1 /* 2 * Copyright (c) 1997, 2013, 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_bsd 45 # include "jvm_bsd.h" 46 # include <setjmp.h> 47 #endif 48 49 class AgentLibrary; 50 51 // os defines the interface to operating system; this includes traditional 52 // OS services (time, I/O) as well as other functionality with system- 53 // dependent code. 54 55 typedef void (*dll_func)(...); 56 57 class Thread; 58 class JavaThread; 59 class Event; 60 class DLL; 61 class FileHandle; 62 template<class E> class GrowableArray; 63 64 // %%%%% Moved ThreadState, START_FN, OSThread to new osThread.hpp. -- Rose 65 66 // Platform-independent error return values from OS functions 67 enum OSReturn { 68 OS_OK = 0, // Operation was successful 69 OS_ERR = -1, // Operation failed 70 OS_INTRPT = -2, // Operation was interrupted 71 OS_TIMEOUT = -3, // Operation timed out 72 OS_NOMEM = -5, // Operation failed for lack of memory 73 OS_NORESOURCE = -6 // Operation failed for lack of nonmemory resource 74 }; 75 76 enum ThreadPriority { // JLS 20.20.1-3 77 NoPriority = -1, // Initial non-priority value 78 MinPriority = 1, // Minimum priority 79 NormPriority = 5, // Normal (non-daemon) priority 80 NearMaxPriority = 9, // High priority, used for VMThread 81 MaxPriority = 10, // Highest priority, used for WatcherThread 82 // ensures that VMThread doesn't starve profiler 83 CriticalPriority = 11 // Critical thread priority 84 }; 85 86 // Executable parameter flag for os::commit_memory() and 87 // os::commit_memory_or_exit(). 88 const bool ExecMem = true; 89 90 // Typedef for structured exception handling support 91 typedef void (*java_call_t)(JavaValue* value, methodHandle* method, JavaCallArguments* args, Thread* thread); 92 93 class os: AllStatic { 94 friend class VMStructs; 95 96 public: 97 enum { page_sizes_max = 9 }; // Size of _page_sizes array (8 plus a sentinel) 98 99 private: 100 static OSThread* _starting_thread; 101 static address _polling_page; 102 static volatile int32_t * _mem_serialize_page; 103 static uintptr_t _serialize_page_mask; 104 public: 105 static size_t _page_sizes[page_sizes_max]; 106 107 private: 108 static void init_page_sizes(size_t default_page_size) { 109 _page_sizes[0] = default_page_size; 110 _page_sizes[1] = 0; // sentinel 111 } 112 113 static char* pd_reserve_memory(size_t bytes, char* addr = 0, 114 size_t alignment_hint = 0); 115 static char* pd_attempt_reserve_memory_at(size_t bytes, char* addr); 116 static void pd_split_reserved_memory(char *base, size_t size, 117 size_t split, bool realloc); 118 static bool pd_commit_memory(char* addr, size_t bytes, bool executable); 119 static bool pd_commit_memory(char* addr, size_t size, size_t alignment_hint, 120 bool executable); 121 // Same as pd_commit_memory() that either succeeds or calls 122 // vm_exit_out_of_memory() with the specified mesg. 123 static void pd_commit_memory_or_exit(char* addr, size_t bytes, 124 bool executable, const char* mesg); 125 static void pd_commit_memory_or_exit(char* addr, size_t size, 126 size_t alignment_hint, 127 bool executable, const char* mesg); 128 static bool pd_uncommit_memory(char* addr, size_t bytes); 129 static bool pd_release_memory(char* addr, size_t bytes); 130 131 static char* pd_map_memory(int fd, const char* file_name, size_t file_offset, 132 char *addr, size_t bytes, bool read_only = false, 133 bool allow_exec = false); 134 static char* pd_remap_memory(int fd, const char* file_name, size_t file_offset, 135 char *addr, size_t bytes, bool read_only, 136 bool allow_exec); 137 static bool pd_unmap_memory(char *addr, size_t bytes); 138 static void pd_free_memory(char *addr, size_t bytes, size_t alignment_hint); 139 static void pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint); 140 141 142 public: 143 static void init(void); // Called before command line parsing 144 static jint init_2(void); // Called after command line parsing 145 static void init_globals(void) { // Called from init_globals() in init.cpp 146 init_globals_ext(); 147 } 148 static void init_3(void); // Called at the end of vm init 149 150 // File names are case-insensitive on windows only 151 // Override me as needed 152 static int file_name_strcmp(const char* s1, const char* s2); 153 154 static bool getenv(const char* name, char* buffer, int len); 155 static bool have_special_privileges(); 156 157 static jlong javaTimeMillis(); 158 static jlong javaTimeNanos(); 159 static void javaTimeNanos_info(jvmtiTimerInfo *info_ptr); 160 static void run_periodic_checks(); 161 162 163 // Returns the elapsed time in seconds since the vm started. 