1 /* 2 * Copyright (c) 1997, 2016, 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 "prims/jvm.h" 30 #include "runtime/extendedPC.hpp" 31 #include "runtime/handles.hpp" 32 #include "utilities/macros.hpp" 33 #ifndef _WINDOWS 34 # include <setjmp.h> 35 #endif 36 #ifdef __APPLE__ 37 # include <mach/mach_time.h> 38 #endif 39 40 class AgentLibrary; 41 42 // os defines the interface to operating system; this includes traditional 43 // OS services (time, I/O) as well as other functionality with system- 44 // dependent code. 45 46 typedef void (*dll_func)(...); 47 48 class Thread; 49 class JavaThread; 50 class Event; 51 class DLL; 52 class FileHandle; 53 class NativeCallStack; 54 55 template<class E> class GrowableArray; 56 57 // %%%%% Moved ThreadState, START_FN, OSThread to new osThread.hpp. -- Rose 58 59 // Platform-independent error return values from OS functions 60 enum OSReturn { 61 OS_OK = 0, // Operation was successful 62 OS_ERR = -1, // Operation failed 63 OS_INTRPT = -2, // Operation was interrupted 64 OS_TIMEOUT = -3, // Operation timed out 65 OS_NOMEM = -5, // Operation failed for lack of memory 66 OS_NORESOURCE = -6 // Operation failed for lack of nonmemory resource 67 }; 68 69 enum ThreadPriority { // JLS 20.20.1-3 70 NoPriority = -1, // Initial non-priority value 71 MinPriority = 1, // Minimum priority 72 NormPriority = 5, // Normal (non-daemon) priority 73 NearMaxPriority = 9, // High priority, used for VMThread 74 MaxPriority = 10, // Highest priority, used for WatcherThread 75 // ensures that VMThread doesn't starve profiler 76 CriticalPriority = 11 // Critical thread priority 77 }; 78 79 // Executable parameter flag for os::commit_memory() and 80 // os::commit_memory_or_exit(). 81 const bool ExecMem = true; 82 83 // Typedef for structured exception handling support 84 typedef void (*java_call_t)(JavaValue* value, const methodHandle& method, JavaCallArguments* args, Thread* thread); 85 86 class MallocTracker; 87 88 class os: AllStatic { 89 friend class VMStructs; 90 friend class JVMCIVMStructs; 91 friend class MallocTracker; 92 public: 93 enum { page_sizes_max = 9 }; // Size of _page_sizes array (8 plus a sentinel) 94 95 private: 96 static OSThread* _starting_thread; 97 static address _polling_page; 98 static volatile int32_t * _mem_serialize_page; 99 static uintptr_t _serialize_page_mask; 100 public: 101 static size_t _page_sizes[page_sizes_max]; 102 103 private: 104 static void init_page_sizes(size_t default_page_size) { 105 _page_sizes[0] = default_page_size; 106 _page_sizes[1] = 0; // sentinel 107 } 108 109 static char* pd_reserve_memory(size_t bytes, char* addr = 0, 110 size_t alignment_hint = 0); 111 static char* pd_attempt_reserve_memory_at(size_t bytes, char* addr); 112 static void pd_split_reserved_memory(char *base, size_t size, 113 size_t split, bool realloc); 114 static bool pd_commit_memory(char* addr, size_t bytes, bool executable); 115 static bool pd_commit_memory(char* addr, size_t size, size_t alignment_hint, 116 bool executable); 117 // Same as pd_commit_memory() that either succeeds or calls 118 // vm_exit_out_of_memory() with the specified mesg. 119 static void pd_commit_memory_or_exit(char* addr, size_t bytes, 120 bool executable, const char* mesg); 121 static void pd_commit_memory_or_exit(char* addr, size_t size, 122 size_t alignment_hint, 123 bool executable, const char* mesg); 124 static bool pd_uncommit_memory(char* addr, size_t bytes); 125 static bool pd_release_memory(char* addr, size_t bytes); 126 127 static char* pd_map_memory(int fd, const char* file_name, size_t file_offset, 128 char *addr, size_t bytes, bool read_only = false, 129 bool allow_exec = false); 130 static char* pd_remap_memory(int fd, const char* file_name, size_t file_offset, 131 char *addr, size_t bytes, bool read_only, 132 bool allow_exec); 133 static bool pd_unmap_memory(char *addr, size_t bytes); 134 static void pd_free_memory(char *addr, size_t bytes, size_t alignment_hint); 135 static void pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint); 136 137 static size_t page_size_for_region(size_t region_size, size_t min_pages, bool must_be_aligned); 138 139 // Get summary strings for system information in buffer provided 140 static void get_summary_cpu_info(char* buf, size_t buflen); 141 static void get_summary_os_info(char* buf, size_t buflen); 142 143 static void initialize_initial_active_processor_count(); 144 public: 145 static void init(void); // Called before command line parsing 146 static void init_before_ergo(void); // Called after command line parsing 147 // before VM ergonomics processing. 