os.hpp revision 6646:b596a1063e90
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 55class 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 61typedef void (*dll_func)(...); 62 63class Thread; 64class JavaThread; 65class Event; 66class DLL; 67class FileHandle; 68template<class E> class GrowableArray; 69 70// %%%%% Moved ThreadState, START_FN, OSThread to new osThread.hpp. -- Rose 71 72// Platform-independent error return values from OS functions 73enum OSReturn { 74 OS_OK = 0, // Operation was successful 75 OS_ERR = -1, // Operation failed 76 OS_INTRPT = -2, // Operation was interrupted 77 OS_TIMEOUT = -3, // Operation timed out 78 OS_NOMEM = -5, // Operation failed for lack of memory 79 OS_NORESOURCE = -6 // Operation failed for lack of nonmemory resource 80}; 81 82enum ThreadPriority { // JLS 20.20.1-3 83 NoPriority = -1, // Initial non-priority value 84 MinPriority = 1, // Minimum priority 85 NormPriority = 5, // Normal (non-daemon) priority 86 NearMaxPriority = 9, // High priority, used for VMThread 87 MaxPriority = 10, // Highest priority, used for WatcherThread 88 // ensures that VMThread doesn't starve profiler 89 CriticalPriority = 11 // Critical thread priority 90}; 91 92// Executable parameter flag for os::commit_memory() and 93// os::commit_memory_or_exit(). 94const bool ExecMem = true; 95 96// Typedef for structured exception handling support 97typedef void (*java_call_t)(JavaValue* value, methodHandle* method, JavaCallArguments* args, Thread* thread); 98 99class os: AllStatic { 100 friend class VMStructs; 101 102 public: 103 enum { page_sizes_max = 9 }; // Size of _page_sizes array (8 plus a sentinel) 104 105 private: 106 static OSThread* _starting_thread; 107 static address _polling_page; 108 static volatile int32_t * _mem_serialize_page; 109 static uintptr_t _serialize_page_mask; 110 public: 111 static size_t _page_sizes[page_sizes_max]; 112 113 private: 114 static void init_page_sizes(size_t default_page_size) { 115 _page_sizes[0] = default_page_size; 116 _page_sizes[1] = 0; // sentinel 117 } 118 119 static char* pd_reserve_memory(size_t bytes, char* addr = 0, 120 size_t alignment_hint = 0); 121 static char* pd_attempt_reserve_memory_at(size_t bytes, char* addr); 122 static void pd_split_reserved_memory(char *base, size_t size, 123 size_t split, bool realloc); 124 static bool pd_commit_memory(char* addr, size_t bytes, bool executable); 125 static bool pd_commit_memory(char* addr, size_t size, size_t alignment_hint, 126 bool executable); 127 // Same as pd_commit_memory() that either succeeds or calls 128 // vm_exit_out_of_memory() with the specified mesg. 129 static void pd_commit_memory_or_exit(char* addr, size_t bytes, 130 bool executable, const char* mesg); 131 static void pd_commit_memory_or_exit(char* addr, size_t size, 132 size_t alignment_hint, 133 bool executable, const char* mesg); 134 static bool pd_uncommit_memory(char* addr, size_t bytes); 135 static bool pd_release_memory(char* addr, size_t bytes); 136 137 static char* pd_map_memory(int fd, const char* file_name, size_t file_offset, 138 char *addr, size_t bytes, bool read_only = false, 139 bool allow_exec = false); 140 static char* pd_remap_memory(int fd, const char* file_name, size_t file_offset, 141 char *addr, size_t bytes, bool read_only, 142 bool allow_exec); 143 static bool pd_unmap_memory(char *addr, size_t bytes); 144 static void pd_free_memory(char *addr, size_t bytes, size_t alignment_hint); 145 static void pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint); 146 147 148 public: 149 static void init(void); // Called before command line parsing 150 static void init_before_ergo(void); // Called after command line parsing 151 // before VM ergonomics processing. 152 static jint init_2(void); // Called after command line parsing 153 // and VM ergonomics processing 154 static void init_globals(void) { // Called from init_globals() in init.cpp 155 init_globals_ext(); 156 } 157 static void init_3(void); // Called at the end of vm init 158 159 // File names are case-insensitive on windows only 160 // Override me as needed 161 static int file_name_strcmp(const char* s1, const char* s2); 162 163 static bool getenv(const char* name, char* buffer, int len); 164 static bool have_special_privileges(); 165 166 static jlong javaTimeMillis(); 167 static jlong javaTimeNanos(); 168 static void javaTimeNanos_info(jvmtiTimerInfo *info_ptr); 169 static void run_periodic_checks(); 170 static bool supports_monotonic_clock(); 171 172 173 // Returns the elapsed time in seconds since the vm started. 