void shutdown(); 484 485 // Terminate with an error. Default is to generate a core file on platforms 486 // that support such things. This calls shutdown() and then aborts. 487 static void abort(bool dump_core = true); 488 489 // Die immediately, no exit hook, no abort hook, no cleanup. 490 static void die(); 491 492 // File i/o operations 493 static const int default_file_open_flags(); 494 static int open(const char *path, int oflag, int mode); 495 static FILE* open(int fd, const char* mode); 496 static int close(int fd); 497 static jlong lseek(int fd, jlong offset, int whence); 498 static char* native_path(char *path); 499 static int ftruncate(int fd, jlong length); 500 static int fsync(int fd); 501 static int available(int fd, jlong *bytes); 502 503 //File i/o operations 504 505 static size_t read(int fd, void *buf, unsigned int nBytes); 506 static size_t read_at(int fd, void *buf, unsigned int nBytes, jlong offset); 507 static size_t restartable_read(int fd, void *buf, unsigned int nBytes); 508 static size_t write(int fd, const void *buf, unsigned int nBytes); 509 510 // Reading directories. 511 static DIR* opendir(const char* dirname); 512 static int readdir_buf_size(const char *path); 513 static struct dirent* readdir(DIR* dirp, dirent* dbuf); 514 static int closedir(DIR* dirp); 515 516 // Dynamic library extension 517 static const char* dll_file_extension(); 518 519 static const char* get_temp_directory(); 520 static const char* get_current_directory(char *buf, size_t buflen); 521 522 // Builds a platform-specific full library path given a ld path and lib name 523 // Returns true if buffer contains full path to existing file, false otherwise 524 static bool dll_build_name(char* buffer, size_t size, 525 const char* pathname, const char* fname); 526 527 // Symbol lookup, find nearest function name; basically it implements 528 // dladdr() for all platforms. Name of the nearest function is copied 529 // to buf. Distance from its base address is optionally returned as offset. 530 // If function name is not found, buf[0] is set to '\0' and offset is 531 // set to -1 (if offset is non-NULL). 532 static bool dll_address_to_function_name(address addr, char* buf, 533 int buflen, int* offset); 534 535 // Locate DLL/DSO. On success, full path of the library is copied to 536 // buf, and offset is optionally set to be the distance between addr 537 // and the library's base address. On failure, buf[0] is set to '\0' 538 // and offset is set to -1 (if offset is non-NULL). 539 static bool dll_address_to_library_name(address addr, char* buf, 540 int buflen, int* offset); 541 542 // Find out whether the pc is in the static code for jvm.dll/libjvm.so. 543 static bool address_is_in_vm(address addr); 544 545 // Loads .dll/.so and 546 // in case of error it checks if .dll/.so was built for the 547 // same architecture as HotSpot is running on 548 static void* dll_load(const char *name, char *ebuf, int ebuflen); 549 550 // lookup symbol in a shared library 551 static void* dll_lookup(void* handle, const char* name); 552 553 // Unload library 554 static void dll_unload(void *lib); 555 556 // Callback for loaded module information 557 // Input parameters: 558 // char* module_file_name, 559 // address module_base_addr, 560 // address module_top_addr, 561 // void* param 562 typedef int (*LoadedModulesCallbackFunc)(const char *, address, address, void *); 563 564 static int get_loaded_modules_info(LoadedModulesCallbackFunc callback, void *param); 565 566 // Return the handle of this process 567 static void* get_default_process_handle(); 568 569 // Check for static linked agent library 570 static bool find_builtin_agent(AgentLibrary *agent_lib, const char *syms[], 571 size_t syms_len); 572 573 // Find agent entry point 574 static void *find_agent_function(AgentLibrary *agent_lib, bool check_lib, 575 const char *syms[], size_t syms_len); 576 577 // Print out system information; they are called by fatal error handler. 