148 static jint init_2(void); // Called after command line parsing 149 // and VM ergonomics processing 150 static void init_globals(void) { // Called from init_globals() in init.cpp 151 init_globals_ext(); 152 } 153 154 // File names are case-insensitive on windows only 155 // Override me as needed 156 static int file_name_strcmp(const char* s1, const char* s2); 157 158 // unset environment variable 159 static bool unsetenv(const char* name); 160 161 static bool have_special_privileges(); 162 163 static jlong javaTimeMillis(); 164 static jlong javaTimeNanos(); 165 static void javaTimeNanos_info(jvmtiTimerInfo *info_ptr); 166 static void javaTimeSystemUTC(jlong &seconds, jlong &nanos); 167 static void run_periodic_checks(); 168 static bool supports_monotonic_clock(); 169 170 // Returns the elapsed time in seconds since the vm started. 171 static double elapsedTime(); 172 173 // Returns real time in seconds since an arbitrary point 174 // in the past. 175 static bool getTimesSecs(double* process_real_time, 176 double* process_user_time, 177 double* process_system_time); 178 179 // Interface to the performance counter 180 static jlong elapsed_counter(); 181 static jlong elapsed_frequency(); 182 183 // The "virtual time" of a thread is the amount of time a thread has 184 // actually run. The first function indicates whether the OS supports 185 // this functionality for the current thread, and if so: 186 // * the second enables vtime tracking (if that is required). 187 // * the third tells whether vtime is enabled. 188 // * the fourth returns the elapsed virtual time for the current 189 // thread. 190 static bool supports_vtime(); 191 static bool enable_vtime(); 192 static bool vtime_enabled(); 193 static double elapsedVTime(); 194 195 // Return current local time in a string (YYYY-MM-DD HH:MM:SS). 196 // It is MT safe, but not async-safe, as reading time zone 197 // information may require a lock on some platforms. 198 static char* local_time_string(char *buf, size_t buflen); 199 static struct tm* localtime_pd (const time_t* clock, struct tm* res); 200 // Fill in buffer with current local time as an ISO-8601 string. 201 // E.g., YYYY-MM-DDThh:mm:ss.mmm+zzzz. 202 // Returns buffer, or NULL if it failed. 203 static char* iso8601_time(char* buffer, size_t buffer_length); 204 205 // Interface for detecting multiprocessor system 206 static inline bool is_MP() { 207 // During bootstrap if _processor_count is not yet initialized 208 // we claim to be MP as that is safest. If any platform has a 209 // stub generator that might be triggered in this phase and for 210 // which being declared MP when in fact not, is a problem - then 211 // the bootstrap routine for the stub generator needs to check 212 // the processor count directly and leave the bootstrap routine 213 // in place until called after initialization has ocurred. 214 return (_processor_count != 1) || AssumeMP; 215 } 216 static julong available_memory(); 217 static julong physical_memory(); 218 static bool has_allocatable_memory_limit(julong* limit); 219 static bool is_server_class_machine(); 220 221 // number of CPUs 222 static int processor_count() { 223 return _processor_count; 224 } 225 static void set_processor_count(int count) { _processor_count = count; } 226 227 // Returns the number of CPUs this process is currently allowed to run on. 228 // Note that on some OSes this can change dynamically. 229 static int active_processor_count(); 230 231 // At startup the number of active CPUs this process is allowed to run on. 232 // This value does not change dynamically. May be different from active_processor_count(). 233 static int initial_active_processor_count() { 234 assert(_initial_active_processor_count > 0, "Initial active processor count not set yet."); 235 return _initial_active_processor_count; 236 } 237 238 // Bind processes to processors. 239 // This is a two step procedure: 240 // first you generate a distribution of processes to processors, 241 // then you bind processes according to that distribution. 242 // Compute a distribution for number of processes to processors. 243 // Stores the processor id's into the distribution array argument. 244 // Returns true if it worked, false if it didn't. 245 static bool distribute_processes(uint length, uint* distribution); 246 // Binds the current process to a processor. 247 // Returns true if it worked, false if it didn't. 248 static bool bind_to_processor(uint processor_id); 249 250 // Give a name to the current thread. 251 static void set_native_thread_name(const char *name); 252 253 // Interface for stack banging (predetect possible stack overflow for 254 // exception processing) There are guard pages, and above that shadow 255 // pages for stack overflow checking. 256 static bool uses_stack_guard_pages(); 257 static bool must_commit_stack_guard_pages(); 258 static void map_stack_shadow_pages(address sp); 259 static bool stack_shadow_pages_available(Thread *thread, const methodHandle& method, address sp); 260 261 // OS interface to Virtual Memory 262 263 // Return the default page size. 264 static int vm_page_size(); 265 266 // Returns the page size to use for a region of memory. 