174 static double elapsedTime(); 175 176 // Returns real time in seconds since an arbitrary point 177 // in the past. 178 static bool getTimesSecs(double* process_real_time, 179 double* process_user_time, 180 double* process_system_time); 181 182 // Interface to the performance counter 183 static jlong elapsed_counter(); 184 static jlong elapsed_frequency(); 185 186 // The "virtual time" of a thread is the amount of time a thread has 187 // actually run. The first function indicates whether the OS supports 188 // this functionality for the current thread, and if so: 189 // * the second enables vtime tracking (if that is required). 190 // * the third tells whether vtime is enabled. 191 // * the fourth returns the elapsed virtual time for the current 192 // thread. 193 static bool supports_vtime(); 194 static bool enable_vtime(); 195 static bool vtime_enabled(); 196 static double elapsedVTime(); 197 198 // Return current local time in a string (YYYY-MM-DD HH:MM:SS). 199 // It is MT safe, but not async-safe, as reading time zone 200 // information may require a lock on some platforms. 201 static char* local_time_string(char *buf, size_t buflen); 202 static struct tm* localtime_pd (const time_t* clock, struct tm* res); 203 // Fill in buffer with current local time as an ISO-8601 string. 204 // E.g., YYYY-MM-DDThh:mm:ss.mmm+zzzz. 205 // Returns buffer, or NULL if it failed. 206 static char* iso8601_time(char* buffer, size_t buffer_length); 207 208 // Interface for detecting multiprocessor system 209 static inline bool is_MP() { 210 assert(_processor_count > 0, "invalid processor count"); 211 return _processor_count > 1 || AssumeMP; 212 } 213 static julong available_memory(); 214 static julong physical_memory(); 215 static bool has_allocatable_memory_limit(julong* limit); 216 static bool is_server_class_machine(); 217 218 // number of CPUs 219 static int processor_count() { 220 return _processor_count; 221 } 222 static void set_processor_count(int count) { _processor_count = count; } 223 224 // Returns the number of CPUs this process is currently allowed to run on. 225 // Note that on some OSes this can change dynamically. 226 static int active_processor_count(); 227 228 // Bind processes to processors. 229 // This is a two step procedure: 230 // first you generate a distribution of processes to processors, 231 // then you bind processes according to that distribution. 232 // Compute a distribution for number of processes to processors. 233 // Stores the processor id's into the distribution array argument. 234 // Returns true if it worked, false if it didn't. 235 static bool distribute_processes(uint length, uint* distribution); 236 // Binds the current process to a processor. 237 // Returns true if it worked, false if it didn't. 238 static bool bind_to_processor(uint processor_id); 239 240 // Give a name to the current thread. 241 static void set_native_thread_name(const char *name); 242 243 // Interface for stack banging (predetect possible stack overflow for 244 // exception processing) There are guard pages, and above that shadow 245 // pages for stack overflow checking. 246 static bool uses_stack_guard_pages(); 247 static bool allocate_stack_guard_pages(); 248 static void bang_stack_shadow_pages(); 249 static bool stack_shadow_pages_available(Thread *thread, methodHandle method); 250 251 // OS interface to Virtual Memory 252 253 // Return the default page size. 254 static int vm_page_size(); 255 256 // Return the page size to use for a region of memory. The min_pages argument 257 // is a hint intended to limit fragmentation; it says the returned page size 258 // should be <= region_max_size / min_pages. Because min_pages is a hint, 259 // this routine may return a size larger than region_max_size / min_pages. 260 // 261 // The current implementation ignores min_pages if a larger page size is an 262 // exact multiple of both region_min_size and region_max_size. This allows 263 // larger pages to be used when doing so would not cause fragmentation; in 264 // particular, a single page can be used when region_min_size == 265 // region_max_size == a supported page size. 266 static size_t page_size_for_region(size_t region_min_size, 267 size_t region_max_size, 268 uint min_pages); 269 // Return the largest page size that can be used 270 static size_t max_page_size() { 271 // The _page_sizes array is sorted in descending order. 272 return _page_sizes[0]; 273 } 274 275 // Methods for tracing page sizes returned by the above method; enabled by 276 // TracePageSizes. The region_{min,max}_size parameters should be the values 277 // passed to page_size_for_region() and page_size should be the result of that 278 // call. The (optional) base and size parameters should come from the 279 // ReservedSpace base() and size() methods. 