164 static double elapsedTime(); 165 166 // Returns real time in seconds since an arbitrary point 167 // in the past. 168 static bool getTimesSecs(double* process_real_time, 169 double* process_user_time, 170 double* process_system_time); 171 172 // Interface to the performance counter 173 static jlong elapsed_counter(); 174 static jlong elapsed_frequency(); 175 176 // The "virtual time" of a thread is the amount of time a thread has 177 // actually run. The first function indicates whether the OS supports 178 // this functionality for the current thread, and if so: 179 // * the second enables vtime tracking (if that is required). 180 // * the third tells whether vtime is enabled. 181 // * the fourth returns the elapsed virtual time for the current 182 // thread. 183 static bool supports_vtime(); 184 static bool enable_vtime(); 185 static bool vtime_enabled(); 186 static double elapsedVTime(); 187 188 // Return current local time in a string (YYYY-MM-DD HH:MM:SS). 189 // It is MT safe, but not async-safe, as reading time zone 190 // information may require a lock on some platforms. 191 static char* local_time_string(char *buf, size_t buflen); 192 static struct tm* localtime_pd (const time_t* clock, struct tm* res); 193 // Fill in buffer with current local time as an ISO-8601 string. 194 // E.g., YYYY-MM-DDThh:mm:ss.mmm+zzzz. 195 // Returns buffer, or NULL if it failed. 196 static char* iso8601_time(char* buffer, size_t buffer_length); 197 198 // Interface for detecting multiprocessor system 199 static inline bool is_MP() { 200 assert(_processor_count > 0, "invalid processor count"); 201 return _processor_count > 1 || AssumeMP; 202 } 203 static julong available_memory(); 204 static julong physical_memory(); 205 static bool has_allocatable_memory_limit(julong* limit); 206 static bool is_server_class_machine(); 207 208 // number of CPUs 209 static int processor_count() { 210 return _processor_count; 211 } 212 static void set_processor_count(int count) { _processor_count = count; } 213 214 // Returns the number of CPUs this process is currently allowed to run on. 215 // Note that on some OSes this can change dynamically. 216 static int active_processor_count(); 217 218 // Bind processes to processors. 219 // This is a two step procedure: 220 // first you generate a distribution of processes to processors, 221 // then you bind processes according to that distribution. 222 // Compute a distribution for number of processes to processors. 223 // Stores the processor id's into the distribution array argument. 224 // Returns true if it worked, false if it didn't. 225 static bool distribute_processes(uint length, uint* distribution); 226 // Binds the current process to a processor. 227 // Returns true if it worked, false if it didn't. 228 static bool bind_to_processor(uint processor_id); 229 230 // Give a name to the current thread. 231 static void set_native_thread_name(const char *name); 232 233 // Interface for stack banging (predetect possible stack overflow for 234 // exception processing) There are guard pages, and above that shadow 235 // pages for stack overflow checking. 236 static bool uses_stack_guard_pages(); 237 static bool allocate_stack_guard_pages(); 238 static void bang_stack_shadow_pages(); 239 static bool stack_shadow_pages_available(Thread *thread, methodHandle method); 240 241 // OS interface to Virtual Memory 242 243 // Return the default page size. 244 static int vm_page_size(); 245 246 // Return the page size to use for a region of memory. The min_pages argument 247 // is a hint intended to limit fragmentation; it says the returned page size 248 // should be <= region_max_size / min_pages. Because min_pages is a hint, 249 // this routine may return a size larger than region_max_size / min_pages. 250 // 251 // The current implementation ignores min_pages if a larger page size is an 252 // exact multiple of both region_min_size and region_max_size. This allows 253 // larger pages to be used when doing so would not cause fragmentation; in 254 // particular, a single page can be used when region_min_size == 255 // region_max_size == a supported page size. 256 static size_t page_size_for_region(size_t region_min_size, 257 size_t region_max_size, 258 uint min_pages); 259 260 // Methods for tracing page sizes returned by the above method; enabled by 261 // TracePageSizes. The region_{min,max}_size parameters should be the values 262 // passed to page_size_for_region() and page_size should be the result of that 263 // call. The (optional) base and size parameters should come from the 264 // ReservedSpace base() and size() methods. 