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 #endif
36 #ifdef TARGET_OS_FAMILY_solaris
37 # include "jvm_solaris.h"
38 #endif
39 #ifdef TARGET_OS_FAMILY_windows
40 # include "jvm_windows.h"
41 #endif
42 #ifdef TARGET_OS_FAMILY_bsd
43 # include "jvm_bsd.h"
44 #endif
45
46 // os defines the interface to operating system; this includes traditional
47 // OS services (time, I/O) as well as other functionality with system-
48 // dependent code.
49
50 typedef void (*dll_func)(...);
51
52 class Thread;
53 class JavaThread;
54 class Event;
55 class DLL;
56 class FileHandle;
57 template<class E> class GrowableArray;
58
59 // %%%%% Moved ThreadState, START_FN, OSThread to new osThread.hpp. -- Rose
60
61 // Platform-independent error return values from OS functions
62 enum OSReturn {
63 OS_OK = 0, // Operation was successful
64 OS_ERR = -1, // Operation failed
65 OS_INTRPT = -2, // Operation was interrupted
66 OS_TIMEOUT = -3, // Operation timed out
67 OS_NOMEM = -5, // Operation failed for lack of memory
68 OS_NORESOURCE = -6 // Operation failed for lack of nonmemory resource
69 };
70
71 enum ThreadPriority { // JLS 20.20.1-3
72 NoPriority = -1, // Initial non-priority value
73 MinPriority = 1, // Minimum priority
74 NormPriority = 5, // Normal (non-daemon) priority
75 NearMaxPriority = 9, // High priority, used for VMThread
76 MaxPriority = 10, // Highest priority, used for WatcherThread
77 // ensures that VMThread doesn't starve profiler
78 CriticalPriority = 11 // Critical thread priority
79 };
80
81 // Typedef for structured exception handling support
82 typedef void (*java_call_t)(JavaValue* value, methodHandle* method, JavaCallArguments* args, Thread* thread);
83
84 class os: AllStatic {
85 public:
86 enum { page_sizes_max = 9 }; // Size of _page_sizes array (8 plus a sentinel)
87
88 private:
89 static OSThread* _starting_thread;
90 static address _polling_page;
91 static volatile int32_t * _mem_serialize_page;
92 static uintptr_t _serialize_page_mask;
93 public:
94 static size_t _page_sizes[page_sizes_max];
95
96 private:
97 static void init_page_sizes(size_t default_page_size) {
98 _page_sizes[0] = default_page_size;
99 _page_sizes[1] = 0; // sentinel
100 }
101
102 static char* pd_reserve_memory(size_t bytes, char* addr = 0,
103 size_t alignment_hint = 0);
104 static char* pd_attempt_reserve_memory_at(size_t bytes, char* addr);
105 static void pd_split_reserved_memory(char *base, size_t size,
106 size_t split, bool realloc);
107 static bool pd_commit_memory(char* addr, size_t bytes, bool executable = false);
108 static bool pd_commit_memory(char* addr, size_t size, size_t alignment_hint,
109 bool executable = false);
110 static bool pd_uncommit_memory(char* addr, size_t bytes);
111 static bool pd_release_memory(char* addr, size_t bytes);
112
113 static char* pd_map_memory(int fd, const char* file_name, size_t file_offset,
114 char *addr, size_t bytes, bool read_only = false,
115 bool allow_exec = false);
116 static char* pd_remap_memory(int fd, const char* file_name, size_t file_offset,
117 char *addr, size_t bytes, bool read_only,
118 bool allow_exec);
119 static bool pd_unmap_memory(char *addr, size_t bytes);
120 static void pd_free_memory(char *addr, size_t bytes, size_t alignment_hint);
121 static void pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint);
122
123
124 public:
125 static void init(void); // Called before command line parsing
126 static jint init_2(void); // Called after command line parsing
127 static void init_globals(void) { // Called from init_globals() in init.cpp
128 init_globals_ext();
129 }
130 static void init_3(void); // Called at the end of vm init
131
132 // File names are case-insensitive on windows only
133 // Override me as needed
134 static int file_name_strcmp(const char* s1, const char* s2);
135
136 static bool getenv(const char* name, char* buffer, int len);
137 static bool have_special_privileges();
138
139 static jlong javaTimeMillis();
140 static jlong javaTimeNanos();
141 static void javaTimeNanos_info(jvmtiTimerInfo *info_ptr);
142 static void run_periodic_checks();
143
144
145 // Returns the elapsed time in seconds since the vm started.