280 static void trace_page_sizes(const char* str, const size_t* page_sizes, 281 int count) PRODUCT_RETURN; 282 static void trace_page_sizes(const char* str, const size_t region_min_size, 283 const size_t region_max_size, 284 const size_t page_size, 285 const char* base = NULL, 286 const size_t size = 0) PRODUCT_RETURN; 287 288 static int vm_allocation_granularity(); 289 static char* reserve_memory(size_t bytes, char* addr = 0, 290 size_t alignment_hint = 0); 291 static char* reserve_memory(size_t bytes, char* addr, 292 size_t alignment_hint, MEMFLAGS flags); 293 static char* reserve_memory_aligned(size_t size, size_t alignment); 294 static char* attempt_reserve_memory_at(size_t bytes, char* addr); 295 static void split_reserved_memory(char *base, size_t size, 296 size_t split, bool realloc); 297 static bool commit_memory(char* addr, size_t bytes, bool executable); 298 static bool commit_memory(char* addr, size_t size, size_t alignment_hint, 299 bool executable); 300 // Same as commit_memory() that either succeeds or calls 301 // vm_exit_out_of_memory() with the specified mesg. 302 static void commit_memory_or_exit(char* addr, size_t bytes, 303 bool executable, const char* mesg); 304 static void commit_memory_or_exit(char* addr, size_t size, 305 size_t alignment_hint, 306 bool executable, const char* mesg); 307 static bool uncommit_memory(char* addr, size_t bytes); 308 static bool release_memory(char* addr, size_t bytes); 309 310 enum ProtType { MEM_PROT_NONE, MEM_PROT_READ, MEM_PROT_RW, MEM_PROT_RWX }; 311 static bool protect_memory(char* addr, size_t bytes, ProtType prot, 312 bool is_committed = true); 313 314 static bool guard_memory(char* addr, size_t bytes); 315 static bool unguard_memory(char* addr, size_t bytes); 316 static bool create_stack_guard_pages(char* addr, size_t bytes); 317 static bool pd_create_stack_guard_pages(char* addr, size_t bytes); 318 static bool remove_stack_guard_pages(char* addr, size_t bytes); 319 320 static char* map_memory(int fd, const char* file_name, size_t file_offset, 321 char *addr, size_t bytes, bool read_only = false, 322 bool allow_exec = false); 323 static char* remap_memory(int fd, const char* file_name, size_t file_offset, 324 char *addr, size_t bytes, bool read_only, 325 bool allow_exec); 326 static bool unmap_memory(char *addr, size_t bytes); 327 static void free_memory(char *addr, size_t bytes, size_t alignment_hint); 328 static void realign_memory(char *addr, size_t bytes, size_t alignment_hint); 329 330 // NUMA-specific interface 331 static bool numa_has_static_binding(); 332 static bool numa_has_group_homing(); 333 static void numa_make_local(char *addr, size_t bytes, int lgrp_hint); 334 static void numa_make_global(char *addr, size_t bytes); 335 static size_t numa_get_groups_num(); 336 static size_t numa_get_leaf_groups(int *ids, size_t size); 337 static bool numa_topology_changed(); 338 static int numa_get_group_id(); 339 340 // Page manipulation 341 struct page_info { 342 size_t size; 343 int lgrp_id; 344 }; 345 static bool get_page_info(char *start, page_info* info); 346 static char* scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found); 347 348 static char* non_memory_address_word(); 349 // reserve, commit and pin the entire memory region 350 static char* reserve_memory_special(size_t size, size_t alignment, 351 char* addr, bool executable); 352 static bool release_memory_special(char* addr, size_t bytes); 353 static void large_page_init(); 354 static size_t large_page_size(); 355 static bool can_commit_large_page_memory(); 356 static bool can_execute_large_page_memory(); 357 358 // OS interface to polling page 359 static address get_polling_page() { return _polling_page; } 360 static void set_polling_page(address page) { _polling_page = page; } 361 static bool is_poll_address(address addr) { return addr >= _polling_page && addr < (_polling_page + os::vm_page_size()); } 362 static void make_polling_page_unreadable(); 363 static void make_polling_page_readable(); 364 365 // Routines used to serialize the thread state without using membars 366 static void serialize_thread_states(); 367 368 // Since we write to the serialize page from every thread, we 369 // want stores to be on unique cache lines whenever possible 370 // in order to minimize CPU cross talk. We pre-compute the 371 // amount to shift the thread* to make this offset unique to 372 // each thread. 