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 # 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 template<class E> class GrowableArray; 70 71 // %%%%% Moved ThreadState, START_FN, OSThread to new osThread.hpp. -- Rose 72 73 // Platform-independent error return values from OS functions 74 enum OSReturn { 75 OS_OK = 0, // Operation was successful 76 OS_ERR = -1, // Operation failed 77 OS_INTRPT = -2, // Operation was interrupted 78 OS_TIMEOUT = -3, // Operation timed out 79 OS_NOMEM = -5, // Operation failed for lack of memory 80 OS_NORESOURCE = -6 // Operation failed for lack of nonmemory resource 81 }; 82 83 enum ThreadPriority { // JLS 20.20.1-3 84 NoPriority = -1, // Initial non-priority value 85 MinPriority = 1, // Minimum priority 86 NormPriority = 5, // Normal (non-daemon) priority 87 NearMaxPriority = 9, // High priority, used for VMThread 88 MaxPriority = 10, // Highest priority, used for WatcherThread 89 // ensures that VMThread doesn't starve profiler 90 CriticalPriority = 11 // Critical thread priority 91 }; 92 93 // Executable parameter flag for os::commit_memory() and 94 // os::commit_memory_or_exit(). 95 const bool ExecMem = true; 96 97 // Typedef for structured exception handling support 98 typedef void (*java_call_t)(JavaValue* value, methodHandle* method, JavaCallArguments* args, Thread* thread); 99 100 class os: AllStatic { 101 friend class VMStructs; 102 103 public: 104 enum { page_sizes_max = 9 }; // Size of _page_sizes array (8 plus a sentinel) 105 106 private: 107 static OSThread* _starting_thread; 108 static address _polling_page; 109 static volatile int32_t * _mem_serialize_page; 110 static uintptr_t _serialize_page_mask; 111 public: 112 static size_t _page_sizes[page_sizes_max]; 113 114 private: 115 static void init_page_sizes(size_t default_page_size) { 116 _page_sizes[0] = default_page_size; 117 _page_sizes[1] = 0; // sentinel 118 } 119 120 static char* pd_reserve_memory(size_t bytes, char* addr = 0, 121 size_t alignment_hint = 0); 122 static char* pd_attempt_reserve_memory_at(size_t bytes, char* addr); 123 static void pd_split_reserved_memory(char *base, size_t size, 124 size_t split, bool realloc); 125 static bool pd_commit_memory(char* addr, size_t bytes, bool executable); 126 static bool pd_commit_memory(char* addr, size_t size, size_t alignment_hint, 127 bool executable); 128 // Same as pd_commit_memory() that either succeeds or calls 129 // vm_exit_out_of_memory() with the specified mesg. 130 static void pd_commit_memory_or_exit(char* addr, size_t bytes, 131 bool executable, const char* mesg); 132 static void pd_commit_memory_or_exit(char* addr, size_t size, 133 size_t alignment_hint, 134 bool executable, const char* mesg); 135 static bool pd_uncommit_memory(char* addr, size_t bytes); 136 static bool pd_release_memory(char* addr, size_t bytes); 137 138 static char* pd_map_memory(int fd, const char* file_name, size_t file_offset, 139 char *addr, size_t bytes, bool read_only = false, 140 bool allow_exec = false); 141 static char* pd_remap_memory(int fd, const char* file_name, size_t file_offset, 142 char *addr, size_t bytes, bool read_only, 143 bool allow_exec); 144 static bool pd_unmap_memory(char *addr, size_t bytes); 145 static void pd_free_memory(char *addr, size_t bytes, size_t alignment_hint); 146 static void pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint); 147 148 149 public: 150 static void init(void); // Called before command line parsing 151 static void init_before_ergo(void); // Called after command line parsing 152 // before VM ergonomics processing. 153 static jint init_2(void); // Called after command line parsing 154 // and VM ergonomics processing 155 static void init_globals(void) { // Called from init_globals() in init.cpp 156 init_globals_ext(); 157 } 158 static void init_3(void); // Called at the end of vm init 159 160 // File names are case-insensitive on windows only 161 // Override me as needed 162 static int file_name_strcmp(const char* s1, const char* s2); 163 164 static bool getenv(const char* name, char* buffer, int len); 165 static bool have_special_privileges(); 166 167 static jlong javaTimeMillis(); 168 static jlong javaTimeNanos(); 169 static void javaTimeNanos_info(jvmtiTimerInfo *info_ptr); 170 static void run_periodic_checks(); 171 static bool supports_monotonic_clock(); 172 173 174 // Returns the elapsed time in seconds since the vm started. 