578 // Output format may be different on different platforms. 579 static void print_os_info(outputStream* st); 580 static void print_os_info_brief(outputStream* st); 581 static void print_cpu_info(outputStream* st); 582 static void pd_print_cpu_info(outputStream* st); 583 static void print_memory_info(outputStream* st); 584 static void print_dll_info(outputStream* st); 585 static void print_environment_variables(outputStream* st, const char** env_list, char* buffer, int len); 586 static void print_context(outputStream* st, void* context); 587 static void print_register_info(outputStream* st, void* context); 588 static void print_siginfo(outputStream* st, void* siginfo); 589 static void print_signal_handlers(outputStream* st, char* buf, size_t buflen); 590 static void print_date_and_time(outputStream* st); 591 592 static void print_location(outputStream* st, intptr_t x, bool verbose = false); 593 static size_t lasterror(char *buf, size_t len); 594 static int get_last_error(); 595 596 // Determines whether the calling process is being debugged by a user-mode debugger. 597 static bool is_debugger_attached(); 598 599 // wait for a key press if PauseAtExit is set 600 static void wait_for_keypress_at_exit(void); 601 602 // The following two functions are used by fatal error handler to trace 603 // native (C) frames. They are not part of frame.hpp/frame.cpp because 604 // frame.hpp/cpp assume thread is JavaThread, and also because different 605 // OS/compiler may have different convention or provide different API to 606 // walk C frames. 607 // 608 // We don't attempt to become a debugger, so we only follow frames if that 609 // does not require a lookup in the unwind table, which is part of the binary 610 // file but may be unsafe to read after a fatal error. So on x86, we can 611 // only walk stack if %ebp is used as frame pointer; on ia64, it's not 612 // possible to walk C stack without having the unwind table. 613 static bool is_first_C_frame(frame *fr); 614 static frame get_sender_for_C_frame(frame *fr); 615 616 // return current frame. pc() and sp() are set to NULL on failure. 617 static frame current_frame(); 618 619 static void print_hex_dump(outputStream* st, address start, address end, int unitsize); 620 621 // returns a string to describe the exception/signal; 622 // returns NULL if exception_code is not an OS exception/signal. 623 static const char* exception_name(int exception_code, char* buf, size_t buflen); 624 625 // Returns native Java library, loads if necessary 626 static void* native_java_library(); 627 628 // Fills in path to jvm.dll/libjvm.so (used by the Disassembler) 629 static void jvm_path(char *buf, jint buflen); 630 631 // Returns true if we are running in a headless jre. 632 static bool is_headless_jre(); 633 634 // JNI names 635 static void print_jni_name_prefix_on(outputStream* st, int args_size); 636 static void print_jni_name_suffix_on(outputStream* st, int args_size); 637 638 // Init os specific system properties values 639 static void init_system_properties_values(); 640 641 // IO operations, non-JVM_ version. 642 static int stat(const char* path, struct stat* sbuf); 643 static bool dir_is_empty(const char* path); 644 645 // IO operations on binary files 646 static int create_binary_file(const char* path, bool rewrite_existing); 647 static jlong current_file_offset(int fd); 648 static jlong seek_to_file_offset(int fd, jlong offset); 649 650 // Thread Local Storage 651 static int allocate_thread_local_storage(); 652 static void thread_local_storage_at_put(int index, void* value); 653 static void* thread_local_storage_at(int index); 654 static void free_thread_local_storage(int index); 655 656 // Retrieve native stack frames. 