265 static void trace_page_sizes(const char* str, const size_t* page_sizes, 266 int count) PRODUCT_RETURN; 267 static void trace_page_sizes(const char* str, const size_t region_min_size, 268 const size_t region_max_size, 269 const size_t page_size, 270 const char* base = NULL, 271 const size_t size = 0) PRODUCT_RETURN; 272 273 static int vm_allocation_granularity(); 274 static char* reserve_memory(size_t bytes, char* addr = 0, 275 size_t alignment_hint = 0); 276 static char* reserve_memory(size_t bytes, char* addr, 277 size_t alignment_hint, MEMFLAGS flags); 278 static char* reserve_memory_aligned(size_t size, size_t alignment); 279 static char* attempt_reserve_memory_at(size_t bytes, char* addr); 280 static void split_reserved_memory(char *base, size_t size, 281 size_t split, bool realloc); 282 static bool commit_memory(char* addr, size_t bytes, bool executable); 283 static bool commit_memory(char* addr, size_t size, size_t alignment_hint, 284 bool executable); 285 // Same as commit_memory() that either succeeds or calls 286 // vm_exit_out_of_memory() with the specified mesg. 287 static void commit_memory_or_exit(char* addr, size_t bytes, 288 bool executable, const char* mesg); 289 static void commit_memory_or_exit(char* addr, size_t size, 290 size_t alignment_hint, 291 bool executable, const char* mesg); 292 static bool uncommit_memory(char* addr, size_t bytes); 293 static bool release_memory(char* addr, size_t bytes); 294 295 enum ProtType { MEM_PROT_NONE, MEM_PROT_READ, MEM_PROT_RW, MEM_PROT_RWX }; 296 static bool protect_memory(char* addr, size_t bytes, ProtType prot, 297 bool is_committed = true); 298 299 static bool guard_memory(char* addr, size_t bytes); 300 static bool unguard_memory(char* addr, size_t bytes); 301 static bool create_stack_guard_pages(char* addr, size_t bytes); 302 static bool pd_create_stack_guard_pages(char* addr, size_t bytes); 303 static bool remove_stack_guard_pages(char* addr, size_t bytes); 304 305 static char* map_memory(int fd, const char* file_name, size_t file_offset, 306 char *addr, size_t bytes, bool read_only = false, 307 bool allow_exec = false); 308 static char* remap_memory(int fd, const char* file_name, size_t file_offset, 309 char *addr, size_t bytes, bool read_only, 310 bool allow_exec); 311 static bool unmap_memory(char *addr, size_t bytes); 312 static void free_memory(char *addr, size_t bytes, size_t alignment_hint); 313 static void realign_memory(char *addr, size_t bytes, size_t alignment_hint); 314 315 // NUMA-specific interface 316 static bool numa_has_static_binding(); 317 static bool numa_has_group_homing(); 318 static void numa_make_local(char *addr, size_t bytes, int lgrp_hint); 319 static void numa_make_global(char *addr, size_t bytes); 320 static size_t numa_get_groups_num(); 321 static size_t numa_get_leaf_groups(int *ids, size_t size); 322 static bool numa_topology_changed(); 323 static int numa_get_group_id(); 324 325 // Page manipulation 326 struct page_info { 327 size_t size; 328 int lgrp_id; 329 }; 330 static bool get_page_info(char *start, page_info* info); 331 static char* scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found); 332 333 static char* non_memory_address_word(); 334 // reserve, commit and pin the entire memory region 335 static char* reserve_memory_special(size_t size, size_t alignment, 336 char* addr, bool executable); 337 static bool release_memory_special(char* addr, size_t bytes); 338 static void large_page_init(); 339 static size_t large_page_size(); 340 static bool can_commit_large_page_memory(); 341 static bool can_execute_large_page_memory(); 342 343 // OS interface to polling page 344 static address get_polling_page() { return _polling_page; } 345 static void set_polling_page(address page) { _polling_page = page; } 346 static bool is_poll_address(address addr) { return addr >= _polling_page && addr < (_polling_page + os::vm_page_size()); } 347 static void make_polling_page_unreadable(); 348 static void make_polling_page_readable(); 349 350 // Routines used to serialize the thread state without using membars 351 static void serialize_thread_states(); 352 353 // Since we write to the serialize page from every thread, we 354 // want stores to be on unique cache lines whenever possible 355 // in order to minimize CPU cross talk. We pre-compute the 356 // amount to shift the thread* to make this offset unique to 357 // each thread. 