175 static double elapsedTime(); 176 177 // Returns real time in seconds since an arbitrary point 178 // in the past. 179 static bool getTimesSecs(double* process_real_time, 180 double* process_user_time, 181 double* process_system_time); 182 183 // Interface to the performance counter 184 static jlong elapsed_counter(); 185 static jlong elapsed_frequency(); 186 187 // The "virtual time" of a thread is the amount of time a thread has 188 // actually run. The first function indicates whether the OS supports 189 // this functionality for the current thread, and if so: 190 // * the second enables vtime tracking (if that is required). 191 // * the third tells whether vtime is enabled. 192 // * the fourth returns the elapsed virtual time for the current 193 // thread. 194 static bool supports_vtime(); 195 static bool enable_vtime(); 196 static bool vtime_enabled(); 197 static double elapsedVTime(); 198 199 // Return current local time in a string (YYYY-MM-DD HH:MM:SS). 200 // It is MT safe, but not async-safe, as reading time zone 201 // information may require a lock on some platforms. 202 static char* local_time_string(char *buf, size_t buflen); 203 static struct tm* localtime_pd (const time_t* clock, struct tm* res); 204 // Fill in buffer with current local time as an ISO-8601 string. 205 // E.g., YYYY-MM-DDThh:mm:ss.mmm+zzzz. 206 // Returns buffer, or NULL if it failed. 207 static char* iso8601_time(char* buffer, size_t buffer_length); 208 209 // Interface for detecting multiprocessor system 210 static inline bool is_MP() { 211 assert(_processor_count > 0, "invalid processor count"); 212 return _processor_count > 1 || AssumeMP; 213 } 214 static julong available_memory(); 215 static julong physical_memory(); 216 static bool has_allocatable_memory_limit(julong* limit); 217 static bool is_server_class_machine(); 218 219 // number of CPUs 220 static int processor_count() { 221 return _processor_count; 222 } 223 static void set_processor_count(int count) { _processor_count = count; } 224 225 // Returns the number of CPUs this process is currently allowed to run on. 226 // Note that on some OSes this can change dynamically. 227 static int active_processor_count(); 228 229 // Bind processes to processors. 230 // This is a two step procedure: 231 // first you generate a distribution of processes to processors, 232 // then you bind processes according to that distribution. 233 // Compute a distribution for number of processes to processors. 234 // Stores the processor id's into the distribution array argument. 235 // Returns true if it worked, false if it didn't. 236 static bool distribute_processes(uint length, uint* distribution); 237 // Binds the current process to a processor. 238 // Returns true if it worked, false if it didn't. 239 static bool bind_to_processor(uint processor_id); 240 241 // Give a name to the current thread. 242 static void set_native_thread_name(const char *name); 243 244 // Interface for stack banging (predetect possible stack overflow for 245 // exception processing) There are guard pages, and above that shadow 246 // pages for stack overflow checking. 247 static bool uses_stack_guard_pages(); 248 static bool allocate_stack_guard_pages(); 249 static void bang_stack_shadow_pages(); 250 static bool stack_shadow_pages_available(Thread *thread, methodHandle method); 251 252 // OS interface to Virtual Memory 253 254 // Return the default page size. 255 static int vm_page_size(); 256 257 // Return the page size to use for a region of memory. The min_pages argument 258 // is a hint intended to limit fragmentation; it says the returned page size 259 // should be <= region_max_size / min_pages. Because min_pages is a hint, 260 // this routine may return a size larger than region_max_size / min_pages. 261 // 262 // The current implementation ignores min_pages if a larger page size is an 263 // exact multiple of both region_min_size and region_max_size. This allows 264 // larger pages to be used when doing so would not cause fragmentation; in 265 // particular, a single page can be used when region_min_size == 266 // region_max_size == a supported page size. 267 static size_t page_size_for_region(size_t region_min_size, 268 size_t region_max_size, 269 uint min_pages); 270 // Return the largest page size that can be used 271 static size_t max_page_size() { 272 // The _page_sizes array is sorted in descending order. 273 return _page_sizes[0]; 274 } 275 276 // Methods for tracing page sizes returned by the above method; enabled by 277 // TracePageSizes. The region_{min,max}_size parameters should be the values 278 // passed to page_size_for_region() and page_size should be the result of that 279 // call. The (optional) base and size parameters should come from the 280 // ReservedSpace base() and size() methods. 