657 // Parameter: 658 // stack: an array to storage stack pointers. 659 // frames: size of above array. 660 // toSkip: number of stack frames to skip at the beginning. 661 // Return: number of stack frames captured. 662 static int get_native_stack(address* stack, int size, int toSkip = 0); 663 664 // General allocation (must be MT-safe) 665 static void* malloc (size_t size, MEMFLAGS flags, const NativeCallStack& stack); 666 static void* malloc (size_t size, MEMFLAGS flags); 667 static void* realloc (void *memblock, size_t size, MEMFLAGS flag, const NativeCallStack& stack); 668 static void* realloc (void *memblock, size_t size, MEMFLAGS flag); 669 670 static void free (void *memblock); 671 static bool check_heap(bool force = false); // verify C heap integrity 672 static char* strdup(const char *, MEMFLAGS flags = mtInternal); // Like strdup 673 // Like strdup, but exit VM when strdup() returns NULL 674 static char* strdup_check_oom(const char*, MEMFLAGS flags = mtInternal); 675 676 #ifndef PRODUCT 677 static julong num_mallocs; // # of calls to malloc/realloc 678 static julong alloc_bytes; // # of bytes allocated 679 static julong num_frees; // # of calls to free 680 static julong free_bytes; // # of bytes freed 681 #endif 682 683 // SocketInterface (ex HPI SocketInterface ) 684 static int socket(int domain, int type, int protocol); 685 static int socket_close(int fd); 686 static int recv(int fd, char* buf, size_t nBytes, uint flags); 687 static int send(int fd, char* buf, size_t nBytes, uint flags); 688 static int raw_send(int fd, char* buf, size_t nBytes, uint flags); 689 static int connect(int fd, struct sockaddr* him, socklen_t len); 690 static struct hostent* get_host_by_name(char* name); 691 692 // Support for signals (see JVM_RaiseSignal, JVM_RegisterSignal) 693 static void signal_init(); 694 static void signal_init_pd(); 695 static void signal_notify(int signal_number); 696 static void* signal(int signal_number, void* handler); 697 static void signal_raise(int signal_number); 698 static int signal_wait(); 699 static int signal_lookup(); 700 static void* user_handler(); 701 static void terminate_signal_thread(); 702 static int sigexitnum_pd(); 703 704 // random number generation 705 static long random(); // return 32bit pseudorandom number 706 static void init_random(long initval); // initialize random sequence 707 708 // Structured OS Exception support 709 static void os_exception_wrapper(java_call_t f, JavaValue* value, methodHandle* method, JavaCallArguments* args, Thread* thread); 710 711 // On Windows this will create an actual minidump, on Linux/Solaris it will simply check core dump limits 712 static void check_or_create_dump(void* exceptionRecord, void* contextRecord, char* buffer, size_t bufferSize); 713 714 // Get the default path to the core file 715 // Returns the length of the string 716 static int get_core_path(char* buffer, size_t bufferSize); 717 718 // JVMTI & JVM monitoring and management support 719 // The thread_cpu_time() and current_thread_cpu_time() are only 720 // supported if is_thread_cpu_time_supported() returns true. 721 // They are not supported on Solaris T1. 722 723 // Thread CPU Time - return the fast estimate on a platform 724 // On Solaris - call gethrvtime (fast) - user time only 725 // On Linux - fast clock_gettime where available - user+sys 726 // - otherwise: very slow /proc fs - user+sys 727 // On Windows - GetThreadTimes - user+sys 728 static jlong current_thread_cpu_time(); 729 static jlong thread_cpu_time(Thread* t); 730 731 // Thread CPU Time with user_sys_cpu_time parameter. 732 // 733 // If user_sys_cpu_time is true, user+sys time is returned. 