358 static int get_serialize_page_shift_count() { 359 return SerializePageShiftCount; 360 } 361 362 static void set_serialize_page_mask(uintptr_t mask) { 363 _serialize_page_mask = mask; 364 } 365 366 static unsigned int get_serialize_page_mask() { 367 return _serialize_page_mask; 368 } 369 370 static void set_memory_serialize_page(address page); 371 372 static address get_memory_serialize_page() { 373 return (address)_mem_serialize_page; 374 } 375 376 static inline void write_memory_serialize_page(JavaThread *thread) { 377 uintptr_t page_offset = ((uintptr_t)thread >> 378 get_serialize_page_shift_count()) & 379 get_serialize_page_mask(); 380 *(volatile int32_t *)((uintptr_t)_mem_serialize_page+page_offset) = 1; 381 } 382 383 static bool is_memory_serialize_page(JavaThread *thread, address addr) { 384 if (UseMembar) return false; 385 // Previously this function calculated the exact address of this 386 // thread's serialize page, and checked if the faulting address 387 // was equal. However, some platforms mask off faulting addresses 388 // to the page size, so now we just check that the address is 389 // within the page. This makes the thread argument unnecessary, 390 // but we retain the NULL check to preserve existing behaviour. 391 if (thread == NULL) return false; 392 address page = (address) _mem_serialize_page; 393 return addr >= page && addr < (page + os::vm_page_size()); 394 } 395 396 static void block_on_serialize_page_trap(); 397 398 // threads 399 400 enum ThreadType { 401 vm_thread, 402 cgc_thread, // Concurrent GC thread 403 pgc_thread, // Parallel GC thread 404 java_thread, 405 compiler_thread, 406 watcher_thread, 407 os_thread 408 }; 409 410 static bool create_thread(Thread* thread, 411 ThreadType thr_type, 412 size_t stack_size = 0); 413 static bool create_main_thread(JavaThread* thread); 414 static bool create_attached_thread(JavaThread* thread); 415 static void pd_start_thread(Thread* thread); 416 static void start_thread(Thread* thread); 417 418 static void initialize_thread(Thread* thr); 419 static void free_thread(OSThread* osthread); 420 421 // thread id on Linux/64bit is 64bit, on Windows and Solaris, it's 32bit 422 static intx current_thread_id(); 423 static int current_process_id(); 424 static int sleep(Thread* thread, jlong ms, bool interruptable); 425 static int naked_sleep(); 426 static void infinite_sleep(); // never returns, use with CAUTION 427 static void yield(); // Yields to all threads with same priority 428 enum YieldResult { 429 YIELD_SWITCHED = 1, // caller descheduled, other ready threads exist & ran 430 YIELD_NONEREADY = 0, // No other runnable/ready threads. 431 // platform-specific yield return immediately 432 YIELD_UNKNOWN = -1 // Unknown: platform doesn't support _SWITCHED or _NONEREADY 433 // YIELD_SWITCHED and YIELD_NONREADY imply the platform supports a "strong" 434 // yield that can be used in lieu of blocking. 435 } ; 436 static YieldResult NakedYield () ; 437 static void yield_all(int attempts = 0); // Yields to all other threads including lower priority 438 static void loop_breaker(int attempts); // called from within tight loops to possibly influence time-sharing 439 static OSReturn set_priority(Thread* thread, ThreadPriority priority); 440 static OSReturn get_priority(const Thread* const thread, ThreadPriority& priority); 441 442 static void interrupt(Thread* thread); 443 static bool is_interrupted(Thread* thread, bool clear_interrupted); 444 445 static int pd_self_suspend_thread(Thread* thread); 446 447 static ExtendedPC fetch_frame_from_context(void* ucVoid, intptr_t** sp, intptr_t** fp); 448 static frame fetch_frame_from_context(void* ucVoid); 449 450 static ExtendedPC get_thread_pc(Thread *thread); 451 static void breakpoint(); 452 453 static address current_stack_pointer(); 454 static address current_stack_base(); 455 static size_t current_stack_size(); 456 457 static void verify_stack_alignment() PRODUCT_RETURN; 458 459 static int message_box(const char* title, const char* message); 460 static char* do_you_want_to_debug(const char* message); 461 462 // run cmd in a separate process and return its exit code; or -1 on failures 463 static int fork_and_exec(char *cmd); 464 465 // Set file to send error reports. 466 static void set_error_file(const char *logfile); 467 468 // os::exit() is merged with vm_exit() 469 // static void exit(int num); 470 471 // Terminate the VM, but don't exit the process 472 static void shutdown(); 473 474 // Terminate with an error. Default is to generate a core file on platforms 475 // that support such things. This calls shutdown() and then aborts. 