281 static void trace_page_sizes(const char* str, const size_t* page_sizes, 282 int count) PRODUCT_RETURN; 283 static void trace_page_sizes(const char* str, const size_t region_min_size, 284 const size_t region_max_size, 285 const size_t page_size, 286 const char* base = NULL, 287 const size_t size = 0) PRODUCT_RETURN; 288 289 static int vm_allocation_granularity(); 290 static char* reserve_memory(size_t bytes, char* addr = 0, 291 size_t alignment_hint = 0); 292 static char* reserve_memory(size_t bytes, char* addr, 293 size_t alignment_hint, MEMFLAGS flags); 294 static char* reserve_memory_aligned(size_t size, size_t alignment); 295 static char* attempt_reserve_memory_at(size_t bytes, char* addr); 296 static void split_reserved_memory(char *base, size_t size, 297 size_t split, bool realloc); 298 static bool commit_memory(char* addr, size_t bytes, bool executable); 299 static bool commit_memory(char* addr, size_t size, size_t alignment_hint, 300 bool executable); 301 // Same as commit_memory() that either succeeds or calls 302 // vm_exit_out_of_memory() with the specified mesg. 303 static void commit_memory_or_exit(char* addr, size_t bytes, 304 bool executable, const char* mesg); 305 static void commit_memory_or_exit(char* addr, size_t size, 306 size_t alignment_hint, 307 bool executable, const char* mesg); 308 static bool uncommit_memory(char* addr, size_t bytes); 309 static bool release_memory(char* addr, size_t bytes); 310 311 enum ProtType { MEM_PROT_NONE, MEM_PROT_READ, MEM_PROT_RW, MEM_PROT_RWX }; 312 static bool protect_memory(char* addr, size_t bytes, ProtType prot, 313 bool is_committed = true); 314 315 static bool guard_memory(char* addr, size_t bytes); 316 static bool unguard_memory(char* addr, size_t bytes); 317 static bool create_stack_guard_pages(char* addr, size_t bytes); 318 static bool pd_create_stack_guard_pages(char* addr, size_t bytes); 319 static bool remove_stack_guard_pages(char* addr, size_t bytes); 320 321 static char* map_memory(int fd, const char* file_name, size_t file_offset, 322 char *addr, size_t bytes, bool read_only = false, 323 bool allow_exec = false); 324 static char* remap_memory(int fd, const char* file_name, size_t file_offset, 325 char *addr, size_t bytes, bool read_only, 326 bool allow_exec); 327 static bool unmap_memory(char *addr, size_t bytes); 328 static void free_memory(char *addr, size_t bytes, size_t alignment_hint); 329 static void realign_memory(char *addr, size_t bytes, size_t alignment_hint); 330 331 // NUMA-specific interface 332 static bool numa_has_static_binding(); 333 static bool numa_has_group_homing(); 334 static void numa_make_local(char *addr, size_t bytes, int lgrp_hint); 335 static void numa_make_global(char *addr, size_t bytes); 336 static size_t numa_get_groups_num(); 337 static size_t numa_get_leaf_groups(int *ids, size_t size); 338 static bool numa_topology_changed(); 339 static int numa_get_group_id(); 340 341 // Page manipulation 342 struct page_info { 343 size_t size; 344 int lgrp_id; 345 }; 346 static bool get_page_info(char *start, page_info* info); 347 static char* scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found); 348 349 static char* non_memory_address_word(); 350 // reserve, commit and pin the entire memory region 351 static char* reserve_memory_special(size_t size, size_t alignment, 352 char* addr, bool executable); 353 static bool release_memory_special(char* addr, size_t bytes); 354 static void large_page_init(); 355 static size_t large_page_size(); 356 static bool can_commit_large_page_memory(); 357 static bool can_execute_large_page_memory(); 358 359 // OS interface to polling page 360 static address get_polling_page() { return _polling_page; } 361 static void set_polling_page(address page) { _polling_page = page; } 362 static bool is_poll_address(address addr) { return addr >= _polling_page && addr < (_polling_page + os::vm_page_size()); } 363 static void make_polling_page_unreadable(); 364 static void make_polling_page_readable(); 365 366 // Routines used to serialize the thread state without using membars 367 static void serialize_thread_states(); 368 369 // Since we write to the serialize page from every thread, we 370 // want stores to be on unique cache lines whenever possible 371 // in order to minimize CPU cross talk. We pre-compute the 372 // amount to shift the thread* to make this offset unique to 373 // each thread. 