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 # include <mach/mach_time.h> 52 #endif 53 54 class AgentLibrary; 55 56 // os defines the interface to operating system; this includes traditional 57 // OS services (time, I/O) as well as other functionality with system- 58 // dependent code. 59 60 typedef void (*dll_func)(...); 61 62 class Thread; 63 class JavaThread; 64 class Event; 65 class DLL; 66 class FileHandle; 67 template<class E> class GrowableArray; 68 69 // %%%%% Moved ThreadState, START_FN, OSThread to new osThread.hpp. -- Rose 70 71 // Platform-independent error return values from OS functions 72 enum OSReturn { 73 OS_OK = 0, // Operation was successful 74 OS_ERR = -1, // Operation failed 75 OS_INTRPT = -2, // Operation was interrupted 76 OS_TIMEOUT = -3, // Operation timed out 77 OS_NOMEM = -5, // Operation failed for lack of memory 78 OS_NORESOURCE = -6 // Operation failed for lack of nonmemory resource 79 }; 80 81 enum ThreadPriority { // JLS 20.20.1-3 82 NoPriority = -1, // Initial non-priority value 83 MinPriority = 1, // Minimum priority 84 NormPriority = 5, // Normal (non-daemon) priority 85 NearMaxPriority = 9, // High priority, used for VMThread 86 MaxPriority = 10, // Highest priority, used for WatcherThread 87 // ensures that VMThread doesn't starve profiler 88 CriticalPriority = 11 // Critical thread priority 89 }; 90 91 // Executable parameter flag for os::commit_memory() and 92 // os::commit_memory_or_exit(). 93 const bool ExecMem = true; 94 95 // Typedef for structured exception handling support 96 typedef void (*java_call_t)(JavaValue* value, methodHandle* method, JavaCallArguments* args, Thread* thread); 97 98 class os: AllStatic { 99 friend class VMStructs; 100 101 public: 102 enum { page_sizes_max = 9 }; // Size of _page_sizes array (8 plus a sentinel) 103 104 private: 105 static OSThread* _starting_thread; 106 static address _polling_page; 107 static volatile int32_t * _mem_serialize_page; 108 static uintptr_t _serialize_page_mask; 109 public: 110 static size_t _page_sizes[page_sizes_max]; 111 112 private: 113 static void init_page_sizes(size_t default_page_size) { 114 _page_sizes[0] = default_page_size; 115 _page_sizes[1] = 0; // sentinel 116 } 117 118 static char* pd_reserve_memory(size_t bytes, char* addr = 0, 119 size_t alignment_hint = 0); 120 static char* pd_attempt_reserve_memory_at(size_t bytes, char* addr); 121 static void pd_split_reserved_memory(char *base, size_t size, 122 size_t split, bool realloc); 123 static bool pd_commit_memory(char* addr, size_t bytes, bool executable); 124 static bool pd_commit_memory(char* addr, size_t size, size_t alignment_hint, 125 bool executable); 126 // Same as pd_commit_memory() that either succeeds or calls 127 // vm_exit_out_of_memory() with the specified mesg. 128 static void pd_commit_memory_or_exit(char* addr, size_t bytes, 129 bool executable, const char* mesg); 130 static void pd_commit_memory_or_exit(char* addr, size_t size, 131 size_t alignment_hint, 132 bool executable, const char* mesg); 133 static bool pd_uncommit_memory(char* addr, size_t bytes); 134 static bool pd_release_memory(char* addr, size_t bytes); 135 136 static char* pd_map_memory(int fd, const char* file_name, size_t file_offset, 137 char *addr, size_t bytes, bool read_only = false, 138 bool allow_exec = false); 139 static char* pd_remap_memory(int fd, const char* file_name, size_t file_offset, 140 char *addr, size_t bytes, bool read_only, 141 bool allow_exec); 142 static bool pd_unmap_memory(char *addr, size_t bytes); 143 static void pd_free_memory(char *addr, size_t bytes, size_t alignment_hint); 144 static void pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint); 145 146 147 public: 148 static void init(void); // Called before command line parsing 149 static void init_before_ergo(void); // Called after command line parsing 150 // before VM ergonomics processing. 151 static jint init_2(void); // Called after command line parsing 152 // and VM ergonomics processing 153 static void init_globals(void) { // Called from init_globals() in init.cpp 154 init_globals_ext(); 155 } 156 static void init_3(void); // Called at the end of vm init 157 158 // File names are case-insensitive on windows only 159 // Override me as needed 160 static int file_name_strcmp(const char* s1, const char* s2); 161 162 static bool getenv(const char* name, char* buffer, int len); 163 static bool have_special_privileges(); 164 165 static jlong javaTimeMillis(); 166 static jlong javaTimeNanos(); 167 static void javaTimeNanos_info(jvmtiTimerInfo *info_ptr); 168 static void run_periodic_checks(); 169 static bool supports_monotonic_clock(); 170 171 172 // Returns the elapsed time in seconds since the vm started. 