267 // region_size / min_pages will always be greater than or equal to the 268 // returned value. The returned value will divide region_size. 269 static size_t page_size_for_region_aligned(size_t region_size, size_t min_pages); 270 271 // Returns the page size to use for a region of memory. 272 // region_size / min_pages will always be greater than or equal to the 273 // returned value. The returned value might not divide region_size. 274 static size_t page_size_for_region_unaligned(size_t region_size, size_t min_pages); 275 276 // Return the largest page size that can be used 277 static size_t max_page_size() { 278 // The _page_sizes array is sorted in descending order. 279 return _page_sizes[0]; 280 } 281 282 // Methods for tracing page sizes returned by the above method. 283 // The region_{min,max}_size parameters should be the values 284 // passed to page_size_for_region() and page_size should be the result of that 285 // call. The (optional) base and size parameters should come from the 286 // ReservedSpace base() and size() methods. 287 static void trace_page_sizes(const char* str, const size_t* page_sizes, int count); 288 static void trace_page_sizes(const char* str, 289 const size_t region_min_size, 290 const size_t region_max_size, 291 const size_t page_size, 292 const char* base, 293 const size_t size); 294 static void trace_page_sizes_for_requested_size(const char* str, 295 const size_t requested_size, 296 const size_t page_size, 297 const size_t alignment, 298 const char* base, 299 const size_t size); 300 301 static int vm_allocation_granularity(); 302 static char* reserve_memory(size_t bytes, char* addr = 0, 303 size_t alignment_hint = 0); 304 static char* reserve_memory(size_t bytes, char* addr, 305 size_t alignment_hint, MEMFLAGS flags); 306 static char* reserve_memory_aligned(size_t size, size_t alignment); 307 static char* attempt_reserve_memory_at(size_t bytes, char* addr); 308 static void split_reserved_memory(char *base, size_t size, 309 size_t split, bool realloc); 310 static bool commit_memory(char* addr, size_t bytes, bool executable); 311 static bool commit_memory(char* addr, size_t size, size_t alignment_hint, 312 bool executable); 313 // Same as commit_memory() that either succeeds or calls 314 // vm_exit_out_of_memory() with the specified mesg. 315 static void commit_memory_or_exit(char* addr, size_t bytes, 316 bool executable, const char* mesg); 317 static void commit_memory_or_exit(char* addr, size_t size, 318 size_t alignment_hint, 319 bool executable, const char* mesg); 320 static bool uncommit_memory(char* addr, size_t bytes); 321 static bool release_memory(char* addr, size_t bytes); 322 323 // Touch memory pages that cover the memory range from start to end (exclusive) 324 // to make the OS back the memory range with actual memory. 325 // Current implementation may not touch the last page if unaligned addresses 326 // are passed. 327 static void pretouch_memory(void* start, void* end); 328 329 enum ProtType { MEM_PROT_NONE, MEM_PROT_READ, MEM_PROT_RW, MEM_PROT_RWX }; 330 static bool protect_memory(char* addr, size_t bytes, ProtType prot, 331 bool is_committed = true); 332 333 static bool guard_memory(char* addr, size_t bytes); 334 static bool unguard_memory(char* addr, size_t bytes); 335 static bool create_stack_guard_pages(char* addr, size_t bytes); 336 static bool pd_create_stack_guard_pages(char* addr, size_t bytes); 337 static bool remove_stack_guard_pages(char* addr, size_t bytes); 338 339 static char* map_memory(int fd, const char* file_name, size_t file_offset, 340 char *addr, size_t bytes, bool read_only = false, 341 bool allow_exec = false); 342 static char* remap_memory(int fd, const char* file_name, size_t file_offset, 343 char *addr, size_t bytes, bool read_only, 344 bool allow_exec); 345 static bool unmap_memory(char *addr, size_t bytes); 346 static void free_memory(char *addr, size_t bytes, size_t alignment_hint); 347 static void realign_memory(char *addr, size_t bytes, size_t alignment_hint); 348 349 // NUMA-specific interface 350 static bool numa_has_static_binding(); 351 static bool numa_has_group_homing(); 352 static void numa_make_local(char *addr, size_t bytes, int lgrp_hint); 353 static void numa_make_global(char *addr, size_t bytes); 354 static size_t numa_get_groups_num(); 355 static size_t numa_get_leaf_groups(int *ids, size_t size); 356 static bool numa_topology_changed(); 357 static int numa_get_group_id(); 358 359 // Page manipulation 360 struct page_info { 361 size_t size; 362 int lgrp_id; 363 }; 364 static bool get_page_info(char *start, page_info* info); 365 static char* scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found); 366 367 static char* non_memory_address_word(); 368 // reserve, commit and pin the entire memory region 369 static char* reserve_memory_special(size_t size, size_t alignment, 370 char* addr, bool executable); 371 static bool