374 static int get_serialize_page_shift_count() { 375 return SerializePageShiftCount; 376 } 377 378 static void set_serialize_page_mask(uintptr_t mask) { 379 _serialize_page_mask = mask; 380 } 381 382 static unsigned int get_serialize_page_mask() { 383 return _serialize_page_mask; 384 } 385 386 static void set_memory_serialize_page(address page); 387 388 static address get_memory_serialize_page() { 389 return (address)_mem_serialize_page; 390 } 391 392 static inline void write_memory_serialize_page(JavaThread *thread) { 393 uintptr_t page_offset = ((uintptr_t)thread >> 394 get_serialize_page_shift_count()) & 395 get_serialize_page_mask(); 396 *(volatile int32_t *)((uintptr_t)_mem_serialize_page+page_offset) = 1; 397 } 398 399 static bool is_memory_serialize_page(JavaThread *thread, address addr) { 400 if (UseMembar) return false; 401 // Previously this function calculated the exact address of this 402 // thread's serialize page, and checked if the faulting address 403 // was equal. However, some platforms mask off faulting addresses 404 // to the page size, so now we just check that the address is 405 // within the page. This makes the thread argument unnecessary, 406 // but we retain the NULL check to preserve existing behavior. 407 if (thread == NULL) return false; 408 address page = (address) _mem_serialize_page; 409 return addr >= page && addr < (page + os::vm_page_size()); 410 } 411 412 static void block_on_serialize_page_trap(); 413 414 // threads 415 416 enum ThreadType { 417 vm_thread, 418 cgc_thread, // Concurrent GC thread 419 pgc_thread, // Parallel GC thread 420 java_thread, 421 compiler_thread, 422 watcher_thread, 423 os_thread 424 }; 425 426 static bool create_thread(Thread* thread, 427 ThreadType thr_type, 428 size_t stack_size = 0); 429 static bool create_main_thread(JavaThread* thread); 430 static bool create_attached_thread(JavaThread* thread); 431 static void pd_start_thread(Thread* thread); 432 static void start_thread(Thread* thread); 433 434 static void initialize_thread(Thread* thr); 435 static void free_thread(OSThread* osthread); 436 437 // thread id on Linux/64bit is 64bit, on Windows and Solaris, it's 32bit 438 static intx current_thread_id(); 439 static int current_process_id(); 440 static int sleep(Thread* thread, jlong ms, bool interruptable); 441 // Short standalone OS sleep suitable for slow path spin loop. 442 // Ignores Thread.interrupt() (so keep it short). 443 // ms = 0, will sleep for the least amount of time allowed by the OS. 444 static void naked_short_sleep(jlong ms); 445 static void infinite_sleep(); // never returns, use with CAUTION 446 static void yield(); // Yields to all threads with same priority 447 enum YieldResult { 448 YIELD_SWITCHED = 1, // caller descheduled, other ready threads exist & ran 449 YIELD_NONEREADY = 0, // No other runnable/ready threads. 450 // platform-specific yield return immediately 451 YIELD_UNKNOWN = -1 // Unknown: platform doesn't support _SWITCHED or _NONEREADY 452 // YIELD_SWITCHED and YIELD_NONREADY imply the platform supports a "strong" 453 // yield that can be used in lieu of blocking. 454 } ; 455 static YieldResult NakedYield () ; 456 static void yield_all(); // Yields to all other threads including lower priority 457 // (for the default scheduling policy) 458 static OSReturn set_priority(Thread* thread, ThreadPriority priority); 459 static OSReturn get_priority(const Thread* const thread, ThreadPriority& priority); 460 461 static void interrupt(Thread* thread); 462 static bool is_interrupted(Thread* thread, bool clear_interrupted); 463 464 static int pd_self_suspend_thread(Thread* thread); 465 466 static ExtendedPC fetch_frame_from_context(void* ucVoid, intptr_t** sp, intptr_t** fp); 467 static frame fetch_frame_from_context(void* ucVoid); 468 469 static ExtendedPC get_thread_pc(Thread *thread); 470 static void breakpoint(); 471 472 static address current_stack_pointer(); 473 static address current_stack_base(); 474 static size_t current_stack_size(); 475 476 static void verify_stack_alignment() PRODUCT_RETURN; 477 478 static int message_box(const char* title, const char* message); 479 static char* do_you_want_to_debug(const char* message); 480 481 // run cmd in a separate process and return its exit code; or -1 on failures 482 static int fork_and_exec(char *cmd); 483 484 // Set file to send error reports. 485 static void set_error_file(const char *logfile); 486 487 // os::exit() is merged with vm_exit() 488 // static void exit(int num); 489 490 // Terminate the VM, but don't exit the process 491 static void shutdown(); 492 493 // Terminate with an error. Default is to generate a core file on platforms 494 // that support such things. This calls shutdown() and then aborts. 