173 static double elapsedTime(); 174 175 // Returns real time in seconds since an arbitrary point 176 // in the past. 177 static bool getTimesSecs(double* process_real_time, 178 double* process_user_time, 179 double* process_system_time); 180 181 // Interface to the performance counter 182 static jlong elapsed_counter(); 183 static jlong elapsed_frequency(); 184 185 // The "virtual time" of a thread is the amount of time a thread has 186 // actually run. The first function indicates whether the OS supports 187 // this functionality for the current thread, and if so: 188 // * the second enables vtime tracking (if that is required). 189 // * the third tells whether vtime is enabled. 190 // * the fourth returns the elapsed virtual time for the current 191 // thread. 192 static bool supports_vtime(); 193 static bool enable_vtime(); 194 static bool vtime_enabled(); 195 static double elapsedVTime(); 196 197 // Return current local time in a string (YYYY-MM-DD HH:MM:SS). 198 // It is MT safe, but not async-safe, as reading time zone 199 // information may require a lock on some platforms. 200 static char* local_time_string(char *buf, size_t buflen); 201 static struct tm* localtime_pd (const time_t* clock, struct tm* res); 202 // Fill in buffer with current local time as an ISO-8601 string. 203 // E.g., YYYY-MM-DDThh:mm:ss.mmm+zzzz. 204 // Returns buffer, or NULL if it failed. 205 static char* iso8601_time(char* buffer, size_t buffer_length); 206 207 // Interface for detecting multiprocessor system 208 static inline bool is_MP() { 209 assert(_processor_count > 0, "invalid processor count"); 210 return _processor_count > 1 || AssumeMP; 211 } 212 static julong available_memory(); 213 static julong physical_memory(); 214 static bool has_allocatable_memory_limit(julong* limit); 215 static bool is_server_class_machine(); 216 217 // number of CPUs 218 static int processor_count() { 219 return _processor_count; 220 } 221 static void set_processor_count(int count) { _processor_count = count; } 222 223 // Returns the number of CPUs this process is currently allowed to run on. 224 // Note that on some OSes this can change dynamically. 225 static int active_processor_count(); 226 227 // Bind processes to processors. 228 // This is a two step procedure: 229 // first you generate a distribution of processes to processors, 230 // then you bind processes according to that distribution. 231 // Compute a distribution for number of processes to processors. 232 // Stores the processor id's into the distribution array argument. 233 // Returns true if it worked, false if it didn't. 234 static bool distribute_processes(uint length, uint* distribution); 235 // Binds the current process to a processor. 236 // Returns true if it worked, false if it didn't. 237 static bool bind_to_processor(uint processor_id); 238 239 // Give a name to the current thread. 240 static void set_native_thread_name(const char *name); 241 242 // Interface for stack banging (predetect possible stack overflow for 243 // exception processing) There are guard pages, and above that shadow 244 // pages for stack overflow checking. 245 static bool uses_stack_guard_pages(); 246 static bool allocate_stack_guard_pages(); 247 static void bang_stack_shadow_pages(); 248 static bool stack_shadow_pages_available(Thread *thread, methodHandle method); 249 250 // OS interface to Virtual Memory 251 252 // Return the default page size. 253 static int vm_page_size(); 254 255 // Return the page size to use for a region of memory. The min_pages argument 256 // is a hint intended to limit fragmentation; it says the returned page size 257 // should be <= region_max_size / min_pages. Because min_pages is a hint, 258 // this routine may return a size larger than region_max_size / min_pages. 259 // 260 // The current implementation ignores min_pages if a larger page size is an 261 // exact multiple of both region_min_size and region_max_size. This allows 262 // larger pages to be used when doing so would not cause fragmentation; in 263 // particular, a single page can be used when region_min_size == 264 // region_max_size == a supported page size. 265 static size_t page_size_for_region(size_t region_min_size, 266 size_t region_max_size, 267 uint min_pages); 268 // Return the largest page size that can be used 269 static size_t max_page_size() { 270 // The _page_sizes array is sorted in descending order. 