146 static double elapsedTime();
147
148 // Returns real time in seconds since an arbitrary point
149 // in the past.
150 static bool getTimesSecs(double* process_real_time,
151 double* process_user_time,
152 double* process_system_time);
153
154 // Interface to the performance counter
155 static jlong elapsed_counter();
156 static jlong elapsed_frequency();
157
158 // The "virtual time" of a thread is the amount of time a thread has
159 // actually run. The first function indicates whether the OS supports
160 // this functionality for the current thread, and if so:
161 // * the second enables vtime tracking (if that is required).
162 // * the third tells whether vtime is enabled.
163 // * the fourth returns the elapsed virtual time for the current
164 // thread.
165 static bool supports_vtime();
166 static bool enable_vtime();
167 static bool vtime_enabled();
168 static double elapsedVTime();
169
170 // Return current local time in a string (YYYY-MM-DD HH:MM:SS).
171 // It is MT safe, but not async-safe, as reading time zone
172 // information may require a lock on some platforms.
173 static char* local_time_string(char *buf, size_t buflen);
174 static struct tm* localtime_pd (const time_t* clock, struct tm* res);
175 // Fill in buffer with current local time as an ISO-8601 string.
176 // E.g., YYYY-MM-DDThh:mm:ss.mmm+zzzz.
177 // Returns buffer, or NULL if it failed.
178 static char* iso8601_time(char* buffer, size_t buffer_length);
179
180 // Interface for detecting multiprocessor system
181 static inline bool is_MP() {
182 assert(_processor_count > 0, "invalid processor count");
183 return _processor_count > 1 || AssumeMP;
184 }
185 static julong available_memory();
186 static julong physical_memory();
187 static bool has_allocatable_memory_limit(julong* limit);
188 static bool is_server_class_machine();
189
190 // number of CPUs
191 static int processor_count() {
192 return _processor_count;
193 }
194 static void set_processor_count(int count) { _processor_count = count; }
195
196 // Returns the number of CPUs this process is currently allowed to run on.
197 // Note that on some OSes this can change dynamically.
198 static int active_processor_count();
199
200 // Bind processes to processors.
201 // This is a two step procedure:
202 // first you generate a distribution of processes to processors,
203 // then you bind processes according to that distribution.
204 // Compute a distribution for number of processes to processors.
205 // Stores the processor id's into the distribution array argument.
206 // Returns true if it worked, false if it didn't.
207 static bool distribute_processes(uint length, uint* distribution);
208 // Binds the current process to a processor.
209 // Returns true if it worked, false if it didn't.
210 static bool bind_to_processor(uint processor_id);
211
212 // Give a name to the current thread.
213 static void set_native_thread_name(const char *name);
214
215 // Interface for stack banging (predetect possible stack overflow for
216 // exception processing) There are guard pages, and above that shadow
217 // pages for stack overflow checking.
218 static bool uses_stack_guard_pages();
219 static bool allocate_stack_guard_pages();
220 static void bang_stack_shadow_pages();
221 static bool stack_shadow_pages_available(Thread *thread, methodHandle method);
222
223 // OS interface to Virtual Memory
224
225 // Return the default page size.
226 static int vm_page_size();
227
228 // Return the page size to use for a region of memory. The min_pages argument
229 // is a hint intended to limit fragmentation; it says the returned page size
230 // should be <= region_max_size / min_pages. Because min_pages is a hint,
231 // this routine may return a size larger than region_max_size / min_pages.
232 //
233 // The current implementation ignores min_pages if a larger page size is an
234 // exact multiple of both region_min_size and region_max_size. This allows
235 // larger pages to be used when doing so would not cause fragmentation; in
236 // particular, a single page can be used when region_min_size ==
237 // region_max_size == a supported page size.