495 static void abort(bool dump_core = true); 496 497 // Die immediately, no exit hook, no abort hook, no cleanup. 498 static void die(); 499 500 // File i/o operations 501 static const int default_file_open_flags(); 502 static int open(const char *path, int oflag, int mode); 503 static FILE* open(int fd, const char* mode); 504 static int close(int fd); 505 static jlong lseek(int fd, jlong offset, int whence); 506 static char* native_path(char *path); 507 static int ftruncate(int fd, jlong length); 508 static int fsync(int fd); 509 static int available(int fd, jlong *bytes); 510 511 //File i/o operations 512 513 static size_t read(int fd, void *buf, unsigned int nBytes); 514 static size_t restartable_read(int fd, void *buf, unsigned int nBytes); 515 static size_t write(int fd, const void *buf, unsigned int nBytes); 516 517 // Reading directories. 518 static DIR* opendir(const char* dirname); 519 static int readdir_buf_size(const char *path); 520 static struct dirent* readdir(DIR* dirp, dirent* dbuf); 521 static int closedir(DIR* dirp); 522 523 // Dynamic library extension 524 static const char* dll_file_extension(); 525 526 static const char* get_temp_directory(); 527 static const char* get_current_directory(char *buf, size_t buflen); 528 529 // Builds a platform-specific full library path given a ld path and lib name 530 // Returns true if buffer contains full path to existing file, false otherwise 531 static bool dll_build_name(char* buffer, size_t size, 532 const char* pathname, const char* fname); 533 534 // Symbol lookup, find nearest function name; basically it implements 535 // dladdr() for all platforms. Name of the nearest function is copied 536 // to buf. Distance from its base address is optionally returned as offset. 537 // If function name is not found, buf[0] is set to '\0' and offset is 538 // set to -1 (if offset is non-NULL). 539 static bool dll_address_to_function_name(address addr, char* buf, 540 int buflen, int* offset); 541 542 // Locate DLL/DSO. On success, full path of the library is copied to 543 // buf, and offset is optionally set to be the distance between addr 544 // and the library's base address. On failure, buf[0] is set to '\0' 545 // and offset is set to -1 (if offset is non-NULL). 546 static bool dll_address_to_library_name(address addr, char* buf, 547 int buflen, int* offset); 548 549 // Find out whether the pc is in the static code for jvm.dll/libjvm.so. 550 static bool address_is_in_vm(address addr); 551 552 // Loads .dll/.so and 553 // in case of error it checks if .dll/.so was built for the 554 // same architecture as HotSpot is running on 555 static void* dll_load(const char *name, char *ebuf, int ebuflen); 556 557 // lookup symbol in a shared library 558 static void* dll_lookup(void* handle, const char* name); 559 560 // Unload library 561 static void dll_unload(void *lib); 562 563 // Return the handle of this process 564 static void* get_default_process_handle(); 565 566 // Check for static linked agent library 567 static bool find_builtin_agent(AgentLibrary *agent_lib, const char *syms[], 568 size_t syms_len); 569 570 // Find agent entry point 571 static void *find_agent_function(AgentLibrary *agent_lib, bool check_lib, 572 const char *syms[], size_t syms_len); 573 574 // Print out system information; they are called by fatal error handler. 575 // Output format may be different on different platforms. 576 static void print_os_info(outputStream* st); 577 static void print_os_info_brief(outputStream* st); 578 static void print_cpu_info(outputStream* st); 579 static void pd_print_cpu_info(outputStream* st); 580 static void print_memory_info(outputStream* st); 581 static void print_dll_info(outputStream* st); 582 static void print_environment_variables(outputStream* st, const char** env_list, char* buffer, int len); 583 static void print_context(outputStream* st, void* context); 584 static void print_register_info(outputStream* st, void* context); 585 static void print_siginfo(outputStream* st, void* siginfo); 586 static void print_signal_handlers(outputStream* st, char* buf, size_t buflen); 587 static void print_date_and_time(outputStream* st); 588 589 static void print_location(outputStream* st, intptr_t x, bool verbose = false); 590 static size_t lasterror(char *buf, size_t len); 591 static int get_last_error(); 592 593 // Determines whether the calling process is being debugged by a user-mode debugger. 