271 return _page_sizes[0]; 272 } 273 274 // Methods for tracing page sizes returned by the above method; enabled by 275 // TracePageSizes. The region_{min,max}_size parameters should be the values 276 // passed to page_size_for_region() and page_size should be the result of that 277 // call. The (optional) base and size parameters should come from the 278 // ReservedSpace base() and size() methods. 279 static void trace_page_sizes(const char* str, const size_t* page_sizes, 280 int count) PRODUCT_RETURN; 281 static void trace_page_sizes(const char* str, const size_t region_min_size, 282 const size_t region_max_size, 283 const size_t page_size, 284 const char* base = NULL, 285 const size_t size = 0) PRODUCT_RETURN; 286 287 static int vm_allocation_granularity(); 288 static char* reserve_memory(size_t bytes, char* addr = 0, 289 size_t alignment_hint = 0); 290 static char* reserve_memory(size_t bytes, char* addr, 291 size_t alignment_hint, MEMFLAGS flags); 292 static char* reserve_memory_aligned(size_t size, size_t alignment); 293 static char* attempt_reserve_memory_at(size_t bytes, char* addr); 294 static void split_reserved_memory(char *base, size_t size, 295 size_t split, bool realloc); 296 static bool commit_memory(char* addr, size_t bytes, bool executable); 297 static bool commit_memory(char* addr, size_t size, size_t alignment_hint, 298 bool executable); 299 // Same as commit_memory() that either succeeds or calls 300 // vm_exit_out_of_memory() with the specified mesg. 301 static void commit_memory_or_exit(char* addr, size_t bytes, 302 bool executable, const char* mesg); 303 static void commit_memory_or_exit(char* addr, size_t size, 304 size_t alignment_hint, 305 bool executable, const char* mesg); 306 static bool uncommit_memory(char* addr, size_t bytes); 307 static bool release_memory(char* addr, size_t bytes); 308 309 enum ProtType { MEM_PROT_NONE, MEM_PROT_READ, MEM_PROT_RW, MEM_PROT_RWX }; 310 static bool protect_memory(char* addr, size_t bytes, ProtType prot, 311 bool is_committed = true); 312 313 static bool guard_memory(char* addr, size_t bytes); 314 static bool unguard_memory(char* addr, size_t bytes); 315 static bool create_stack_guard_pages(char* addr, size_t bytes); 316 static bool pd_create_stack_guard_pages(char* addr, size_t bytes); 317 static bool remove_stack_guard_pages(char* addr, size_t bytes); 318 319 static char* map_memory(int fd, const char* file_name, size_t file_offset, 320 char *addr, size_t bytes, bool read_only = false, 321 bool allow_exec = false); 322 static char* remap_memory(int fd, const char* file_name, size_t file_offset, 323 char *addr, size_t bytes, bool read_only, 324 bool allow_exec); 325 static bool unmap_memory(char *addr, size_t bytes); 326 static void free_memory(char *addr, size_t bytes, size_t alignment_hint); 327 static void realign_memory(char *addr, size_t bytes, size_t alignment_hint); 328 329 // NUMA-specific interface 330 static bool numa_has_static_binding(); 331 static bool numa_has_group_homing(); 332 static void numa_make_local(char *addr, size_t bytes, int lgrp_hint); 333 static void numa_make_global(char *addr, size_t bytes); 334 static size_t numa_get_groups_num(); 335 static size_t numa_get_leaf_groups(int *ids, size_t size); 336 static bool numa_topology_changed(); 337 static int numa_get_group_id(); 338 339 // Page manipulation 340 struct page_info { 341 size_t size; 342 int lgrp_id; 343 }; 344 static bool get_page_info(char *start, page_info* info); 345 static char* scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found); 346 347 static char* non_memory_address_word(); 348 // reserve, commit and pin the entire memory region 349 static char* reserve_memory_special(size_t size, size_t alignment, 350 char* addr, bool executable); 351 static bool release_memory_special(char* addr, size_t bytes); 352 static void large_page_init(); 353 static size_t large_page_size(); 354 static bool can_commit_large_page_memory(); 355 static bool can_execute_large_page_memory(); 356 357 // OS interface to polling page 358 static address get_polling_page() { return _polling_page; } 359 static void set_polling_page(address page) { _polling_page = page; } 360 static bool is_poll_address(address addr) { return addr >= _polling_page && addr < (_polling_page + os::vm_page_size()); } 361 static void make_polling_page_unreadable(); 362 static void make_polling_page_readable(); 363 364 // Routines used to serialize the thread state without using membars 365 static void serialize_thread_states(); 366 367 // Since we write to the serialize page from every thread, we 368 // want stores to be on unique cache lines whenever possible 369 // in order to minimize CPU cross talk. We pre-compute the 370 // amount to shift the thread* to make this offset unique to 371 // each thread. 