238 static size_t page_size_for_region(size_t region_min_size,
239 size_t region_max_size,
240 uint min_pages);
241 // return the largest page size used
242 static size_t max_page_size() {
243 // the _page_sizes array is sorted in descending order.
244 return _page_sizes[0];
245 }
246
247 // Methods for tracing page sizes returned by the above method; enabled by
248 // TracePageSizes. The region_{min,max}_size parameters should be the values
249 // passed to page_size_for_region() and page_size should be the result of that
250 // call. The (optional) base and size parameters should come from the
251 // ReservedSpace base() and size() methods.
252 static void trace_page_sizes(const char* str, const size_t* page_sizes,
253 int count) PRODUCT_RETURN;
254 static void trace_page_sizes(const char* str, const size_t region_min_size,
255 const size_t region_max_size,
256 const size_t page_size,
257 const char* base = NULL,
258 const size_t size = 0) PRODUCT_RETURN;
259
260 static int vm_allocation_granularity();
261 static char* reserve_memory(size_t bytes, char* addr = 0,
262 size_t alignment_hint = 0);
263 static char* reserve_memory(size_t bytes, char* addr,
264 size_t alignment_hint, MEMFLAGS flags);
265 static char* reserve_memory_aligned(size_t size, size_t alignment);
266 static char* attempt_reserve_memory_at(size_t bytes, char* addr);
267 static void split_reserved_memory(char *base, size_t size,
268 size_t split, bool realloc);
269 static bool commit_memory(char* addr, size_t bytes, bool executable = false);
270 static bool commit_memory(char* addr, size_t size, size_t alignment_hint,
271 bool executable = false);
272 static bool uncommit_memory(char* addr, size_t bytes);
273 static bool release_memory(char* addr, size_t bytes);
274
275 enum ProtType { MEM_PROT_NONE, MEM_PROT_READ, MEM_PROT_RW, MEM_PROT_RWX };
276 static bool protect_memory(char* addr, size_t bytes, ProtType prot,
277 bool is_committed = true);
278
279 static bool guard_memory(char* addr, size_t bytes);
280 static bool unguard_memory(char* addr, size_t bytes);
281 static bool create_stack_guard_pages(char* addr, size_t bytes);
282 static bool pd_create_stack_guard_pages(char* addr, size_t bytes);
283 static bool remove_stack_guard_pages(char* addr, size_t bytes);
284
285 static char* map_memory(int fd, const char* file_name, size_t file_offset,
286 char *addr, size_t bytes, bool read_only = false,
287 bool allow_exec = false);
288 static char* remap_memory(int fd, const char* file_name, size_t file_offset,
289 char *addr, size_t bytes, bool read_only,
290 bool allow_exec);
291 static bool unmap_memory(char *addr, size_t bytes);
292 static void free_memory(char *addr, size_t bytes, size_t alignment_hint);
293 static void realign_memory(char *addr, size_t bytes, size_t alignment_hint);
294
295 // NUMA-specific interface
296 static bool numa_has_static_binding();
297 static bool numa_has_group_homing();
298 static void numa_make_local(char *addr, size_t bytes, int lgrp_hint);
299 static void numa_make_global(char *addr, size_t bytes);
300 static size_t numa_get_groups_num();
301 static size_t numa_get_leaf_groups(int *ids, size_t size);
302 static bool numa_topology_changed();
303 static int numa_get_group_id();
304
305 // Page manipulation
306 struct page_info {
307 size_t size;
308 int lgrp_id;
309 };
310 static bool get_page_info(char *start, page_info* info);
311 static char* scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found);
312
313 static char* non_memory_address_word();
314 // reserve, commit and pin the entire memory region
315 static char* reserve_memory_special(size_t size, char* addr = NULL,
316 bool executable = false);
317 static bool release_memory_special(char* addr, size_t bytes);
318 static void large_page_init();
319 static size_t large_page_size();
320 static bool can_commit_large_page_memory();
321 static bool can_execute_large_page_memory();
322
323 // OS interface to polling page
324 static address get_polling_page() { return _polling_page; }
325 static void set_polling_page(address page) { _polling_page = page; }
326 static bool is_poll_address(address addr) { return addr >= _polling_page && addr < (_polling_page + os::vm_page_size()); }
327 static void make_polling_page_unreadable();
328 static void make_polling_page_readable();
329
330 // Routines used to serialize the thread state without using membars
331 static void serialize_thread_states();
332
333 // Since we write to the serialize page from every thread, we
334 // want stores to be on unique cache lines whenever possible
335 // in order to minimize CPU cross talk. We pre-compute the
336 // amount to shift the thread* to make this offset unique to
337 // each thread.