release_memory_special(char* addr, size_t bytes); 372 static void large_page_init(); 373 static size_t large_page_size(); 374 static bool can_commit_large_page_memory(); 375 static bool can_execute_large_page_memory(); 376 377 // OS interface to polling page 378 static address get_polling_page() { return _polling_page; } 379 static void set_polling_page(address page) { _polling_page = page; } 380 static bool is_poll_address(address addr) { return addr >= _polling_page && addr < (_polling_page + os::vm_page_size()); } 381 static void make_polling_page_unreadable(); 382 static void make_polling_page_readable(); 383 384 // Routines used to serialize the thread state without using membars 385 static void serialize_thread_states(); 386 387 // Since we write to the serialize page from every thread, we 388 // want stores to be on unique cache lines whenever possible 389 // in order to minimize CPU cross talk. We pre-compute the 390 // amount to shift the thread* to make this offset unique to 391 // each thread. 392 static int get_serialize_page_shift_count() { 393 return SerializePageShiftCount; 394 } 395 396 static void set_serialize_page_mask(uintptr_t mask) { 397 _serialize_page_mask = mask; 398 } 399 400 static unsigned int get_serialize_page_mask() { 401 return _serialize_page_mask; 402 } 403 404 static void set_memory_serialize_page(address page); 405 406 static address get_memory_serialize_page() { 407 return (address)_mem_serialize_page; 408 } 409 410 static inline void write_memory_serialize_page(JavaThread *thread) { 411 uintptr_t page_offset = ((uintptr_t)thread >> 412 get_serialize_page_shift_count()) & 413 get_serialize_page_mask(); 414 *(volatile int32_t *)((uintptr_t)_mem_serialize_page+page_offset) = 1; 415 } 416 417 static bool is_memory_serialize_page(JavaThread *thread, address addr) { 418 if (UseMembar) return false; 419 // Previously this function calculated the exact address of this 420 // thread's serialize page, and checked if the faulting address 421 // was equal. However, some platforms mask off faulting addresses 422 // to the page size, so now we just check that the address is 423 // within the page. This makes the thread argument unnecessary, 424 // but we retain the NULL check to preserve existing behavior. 425 if (thread == NULL) return false; 426 address page = (address) _mem_serialize_page; 427 return addr >= page && addr < (page + os::vm_page_size()); 428 } 429 430 static void block_on_serialize_page_trap(); 431 432 // threads 433 434 enum ThreadType { 435 vm_thread, 436 cgc_thread, // Concurrent GC thread 437 pgc_thread, // Parallel GC thread 438 java_thread, 439 compiler_thread, 440 watcher_thread, 441 os_thread 442 }; 443 444 static bool create_thread(Thread* thread, 445 ThreadType thr_type, 446 size_t req_stack_size = 0); 447 static bool create_main_thread(JavaThread* thread); 448 static bool create_attached_thread(JavaThread* thread); 449 static void pd_start_thread(Thread* thread); 450 static void start_thread(Thread* thread); 451 452 static void initialize_thread(Thread* thr); 453 static void free_thread(OSThread* osthread); 454 455 // thread id on Linux/64bit is 64bit, on Windows and Solaris, it's 32bit 456 static intx current_thread_id(); 457 static int current_process_id(); 458 static int sleep(Thread* thread, jlong ms, bool interruptable); 459 // Short standalone OS sleep suitable for slow path spin loop. 460 // Ignores Thread.interrupt() (so keep it short). 461 // ms = 0, will sleep for the least amount of time allowed by the OS. 462 static void naked_short_sleep(jlong ms); 463 static void infinite_sleep(); // never returns, use with CAUTION 464 static void naked_yield () ; 465 static OSReturn set_priority(Thread* thread, ThreadPriority priority); 466 static OSReturn get_priority(const Thread* const thread, ThreadPriority& priority); 467 468 static void interrupt(Thread* thread); 469 static bool is_interrupted(Thread* thread, bool clear_interrupted); 470 471 static int pd_self_suspend_thread(Thread* thread); 472 473 static ExtendedPC fetch_frame_from_context(const void* ucVoid, intptr_t** sp, intptr_t** fp); 474 static frame fetch_frame_from_context(const void* ucVoid); 475 static frame fetch_frame_from_ucontext(Thread* thread, void* ucVoid); 476 477 static ExtendedPC get_thread_pc(Thread *thread); 478 static void breakpoint(); 479 static bool start_debugging(char *buf, int buflen); 480 481 static address current_stack_pointer(); 482 static address current_stack_base(); 483 static size_t current_stack_size(); 484 485 static void verify_stack_alignment() PRODUCT_RETURN; 486 487 static bool message_box(const char* title, const char* message); 488 static char* do_you_want_to_debug(const char* message); 489 490 // run cmd in a separate process and return its exit code; or -1 on failures 491 static int fork_and_exec(char *cmd); 492 493 // Call ::exit() on all platforms but Windows 494 static void exit(int num); 495 496 // Terminate the VM, but don't exit the process 497 static void shutdown(); 498 499 // Terminate with an error. Default is to generate a core file on platforms 500 // that support such things. This calls shutdown() and then aborts. 