594 static bool is_debugger_attached(); 595 596 // wait for a key press if PauseAtExit is set 597 static void wait_for_keypress_at_exit(void); 598 599 // The following two functions are used by fatal error handler to trace 600 // native (C) frames. They are not part of frame.hpp/frame.cpp because 601 // frame.hpp/cpp assume thread is JavaThread, and also because different 602 // OS/compiler may have different convention or provide different API to 603 // walk C frames. 604 // 605 // We don't attempt to become a debugger, so we only follow frames if that 606 // does not require a lookup in the unwind table, which is part of the binary 607 // file but may be unsafe to read after a fatal error. So on x86, we can 608 // only walk stack if %ebp is used as frame pointer; on ia64, it's not 609 // possible to walk C stack without having the unwind table. 610 static bool is_first_C_frame(frame *fr); 611 static frame get_sender_for_C_frame(frame *fr); 612 613 // return current frame. pc() and sp() are set to NULL on failure. 614 static frame current_frame(); 615 616 static void print_hex_dump(outputStream* st, address start, address end, int unitsize); 617 618 // returns a string to describe the exception/signal; 619 // returns NULL if exception_code is not an OS exception/signal. 620 static const char* exception_name(int exception_code, char* buf, size_t buflen); 621 622 // Returns native Java library, loads if necessary 623 static void* native_java_library(); 624 625 // Fills in path to jvm.dll/libjvm.so (used by the Disassembler) 626 static void jvm_path(char *buf, jint buflen); 627 628 // Returns true if we are running in a headless jre. 629 static bool is_headless_jre(); 630 631 // JNI names 632 static void print_jni_name_prefix_on(outputStream* st, int args_size); 633 static void print_jni_name_suffix_on(outputStream* st, int args_size); 634 635 // File conventions 636 static const char* file_separator(); 637 static const char* line_separator(); 638 static const char* path_separator(); 639 640 // Init os specific system properties values 641 static void init_system_properties_values(); 642 643 // IO operations, non-JVM_ version. 644 static int stat(const char* path, struct stat* sbuf); 645 static bool dir_is_empty(const char* path); 646 647 // IO operations on binary files 648 static int create_binary_file(const char* path, bool rewrite_existing); 649 static jlong current_file_offset(int fd); 650 static jlong seek_to_file_offset(int fd, jlong offset); 651 652 // Thread Local Storage 653 static int allocate_thread_local_storage(); 654 static void thread_local_storage_at_put(int index, void* value); 655 static void* thread_local_storage_at(int index); 656 static void free_thread_local_storage(int index); 657 658 // Stack walk 659 static address get_caller_pc(int n = 0); 660 661 // General allocation (must be MT-safe) 662 static void* malloc (size_t size, MEMFLAGS flags, address caller_pc = 0); 663 static void* realloc (void *memblock, size_t size, MEMFLAGS flags, address caller_pc = 0); 664 static void free (void *memblock, MEMFLAGS flags = mtNone); 665 static bool check_heap(bool force = false); // verify C heap integrity 666 static char* strdup(const char *, MEMFLAGS flags = mtInternal); // Like strdup 667 668 #ifndef PRODUCT 669 static julong num_mallocs; // # of calls to malloc/realloc 670 static julong alloc_bytes; // # of bytes allocated 671 static julong num_frees; // # of calls to free 672 static julong free_bytes; // # of bytes freed 673 #endif 674 675 // SocketInterface (ex HPI SocketInterface ) 676 static int socket(int domain, int type, int protocol); 677 static int socket_close(int fd); 678 static int socket_shutdown(int fd, int howto); 679 static int recv(int fd, char* buf, size_t nBytes, uint flags); 680 static int send(int fd, char* buf, size_t nBytes, uint flags); 681 static int raw_send(int fd, char* buf, size_t nBytes, uint flags); 682 static int timeout(int fd, long timeout); 683 static int listen(int fd, int count); 684 static int connect(int fd, struct sockaddr* him, socklen_t len); 685 static int bind(int fd, struct sockaddr* him, socklen_t len); 686 static int accept(int fd, struct sockaddr* him, socklen_t* len); 687 static int recvfrom(int fd, char* buf, size_t nbytes, uint flags, 688 struct sockaddr* from, socklen_t* fromlen); 689 static int get_sock_name(int fd, struct sockaddr* him, socklen_t* len); 690 static int sendto(int fd, char* buf, size_t len, uint flags, 691 struct sockaddr* to, socklen_t tolen); 692 static int