372 static int get_serialize_page_shift_count() { 373 return SerializePageShiftCount; 374 } 375 376 static void set_serialize_page_mask(uintptr_t mask) { 377 _serialize_page_mask = mask; 378 } 379 380 static unsigned int get_serialize_page_mask() { 381 return _serialize_page_mask; 382 } 383 384 static void set_memory_serialize_page(address page); 385 386 static address get_memory_serialize_page() { 387 return (address)_mem_serialize_page; 388 } 389 390 static inline void write_memory_serialize_page(JavaThread *thread) { 391 uintptr_t page_offset = ((uintptr_t)thread >> 392 get_serialize_page_shift_count()) & 393 get_serialize_page_mask(); 394 *(volatile int32_t *)((uintptr_t)_mem_serialize_page+page_offset) = 1; 395 } 396 397 static bool is_memory_serialize_page(JavaThread *thread, address addr) { 398 if (UseMembar) return false; 399 // Previously this function calculated the exact address of this 400 // thread's serialize page, and checked if the faulting address 401 // was equal. However, some platforms mask off faulting addresses 402 // to the page size, so now we just check that the address is 403 // within the page. This makes the thread argument unnecessary, 404 // but we retain the NULL check to preserve existing behavior. 405 if (thread == NULL) return false; 406 address page = (address) _mem_serialize_page; 407 return addr >= page && addr < (page + os::vm_page_size()); 408 } 409 410 static void block_on_serialize_page_trap(); 411 412 // threads 413 414 enum ThreadType { 415 vm_thread, 416 cgc_thread, // Concurrent GC thread 417 pgc_thread, // Parallel GC thread 418 java_thread, 419 compiler_thread, 420 watcher_thread, 421 os_thread 422 }; 423 424 static bool create_thread(Thread* thread, 425 ThreadType thr_type, 426 size_t stack_size = 0); 427 static bool create_main_thread(JavaThread* thread); 428 static bool create_attached_thread(JavaThread* thread); 429 static void pd_start_thread(Thread* thread); 430 static void start_thread(Thread* thread); 431 432 static void initialize_thread(Thread* thr); 433 static void free_thread(OSThread* osthread); 434 435 // thread id on Linux/64bit is 64bit, on Windows and Solaris, it's 32bit 436 static intx current_thread_id(); 437 static int current_process_id(); 438 static int sleep(Thread* thread, jlong ms, bool interruptable); 439 // Short standalone OS sleep suitable for slow path spin loop. 440 // Ignores Thread.interrupt() (so keep it short). 441 // ms = 0, will sleep for the least amount of time allowed by the OS. 442 static void naked_short_sleep(jlong ms); 443 static void infinite_sleep(); // never returns, use with CAUTION 444 static void yield(); // Yields to all threads with same priority 445 enum YieldResult { 446 YIELD_SWITCHED = 1, // caller descheduled, other ready threads exist & ran 447 YIELD_NONEREADY = 0, // No other runnable/ready threads. 448 // platform-specific yield return immediately 449 YIELD_UNKNOWN = -1 // Unknown: platform doesn't support _SWITCHED or _NONEREADY 450 // YIELD_SWITCHED and YIELD_NONREADY imply the platform supports a "strong" 451 // yield that can be used in lieu of blocking. 452 } ; 453 static YieldResult NakedYield () ; 454 static void yield_all(); // Yields to all other threads including lower priority 455 // (for the default scheduling policy) 456 static OSReturn set_priority(Thread* thread, ThreadPriority priority); 457 static OSReturn get_priority(const Thread* const thread, ThreadPriority& priority); 458 459 static void interrupt(Thread* thread); 460 static bool is_interrupted(Thread* thread, bool clear_interrupted); 461 462 static int pd_self_suspend_thread(Thread* thread); 463 464 static ExtendedPC fetch_frame_from_context(void* ucVoid, intptr_t** sp, intptr_t** fp); 465 static frame fetch_frame_from_context(void* ucVoid); 466 467 static ExtendedPC get_thread_pc(Thread *thread); 468 static void breakpoint(); 469 470 static address current_stack_pointer(); 471 static address current_stack_base(); 472 static size_t current_stack_size(); 473 474 static void verify_stack_alignment() PRODUCT_RETURN; 475 476 static int message_box(const char* title, const char* message); 477 static char* do_you_want_to_debug(const char* message); 478 479 // run cmd in a separate process and return its exit code; or -1 on failures 480 static int fork_and_exec(char *cmd); 481 482 // Set file to send error reports. 