338 static int get_serialize_page_shift_count() {
339 return SerializePageShiftCount;
340 }
341
342 static void set_serialize_page_mask(uintptr_t mask) {
343 _serialize_page_mask = mask;
344 }
345
346 static unsigned int get_serialize_page_mask() {
347 return _serialize_page_mask;
348 }
349
350 static void set_memory_serialize_page(address page);
351
352 static address get_memory_serialize_page() {
353 return (address)_mem_serialize_page;
354 }
355
356 static inline void write_memory_serialize_page(JavaThread *thread) {
357 uintptr_t page_offset = ((uintptr_t)thread >>
358 get_serialize_page_shift_count()) &
359 get_serialize_page_mask();
360 *(volatile int32_t *)((uintptr_t)_mem_serialize_page+page_offset) = 1;
361 }
362
363 static bool is_memory_serialize_page(JavaThread *thread, address addr) {
364 if (UseMembar) return false;
365 // Previously this function calculated the exact address of this
366 // thread's serialize page, and checked if the faulting address
367 // was equal. However, some platforms mask off faulting addresses
368 // to the page size, so now we just check that the address is
369 // within the page. This makes the thread argument unnecessary,
370 // but we retain the NULL check to preserve existing behaviour.
371 if (thread == NULL) return false;
372 address page = (address) _mem_serialize_page;
373 return addr >= page && addr < (page + os::vm_page_size());
374 }
375
376 static void block_on_serialize_page_trap();
377
378 // threads
379
380 enum ThreadType {
381 vm_thread,
382 cgc_thread, // Concurrent GC thread
383 pgc_thread, // Parallel GC thread
384 java_thread,
385 compiler_thread,
386 watcher_thread,
387 os_thread
388 };
389
390 static bool create_thread(Thread* thread,
391 ThreadType thr_type,
392 size_t stack_size = 0);
393 static bool create_main_thread(JavaThread* thread);
394 static bool create_attached_thread(JavaThread* thread);
395 static void pd_start_thread(Thread* thread);
396 static void start_thread(Thread* thread);
397
398 static void initialize_thread(Thread* thr);
399 static void free_thread(OSThread* osthread);
400
401 // thread id on Linux/64bit is 64bit, on Windows and Solaris, it's 32bit
402 static intx current_thread_id();
403 static int current_process_id();
404 static int sleep(Thread* thread, jlong ms, bool interruptable);
405 static int naked_sleep();
406 static void infinite_sleep(); // never returns, use with CAUTION
407 static void yield(); // Yields to all threads with same priority
408 enum YieldResult {
409 YIELD_SWITCHED = 1, // caller descheduled, other ready threads exist & ran
410 YIELD_NONEREADY = 0, // No other runnable/ready threads.
411 // platform-specific yield return immediately
412 YIELD_UNKNOWN = -1 // Unknown: platform doesn't support _SWITCHED or _NONEREADY
413 // YIELD_SWITCHED and YIELD_NONREADY imply the platform supports a "strong"
414 // yield that can be used in lieu of blocking.