socket_available(int fd, jint* pbytes); 693 694 static int get_sock_opt(int fd, int level, int optname, 695 char* optval, socklen_t* optlen); 696 static int set_sock_opt(int fd, int level, int optname, 697 const char* optval, socklen_t optlen); 698 static int get_host_name(char* name, int namelen); 699 700 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 Windows this will create an actual minidump, on Linux/Solaris it will simply check core dump limits 722 static void check_or_create_dump(void* exceptionRecord, void* contextRecord, char* buffer, size_t bufferSize); 723 724 // Get the default path to the core file 725 // Returns the length of the string 726 static int get_core_path(char* buffer, size_t bufferSize); 727 728 // JVMTI & JVM monitoring and management support 729 // The thread_cpu_time() and current_thread_cpu_time() are only 730 // supported if is_thread_cpu_time_supported() returns true. 731 // They are not supported on Solaris T1. 732 733 // Thread CPU Time - return the fast estimate on a platform 734 // On Solaris - call gethrvtime (fast) - user time only 735 // On Linux - fast clock_gettime where available - user+sys 736 // - otherwise: very slow /proc fs - user+sys 737 // On Windows - GetThreadTimes - user+sys 738 static jlong current_thread_cpu_time(); 739 static jlong thread_cpu_time(Thread* t); 740 741 // Thread CPU Time with user_sys_cpu_time parameter. 742 // 743 // If user_sys_cpu_time is true, user+sys time is returned. 744 // Otherwise, only user time is returned 745 static jlong current_thread_cpu_time(bool user_sys_cpu_time); 746 static jlong thread_cpu_time(Thread* t, bool user_sys_cpu_time); 747 748 // Return a bunch of info about the timers. 749 // Note that the returned info for these two functions may be different 750 // on some platforms 751 static void current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr); 752 static void thread_cpu_time_info(jvmtiTimerInfo *info_ptr); 753 754 static bool is_thread_cpu_time_supported(); 755 756 // System loadavg support. Returns -1 if load average cannot be obtained. 757 static int loadavg(double loadavg[], int nelem); 758 759 // Hook for os specific jvm options that we don't want to abort on seeing 760 static bool obsolete_option(const JavaVMOption *option); 761 762 // Extensions 763 #include "runtime/os_ext.hpp" 764 765 public: 766 class CrashProtectionCallback : public StackObj { 767 public: 768 virtual void call() = 0; 769 }; 770 771 // Platform dependent stuff 772 #ifdef TARGET_OS_FAMILY_linux 773 # include "os_linux.hpp" 774 # include "os_posix.hpp" 775 #endif 776 #ifdef TARGET_OS_FAMILY_solaris 777 # include "os_solaris.hpp" 778 # include "os_posix.hpp" 779 #endif 780 #ifdef TARGET_OS_FAMILY_windows 781 # include "os_windows.hpp" 782 #endif 783 #ifdef TARGET_OS_FAMILY_aix 784 # include "os_aix.hpp" 785 # include "os_posix.hpp" 786 #endif 787 #ifdef TARGET_OS_FAMILY_bsd 788 # include "os_posix.hpp" 789 # include "os_bsd.hpp" 790 #endif 791 #ifdef TARGET_OS_ARCH_linux_x86 792 # include "os_linux_x86.hpp" 793 #endif 794 #ifdef TARGET_OS_ARCH_linux_sparc 795 # include "os_linux_sparc.hpp" 796 #endif 797 #ifdef TARGET_OS_ARCH_linux_zero 798 # include "os_linux_zero.hpp" 799 #endif 800 #ifdef TARGET_OS_ARCH_solaris_x86 801 # include "os_solaris_x86.hpp" 802 #endif 803 #ifdef TARGET_OS_ARCH_solaris_sparc 804 # include "os_solaris_sparc.hpp" 805 #endif 806 #ifdef TARGET_OS_ARCH_windows_x86 807 # include "os_windows_x86.hpp" 808 #endif 809 #ifdef TARGET_OS_ARCH_linux_arm 810 # include "os_linux_arm.hpp" 811 #endif 812 #ifdef TARGET_OS_ARCH_linux_ppc 813 # include "os_linux_ppc.hpp" 814 #endif 815 #ifdef TARGET_OS_ARCH_aix_ppc 816 # include "os_aix_ppc.hpp" 817 #endif 818 #ifdef TARGET_OS_ARCH_bsd_x86 819 # include "os_bsd_x86.hpp" 820 #endif 821 #ifdef TARGET_OS_ARCH_bsd_zero 822 # include "os_bsd_zero.hpp" 823 #endif 824 825 #ifndef OS_NATIVE_THREAD_CREATION_FAILED_MSG 826 #define OS_NATIVE_THREAD_CREATION_FAILED_MSG "unable to create native thread: possibly out of memory or process/resource limits reached" 827 #endif 828 829 public: 830 #ifndef PLATFORM_PRINT_NATIVE_STACK 831 // No platform-specific code for printing the native stack. 