483 static void set_error_file(const char *logfile); 484 485 // os::exit() is merged with vm_exit() 486 // static void exit(int num); 487 488 // Terminate the VM, but don't exit the process 489 static void shutdown(); 490 491 // Terminate with an error. Default is to generate a core file on platforms 492 // that support such things. This calls shutdown() and then aborts. 493 static void abort(bool dump_core = true); 494 495 // Die immediately, no exit hook, no abort hook, no cleanup. 496 static void die(); 497 498 // File i/o operations 499 static const int default_file_open_flags(); 500 static int open(const char *path, int oflag, int mode); 501 static FILE* open(int fd, const char* mode); 502 static int close(int fd); 503 static jlong lseek(int fd, jlong offset, int whence); 504 static char* native_path(char *path); 505 static int ftruncate(int fd, jlong length); 506 static int fsync(int fd); 507 static int available(int fd, jlong *bytes); 508 509 //File i/o operations 510 511 static size_t read(int fd, void *buf, unsigned int nBytes); 512 static size_t restartable_read(int fd, void *buf, unsigned int nBytes); 513 static size_t write(int fd, const void *buf, unsigned int nBytes); 514 515 // Reading directories. 516 static DIR* opendir(const char* dirname); 517 static int readdir_buf_size(const char *path); 518 static struct dirent* readdir(DIR* dirp, dirent* dbuf); 519 static int closedir(DIR* dirp); 520 521 // Dynamic library extension 522 static const char* dll_file_extension(); 523 524 static const char* get_temp_directory(); 525 static const char* get_current_directory(char *buf, size_t buflen); 526 527 // Builds a platform-specific full library path given a ld path and lib name 528 // Returns true if buffer contains full path to existing file, false otherwise 529 static bool dll_build_name(char* buffer, size_t size, 530 const char* pathname, const char* fname); 531 532 // Symbol lookup, find nearest function name; basically it implements 533 // dladdr() for all platforms. Name of the nearest function is copied 534 // to buf. Distance from its base address is optionally returned as offset. 535 // If function name is not found, buf[0] is set to '\0' and offset is 536 // set to -1 (if offset is non-NULL). 537 static bool dll_address_to_function_name(address addr, char* buf, 538 int buflen, int* offset); 539 540 // Locate DLL/DSO. On success, full path of the library is copied to 541 // buf, and offset is optionally set to be the distance between addr 542 // and the library's base address. On failure, buf[0] is set to '\0' 543 // and offset is set to -1 (if offset is non-NULL). 544 static bool dll_address_to_library_name(address addr, char* buf, 545 int buflen, int* offset); 546 547 // Find out whether the pc is in the static code for jvm.dll/libjvm.so. 548 static bool address_is_in_vm(address addr); 549 550 // Loads .dll/.so and 551 // in case of error it checks if .dll/.so was built for the 552 // same architecture as HotSpot is running on 553 static void* dll_load(const char *name, char *ebuf, int ebuflen); 554 555 // lookup symbol in a shared library 556 static void* dll_lookup(void* handle, const char* name); 557 558 // Unload library 559 static void dll_unload(void *lib); 560 561 // Return the handle of this process 562 static void* get_default_process_handle(); 563 564 // Check for static linked agent library 565 static bool find_builtin_agent(AgentLibrary *agent_lib, const char *syms[], 566 size_t syms_len); 567 568 // Find agent entry point 569 static void *find_agent_function(AgentLibrary *agent_lib, bool check_lib, 570 const char *syms[], size_t syms_len); 571 572 // Print out system information; they are called by fatal error handler. 573 // Output format may be different on different platforms. 574 static void print_os_info(outputStream* st); 575 static void print_os_info_brief(outputStream* st); 576 static void print_cpu_info(outputStream* st); 577 static void pd_print_cpu_info(outputStream* st); 578 static void print_memory_info(outputStream* st); 579 static void print_dll_info(outputStream* st); 580 static void print_environment_variables(outputStream* st, const char** env_list, char* buffer, int len); 581 static void print_context(outputStream* st, void* context); 582 static void print_register_info(outputStream* st, void* context); 583 static void print_siginfo(outputStream* st, void* siginfo); 584 static void print_signal_handlers(outputStream* st, char* buf, size_t buflen); 585 static void print_date_and_time(outputStream* st); 586 587 static void print_location(outputStream* st, intptr_t x, bool verbose = false); 588 static size_t lasterror(char *buf, size_t len); 589 static int get_last_error(); 590 591 // Determines whether the calling process is being debugged by a user-mode debugger. 