373 static int get_serialize_page_shift_count() { 374 return SerializePageShiftCount; 375 } 376 377 static void set_serialize_page_mask(uintptr_t mask) { 378 _serialize_page_mask = mask; 379 } 380 381 static unsigned int get_serialize_page_mask() { 382 return _serialize_page_mask; 383 } 384 385 static void set_memory_serialize_page(address page); 386 387 static address get_memory_serialize_page() { 388 return (address)_mem_serialize_page; 389 } 390 391 static inline void write_memory_serialize_page(JavaThread *thread) { 392 uintptr_t page_offset = ((uintptr_t)thread >> 393 get_serialize_page_shift_count()) & 394 get_serialize_page_mask(); 395 *(volatile int32_t *)((uintptr_t)_mem_serialize_page+page_offset) = 1; 396 } 397 398 static bool is_memory_serialize_page(JavaThread *thread, address addr) { 399 if (UseMembar) return false; 400 // Previously this function calculated the exact address of this 401 // thread's serialize page, and checked if the faulting address 402 // was equal. However, some platforms mask off faulting addresses 403 // to the page size, so now we just check that the address is 404 // within the page. This makes the thread argument unnecessary, 405 // but we retain the NULL check to preserve existing behavior. 406 if (thread == NULL) return false; 407 address page = (address) _mem_serialize_page; 408 return addr >= page && addr < (page + os::vm_page_size()); 409 } 410 411 static void block_on_serialize_page_trap(); 412 413 // threads 414 415 enum ThreadType { 416 vm_thread, 417 cgc_thread, // Concurrent GC thread 418 pgc_thread, // Parallel GC thread 419 java_thread, 420 compiler_thread, 421 watcher_thread, 422 os_thread 423 }; 424 425 static bool create_thread(Thread* thread, 426 ThreadType thr_type, 427 size_t stack_size = 0); 428 static bool create_main_thread(JavaThread* thread); 429 static bool create_attached_thread(JavaThread* thread); 430 static void pd_start_thread(Thread* thread); 431 static void start_thread(Thread* thread); 432 433 static void initialize_thread(Thread* thr); 434 static void free_thread(OSThread* osthread); 435 436 // thread id on Linux/64bit is 64bit, on Windows and Solaris, it's 32bit 437 static intx current_thread_id(); 438 static int current_process_id(); 439 static int sleep(Thread* thread, jlong ms, bool interruptable); 440 // Short standalone OS sleep suitable for slow path spin loop. 441 // Ignores Thread.interrupt() (so keep it short). 442 // ms = 0, will sleep for the least amount of time allowed by the OS. 443 static void naked_short_sleep(jlong ms); 444 static void infinite_sleep(); // never returns, use with CAUTION 445 static void yield(); // Yields to all threads with same priority 446 enum YieldResult { 447 YIELD_SWITCHED = 1, // caller descheduled, other ready threads exist & ran 448 YIELD_NONEREADY = 0, // No other runnable/ready threads. 449 // platform-specific yield return immediately 450 YIELD_UNKNOWN = -1 // Unknown: platform doesn't support _SWITCHED or _NONEREADY 451 // YIELD_SWITCHED and YIELD_NONREADY imply the platform supports a "strong" 452 // yield that can be used in lieu of blocking. 453 } ; 454 static YieldResult NakedYield () ; 455 static void yield_all(); // Yields to all other threads including lower priority 456 // (for the default scheduling policy) 457 static OSReturn set_priority(Thread* thread, ThreadPriority priority); 458 static OSReturn get_priority(const Thread* const thread, ThreadPriority& priority); 459 460 static void interrupt(Thread* thread); 461 static bool is_interrupted(Thread* thread, bool clear_interrupted); 462 463 static int pd_self_suspend_thread(Thread* thread); 464 465 static ExtendedPC fetch_frame_from_context(void* ucVoid, intptr_t** sp, intptr_t** fp); 466 static frame fetch_frame_from_context(void* ucVoid); 467 468 static ExtendedPC get_thread_pc(Thread *thread); 469 static void breakpoint(); 470 471 static address current_stack_pointer(); 472 static address current_stack_base(); 473 static size_t current_stack_size(); 474 475 static void verify_stack_alignment() PRODUCT_RETURN; 476 477 static int message_box(const char* title, const char* message); 478 static char* do_you_want_to_debug(const char* message); 479 480 // run cmd in a separate process and return its exit code; or -1 on failures 481 static int fork_and_exec(char *cmd); 482 483 // Set file to send error reports. 484 static void set_error_file(const char *logfile); 485 486 // os::exit() is merged with vm_exit() 487 // static void exit(int num); 488 489 // Terminate the VM, but don't exit the process 490 static void shutdown(); 491 492 // Terminate with an error. Default is to generate a core file on platforms 493 // that support such things. This calls shutdown() and then aborts. 494 static void abort(bool dump_core = true); 495 496 // Die immediately, no exit hook, no abort hook, no cleanup. 