415 } ;
416 static YieldResult NakedYield () ;
417 static void yield_all(int attempts = 0); // Yields to all other threads including lower priority
418 static void loop_breaker(int attempts); // called from within tight loops to possibly influence time-sharing
419 static OSReturn set_priority(Thread* thread, ThreadPriority priority);
420 static OSReturn get_priority(const Thread* const thread, ThreadPriority& priority);
421
422 static void interrupt(Thread* thread);
423 static bool is_interrupted(Thread* thread, bool clear_interrupted);
424
425 static int pd_self_suspend_thread(Thread* thread);
426
427 static ExtendedPC fetch_frame_from_context(void* ucVoid, intptr_t** sp, intptr_t** fp);
428 static frame fetch_frame_from_context(void* ucVoid);
429
430 static ExtendedPC get_thread_pc(Thread *thread);
431 static void breakpoint();
432
433 static address current_stack_pointer();
434 static address current_stack_base();
435 static size_t current_stack_size();
436
437 static void verify_stack_alignment() PRODUCT_RETURN;
438
439 static int message_box(const char* title, const char* message);
440 static char* do_you_want_to_debug(const char* message);
441
442 // run cmd in a separate process and return its exit code; or -1 on failures
443 static int fork_and_exec(char *cmd);
444
445 // Set file to send error reports.
446 static void set_error_file(const char *logfile);
447
448 // os::exit() is merged with vm_exit()
449 // static void exit(int num);
450
451 // Terminate the VM, but don't exit the process
452 static void shutdown();
453
454 // Terminate with an error. Default is to generate a core file on platforms
455 // that support such things. This calls shutdown() and then aborts.
456 static void abort(bool dump_core = true);
457
458 // Die immediately, no exit hook, no abort hook, no cleanup.
459 static void die();
460
461 // File i/o operations
462 static const int default_file_open_flags();
463 static int open(const char *path, int oflag, int mode);
464 static FILE* open(int fd, const char* mode);
465 static int close(int fd);
466 static jlong lseek(int fd, jlong offset, int whence);
467 static char* native_path(char *path);
468 static int ftruncate(int fd, jlong length);
469 static int fsync(int fd);
470 static int available(int fd, jlong *bytes);
471
472 //File i/o operations
473
474 static size_t read(int fd, void *buf, unsigned int nBytes);
475 static size_t restartable_read(int fd, void *buf, unsigned int nBytes);
476 static size_t write(int fd, const void *buf, unsigned int nBytes);
477
478 // Reading directories.
479 static DIR* opendir(const char* dirname);
480 static int readdir_buf_size(const char *path);
481 static struct dirent* readdir(DIR* dirp, dirent* dbuf);
482 static int closedir(DIR* dirp);
483
484 // Dynamic library extension
485 static const char* dll_file_extension();
486
487 static const char* get_temp_directory();
488 static const char* get_current_directory(char *buf, size_t buflen);
489
490 // Builds a platform-specific full library path given a ld path and lib name
491 // Returns true if buffer contains full path to existing file, false otherwise
492 static bool dll_build_name(char* buffer, size_t size,
493 const char* pathname, const char* fname);
494
495 // Symbol lookup, find nearest function name; basically it implements
496 // dladdr() for all platforms. Name of the nearest function is copied
497 // to buf. Distance from its base address is returned as offset.
498 // If function name is not found, buf[0] is set to '\0' and offset is
499 // set to -1.
500 static bool dll_address_to_function_name(address addr, char* buf,
501 int buflen, int* offset);
502
503 // Locate DLL/DSO. On success, full path of the library is copied to
504 // buf, and offset is set to be the distance between addr and the
505 // library's base address. On failure, buf[0] is set to '\0' and
506 // offset is set to -1.
507 static bool dll_address_to_library_name(address addr, char* buf,
508 int buflen, int* offset);
509
510 // Find out whether the pc is in the static code for jvm.dll/libjvm.so.
511 static bool address_is_in_vm(address addr);
512
513 // Loads .dll/.so and
514 // in case of error it checks if .dll/.so was built for the
515 // same architecture as Hotspot is running on
516 static void* dll_load(const char *name, char *ebuf, int ebuflen);
517
518 // lookup symbol in a shared library
519 static void* dll_lookup(void* handle, const char* name);
520
521 // Unload library
522 static void dll_unload(void *lib);
523
524 // Print out system information; they are called by fatal error handler.
525 // Output format may be different on different platforms.