592 static bool is_debugger_attached(); 593 594 // wait for a key press if PauseAtExit is set 595 static void wait_for_keypress_at_exit(void); 596 597 // The following two functions are used by fatal error handler to trace 598 // native (C) frames. They are not part of frame.hpp/frame.cpp because 599 // frame.hpp/cpp assume thread is JavaThread, and also because different 600 // OS/compiler may have different convention or provide different API to 601 // walk C frames. 602 // 603 // We don't attempt to become a debugger, so we only follow frames if that 604 // does not require a lookup in the unwind table, which is part of the binary 605 // file but may be unsafe to read after a fatal error. So on x86, we can 606 // only walk stack if %ebp is used as frame pointer; on ia64, it's not 607 // possible to walk C stack without having the unwind table. 608 static bool is_first_C_frame(frame *fr); 609 static frame get_sender_for_C_frame(frame *fr); 610 611 // return current frame. pc() and sp() are set to NULL on failure. 612 static frame current_frame(); 613 614 static void print_hex_dump(outputStream* st, address start, address end, int unitsize); 615 616 // returns a string to describe the exception/signal; 617 // returns NULL if exception_code is not an OS exception/signal. 618 static const char* exception_name(int exception_code, char* buf, size_t buflen); 619 620 // Returns native Java library, loads if necessary 621 static void* native_java_library(); 622 623 // Fills in path to jvm.dll/libjvm.so (used by the Disassembler) 624 static void jvm_path(char *buf, jint buflen); 625 626 // Returns true if we are running in a headless jre. 627 static bool is_headless_jre(); 628 629 // JNI names 630 static void print_jni_name_prefix_on(outputStream* st, int args_size); 631 static void print_jni_name_suffix_on(outputStream* st, int args_size); 632 633 // File conventions 634 static const char* file_separator(); 635 static const char* line_separator(); 636 static const char* path_separator(); 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 // Stack walk 657 static address get_caller_pc(int n = 0); 658 659 // General allocation (must be MT-safe) 660 static void* malloc (size_t size, MEMFLAGS flags, address caller_pc = 0); 661 static void* realloc (void *memblock, size_t size, MEMFLAGS flags, address caller_pc = 0); 662 static void free (void *memblock, MEMFLAGS flags = mtNone); 663 static bool check_heap(bool force = false); // verify C heap integrity 664 static char* strdup(const char *, MEMFLAGS flags = mtInternal); // Like strdup 665 666 #ifndef PRODUCT 667 static julong num_mallocs; // # of calls to malloc/realloc 668 static julong alloc_bytes; // # of bytes allocated 669 static julong num_frees; // # of calls to free 670 static julong free_bytes; // # of bytes freed 671 #endif 672 673 // SocketInterface (ex HPI SocketInterface ) 674 static int socket(int domain, int type, int protocol); 675 static int socket_close(int fd); 676 static int socket_shutdown(int fd, int howto); 677 static int recv(int fd, char* buf, size_t nBytes, uint flags); 678 static int send(int fd, char* buf, size_t nBytes, uint flags); 679 static int raw_send(int fd, char* buf, size_t nBytes, uint flags); 680 static int timeout(int fd, long timeout); 681 static int listen(int fd, int count); 682 static int connect(int fd, struct sockaddr* him, socklen_t len); 683 static int bind(int fd, struct sockaddr* him, socklen_t len); 684 static int accept(int fd, struct sockaddr* him, socklen_t* len); 685 static int recvfrom(int fd, char* buf, size_t nbytes, uint flags, 686 struct sockaddr* from, socklen_t* fromlen); 687 static int get_sock_name(int fd, struct sockaddr* him, socklen_t* len); 688 static int sendto(int fd, char* buf, size_t len, uint flags, 689 struct sockaddr* to, socklen_t tolen); 690 static int socket_available(int fd, jint* pbytes); 691 692 static int get_sock_opt(int fd, int level, int optname, 693 char* optval, socklen_t* optlen); 694 static int set_sock_opt(int fd, int level, int optname, 695 const char* optval, socklen_t optlen); 696 static int get_host_name(char* name, int namelen); 697 698 static struct hostent* get_host_by_name(char* name); 699 700 // Support for signals (see JVM_RaiseSignal, JVM_RegisterSignal) 701 static void signal_init(); 702 static void signal_init_pd(); 703 static void signal_notify(int signal_number); 704 static void* signal(int signal_number, void* handler); 705 static void signal_raise(int signal_number); 706 static int signal_wait(); 707 static int signal_lookup(); 