501 static void abort(bool dump_core, void *siginfo, const void *context); 502 static void abort(bool dump_core = true); 503 504 // Die immediately, no exit hook, no abort hook, no cleanup. 505 static void die(); 506 507 // File i/o operations 508 static const int default_file_open_flags(); 509 static int open(const char *path, int oflag, int mode); 510 static FILE* open(int fd, const char* mode); 511 static int close(int fd); 512 static jlong lseek(int fd, jlong offset, int whence); 513 static char* native_path(char *path); 514 static int ftruncate(int fd, jlong length); 515 static int fsync(int fd); 516 static int available(int fd, jlong *bytes); 517 static int get_fileno(FILE* fp); 518 static void flockfile(FILE* fp); 519 static void funlockfile(FILE* fp); 520 521 static int compare_file_modified_times(const char* file1, const char* file2); 522 523 //File i/o operations 524 525 static size_t read(int fd, void *buf, unsigned int nBytes); 526 static size_t read_at(int fd, void *buf, unsigned int nBytes, jlong offset); 527 static size_t restartable_read(int fd, void *buf, unsigned int nBytes); 528 static size_t write(int fd, const void *buf, unsigned int nBytes); 529 530 // Reading directories. 531 static DIR* opendir(const char* dirname); 532 static int readdir_buf_size(const char *path); 533 static struct dirent* readdir(DIR* dirp, dirent* dbuf); 534 static int closedir(DIR* dirp); 535 536 // Dynamic library extension 537 static const char* dll_file_extension(); 538 539 static const char* get_temp_directory(); 540 static const char* get_current_directory(char *buf, size_t buflen); 541 542 // Builds a platform-specific full library path given a ld path and lib name 543 // Returns true if buffer contains full path to existing file, false otherwise 544 static bool dll_build_name(char* buffer, size_t size, 545 const char* pathname, const char* fname); 546 547 // Symbol lookup, find nearest function name; basically it implements 548 // dladdr() for all platforms. Name of the nearest function is copied 549 // to buf. Distance from its base address is optionally returned as offset. 550 // If function name is not found, buf[0] is set to '\0' and offset is 551 // set to -1 (if offset is non-NULL). 552 static bool dll_address_to_function_name(address addr, char* buf, 553 int buflen, int* offset, 554 bool demangle = true); 555 556 // Locate DLL/DSO. On success, full path of the library is copied to 557 // buf, and offset is optionally set to be the distance between addr 558 // and the library's base address. On failure, buf[0] is set to '\0' 559 // and offset is set to -1 (if offset is non-NULL). 560 static bool dll_address_to_library_name(address addr, char* buf, 561 int buflen, int* offset); 562 563 // Find out whether the pc is in the static code for jvm.dll/libjvm.so. 564 static bool address_is_in_vm(address addr); 565 566 // Loads .dll/.so and 567 // in case of error it checks if .dll/.so was built for the 568 // same architecture as HotSpot is running on 569 static void* dll_load(const char *name, char *ebuf, int ebuflen); 570 571 // lookup symbol in a shared library 572 static void* dll_lookup(void* handle, const char* name); 573 574 // Unload library 575 static void dll_unload(void *lib); 576 577 // Callback for loaded module information 578 // Input parameters: 579 // char* module_file_name, 580 // address module_base_addr, 581 // address module_top_addr, 582 // void* param 583 typedef int (*LoadedModulesCallbackFunc)(const char *, address, address, void *); 584 585 static int get_loaded_modules_info(LoadedModulesCallbackFunc callback, void *param); 586 587 // Return the handle of this process 588 static void* get_default_process_handle(); 589 590 // Check for static linked agent library 591 static bool find_builtin_agent(AgentLibrary *agent_lib, const char *syms[], 592 size_t syms_len); 593 594 // Find agent entry point 595 static void *find_agent_function(AgentLibrary *agent_lib, bool check_lib, 596 const char *syms[], size_t syms_len); 597 598 // Write to stream 599 static int log_vsnprintf(char* buf, size_t len, const char* fmt, va_list args) ATTRIBUTE_PRINTF(3, 0); 600 601 // Get host name in buffer provided 602 static bool get_host_name(char* buf, size_t buflen); 603 604 // Print out system information; they are called by fatal error handler. 605 // Output format may be different on different platforms. 