497 static void die(); 498 499 // File i/o operations 500 static const int default_file_open_flags(); 501 static int open(const char *path, int oflag, int mode); 502 static FILE* open(int fd, const char* mode); 503 static int close(int fd); 504 static jlong lseek(int fd, jlong offset, int whence); 505 static char* native_path(char *path); 506 static int ftruncate(int fd, jlong length); 507 static int fsync(int fd); 508 static int available(int fd, jlong *bytes); 509 510 //File i/o operations 511 512 static size_t read(int fd, void *buf, unsigned int nBytes); 513 static size_t restartable_read(int fd, void *buf, unsigned int nBytes); 514 static size_t write(int fd, const void *buf, unsigned int nBytes); 515 516 // Reading directories. 517 static DIR* opendir(const char* dirname); 518 static int readdir_buf_size(const char *path); 519 static struct dirent* readdir(DIR* dirp, dirent* dbuf); 520 static int closedir(DIR* dirp); 521 522 // Dynamic library extension 523 static const char* dll_file_extension(); 524 525 static const char* get_temp_directory(); 526 static const char* get_current_directory(char *buf, size_t buflen); 527 528 // Builds a platform-specific full library path given a ld path and lib name 529 // Returns true if buffer contains full path to existing file, false otherwise 530 static bool dll_build_name(char* buffer, size_t size, 531 const char* pathname, const char* fname); 532 533 // Symbol lookup, find nearest function name; basically it implements 534 // dladdr() for all platforms. Name of the nearest function is copied 535 // to buf. Distance from its base address is optionally returned as offset. 536 // If function name is not found, buf[0] is set to '\0' and offset is 537 // set to -1 (if offset is non-NULL). 538 static bool dll_address_to_function_name(address addr, char* buf, 539 int buflen, int* offset); 540 541 // Locate DLL/DSO. On success, full path of the library is copied to 542 // buf, and offset is optionally set to be the distance between addr 543 // and the library's base address. On failure, buf[0] is set to '\0' 544 // and offset is set to -1 (if offset is non-NULL). 545 static bool dll_address_to_library_name(address addr, char* buf, 546 int buflen, int* offset); 547 548 // Find out whether the pc is in the static code for jvm.dll/libjvm.so. 549 static bool address_is_in_vm(address addr); 550 551 // Loads .dll/.so and 552 // in case of error it checks if .dll/.so was built for the 553 // same architecture as HotSpot is running on 554 static void* dll_load(const char *name, char *ebuf, int ebuflen); 555 556 // lookup symbol in a shared library 557 static void* dll_lookup(void* handle, const char* name); 558 559 // Unload library 560 static void dll_unload(void *lib); 561 562 // Return the handle of this process 563 static void* get_default_process_handle(); 564 565 // Check for static linked agent library 566 static bool find_builtin_agent(AgentLibrary *agent_lib, const char *syms[], 567 size_t syms_len); 568 569 // Find agent entry point 570 static void *find_agent_function(AgentLibrary *agent_lib, bool check_lib, 571 const char *syms[], size_t syms_len); 572 573 // Print out system information; they are called by fatal error handler. 574 // Output format may be different on different platforms. 575 static void print_os_info(outputStream* st); 576 static void print_os_info_brief(outputStream* st); 577 static void print_cpu_info(outputStream* st); 578 static void pd_print_cpu_info(outputStream* st); 579 static void print_memory_info(outputStream* st); 580 static void print_dll_info(outputStream* st); 581 static void print_environment_variables(outputStream* st, const char** env_list, char* buffer, int len); 582 static void print_context(outputStream* st, void* context); 583 static void print_register_info(outputStream* st, void* context); 584 static void print_siginfo(outputStream* st, void* siginfo); 585 static void print_signal_handlers(outputStream* st, char* buf, size_t buflen); 586 static void print_date_and_time(outputStream* st); 587 588 static void print_location(outputStream* st, intptr_t x, bool verbose = false); 589 static size_t lasterror(char *buf, size_t len); 590 static int get_last_error(); 591 592 // Determines whether the calling process is being debugged by a user-mode debugger. 593 static bool is_debugger_attached(); 594 595 // wait for a key press if PauseAtExit is set 596 static void wait_for_keypress_at_exit(void); 597 598 // The following two functions are used by fatal error handler to trace 599 // native (C) frames. They are not part of frame.hpp/frame.cpp because 600 // frame.hpp/cpp assume thread is JavaThread, and also because different 601 // OS/compiler may have different convention or provide different API to 602 // walk C frames. 