708 static void* user_handler(); 709 static void terminate_signal_thread(); 710 static int sigexitnum_pd(); 711 712 // random number generation 713 static long random(); // return 32bit pseudorandom number 714 static void init_random(long initval); // initialize random sequence 715 716 // Structured OS Exception support 717 static void os_exception_wrapper(java_call_t f, JavaValue* value, methodHandle* method, JavaCallArguments* args, Thread* thread); 718 719 // On Windows this will create an actual minidump, on Linux/Solaris it will simply check core dump limits 720 static void check_or_create_dump(void* exceptionRecord, void* contextRecord, char* buffer, size_t bufferSize); 721 722 // Get the default path to the core file 723 // Returns the length of the string 724 static int get_core_path(char* buffer, size_t bufferSize); 725 726 // JVMTI & JVM monitoring and management support 727 // The thread_cpu_time() and current_thread_cpu_time() are only 728 // supported if is_thread_cpu_time_supported() returns true. 729 // They are not supported on Solaris T1. 730 731 // Thread CPU Time - return the fast estimate on a platform 732 // On Solaris - call gethrvtime (fast) - user time only 733 // On Linux - fast clock_gettime where available - user+sys 734 // - otherwise: very slow /proc fs - user+sys 735 // On Windows - GetThreadTimes - user+sys 736 static jlong current_thread_cpu_time(); 737 static jlong thread_cpu_time(Thread* t); 738 739 // Thread CPU Time with user_sys_cpu_time parameter. 740 // 741 // If user_sys_cpu_time is true, user+sys time is returned. 742 // Otherwise, only user time is returned 743 static jlong current_thread_cpu_time(bool user_sys_cpu_time); 744 static jlong thread_cpu_time(Thread* t, bool user_sys_cpu_time); 745 746 // Return a bunch of info about the timers. 747 // Note that the returned info for these two functions may be different 748 // on some platforms 749 static void current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr); 750 static void thread_cpu_time_info(jvmtiTimerInfo *info_ptr); 751 752 static bool is_thread_cpu_time_supported(); 753 754 // System loadavg support. Returns -1 if load average cannot be obtained. 755 static int loadavg(double loadavg[], int nelem); 756 757 // Hook for os specific jvm options that we don't want to abort on seeing 758 static bool obsolete_option(const JavaVMOption *option); 759 760 // Extensions 761 #include "runtime/os_ext.hpp" 762 763 public: 764 class CrashProtectionCallback : public StackObj { 765 public: 766 virtual void call() = 0; 767 }; 768 769 // Platform dependent stuff 770 #ifdef TARGET_OS_FAMILY_linux 771 # include "os_linux.hpp" 772 # include "os_posix.hpp" 773 #endif 774 #ifdef TARGET_OS_FAMILY_solaris 775 # include "os_solaris.hpp" 776 # include "os_posix.hpp" 777 #endif 778 #ifdef TARGET_OS_FAMILY_windows 779 # include "os_windows.hpp" 780 #endif 781 #ifdef TARGET_OS_FAMILY_aix 782 # include "os_aix.hpp" 783 # include "os_posix.hpp" 784 #endif 785 #ifdef TARGET_OS_FAMILY_bsd 786 # include "os_posix.hpp" 787 # include "os_bsd.hpp" 788 #endif 789 #ifdef TARGET_OS_ARCH_linux_x86 790 # include "os_linux_x86.hpp" 791 #endif 792 #ifdef TARGET_OS_ARCH_linux_sparc 793 # include "os_linux_sparc.hpp" 794 #endif 795 #ifdef TARGET_OS_ARCH_linux_zero 796 # include "os_linux_zero.hpp" 797 #endif 798 #ifdef TARGET_OS_ARCH_solaris_x86 799 # include "os_solaris_x86.hpp" 800 #endif 801 #ifdef TARGET_OS_ARCH_solaris_sparc 802 # include "os_solaris_sparc.hpp" 803 #endif 804 #ifdef TARGET_OS_ARCH_windows_x86 805 # include "os_windows_x86.hpp" 806 #endif 807 #ifdef TARGET_OS_ARCH_linux_arm 808 # include "os_linux_arm.hpp" 809 #endif 810 #ifdef TARGET_OS_ARCH_linux_ppc 811 # include "os_linux_ppc.hpp" 812 #endif 813 #ifdef TARGET_OS_ARCH_aix_ppc 814 # include "os_aix_ppc.hpp" 815 #endif 816 #ifdef TARGET_OS_ARCH_bsd_x86 817 # include "os_bsd_x86.hpp" 818 #endif 819 #ifdef TARGET_OS_ARCH_bsd_zero 820 # include "os_bsd_zero.hpp" 821 #endif 822 823 #ifndef OS_NATIVE_THREAD_CREATION_FAILED_MSG 824 #define OS_NATIVE_THREAD_CREATION_FAILED_MSG "unable to create native thread: possibly out of memory or process/resource limits reached" 825 #endif 826 827 public: 828 #ifndef PLATFORM_PRINT_NATIVE_STACK 829 // No platform-specific code for printing the native stack. 