832 static bool platform_print_native_stack(outputStream* st, void* context, 833 char *buf, int buf_size) { 834 return false; 835 } 836 #endif 837 838 // debugging support (mostly used by debug.cpp but also fatal error handler) 839 static bool find(address pc, outputStream* st = tty); // OS specific function to make sense out of an address 840 841 static bool dont_yield(); // when true, JVM_Yield() is nop 842 static void print_statistics(); 843 844 // Thread priority helpers (implemented in OS-specific part) 845 static OSReturn set_native_priority(Thread* thread, int native_prio); 846 static OSReturn get_native_priority(const Thread* const thread, int* priority_ptr); 847 static int java_to_os_priority[CriticalPriority + 1]; 848 // Hint to the underlying OS that a task switch would not be good. 849 // Void return because it's a hint and can fail. 850 static void hint_no_preempt(); 851 static const char* native_thread_creation_failed_msg() { 852 return OS_NATIVE_THREAD_CREATION_FAILED_MSG; 853 } 854 855 // Used at creation if requested by the diagnostic flag PauseAtStartup. 856 // Causes the VM to wait until an external stimulus has been applied 857 // (for Unix, that stimulus is a signal, for Windows, an external 858 // ResumeThread call) 859 static void pause(); 860 861 // Builds a platform dependent Agent_OnLoad_<libname> function name 862 // which is used to find statically linked in agents. 863 static char* build_agent_function_name(const char *sym, const char *cname, 864 bool is_absolute_path); 865 866 class SuspendedThreadTaskContext { 867 public: 868 SuspendedThreadTaskContext(Thread* thread, void *ucontext) : _thread(thread), _ucontext(ucontext) {} 869 Thread* thread() const { return _thread; } 870 void* ucontext() const { return _ucontext; } 871 private: 872 Thread* _thread; 873 void* _ucontext; 874 }; 875 876 class SuspendedThreadTask { 877 public: 878 SuspendedThreadTask(Thread* thread) : _thread(thread), _done(false) {} 879 virtual ~SuspendedThreadTask() {} 880 void run(); 881 bool is_done() { return _done; } 882 virtual void do_task(const SuspendedThreadTaskContext& context) = 0; 883 protected: 884 private: 885 void internal_do_task(); 886 Thread* _thread; 887 bool _done; 888 }; 889 890 #ifndef TARGET_OS_FAMILY_windows 891 // Suspend/resume support 892 // Protocol: 893 // 894 // a thread starts in SR_RUNNING 895 // 896 // SR_RUNNING can go to 897 // * SR_SUSPEND_REQUEST when the WatcherThread wants to suspend it 898 // SR_SUSPEND_REQUEST can go to 899 // * SR_RUNNING if WatcherThread decides it waited for SR_SUSPENDED too long (timeout) 900 // * SR_SUSPENDED if the stopped thread receives the signal and switches state 901 // SR_SUSPENDED can go to 902 // * SR_WAKEUP_REQUEST when the WatcherThread has done the work and wants to resume 903 // SR_WAKEUP_REQUEST can go to 904 // * SR_RUNNING when the stopped thread receives the signal 905 // * SR_WAKEUP_REQUEST on timeout (resend the signal and try again) 906 class SuspendResume { 907 public: 908 enum State { 909 SR_RUNNING, 910 SR_SUSPEND_REQUEST, 911 SR_SUSPENDED, 912 SR_WAKEUP_REQUEST 913 }; 914 915 private: 916 volatile State _state; 917 918 private: 919 /* try to switch state from state "from" to state "to" 920 * returns the state set after the method is complete 921 */ 922 State switch_state(State from, State to); 923 924 public: 925 SuspendResume() : _state(SR_RUNNING) { } 926 927 State state() const { return _state; } 928 929 State request_suspend() { 930 return switch_state(SR_RUNNING, SR_SUSPEND_REQUEST); 931 } 932 933 State cancel_suspend() { 934 return switch_state(SR_SUSPEND_REQUEST, SR_RUNNING); 935 } 936 937 State suspended() { 938 return switch_state(SR_SUSPEND_REQUEST, SR_SUSPENDED); 939 } 940 941 State request_wakeup() { 942 return switch_state(SR_SUSPENDED, SR_WAKEUP_REQUEST); 943 } 944 945 State running() { 946 return switch_state(SR_WAKEUP_REQUEST, SR_RUNNING); 947 } 948 949 bool is_running() const { 950 return _state == SR_RUNNING; 951 } 952 953 bool is_suspend_request() const { 954 return _state == SR_SUSPEND_REQUEST; 955 } 956 957 bool is_suspended() const { 958 return _state == SR_SUSPENDED; 959 } 960 }; 961 #endif 962 963 964 protected: 965 static long _rand_seed; // seed for random number generator 966 static int _processor_count; // number of processors 967 968 static char* format_boot_path(const char* format_string, 969 const char* home, 970 int home_len, 971 char fileSep, 972 char pathSep); 973 static bool set_boot_path(char fileSep, char pathSep); 974 static char** split_path(const char* path, int* n); 975 976 }; 977 978 // Note that "PAUSE" is almost always used with synchronization 979 // so arguably we should provide Atomic::SpinPause() instead 980 // of the global SpinPause() with C linkage. 981 // It'd also be eligible for inlining on many platforms. 982 983 extern "C" int SpinPause(); 984 985 #endif // SHARE_VM_RUNTIME_OS_HPP