606 static void print_os_info(outputStream* st); 607 static void print_os_info_brief(outputStream* st); 608 static void print_cpu_info(outputStream* st, char* buf, size_t buflen); 609 static void pd_print_cpu_info(outputStream* st, char* buf, size_t buflen); 610 static void print_summary_info(outputStream* st, char* buf, size_t buflen); 611 static void print_memory_info(outputStream* st); 612 static void print_dll_info(outputStream* st); 613 static void print_environment_variables(outputStream* st, const char** env_list); 614 static void print_context(outputStream* st, const void* context); 615 static void print_register_info(outputStream* st, const void* context); 616 static void print_siginfo(outputStream* st, const void* siginfo); 617 static void print_signal_handlers(outputStream* st, char* buf, size_t buflen); 618 static void print_date_and_time(outputStream* st, char* buf, size_t buflen); 619 620 static void print_location(outputStream* st, intptr_t x, bool verbose = false); 621 static size_t lasterror(char *buf, size_t len); 622 static int get_last_error(); 623 624 // Replacement for strerror(). 625 // Will return the english description of the error (e.g. "File not found", as 626 // suggested in the POSIX standard. 627 // Will return "Unknown error" for an unknown errno value. 628 // Will not attempt to localize the returned string. 629 // Will always return a valid string which is a static constant. 630 // Will not change the value of errno. 631 static const char* strerror(int e); 632 633 // Will return the literalized version of the given errno (e.g. "EINVAL" 634 // for EINVAL). 635 // Will return "Unknown error" for an unknown errno value. 636 // Will always return a valid string which is a static constant. 637 // Will not change the value of errno. 638 static const char* errno_name(int e); 639 640 // Determines whether the calling process is being debugged by a user-mode debugger. 641 static bool is_debugger_attached(); 642 643 // wait for a key press if PauseAtExit is set 644 static void wait_for_keypress_at_exit(void); 645 646 // The following two functions are used by fatal error handler to trace 647 // native (C) frames. They are not part of frame.hpp/frame.cpp because 648 // frame.hpp/cpp assume thread is JavaThread, and also because different 649 // OS/compiler may have different convention or provide different API to 650 // walk C frames. 651 // 652 // We don't attempt to become a debugger, so we only follow frames if that 653 // does not require a lookup in the unwind table, which is part of the binary 654 // file but may be unsafe to read after a fatal error. So on x86, we can 655 // only walk stack if %ebp is used as frame pointer; on ia64, it's not 656 // possible to walk C stack without having the unwind table. 657 static bool is_first_C_frame(frame *fr); 658 static frame get_sender_for_C_frame(frame *fr); 659 660 // return current frame. pc() and sp() are set to NULL on failure. 661 static frame current_frame(); 662 663 static void print_hex_dump(outputStream* st, address start, address end, int unitsize); 664 665 // returns a string to describe the exception/signal; 666 // returns NULL if exception_code is not an OS exception/signal. 667 static const char* exception_name(int exception_code, char* buf, size_t buflen); 668 669 // Returns the signal number (e.g. 11) for a given signal name (SIGSEGV). 670 static int get_signal_number(const char* signal_name); 671 672 // Returns native Java library, loads if necessary 673 static void* native_java_library(); 674 675 // Fills in path to jvm.dll/libjvm.so (used by the Disassembler) 676 static void jvm_path(char *buf, jint buflen); 677 678 // Returns true if we are running in a headless jre. 679 static bool is_headless_jre(); 680 681 // JNI names 682 static void print_jni_name_prefix_on(outputStream* st, int args_size); 683 static void print_jni_name_suffix_on(outputStream* st, int args_size); 684 685 // Init os specific system properties values 686 static void init_system_properties_values(); 687 688 // IO operations, non-JVM_ version. 689 static int stat(const char* path, struct stat* sbuf); 690 static bool dir_is_empty(const char* path); 691 692 // IO operations on binary files 693 static int create_binary_file(const char* path, bool rewrite_existing); 694 static jlong current_file_offset(int fd); 695 static jlong seek_to_file_offset(int fd, jlong offset); 696 697 // Retrieve native stack frames. 698 // Parameter: 699 // stack: an array to storage stack pointers. 700 // frames: size of above array. 701 // toSkip: number of stack frames to skip at the beginning. 702 // Return: number of stack frames captured. 