476 static void abort(bool dump_core = true); 477 478 // Die immediately, no exit hook, no abort hook, no cleanup. 479 static void die(); 480 481 // File i/o operations 482 static const int default_file_open_flags(); 483 static int open(const char *path, int oflag, int mode); 484 static FILE* open(int fd, const char* mode); 485 static int close(int fd); 486 static jlong lseek(int fd, jlong offset, int whence); 487 static char* native_path(char *path); 488 static int ftruncate(int fd, jlong length); 489 static int fsync(int fd); 490 static int available(int fd, jlong *bytes); 491 492 //File i/o operations 493 494 static size_t read(int fd, void *buf, unsigned int nBytes); 495 static size_t restartable_read(int fd, void *buf, unsigned int nBytes); 496 static size_t write(int fd, const void *buf, unsigned int nBytes); 497 498 // Reading directories. 499 static DIR* opendir(const char* dirname); 500 static int readdir_buf_size(const char *path); 501 static struct dirent* readdir(DIR* dirp, dirent* dbuf); 502 static int closedir(DIR* dirp); 503 504 // Dynamic library extension 505 static const char* dll_file_extension(); 506 507 static const char* get_temp_directory(); 508 static const char* get_current_directory(char *buf, size_t buflen); 509 510 // Builds a platform-specific full library path given a ld path and lib name 511 // Returns true if buffer contains full path to existing file, false otherwise 512 static bool dll_build_name(char* buffer, size_t size, 513 const char* pathname, const char* fname); 514 515 // Symbol lookup, find nearest function name; basically it implements 516 // dladdr() for all platforms. Name of the nearest function is copied 517 // to buf. Distance from its base address is optionally returned as offset. 518 // If function name is not found, buf[0] is set to '\0' and offset is 519 // set to -1 (if offset is non-NULL). 520 static bool dll_address_to_function_name(address addr, char* buf, 521 int buflen, int* offset); 522 523 // Locate DLL/DSO. On success, full path of the library is copied to 524 // buf, and offset is optionally set to be the distance between addr 525 // and the library's base address. On failure, buf[0] is set to '\0' 526 // and offset is set to -1 (if offset is non-NULL). 527 static bool dll_address_to_library_name(address addr, char* buf, 528 int buflen, int* offset); 529 530 // Find out whether the pc is in the static code for jvm.dll/libjvm.so. 531 static bool address_is_in_vm(address addr); 532 533 // Loads .dll/.so and 534 // in case of error it checks if .dll/.so was built for the 535 // same architecture as Hotspot is running on 536 static void* dll_load(const char *name, char *ebuf, int ebuflen); 537 538 // lookup symbol in a shared library 539 static void* dll_lookup(void* handle, const char* name); 540 541 // Unload library 542 static void dll_unload(void *lib); 543 544 // Return the handle of this process 545 static void* get_default_process_handle(); 546 547 // Check for static linked agent library 548 static bool find_builtin_agent(AgentLibrary *agent_lib, const char *syms[], 549 size_t syms_len); 550 551 // Find agent entry point 552 static void *find_agent_function(AgentLibrary *agent_lib, bool check_lib, 553 const char *syms[], size_t syms_len); 554 555 // Print out system information; they are called by fatal error handler. 556 // Output format may be different on different platforms. 557 static void print_os_info(outputStream* st); 558 static void print_os_info_brief(outputStream* st); 559 static void print_cpu_info(outputStream* st); 560 static void pd_print_cpu_info(outputStream* st); 561 static void print_memory_info(outputStream* st); 562 static void print_dll_info(outputStream* st); 563 static void print_environment_variables(outputStream* st, const char** env_list, char* buffer, int len); 564 static void print_context(outputStream* st, void* context); 565 static void print_register_info(outputStream* st, void* context); 566 static void print_siginfo(outputStream* st, void* siginfo); 567 static void print_signal_handlers(outputStream* st, char* buf, size_t buflen); 568 static void print_date_and_time(outputStream* st); 569 570 static void print_location(outputStream* st, intptr_t x, bool verbose = false); 571 static size_t lasterror(char *buf, size_t len); 572 static int get_last_error(); 573 574 // Determines whether the calling process is being debugged by a user-mode debugger. 