603 // 604 // We don't attempt to become a debugger, so we only follow frames if that 605 // does not require a lookup in the unwind table, which is part of the binary 606 // file but may be unsafe to read after a fatal error. So on x86, we can 607 // only walk stack if %ebp is used as frame pointer; on ia64, it's not 608 // possible to walk C stack without having the unwind table. 609 static bool is_first_C_frame(frame *fr); 610 static frame get_sender_for_C_frame(frame *fr); 611 612 // return current frame. pc() and sp() are set to NULL on failure. 613 static frame current_frame(); 614 615 static void print_hex_dump(outputStream* st, address start, address end, int unitsize); 616 617 // returns a string to describe the exception/signal; 618 // returns NULL if exception_code is not an OS exception/signal. 619 static const char* exception_name(int exception_code, char* buf, size_t buflen); 620 621 // Returns native Java library, loads if necessary 622 static void* native_java_library(); 623 624 // Fills in path to jvm.dll/libjvm.so (used by the Disassembler) 625 static void jvm_path(char *buf, jint buflen); 626 627 // Returns true if we are running in a headless jre. 628 static bool is_headless_jre(); 629 630 // JNI names 631 static void print_jni_name_prefix_on(outputStream* st, int args_size); 632 static void print_jni_name_suffix_on(outputStream* st, int args_size); 633 634 // File conventions 635 static const char* file_separator(); 636 static const char* line_separator(); 637 static const char* path_separator(); 638 639 // Init os specific system properties values 640 static void init_system_properties_values(); 641 642 // IO operations, non-JVM_ version. 643 static int stat(const char* path, struct stat* sbuf); 644 static bool dir_is_empty(const char* path); 645 646 // IO operations on binary files 647 static int create_binary_file(const char* path, bool rewrite_existing); 648 static jlong current_file_offset(int fd); 649 static jlong seek_to_file_offset(int fd, jlong offset); 650 651 // Thread Local Storage 652 static int allocate_thread_local_storage(); 653 static void thread_local_storage_at_put(int index, void* value); 654 static void* thread_local_storage_at(int index); 655 static void free_thread_local_storage(int index); 656 657 // Stack walk 658 static address get_caller_pc(int n = 0); 659 660 // General allocation (must be MT-safe) 661 static void* malloc (size_t size, MEMFLAGS flags, address caller_pc = 0); 662 static void* realloc (void *memblock, size_t size, MEMFLAGS flags, address caller_pc = 0); 663 static void free (void *memblock, MEMFLAGS flags = mtNone); 664 static bool check_heap(bool force = false); // verify C heap integrity 665 static char* strdup(const char *, MEMFLAGS flags = mtInternal); // Like strdup 666 667#ifndef PRODUCT 668 static julong num_mallocs; // # of calls to malloc/realloc 669 static julong alloc_bytes; // # of bytes allocated 670 static julong num_frees; // # of calls to free 671 static julong free_bytes; // # of bytes freed 672#endif 673 674 // SocketInterface (ex HPI SocketInterface ) 675 static int socket(int domain, int type, int protocol); 676 static int socket_close(int fd); 677 static int socket_shutdown(int fd, int howto); 678 static int recv(int fd, char* buf, size_t nBytes, uint flags); 679 static int send(int fd, char* buf, size_t nBytes, uint flags); 680 static int raw_send(int fd, char* buf, size_t nBytes, uint flags); 681 static int timeout(int fd, long timeout); 682 static int listen(int fd, int count); 683 static int connect(int fd, struct sockaddr* him, socklen_t len); 684 static int bind(int fd, struct sockaddr* him, socklen_t len); 685 static int accept(int fd, struct sockaddr* him, socklen_t* len); 686 static int recvfrom(int fd, char* buf, size_t nbytes, uint flags, 687 struct sockaddr* from, socklen_t* fromlen); 688 static int get_sock_name(int fd, struct sockaddr* him, socklen_t* len); 689 static int sendto(int fd, char* buf, size_t len, uint flags, 690 struct sockaddr* to, socklen_t tolen); 691 static int socket_available(int fd, jint* pbytes); 692 693 static int get_sock_opt(int fd, int level, int optname, 694 char* optval, socklen_t* optlen); 695 static int set_sock_opt(int fd, int level, int optname, 696 const char* optval, socklen_t optlen); 697 static int get_host_name(char* name, int namelen); 698 699 static struct hostent* get_host_by_name(char* name); 700 701 // Support for signals (see JVM_RaiseSignal, JVM_RegisterSignal) 702 static void signal_init(); 703 static void signal_init_pd(); 704 static void signal_notify(int