734 // Otherwise, only user time is returned 735 static jlong current_thread_cpu_time(bool user_sys_cpu_time); 736 static jlong thread_cpu_time(Thread* t, bool user_sys_cpu_time); 737 738 // Return a bunch of info about the timers. 739 // Note that the returned info for these two functions may be different 740 // on some platforms 741 static void current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr); 742 static void thread_cpu_time_info(jvmtiTimerInfo *info_ptr); 743 744 static bool is_thread_cpu_time_supported(); 745 746 // System loadavg support. Returns -1 if load average cannot be obtained. 747 static int loadavg(double loadavg[], int nelem); 748 749 // Hook for os specific jvm options that we don't want to abort on seeing 750 static bool obsolete_option(const JavaVMOption *option); 751 752 // Amount beyond the callee frame size that we bang the stack. 753 static int extra_bang_size_in_bytes(); 754 755 // Extensions 756 #include "runtime/os_ext.hpp" 757 758 public: 759 class CrashProtectionCallback : public StackObj { 760 public: 761 virtual void call() = 0; 762 }; 763 764 // Platform dependent stuff 765 #ifdef TARGET_OS_FAMILY_linux 766 # include "os_linux.hpp" 767 # include "os_posix.hpp" 768 #endif 769 #ifdef TARGET_OS_FAMILY_solaris 770 # include "os_solaris.hpp" 771 # include "os_posix.hpp" 772 #endif 773 #ifdef TARGET_OS_FAMILY_windows 774 # include "os_windows.hpp" 775 #endif 776 #ifdef TARGET_OS_FAMILY_aix 777 # include "os_aix.hpp" 778 # include "os_posix.hpp" 779 #endif 780 #ifdef TARGET_OS_FAMILY_bsd 781 # include "os_posix.hpp" 782 # include "os_bsd.hpp" 783 #endif 784 #ifdef TARGET_OS_ARCH_linux_x86 785 # include "os_linux_x86.hpp" 786 #endif 787 #ifdef TARGET_OS_ARCH_linux_sparc 788 # include "os_linux_sparc.hpp" 789 #endif 790 #ifdef TARGET_OS_ARCH_linux_zero 791 # include "os_linux_zero.hpp" 792 #endif 793 #ifdef TARGET_OS_ARCH_solaris_x86 794 # include "os_solaris_x86.hpp" 795 #endif 796 #ifdef TARGET_OS_ARCH_solaris_sparc 797 # include "os_solaris_sparc.hpp" 798 #endif 799 #ifdef TARGET_OS_ARCH_windows_x86 800 # include "os_windows_x86.hpp" 801 #endif 802 #ifdef TARGET_OS_ARCH_linux_arm 803 # include "os_linux_arm.hpp" 804 #endif 805 #ifdef TARGET_OS_ARCH_linux_ppc 806 # include "os_linux_ppc.hpp" 807 #endif 808 #ifdef TARGET_OS_ARCH_aix_ppc 809 # include "os_aix_ppc.hpp" 810 #endif 811 #ifdef TARGET_OS_ARCH_bsd_x86 812 # include "os_bsd_x86.hpp" 813 #endif 814 #ifdef TARGET_OS_ARCH_bsd_zero 815 # include "os_bsd_zero.hpp" 816 #endif 817 818 #ifndef OS_NATIVE_THREAD_CREATION_FAILED_MSG 819 #define OS_NATIVE_THREAD_CREATION_FAILED_MSG "unable to create native thread: possibly out of memory or process/resource limits reached" 820 #endif 821 822 public: 823 #ifndef PLATFORM_PRINT_NATIVE_STACK 824 // No platform-specific code for printing the native stack. 825 static bool platform_print_native_stack(outputStream* st, void* context, 826 char *buf, int buf_size) { 827 return false; 828 } 829 #endif 830 831 // debugging support (mostly used by debug.cpp but also fatal error handler) 832 static bool find(address pc, outputStream* st = tty); // OS specific function to make sense out of an address 833 834 static bool dont_yield(); // when true, JVM_Yield() is nop 835 static void print_statistics(); 836 837 // Thread priority helpers (implemented in OS-specific part) 838 static OSReturn set_native_priority(Thread* thread, int native_prio); 839 static OSReturn get_native_priority(const Thread* const thread, int* priority_ptr); 840 static int java_to_os_priority[CriticalPriority + 1]; 841 // Hint to the underlying OS that a task switch would not be good. 842 // Void return because it's a hint and can fail. 843 static void hint_no_preempt(); 844 static const char* native_thread_creation_failed_msg() { 845 return OS_NATIVE_THREAD_CREATION_FAILED_MSG; 846 } 847 848 // Used at creation if requested by the diagnostic flag PauseAtStartup. 