575 static bool is_debugger_attached(); 576 577 // wait for a key press if PauseAtExit is set 578 static void wait_for_keypress_at_exit(void); 579 580 // The following two functions are used by fatal error handler to trace 581 // native (C) frames. They are not part of frame.hpp/frame.cpp because 582 // frame.hpp/cpp assume thread is JavaThread, and also because different 583 // OS/compiler may have different convention or provide different API to 584 // walk C frames. 585 // 586 // We don't attempt to become a debugger, so we only follow frames if that 587 // does not require a lookup in the unwind table, which is part of the binary 588 // file but may be unsafe to read after a fatal error. So on x86, we can 589 // only walk stack if %ebp is used as frame pointer; on ia64, it's not 590 // possible to walk C stack without having the unwind table. 591 static bool is_first_C_frame(frame *fr); 592 static frame get_sender_for_C_frame(frame *fr); 593 594 // return current frame. pc() and sp() are set to NULL on failure. 595 static frame current_frame(); 596 597 static void print_hex_dump(outputStream* st, address start, address end, int unitsize); 598 599 // returns a string to describe the exception/signal; 600 // returns NULL if exception_code is not an OS exception/signal. 601 static const char* exception_name(int exception_code, char* buf, size_t buflen); 602 603 // Returns native Java library, loads if necessary 604 static void* native_java_library(); 605 606 // Fills in path to jvm.dll/libjvm.so (used by the Disassembler) 607 static void jvm_path(char *buf, jint buflen); 608 609 // Returns true if we are running in a headless jre. 610 static bool is_headless_jre(); 611 612 // JNI names 613 static void print_jni_name_prefix_on(outputStream* st, int args_size); 614 static void print_jni_name_suffix_on(outputStream* st, int args_size); 615 616 // File conventions 617 static const char* file_separator(); 618 static const char* line_separator(); 619 static const char* path_separator(); 620 621 // Init os specific system properties values 622 static void init_system_properties_values(); 623 624 // IO operations, non-JVM_ version. 625 static int stat(const char* path, struct stat* sbuf); 626 static bool dir_is_empty(const char* path); 627 628 // IO operations on binary files 629 static int create_binary_file(const char* path, bool rewrite_existing); 630 static jlong current_file_offset(int fd); 631 static jlong seek_to_file_offset(int fd, jlong offset); 632 633 // Thread Local Storage 634 static int allocate_thread_local_storage(); 635 static void thread_local_storage_at_put(int index, void* value); 636 static void* thread_local_storage_at(int index); 637 static void free_thread_local_storage(int index); 638 639 // Stack walk 640 static address get_caller_pc(int n = 0); 641 642 // General allocation (must be MT-safe) 643 static void* malloc (size_t size, MEMFLAGS flags, address caller_pc = 0); 644 static void* realloc (void *memblock, size_t size, MEMFLAGS flags, address caller_pc = 0); 645 static void free (void *memblock, MEMFLAGS flags = mtNone); 646 static bool check_heap(bool force = false); // verify C heap integrity 647 static char* strdup(const char *, MEMFLAGS flags = mtInternal); // Like strdup 648 649 #ifndef PRODUCT 650 static julong num_mallocs; // # of calls to malloc/realloc 651 static julong alloc_bytes; // # of bytes allocated 652 static julong num_frees; // # of calls to free 653 static julong free_bytes; // # of bytes freed 654 #endif 655 656 // SocketInterface (ex HPI SocketInterface ) 657 static int socket(int domain, int type, int protocol); 658 static int socket_close(int fd); 659 static int socket_shutdown(int fd, int howto); 660 static int recv(int fd, char* buf, size_t nBytes, uint flags); 661 static int send(int fd, char* buf, size_t nBytes, uint flags); 662 static int raw_send(int fd, char* buf, size_t nBytes, uint flags); 663 static int timeout(int fd, long timeout); 664 static int listen(int fd, int count); 665 static int connect(int fd, struct sockaddr* him, socklen_t len); 666 static int bind(int fd, struct sockaddr* him, socklen_t len); 667 static int accept(int fd, struct sockaddr* him, socklen_t* len); 668 static int recvfrom(int fd, char* buf, size_t nbytes, uint flags, 669 struct sockaddr* from, socklen_t* fromlen); 670 static int get_sock_name(int fd, struct sockaddr* him, socklen_t* len); 671 static int sendto(int fd, char* buf, size_t len, uint flags, 672 struct sockaddr* to, socklen_t tolen); 673 static int socket_available(int fd, jint* pbytes); 674 675 static int get_sock_opt(int fd, int level, int