signal_number); 705 static void* signal(int signal_number, void* handler); 706 static void signal_raise(int signal_number); 707 static int signal_wait(); 708 static int signal_lookup(); 709 static void* user_handler(); 710 static void terminate_signal_thread(); 711 static int sigexitnum_pd(); 712 713 // random number generation 714 static long random(); // return 32bit pseudorandom number 715 static void init_random(long initval); // initialize random sequence 716 717 // Structured OS Exception support 718 static void os_exception_wrapper(java_call_t f, JavaValue* value, methodHandle* method, JavaCallArguments* args, Thread* thread); 719 720 // On Windows this will create an actual minidump, on Linux/Solaris it will simply check core dump limits 721 static void check_or_create_dump(void* exceptionRecord, void* contextRecord, char* buffer, size_t bufferSize); 722 723 // Get the default path to the core file 724 // Returns the length of the string 725 static int get_core_path(char* buffer, size_t bufferSize); 726 727 // JVMTI & JVM monitoring and management support 728 // The thread_cpu_time() and current_thread_cpu_time() are only 729 // supported if is_thread_cpu_time_supported() returns true. 730 // They are not supported on Solaris T1. 731 732 // Thread CPU Time - return the fast estimate on a platform 733 // On Solaris - call gethrvtime (fast) - user time only 734 // On Linux - fast clock_gettime where available - user+sys 735 // - otherwise: very slow /proc fs - user+sys 736 // On Windows - GetThreadTimes - user+sys 737 static jlong current_thread_cpu_time(); 738 static jlong thread_cpu_time(Thread* t); 739 740 // Thread CPU Time with user_sys_cpu_time parameter. 741 // 742 // If user_sys_cpu_time is true, user+sys time is returned. 743 // Otherwise, only user time is returned 744 static jlong current_thread_cpu_time(bool user_sys_cpu_time); 745 static jlong thread_cpu_time(Thread* t, bool user_sys_cpu_time); 746 747 // Return a bunch of info about the timers. 748 // Note that the returned info for these two functions may be different 749 // on some platforms 750 static void current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr); 751 static void thread_cpu_time_info(jvmtiTimerInfo *info_ptr); 752 753 static bool is_thread_cpu_time_supported(); 754 755 // System loadavg support. Returns -1 if load average cannot be obtained. 756 static int loadavg(double loadavg[], int nelem); 757 758 // Hook for os specific jvm options that we don't want to abort on seeing 759 static bool obsolete_option(const JavaVMOption *option); 760 761 // Extensions 762#include "runtime/os_ext.hpp" 763 764 public: 765 class CrashProtectionCallback : public StackObj { 766 public: 767 virtual void call() = 0; 768 }; 769 770 // Platform dependent stuff 771#ifdef TARGET_OS_FAMILY_linux 772# include "os_linux.hpp" 773# include "os_posix.hpp" 774#endif 775#ifdef TARGET_OS_FAMILY_solaris 776# include "os_solaris.hpp" 777# include "os_posix.hpp" 778#endif 779#ifdef TARGET_OS_FAMILY_windows 780# include "os_windows.hpp" 781#endif 782#ifdef TARGET_OS_FAMILY_aix 783# include "os_aix.hpp" 784# include "os_posix.hpp" 785#endif 786#ifdef TARGET_OS_FAMILY_bsd 787# include "os_posix.hpp" 788# include "os_bsd.hpp" 789#endif 790#ifdef TARGET_OS_ARCH_linux_x86 791# include "os_linux_x86.hpp" 792#endif 793#ifdef TARGET_OS_ARCH_linux_sparc 794# include "os_linux_sparc.hpp" 795#endif 796#ifdef TARGET_OS_ARCH_linux_zero 797# include "os_linux_zero.hpp" 798#endif 799#ifdef TARGET_OS_ARCH_solaris_x86 800# include "os_solaris_x86.hpp" 801#endif 802#ifdef TARGET_OS_ARCH_solaris_sparc 803# include "os_solaris_sparc.hpp" 804#endif 805#ifdef TARGET_OS_ARCH_windows_x86 806# include "os_windows_x86.hpp" 807#endif 808#ifdef TARGET_OS_ARCH_linux_arm 809# include "os_linux_arm.hpp" 810#endif 811#ifdef TARGET_OS_ARCH_linux_ppc 812# include "os_linux_ppc.hpp" 813#endif 814#ifdef TARGET_OS_ARCH_aix_ppc 815# include "os_aix_ppc.hpp" 816#endif 817#ifdef TARGET_OS_ARCH_bsd_x86 818# include "os_bsd_x86.hpp" 819#endif 820#ifdef TARGET_OS_ARCH_bsd_zero 821# include "os_bsd_zero.hpp" 822#endif 823 824#ifndef OS_NATIVE_THREAD_CREATION_FAILED_MSG 825#define OS_NATIVE_THREAD_CREATION_FAILED_MSG "unable to create native thread: possibly out of memory or process/resource limits reached" 826#endif 827 828 public: 829#ifndef PLATFORM_PRINT_NATIVE_STACK 830 // No platform-specific code for printing the native stack. 