526 static void print_os_info(outputStream* st);
527 static void print_os_info_brief(outputStream* st);
528 static void print_cpu_info(outputStream* st);
529 static void pd_print_cpu_info(outputStream* st);
530 static void print_memory_info(outputStream* st);
531 static void print_dll_info(outputStream* st);
532 static void print_environment_variables(outputStream* st, const char** env_list, char* buffer, int len);
533 static void print_context(outputStream* st, void* context);
534 static void print_register_info(outputStream* st, void* context);
535 static void print_siginfo(outputStream* st, void* siginfo);
536 static void print_signal_handlers(outputStream* st, char* buf, size_t buflen);
537 static void print_date_and_time(outputStream* st);
538
539 static void print_location(outputStream* st, intptr_t x, bool verbose = false);
540 static size_t lasterror(char *buf, size_t len);
541 static int get_last_error();
542
543 // Determines whether the calling process is being debugged by a user-mode debugger.
544 static bool is_debugger_attached();
545
546 // wait for a key press if PauseAtExit is set
547 static void wait_for_keypress_at_exit(void);
548
549 // The following two functions are used by fatal error handler to trace
550 // native (C) frames. They are not part of frame.hpp/frame.cpp because
551 // frame.hpp/cpp assume thread is JavaThread, and also because different
552 // OS/compiler may have different convention or provide different API to
553 // walk C frames.
554 //
555 // We don't attempt to become a debugger, so we only follow frames if that
556 // does not require a lookup in the unwind table, which is part of the binary
557 // file but may be unsafe to read after a fatal error. So on x86, we can
558 // only walk stack if %ebp is used as frame pointer; on ia64, it's not
559 // possible to walk C stack without having the unwind table.
560 static bool is_first_C_frame(frame *fr);
561 static frame get_sender_for_C_frame(frame *fr);
562
563 // return current frame. pc() and sp() are set to NULL on failure.
564 static frame current_frame();
565
566 static void print_hex_dump(outputStream* st, address start, address end, int unitsize);
567
568 // returns a string to describe the exception/signal;
569 // returns NULL if exception_code is not an OS exception/signal.
570 static const char* exception_name(int exception_code, char* buf, size_t buflen);
571
572 // Returns native Java library, loads if necessary
573 static void* native_java_library();
574
575 // Fills in path to jvm.dll/libjvm.so (used by the Disassembler)
576 static void jvm_path(char *buf, jint buflen);
577
578 // Returns true if we are running in a headless jre.
579 static bool is_headless_jre();
580
581 // JNI names
582 static void print_jni_name_prefix_on(outputStream* st, int args_size);
583 static void print_jni_name_suffix_on(outputStream* st, int args_size);
584
585 // File conventions
586 static const char* file_separator();
587 static const char* line_separator();
588 static const char* path_separator();
589
590 // Init os specific system properties values
591 static void init_system_properties_values();
592
593 // IO operations, non-JVM_ version.
594 static int stat(const char* path, struct stat* sbuf);
595 static bool dir_is_empty(const char* path);
596
597 // IO operations on binary files
598 static int create_binary_file(const char* path, bool rewrite_existing);
599 static jlong current_file_offset(int fd);
600 static jlong seek_to_file_offset(int fd, jlong offset);
601
602 // Thread Local Storage
603 static int allocate_thread_local_storage();
604 static void thread_local_storage_at_put(int index, void* value);
605 static void* thread_local_storage_at(int index);
606 static void free_thread_local_storage(int index);
607
608 // Stack walk
609 static address get_caller_pc(int n = 0);
610
611 // General allocation (must be MT-safe)
612 static void* malloc (size_t size, MEMFLAGS flags, address caller_pc = 0);
613 static void* realloc (void *memblock, size_t size, MEMFLAGS flags, address caller_pc = 0);
614 static void free (void *memblock, MEMFLAGS flags = mtNone);
615 static bool check_heap(bool force = false); // verify C heap integrity