optname, 676 char* optval, socklen_t* optlen); 677 static int set_sock_opt(int fd, int level, int optname, 678 const char* optval, socklen_t optlen); 679 static int get_host_name(char* name, int namelen); 680 681 static struct hostent* get_host_by_name(char* name); 682 683 // Support for signals (see JVM_RaiseSignal, JVM_RegisterSignal) 684 static void signal_init(); 685 static void signal_init_pd(); 686 static void signal_notify(int signal_number); 687 static void* signal(int signal_number, void* handler); 688 static void signal_raise(int signal_number); 689 static int signal_wait(); 690 static int signal_lookup(); 691 static void* user_handler(); 692 static void terminate_signal_thread(); 693 static int sigexitnum_pd(); 694 695 // random number generation 696 static long random(); // return 32bit pseudorandom number 697 static void init_random(long initval); // initialize random sequence 698 699 // Structured OS Exception support 700 static void os_exception_wrapper(java_call_t f, JavaValue* value, methodHandle* method, JavaCallArguments* args, Thread* thread); 701 702 // On Windows this will create an actual minidump, on Linux/Solaris it will simply check core dump limits 703 static void check_or_create_dump(void* exceptionRecord, void* contextRecord, char* buffer, size_t bufferSize); 704 705 // Get the default path to the core file 706 // Returns the length of the string 707 static int get_core_path(char* buffer, size_t bufferSize); 708 709 // JVMTI & JVM monitoring and management support 710 // The thread_cpu_time() and current_thread_cpu_time() are only 711 // supported if is_thread_cpu_time_supported() returns true. 712 // They are not supported on Solaris T1. 713 714 // Thread CPU Time - return the fast estimate on a platform 715 // On Solaris - call gethrvtime (fast) - user time only 716 // On Linux - fast clock_gettime where available - user+sys 717 // - otherwise: very slow /proc fs - user+sys 718 // On Windows - GetThreadTimes - user+sys 719 static jlong current_thread_cpu_time(); 720 static jlong thread_cpu_time(Thread* t); 721 722 // Thread CPU Time with user_sys_cpu_time parameter. 723 // 724 // If user_sys_cpu_time is true, user+sys time is returned. 725 // Otherwise, only user time is returned 726 static jlong current_thread_cpu_time(bool user_sys_cpu_time); 727 static jlong thread_cpu_time(Thread* t, bool user_sys_cpu_time); 728 729 // Return a bunch of info about the timers. 730 // Note that the returned info for these two functions may be different 731 // on some platforms 732 static void current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr); 733 static void thread_cpu_time_info(jvmtiTimerInfo *info_ptr); 734 735 static bool is_thread_cpu_time_supported(); 736 737 // System loadavg support. Returns -1 if load average cannot be obtained. 738 static int loadavg(double loadavg[], int nelem); 739 740 // Hook for os specific jvm options that we don't want to abort on seeing 741 static bool obsolete_option(const JavaVMOption *option); 742 743 // Extensions 744 #include "runtime/os_ext.hpp" 745 746 public: 747 class CrashProtectionCallback : public StackObj { 748 public: 749 virtual void call() = 0; 750 }; 751 752 // Platform dependent stuff 753 #ifdef TARGET_OS_FAMILY_linux 754 # include "os_linux.hpp" 755 # include "os_posix.hpp" 756 #endif 757 #ifdef TARGET_OS_FAMILY_solaris 758 # include "os_solaris.hpp" 759 # include "os_posix.hpp" 760 #endif 761 #ifdef TARGET_OS_FAMILY_windows 762 # include "os_windows.hpp" 763 #endif 764 #ifdef TARGET_OS_FAMILY_bsd 765 # include "os_posix.hpp" 766 # include "os_bsd.hpp" 767 #endif 768 #ifdef TARGET_OS_ARCH_linux_x86 769 # include "os_linux_x86.hpp" 770 #endif 771 #ifdef TARGET_OS_ARCH_linux_sparc 772 # include "os_linux_sparc.hpp" 773 #endif 774 #ifdef TARGET_OS_ARCH_linux_zero 775 # include "os_linux_zero.hpp" 776 #endif 777 #ifdef TARGET_OS_ARCH_solaris_x86 778 # include "os_solaris_x86.hpp" 779 #endif 780 #ifdef TARGET_OS_ARCH_solaris_sparc 781 # include "os_solaris_sparc.hpp" 782 #endif 783 #ifdef TARGET_OS_ARCH_windows_x86 784 # include "os_windows_x86.hpp" 785 #endif 786 #ifdef TARGET_OS_ARCH_linux_arm 787 # include "os_linux_arm.hpp" 788 #endif 789 #ifdef TARGET_OS_ARCH_linux_ppc 790 # include "os_linux_ppc.hpp" 791 #endif 792 #ifdef TARGET_OS_ARCH_bsd_x86 793 # include "os_bsd_x86.hpp" 794 #endif 795 #ifdef TARGET_OS_ARCH_bsd_zero 796 # include "os_bsd_zero.hpp" 797 #endif 798 799 public: 800 // debugging support (mostly used by debug.cpp but also fatal error handler) 801 static bool