831 static bool platform_print_native_stack(outputStream* st, void* context, 832 char *buf, int buf_size) { 833 return false; 834 } 835#endif 836 837 // debugging support (mostly used by debug.cpp but also fatal error handler) 838 static bool find(address pc, outputStream* st = tty); // OS specific function to make sense out of an address 839 840 static bool dont_yield(); // when true, JVM_Yield() is nop 841 static void print_statistics(); 842 843 // Thread priority helpers (implemented in OS-specific part) 844 static OSReturn set_native_priority(Thread* thread, int native_prio); 845 static OSReturn get_native_priority(const Thread* const thread, int* priority_ptr); 846 static int java_to_os_priority[CriticalPriority + 1]; 847 // Hint to the underlying OS that a task switch would not be good. 848 // Void return because it's a hint and can fail. 849 static void hint_no_preempt(); 850 static const char* native_thread_creation_failed_msg() { 851 return OS_NATIVE_THREAD_CREATION_FAILED_MSG; 852 } 853 854 // Used at creation if requested by the diagnostic flag PauseAtStartup. 855 // Causes the VM to wait until an external stimulus has been applied 856 // (for Unix, that stimulus is a signal, for Windows, an external 857 // ResumeThread call) 858 static void pause(); 859 860 // Builds a platform dependent Agent_OnLoad_<libname> function name 861 // which is used to find statically linked in agents. 862 static char* build_agent_function_name(const char *sym, const char *cname, 863 bool is_absolute_path); 864 865 class SuspendedThreadTaskContext { 866 public: 867 SuspendedThreadTaskContext(Thread* thread, void *ucontext) : _thread(thread), _ucontext(ucontext) {} 868 Thread* thread() const { return _thread; } 869 void* ucontext() const { return _ucontext; } 870 private: 871 Thread* _thread; 872 void* _ucontext; 873 }; 874 875 class SuspendedThreadTask { 876 public: 877 SuspendedThreadTask(Thread* thread) : _thread(thread), _done(false) {} 878 virtual ~SuspendedThreadTask() {} 879 void run(); 880 bool is_done() { return _done; } 881 virtual void do_task(const SuspendedThreadTaskContext& context) = 0; 882 protected: 883 private: 884 void internal_do_task(); 885 Thread* _thread; 886 bool _done; 887 }; 888 889#ifndef TARGET_OS_FAMILY_windows 890 // Suspend/resume support 891 // Protocol: 892 // 893 // a thread starts in SR_RUNNING 894 // 895 // SR_RUNNING can go to 896 // * SR_SUSPEND_REQUEST when the WatcherThread wants to suspend it 897 // SR_SUSPEND_REQUEST can go to 898 // * SR_RUNNING if WatcherThread decides it waited for SR_SUSPENDED too long (timeout) 899 // * SR_SUSPENDED if the stopped thread receives the signal and switches state 900 // SR_SUSPENDED can go to 901 // * SR_WAKEUP_REQUEST when the WatcherThread has done the work and wants to resume 902 // SR_WAKEUP_REQUEST can go to 903 // * SR_RUNNING when the stopped thread receives the signal 904 // * SR_WAKEUP_REQUEST on timeout (resend the signal and try again) 905 class SuspendResume { 906 public: 907 enum State { 908 SR_RUNNING, 909 SR_SUSPEND_REQUEST, 910 SR_SUSPENDED, 911 SR_WAKEUP_REQUEST 912 }; 913 914 private: 915 volatile State _state; 916 917 private: 918 /* try to switch state from state "from" to state "to" 919 * returns the state set after the method is complete 920 */ 921 State switch_state(State from, State to); 922 923 public: 924 SuspendResume() : _state(SR_RUNNING) { } 925 926 State state() const { return _state; } 927 928 State request_suspend() { 929 return switch_state(SR_RUNNING, SR_SUSPEND_REQUEST); 930 } 931 932 State cancel_suspend() { 933 return switch_state(SR_SUSPEND_REQUEST, SR_RUNNING); 934 } 935 936 State suspended() { 937 return switch_state(SR_SUSPEND_REQUEST, SR_SUSPENDED); 938 } 939 940 State request_wakeup() { 941 return switch_state(SR_SUSPENDED, SR_WAKEUP_REQUEST); 942 } 943 944 State running() { 945 return switch_state(SR_WAKEUP_REQUEST, SR_RUNNING); 946 } 947 948 bool is_running() const { 949 return _state == SR_RUNNING; 950 } 951 952 bool is_suspend_request() const { 953 return _state == SR_SUSPEND_REQUEST; 954 } 955 956 bool is_suspended() const { 957 return _state == SR_SUSPENDED; 958 } 959 }; 960#endif 961 962 963 protected: 964 static long _rand_seed; // seed for random number generator 965 static int _processor_count; // number of processors 966 967 static char* format_boot_path(const char* format_string, 968 const char* home, 969 int home_len, 970 char fileSep, 971 char pathSep); 972 static bool set_boot_path(char fileSep, char pathSep); 973 static char** split_path(const char* path, int* n); 974 975}; 976 977// Note that "PAUSE" is almost always used with synchronization 978// so arguably we should provide Atomic::SpinPause() instead 979// of the global SpinPause() with C linkage. 980// It'd also be eligible for inlining on many platforms. 981 982extern "C" int SpinPause(); 983 984#endif // SHARE_VM_RUNTIME_OS_HPP 985