849 // Causes the VM to wait until an external stimulus has been applied 850 // (for Unix, that stimulus is a signal, for Windows, an external 851 // ResumeThread call) 852 static void pause(); 853 854 // Builds a platform dependent Agent_OnLoad_<libname> function name 855 // which is used to find statically linked in agents. 856 static char* build_agent_function_name(const char *sym, const char *cname, 857 bool is_absolute_path); 858 859 class SuspendedThreadTaskContext { 860 public: 861 SuspendedThreadTaskContext(Thread* thread, void *ucontext) : _thread(thread), _ucontext(ucontext) {} 862 Thread* thread() const { return _thread; } 863 void* ucontext() const { return _ucontext; } 864 private: 865 Thread* _thread; 866 void* _ucontext; 867 }; 868 869 class SuspendedThreadTask { 870 public: 871 SuspendedThreadTask(Thread* thread) : _thread(thread), _done(false) {} 872 virtual ~SuspendedThreadTask() {} 873 void run(); 874 bool is_done() { return _done; } 875 virtual void do_task(const SuspendedThreadTaskContext& context) = 0; 876 protected: 877 private: 878 void internal_do_task(); 879 Thread* _thread; 880 bool _done; 881 }; 882 883 #ifndef TARGET_OS_FAMILY_windows 884 // Suspend/resume support 885 // Protocol: 886 // 887 // a thread starts in SR_RUNNING 888 // 889 // SR_RUNNING can go to 890 // * SR_SUSPEND_REQUEST when the WatcherThread wants to suspend it 891 // SR_SUSPEND_REQUEST can go to 892 // * SR_RUNNING if WatcherThread decides it waited for SR_SUSPENDED too long (timeout) 893 // * SR_SUSPENDED if the stopped thread receives the signal and switches state 894 // SR_SUSPENDED can go to 895 // * SR_WAKEUP_REQUEST when the WatcherThread has done the work and wants to resume 896 // SR_WAKEUP_REQUEST can go to 897 // * SR_RUNNING when the stopped thread receives the signal 898 // * SR_WAKEUP_REQUEST on timeout (resend the signal and try again) 899 class SuspendResume { 900 public: 901 enum State { 902 SR_RUNNING, 903 SR_SUSPEND_REQUEST, 904 SR_SUSPENDED, 905 SR_WAKEUP_REQUEST 906 }; 907 908 private: 909 volatile State _state; 910 911 private: 912 /* try to switch state from state "from" to state "to" 913 * returns the state set after the method is complete 914 */ 915 State switch_state(State from, State to); 916 917 public: 918 SuspendResume() : _state(SR_RUNNING) { } 919 920 State state() const { return _state; } 921 922 State request_suspend() { 923 return switch_state(SR_RUNNING, SR_SUSPEND_REQUEST); 924 } 925 926 State cancel_suspend() { 927 return switch_state(SR_SUSPEND_REQUEST, SR_RUNNING); 928 } 929 930 State suspended() { 931 return switch_state(SR_SUSPEND_REQUEST, SR_SUSPENDED); 932 } 933 934 State request_wakeup() { 935 return switch_state(SR_SUSPENDED, SR_WAKEUP_REQUEST); 936 } 937 938 State running() { 939 return switch_state(SR_WAKEUP_REQUEST, SR_RUNNING); 940 } 941 942 bool is_running() const { 943 return _state == SR_RUNNING; 944 } 945 946 bool is_suspend_request() const { 947 return _state == SR_SUSPEND_REQUEST; 948 } 949 950 bool is_suspended() const { 951 return _state == SR_SUSPENDED; 952 } 953 }; 954 #endif 955 956 957 protected: 958 static long _rand_seed; // seed for random number generator 959 static int _processor_count; // number of processors 960 961 static char* format_boot_path(const char* format_string, 962 const char* home, 963 int home_len, 964 char fileSep, 965 char pathSep); 966 static bool set_boot_path(char fileSep, char pathSep); 967 static char** split_path(const char* path, int* n); 968 969 }; 970 971 // Note that "PAUSE" is almost always used with synchronization 972 // so arguably we should provide Atomic::SpinPause() instead 973 // of the global SpinPause() with C linkage. 974 // It'd also be eligible for inlining on many platforms. 975 976 extern "C" int SpinPause(); 977 978 #endif // SHARE_VM_RUNTIME_OS_HPP