703 static int get_native_stack(address* stack, int size, int toSkip = 0); 704 705 // General allocation (must be MT-safe) 706 static void* malloc (size_t size, MEMFLAGS flags, const NativeCallStack& stack); 707 static void* malloc (size_t size, MEMFLAGS flags); 708 static void* realloc (void *memblock, size_t size, MEMFLAGS flag, const NativeCallStack& stack); 709 static void* realloc (void *memblock, size_t size, MEMFLAGS flag); 710 711 static void free (void *memblock); 712 static char* strdup(const char *, MEMFLAGS flags = mtInternal); // Like strdup 713 // Like strdup, but exit VM when strdup() returns NULL 714 static char* strdup_check_oom(const char*, MEMFLAGS flags = mtInternal); 715 716 #ifndef PRODUCT 717 static julong num_mallocs; // # of calls to malloc/realloc 718 static julong alloc_bytes; // # of bytes allocated 719 static julong num_frees; // # of calls to free 720 static julong free_bytes; // # of bytes freed 721 #endif 722 723 // SocketInterface (ex HPI SocketInterface ) 724 static int socket(int domain, int type, int protocol); 725 static int socket_close(int fd); 726 static int recv(int fd, char* buf, size_t nBytes, uint flags); 727 static int send(int fd, char* buf, size_t nBytes, uint flags); 728 static int raw_send(int fd, char* buf, size_t nBytes, uint flags); 729 static int connect(int fd, struct sockaddr* him, socklen_t len); 730 static struct hostent* get_host_by_name(char* name); 731 732 // Support for signals (see JVM_RaiseSignal, JVM_RegisterSignal) 733 static void signal_init(); 734 static void signal_init_pd(); 735 static void signal_notify(int signal_number); 736 static void* signal(int signal_number, void* handler); 737 static void signal_raise(int signal_number); 738 static int signal_wait(); 739 static int signal_lookup(); 740 static void* user_handler(); 741 static void terminate_signal_thread(); 742 static int sigexitnum_pd(); 743 744 // random number generation 745 static long random(); // return 32bit pseudorandom number 746 static void init_random(long initval); // initialize random sequence 747 748 // Structured OS Exception support 749 static void os_exception_wrapper(java_call_t f, JavaValue* value, const methodHandle& method, JavaCallArguments* args, Thread* thread); 750 751 // On Posix compatible OS it will simply check core dump limits while on Windows 752 // it will check if dump file can be created. Check or prepare a core dump to be 753 // taken at a later point in the same thread in os::abort(). Use the caller 754 // provided buffer as a scratch buffer. The status message which will be written 755 // into the error log either is file location or a short error message, depending 756 // on the checking result. 757 static void check_dump_limit(char* buffer, size_t bufferSize); 758 759 // Get the default path to the core file 760 // Returns the length of the string 761 static int get_core_path(char* buffer, size_t bufferSize); 762 763 // JVMTI & JVM monitoring and management support 764 // The thread_cpu_time() and current_thread_cpu_time() are only 765 // supported if is_thread_cpu_time_supported() returns true. 766 // They are not supported on Solaris T1. 767 768 // Thread CPU Time - return the fast estimate on a platform 769 // On Solaris - call gethrvtime (fast) - user time only 770 // On Linux - fast clock_gettime where available - user+sys 771 // - otherwise: very slow /proc fs - user+sys 772 // On Windows - GetThreadTimes - user+sys 773 static jlong current_thread_cpu_time(); 774 static jlong thread_cpu_time(Thread* t); 775 776 // Thread CPU Time with user_sys_cpu_time parameter. 777 // 778 // If user_sys_cpu_time is true, user+sys time is returned. 779 // Otherwise, only user time is returned 780 static jlong current_thread_cpu_time(bool user_sys_cpu_time); 781 static jlong thread_cpu_time(Thread* t, bool user_sys_cpu_time); 782 783 // Return a bunch of info about the timers. 784 // Note that the returned info for these two functions may be different 785 // on some platforms 786 static void current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr); 787 static void thread_cpu_time_info(jvmtiTimerInfo *info_ptr); 788 789 static bool is_thread_cpu_time_supported(); 790 791 // System loadavg support. Returns -1 if load average cannot be obtained. 792 static int loadavg(double loadavg[], int nelem); 793 794 // Hook for os specific jvm options that we don't want to abort on seeing 795 static bool obsolete_option(const JavaVMOption *option); 796 797 // Amount beyond the callee frame size that we bang the stack. 798 static int extra_bang_size_in_bytes(); 799 800 static char** split_path(const char* path, int* n); 801 802 // Extensions 803 #include "runtime/os_ext.hpp" 804 805 public: 806 class CrashProtectionCallback : public StackObj { 807 public: 808 virtual void call() = 0; 809 }; 810 811 // Platform dependent stuff 812 #ifndef _WINDOWS 813 # include "os_posix.hpp" 814 #endif 815 #include OS_CPU_HEADER(os) 816 #include OS_HEADER(os) 817 818 #ifndef OS_NATIVE_THREAD_CREATION_FAILED_MSG 819 #define OS_NATIVE_THREAD_CREATION_FAILED_MSG "unable to create native thread: possibly out of memory or process/resource limits reached" 820 #endif 821 822 public: 823 #ifndef PLATFORM_PRINT_NATIVE_STACK 824 // No platform-specific code for printing the native stack. 