830 static bool platform_print_native_stack(outputStream* st, void* context, 831 char *buf, int buf_size) { 832 return false; 833 } 834 #endif 835 836 // debugging support (mostly used by debug.cpp but also fatal error handler) 837 static bool find(address pc, outputStream* st = tty); // OS specific function to make sense out of an address 838 839 static bool dont_yield(); // when true, JVM_Yield() is nop 840 static void print_statistics(); 841 842 // Thread priority helpers (implemented in OS-specific part) 843 static OSReturn set_native_priority(Thread* thread, int native_prio); 844 static OSReturn get_native_priority(const Thread* const thread, int* priority_ptr); 845 static int java_to_os_priority[CriticalPriority + 1]; 846 // Hint to the underlying OS that a task switch would not be good. 847 // Void return because it's a hint and can fail. 848 static void hint_no_preempt(); 849 static const char* native_thread_creation_failed_msg() { 850 return OS_NATIVE_THREAD_CREATION_FAILED_MSG; 851 } 852 853 // Used at creation if requested by the diagnostic flag PauseAtStartup. 854 // Causes the VM to wait until an external stimulus has been applied 855 // (for Unix, that stimulus is a signal, for Windows, an external 856 // ResumeThread call) 857 static void pause(); 858 859 // Builds a platform dependent Agent_OnLoad_<libname> function name 860 // which is used to find statically linked in agents. 861 static char* build_agent_function_name(const char *sym, const char *cname, 862 bool is_absolute_path); 863 864 class SuspendedThreadTaskContext { 865 public: 866 SuspendedThreadTaskContext(Thread* thread, void *ucontext) : _thread(thread), _ucontext(ucontext) {} 867 Thread* thread() const { return _thread; } 868 void* ucontext() const { return _ucontext; } 869 private: 870 Thread* _thread; 871 void* _ucontext; 872 }; 873 874 class SuspendedThreadTask { 875 public: 876 SuspendedThreadTask(Thread* thread) : _thread(thread), _done(false) {} 877 virtual ~SuspendedThreadTask() {} 878 void run(); 879 bool is_done() { return _done; } 880 virtual void do_task(const SuspendedThreadTaskContext& context) = 0; 881 protected: 882 private: 883 void internal_do_task(); 884 Thread* _thread; 885 bool _done; 886 }; 887 888 #ifndef TARGET_OS_FAMILY_windows 889 // Suspend/resume support 890 // Protocol: 891 // 892 // a thread starts in SR_RUNNING 893 // 894 // SR_RUNNING can go to 895 // * SR_SUSPEND_REQUEST when the WatcherThread wants to suspend it 896 // SR_SUSPEND_REQUEST can go to 897 // * SR_RUNNING if WatcherThread decides it waited for SR_SUSPENDED too long (timeout) 898 // * SR_SUSPENDED if the stopped thread receives the signal and switches state 899 // SR_SUSPENDED can go to 900 // * SR_WAKEUP_REQUEST when the WatcherThread has done the work and wants to resume 901 // SR_WAKEUP_REQUEST can go to 902 // * SR_RUNNING when the stopped thread receives the signal 903 // * SR_WAKEUP_REQUEST on timeout (resend the signal and try again) 904 class SuspendResume { 905 public: 906 enum State { 907 SR_RUNNING, 908 SR_SUSPEND_REQUEST, 909 SR_SUSPENDED, 910 SR_WAKEUP_REQUEST 911 }; 912 913 private: 914 volatile State _state; 915 916 private: 917 /* try to switch state from state "from" to state "to" 918 * returns the state set after the method is complete 919 */ 920 State switch_state(State from, State to); 921 922 public: 923 SuspendResume() : _state(SR_RUNNING) { } 924 925 State state() const { return _state; } 926 927 State request_suspend() { 928 return switch_state(SR_RUNNING, SR_SUSPEND_REQUEST); 929 } 930 931 State cancel_suspend() { 932 return switch_state(SR_SUSPEND_REQUEST, SR_RUNNING); 933 } 934 935 State suspended() { 936 return switch_state(SR_SUSPEND_REQUEST, SR_SUSPENDED); 937 } 938 939 State request_wakeup() { 940 return switch_state(SR_SUSPENDED, SR_WAKEUP_REQUEST); 941 } 942 943 State running() { 944 return switch_state(SR_WAKEUP_REQUEST, SR_RUNNING); 945 } 946 947 bool is_running() const { 948 return _state == SR_RUNNING; 949 } 950 951 bool is_suspend_request() const { 952 return _state == SR_SUSPEND_REQUEST; 953 } 954 955 bool is_suspended() const { 956 return _state == SR_SUSPENDED; 957 } 958 }; 959 #endif 960 961 962 protected: 963 static long _rand_seed; // seed for random number generator 964 static int _processor_count; // number of processors 965 966 static char* format_boot_path(const char* format_string, 967 const char* home, 968 int home_len, 969 char fileSep, 970 char pathSep); 971 static bool set_boot_path(char fileSep, char pathSep); 972 static char** split_path(const char* path, int* n); 973 974 }; 975 976 // Note that "PAUSE" is almost always used with synchronization 977 // so arguably we should provide Atomic::SpinPause() instead 978 // of the global SpinPause() with C linkage. 979 // It'd also be eligible for inlining on many platforms. 980 981 extern "C" int SpinPause(); 982 983 #endif // SHARE_VM_RUNTIME_OS_HPP