find(address pc, outputStream* st = tty); // OS specific function to make sense out of an address 802 803 static bool dont_yield(); // when true, JVM_Yield() is nop 804 static void print_statistics(); 805 806 // Thread priority helpers (implemented in OS-specific part) 807 static OSReturn set_native_priority(Thread* thread, int native_prio); 808 static OSReturn get_native_priority(const Thread* const thread, int* priority_ptr); 809 static int java_to_os_priority[CriticalPriority + 1]; 810 // Hint to the underlying OS that a task switch would not be good. 811 // Void return because it's a hint and can fail. 812 static void hint_no_preempt(); 813 814 // Used at creation if requested by the diagnostic flag PauseAtStartup. 815 // Causes the VM to wait until an external stimulus has been applied 816 // (for Unix, that stimulus is a signal, for Windows, an external 817 // ResumeThread call) 818 static void pause(); 819 820 // Builds a platform dependent Agent_OnLoad_<libname> function name 821 // which is used to find statically linked in agents. 822 static char* build_agent_function_name(const char *sym, const char *cname, 823 bool is_absolute_path); 824 825 class SuspendedThreadTaskContext { 826 public: 827 SuspendedThreadTaskContext(Thread* thread, void *ucontext) : _thread(thread), _ucontext(ucontext) {} 828 Thread* thread() const { return _thread; } 829 void* ucontext() const { return _ucontext; } 830 private: 831 Thread* _thread; 832 void* _ucontext; 833 }; 834 835 class SuspendedThreadTask { 836 public: 837 SuspendedThreadTask(Thread* thread) : _thread(thread), _done(false) {} 838 virtual ~SuspendedThreadTask() {} 839 void run(); 840 bool is_done() { return _done; } 841 virtual void do_task(const SuspendedThreadTaskContext& context) = 0; 842 protected: 843 private: 844 void internal_do_task(); 845 Thread* _thread; 846 bool _done; 847 }; 848 849 #ifndef TARGET_OS_FAMILY_windows 850 // Suspend/resume support 851 // Protocol: 852 // 853 // a thread starts in SR_RUNNING 854 // 855 // SR_RUNNING can go to 856 // * SR_SUSPEND_REQUEST when the WatcherThread wants to suspend it 857 // SR_SUSPEND_REQUEST can go to 858 // * SR_RUNNING if WatcherThread decides it waited for SR_SUSPENDED too long (timeout) 859 // * SR_SUSPENDED if the stopped thread receives the signal and switches state 860 // SR_SUSPENDED can go to 861 // * SR_WAKEUP_REQUEST when the WatcherThread has done the work and wants to resume 862 // SR_WAKEUP_REQUEST can go to 863 // * SR_RUNNING when the stopped thread receives the signal 864 // * SR_WAKEUP_REQUEST on timeout (resend the signal and try again) 865 class SuspendResume { 866 public: 867 enum State { 868 SR_RUNNING, 869 SR_SUSPEND_REQUEST, 870 SR_SUSPENDED, 871 SR_WAKEUP_REQUEST 872 }; 873 874 private: 875 volatile State _state; 876 877 private: 878 /* try to switch state from state "from" to state "to" 879 * returns the state set after the method is complete 880 */ 881 State switch_state(State from, State to); 882 883 public: 884 SuspendResume() : _state(SR_RUNNING) { } 885 886 State state() const { return _state; } 887 888 State request_suspend() { 889 return switch_state(SR_RUNNING, SR_SUSPEND_REQUEST); 890 } 891 892 State cancel_suspend() { 893 return switch_state(SR_SUSPEND_REQUEST, SR_RUNNING); 894 } 895 896 State suspended() { 897 return switch_state(SR_SUSPEND_REQUEST, SR_SUSPENDED); 898 } 899 900 State request_wakeup() { 901 return switch_state(SR_SUSPENDED, SR_WAKEUP_REQUEST); 902 } 903 904 State running() { 905 return switch_state(SR_WAKEUP_REQUEST, SR_RUNNING); 906 } 907 908 bool is_running() const { 909 return _state == SR_RUNNING; 910 } 911 912 bool is_suspend_request() const { 913 return _state == SR_SUSPEND_REQUEST; 914 } 915 916 bool is_suspended() const { 917 return _state == SR_SUSPENDED; 918 } 919 }; 920 #endif 921 922 923 protected: 924 static long _rand_seed; // seed for random number generator 925 static int _processor_count; // number of processors 926 927 static char* format_boot_path(const char* format_string, 928 const char* home, 929 int home_len, 930 char fileSep, 931 char pathSep); 932 static bool set_boot_path(char fileSep, char pathSep); 933 static char** split_path(const char* path, int* n); 934 935 }; 936 937 // Note that "PAUSE" is almost always used with synchronization 938 // so arguably we should provide Atomic::SpinPause() instead 939 // of the global SpinPause() with C linkage. 940 // It'd also be eligible for inlining on many platforms. 941 942 extern "C" int SpinPause(); 943 944 #endif // SHARE_VM_RUNTIME_OS_HPP