616 static char* strdup(const char *, MEMFLAGS flags = mtInternal); // Like strdup
617
618 #ifndef PRODUCT
619 static julong num_mallocs; // # of calls to malloc/realloc
620 static julong alloc_bytes; // # of bytes allocated
621 static julong num_frees; // # of calls to free
622 static julong free_bytes; // # of bytes freed
623 #endif
624
625 // SocketInterface (ex HPI SocketInterface )
626 static int socket(int domain, int type, int protocol);
627 static int socket_close(int fd);
628 static int socket_shutdown(int fd, int howto);
629 static int recv(int fd, char* buf, size_t nBytes, uint flags);
630 static int send(int fd, char* buf, size_t nBytes, uint flags);
631 static int raw_send(int fd, char* buf, size_t nBytes, uint flags);
632 static int timeout(int fd, long timeout);
633 static int listen(int fd, int count);
634 static int connect(int fd, struct sockaddr* him, socklen_t len);
635 static int bind(int fd, struct sockaddr* him, socklen_t len);
636 static int accept(int fd, struct sockaddr* him, socklen_t* len);
637 static int recvfrom(int fd, char* buf, size_t nbytes, uint flags,
638 struct sockaddr* from, socklen_t* fromlen);
639 static int get_sock_name(int fd, struct sockaddr* him, socklen_t* len);
640 static int sendto(int fd, char* buf, size_t len, uint flags,
641 struct sockaddr* to, socklen_t tolen);
642 static int socket_available(int fd, jint* pbytes);
643
644 static int get_sock_opt(int fd, int level, int optname,
645 char* optval, socklen_t* optlen);
646 static int set_sock_opt(int fd, int level, int optname,
647 const char* optval, socklen_t optlen);
648 static int get_host_name(char* name, int namelen);
649
650 static struct hostent* get_host_by_name(char* name);
651
652 // Support for signals (see JVM_RaiseSignal, JVM_RegisterSignal)
653 static void signal_init();
654 static void signal_init_pd();
655 static void signal_notify(int signal_number);
656 static void* signal(int signal_number, void* handler);
657 static void signal_raise(int signal_number);
658 static int signal_wait();
659 static int signal_lookup();
660 static void* user_handler();
661 static void terminate_signal_thread();
662 static int sigexitnum_pd();
663
664 // random number generation
665 static long random(); // return 32bit pseudorandom number
666 static void init_random(long initval); // initialize random sequence
667
668 // Structured OS Exception support
669 static void os_exception_wrapper(java_call_t f, JavaValue* value, methodHandle* method, JavaCallArguments* args, Thread* thread);
670
671 // On Windows this will create an actual minidump, on Linux/Solaris it will simply check core dump limits
672 static void check_or_create_dump(void* exceptionRecord, void* contextRecord, char* buffer, size_t bufferSize);
673
674 // Get the default path to the core file
675 // Returns the length of the string
676 static int get_core_path(char* buffer, size_t bufferSize);
677
678 // JVMTI & JVM monitoring and management support
679 // The thread_cpu_time() and current_thread_cpu_time() are only
680 // supported if is_thread_cpu_time_supported() returns true.
681 // They are not supported on Solaris T1.
682
683 // Thread CPU Time - return the fast estimate on a platform
684 // On Solaris - call gethrvtime (fast) - user time only
685 // On Linux - fast clock_gettime where available - user+sys
686 // - otherwise: very slow /proc fs - user+sys
687 // On Windows - GetThreadTimes - user+sys
688 static jlong current_thread_cpu_time();
689 static jlong thread_cpu_time(Thread* t);
690
691 // Thread CPU Time with user_sys_cpu_time parameter.
692 //
693 // If user_sys_cpu_time is true, user+sys time is returned.
694 // Otherwise, only user time is returned
695 static jlong current_thread_cpu_time(bool user_sys_cpu_time);
696 static jlong thread_cpu_time(Thread* t, bool user_sys_cpu_time);
697
698 // Return a bunch of info about the timers.
699 // Note that the returned info for these two functions may be different
700 // on some platforms
701 static void current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr);
702 static void thread_cpu_time_info(jvmtiTimerInfo *info_ptr);
703
704 static bool is_thread_cpu_time_supported();
705
706 // System loadavg support. Returns -1 if load average cannot be obtained.