825 static bool platform_print_native_stack(outputStream* st, const void* context, 826 char *buf, int buf_size) { 827 return false; 828 } 829 #endif 830 831 // debugging support (mostly used by debug.cpp but also fatal error handler) 832 static bool find(address pc, outputStream* st = tty); // OS specific function to make sense out of an address 833 834 static bool dont_yield(); // when true, JVM_Yield() is nop 835 static void print_statistics(); 836 837 // Thread priority helpers (implemented in OS-specific part) 838 static OSReturn set_native_priority(Thread* thread, int native_prio); 839 static OSReturn get_native_priority(const Thread* const thread, int* priority_ptr); 840 static int java_to_os_priority[CriticalPriority + 1]; 841 // Hint to the underlying OS that a task switch would not be good. 842 // Void return because it's a hint and can fail. 843 static void hint_no_preempt(); 844 static const char* native_thread_creation_failed_msg() { 845 return OS_NATIVE_THREAD_CREATION_FAILED_MSG; 846 } 847 848 // Used at creation if requested by the diagnostic flag PauseAtStartup. 849 // Causes the VM to wait until an external stimulus has been applied 850 // (for Unix, that stimulus is a signal, for Windows, an external 851 // ResumeThread call) 852 static void pause(); 853 854 // Builds a platform dependent Agent_OnLoad_<libname> function name 855 // which is used to find statically linked in agents. 856 static char* build_agent_function_name(const char *sym, const char *cname, 857 bool is_absolute_path); 858 859 class SuspendedThreadTaskContext { 860 public: 861 SuspendedThreadTaskContext(Thread* thread, void *ucontext) : _thread(thread), _ucontext(ucontext) {} 862 Thread* thread() const { return _thread; } 863 void* ucontext() const { return _ucontext; } 864 private: 865 Thread* _thread; 866 void* _ucontext; 867 }; 868 869 class SuspendedThreadTask { 870 public: 871 SuspendedThreadTask(Thread* thread) : _thread(thread), _done(false) {} 872 virtual ~SuspendedThreadTask() {} 873 void run(); 874 bool is_done() { return _done; } 875 virtual void do_task(const SuspendedThreadTaskContext& context) = 0; 876 protected: 877 private: 878 void internal_do_task(); 879 Thread* _thread; 880 bool _done; 881 }; 882 883 #ifndef _WINDOWS 884 // Suspend/resume support 885 // Protocol: 886 // 887 // a thread starts in SR_RUNNING 888 // 889 // SR_RUNNING can go to 890 // * SR_SUSPEND_REQUEST when the WatcherThread wants to suspend it 891 // SR_SUSPEND_REQUEST can go to 892 // * SR_RUNNING if WatcherThread decides it waited for SR_SUSPENDED too long (timeout) 893 // * SR_SUSPENDED if the stopped thread receives the signal and switches state 894 // SR_SUSPENDED can go to 895 // * SR_WAKEUP_REQUEST when the WatcherThread has done the work and wants to resume 896 // SR_WAKEUP_REQUEST can go to 897 // * SR_RUNNING when the stopped thread receives the signal 898 // * SR_WAKEUP_REQUEST on timeout (resend the signal and try again) 899 class SuspendResume { 900 public: 901 enum State { 902 SR_RUNNING, 903 SR_SUSPEND_REQUEST, 904 SR_SUSPENDED, 905 SR_WAKEUP_REQUEST 906 }; 907 908 private: 909 volatile State _state; 910 911 private: 912 /* try to switch state from state "from" to state "to" 913 * returns the state set after the method is complete 914 */ 915 State switch_state(State from, State to); 916 917 public: 918 SuspendResume() : _state(SR_RUNNING) { } 919 920 State state() const { return _state; } 921 922 State request_suspend() { 923 return switch_state(SR_RUNNING, SR_SUSPEND_REQUEST); 924 } 925 926 State cancel_suspend() { 927 return switch_state(SR_SUSPEND_REQUEST, SR_RUNNING); 928 } 929 930 State suspended() { 931 return switch_state(SR_SUSPEND_REQUEST, SR_SUSPENDED); 932 } 933 934 State request_wakeup() { 935 return switch_state(SR_SUSPENDED, SR_WAKEUP_REQUEST); 936 } 937 938 State running() { 939 return switch_state(SR_WAKEUP_REQUEST, SR_RUNNING); 940 } 941 942 bool is_running() const { 943 return _state == SR_RUNNING; 944 } 945 946 bool is_suspend_request() const { 947 return _state == SR_SUSPEND_REQUEST; 948 } 949 950 bool is_suspended() const { 951 return _state == SR_SUSPENDED; 952 } 953 }; 954 #endif // !WINDOWS 955 956 957 protected: 958 static long _rand_seed; // seed for random number generator 959 static int _processor_count; // number of processors 960 static int _initial_active_processor_count; // number of active processors during initialization. 961 962 static char* format_boot_path(const char* format_string, 963 const char* home, 964 int home_len, 965 char fileSep, 966 char pathSep); 967 static bool set_boot_path(char fileSep, char pathSep); 968 969 }; 970 971 // Note that "PAUSE" is almost always used with synchronization 972 // so arguably we should provide Atomic::SpinPause() instead 973 // of the global SpinPause() with C linkage. 974 // It'd also be eligible for inlining on many platforms. 975 976 extern "C" int SpinPause(); 977 978 #endif // SHARE_VM_RUNTIME_OS_HPP