707 static int loadavg(double loadavg[], int nelem);
708
709 // Hook for os specific jvm options that we don't want to abort on seeing
710 static bool obsolete_option(const JavaVMOption *option);
711
712 // Read file line by line. If line is longer than bsize,
713 // rest of line is skipped. Returns number of bytes read or -1 on EOF
714 static int get_line_chars(int fd, char *buf, const size_t bsize);
715
716 // Extensions
717 #include "runtime/os_ext.hpp"
718
719 public:
720
721 // Platform dependent stuff
722 #ifdef TARGET_OS_FAMILY_linux
723 # include "os_linux.hpp"
724 # include "os_posix.hpp"
725 #endif
726 #ifdef TARGET_OS_FAMILY_solaris
727 # include "os_solaris.hpp"
728 # include "os_posix.hpp"
729 #endif
730 #ifdef TARGET_OS_FAMILY_windows
731 # include "os_windows.hpp"
732 #endif
733 #ifdef TARGET_OS_FAMILY_bsd
734 # include "os_posix.hpp"
735 # include "os_bsd.hpp"
736 #endif
737 #ifdef TARGET_OS_ARCH_linux_x86
738 # include "os_linux_x86.hpp"
739 #endif
740 #ifdef TARGET_OS_ARCH_linux_sparc
741 # include "os_linux_sparc.hpp"
742 #endif
743 #ifdef TARGET_OS_ARCH_linux_zero
744 # include "os_linux_zero.hpp"
745 #endif
746 #ifdef TARGET_OS_ARCH_solaris_x86
747 # include "os_solaris_x86.hpp"
748 #endif
749 #ifdef TARGET_OS_ARCH_solaris_sparc
750 # include "os_solaris_sparc.hpp"
751 #endif
752 #ifdef TARGET_OS_ARCH_windows_x86
753 # include "os_windows_x86.hpp"
754 #endif
755 #ifdef TARGET_OS_ARCH_linux_arm
756 # include "os_linux_arm.hpp"
757 #endif
758 #ifdef TARGET_OS_ARCH_linux_ppc
759 # include "os_linux_ppc.hpp"
760 #endif
761 #ifdef TARGET_OS_ARCH_bsd_x86
762 # include "os_bsd_x86.hpp"
763 #endif
764 #ifdef TARGET_OS_ARCH_bsd_zero
765 # include "os_bsd_zero.hpp"
766 #endif
767
768 public:
769 // debugging support (mostly used by debug.cpp but also fatal error handler)
770 static bool find(address pc, outputStream* st = tty); // OS specific function to make sense out of an address
771
772 static bool dont_yield(); // when true, JVM_Yield() is nop
773 static void print_statistics();
774
775 // Thread priority helpers (implemented in OS-specific part)
776 static OSReturn set_native_priority(Thread* thread, int native_prio);
777 static OSReturn get_native_priority(const Thread* const thread, int* priority_ptr);
778 static int java_to_os_priority[CriticalPriority + 1];
779 // Hint to the underlying OS that a task switch would not be good.
780 // Void return because it's a hint and can fail.
781 static void hint_no_preempt();
782
783 // Used at creation if requested by the diagnostic flag PauseAtStartup.
784 // Causes the VM to wait until an external stimulus has been applied
785 // (for Unix, that stimulus is a signal, for Windows, an external
786 // ResumeThread call)
787 static void pause();
788
789 protected:
790 static long _rand_seed; // seed for random number generator
791 static int _processor_count; // number of processors
792
793 static char* format_boot_path(const char* format_string,
794 const char* home,
795 int home_len,
796 char fileSep,
797 char pathSep);
798 static bool set_boot_path(char fileSep, char pathSep);
799 static char** split_path(const char* path, int* n);
800 };
801
802 // Note that "PAUSE" is almost always used with synchronization
803 // so arguably we should provide Atomic::SpinPause() instead
804 // of the global SpinPause() with C linkage.
805 // It'd also be eligible for inlining on many platforms.
806
807 extern "C" int SpinPause () ;
808 extern "C" int SafeFetch32 (int * adr, int errValue) ;
809 extern "C" intptr_t SafeFetchN (intptr_t * adr, intptr_t errValue) ;
810
811 #endif // SHARE_VM_RUNTIME_OS_HPP