1 /*
2 * Copyright (c) 1997, 2011, 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
43 // os defines the interface to operating system; this includes traditional
44 // OS services (time, I/O) as well as other functionality with system-
45 // dependent code.
46
47 typedef void (*dll_func)(...);
48
49 class Thread;
50 class JavaThread;
51 class Event;
52 class DLL;
53 class FileHandle;
54 template<class E> class GrowableArray;
55
56 // %%%%% Moved ThreadState, START_FN, OSThread to new osThread.hpp. -- Rose
57
58 // Platform-independent error return values from OS functions
59 enum OSReturn {
60 OS_OK = 0, // Operation was successful
61 OS_ERR = -1, // Operation failed
62 OS_INTRPT = -2, // Operation was interrupted
63 OS_TIMEOUT = -3, // Operation timed out
64 OS_NOMEM = -5, // Operation failed for lack of memory
65 OS_NORESOURCE = -6 // Operation failed for lack of nonmemory resource
66 };
67
68 enum ThreadPriority { // JLS 20.20.1-3
69 NoPriority = -1, // Initial non-priority value
70 MinPriority = 1, // Minimum priority
71 NormPriority = 5, // Normal (non-daemon) priority
72 NearMaxPriority = 9, // High priority, used for VMThread
73 MaxPriority = 10 // Highest priority, used for WatcherThread
74 // ensures that VMThread doesn't starve profiler
75 };
76
77 // Typedef for structured exception handling support
78 typedef void (*java_call_t)(JavaValue* value, methodHandle* method, JavaCallArguments* args, Thread* thread);
79
80 class os: AllStatic {
81 public:
82 enum { page_sizes_max = 9 }; // Size of _page_sizes array (8 plus a sentinel)
83
84 private:
85 static OSThread* _starting_thread;
86 static address _polling_page;
87 static volatile int32_t * _mem_serialize_page;
88 static uintptr_t _serialize_page_mask;
89 public:
90 static size_t _page_sizes[page_sizes_max];
91
92 private:
93 static void init_page_sizes(size_t default_page_size) {
94 _page_sizes[0] = default_page_size;
95 _page_sizes[1] = 0; // sentinel
96 }
97
98 public:
99
100 static void init(void); // Called before command line parsing
101 static jint init_2(void); // Called after command line parsing
102 static void init_3(void); // Called at the end of vm init
103
104 // File names are case-insensitive on windows only
105 // Override me as needed
106 static int file_name_strcmp(const char* s1, const char* s2);
107
108 static bool getenv(const char* name, char* buffer, int len);
109 static bool have_special_privileges();
110
111 static jlong javaTimeMillis();
112 static jlong javaTimeNanos();
113 static void javaTimeNanos_info(jvmtiTimerInfo *info_ptr);
114 static void run_periodic_checks();
115
116
117 // Returns the elapsed time in seconds since the vm started.
118 static double elapsedTime();
119
120 // Returns real time in seconds since an arbitrary point
121 // in the past.
122 static bool getTimesSecs(double* process_real_time,
123 double* process_user_time,
124 double* process_system_time);
125
126 // Interface to the performance counter
127 static jlong elapsed_counter();
128 static jlong elapsed_frequency();
129
130 // The "virtual time" of a thread is the amount of time a thread has
131 // actually run. The first function indicates whether the OS supports
132 // this functionality for the current thread, and if so:
133 // * the second enables vtime tracking (if that is required).
134 // * the third tells whether vtime is enabled.
135 // * the fourth returns the elapsed virtual time for the current
136 // thread.
137 static bool supports_vtime();
138 static bool enable_vtime();
139 static bool vtime_enabled();
140 static double elapsedVTime();
141
142 // Return current local time in a string (YYYY-MM-DD HH:MM:SS).
143 // It is MT safe, but not async-safe, as reading time zone
144 // information may require a lock on some platforms.
145 static char* local_time_string(char *buf, size_t buflen);
146 static struct tm* localtime_pd (const time_t* clock, struct tm* res);
147 // Fill in buffer with current local time as an ISO-8601 string.
148 // E.g., YYYY-MM-DDThh:mm:ss.mmm+zzzz.
149 // Returns buffer, or NULL if it failed.
150 static char* iso8601_time(char* buffer, size_t buffer_length);
151
152 // Interface for detecting multiprocessor system
153 static inline bool is_MP() {
154 assert(_processor_count > 0, "invalid processor count");
155 return _processor_count > 1;
156 }
157 static julong available_memory();
158 static julong physical_memory();
159 static julong allocatable_physical_memory(julong size);
160 static bool is_server_class_machine();
161
162 // number of CPUs
163 static int processor_count() {
164 return _processor_count;
165 }
166 static void set_processor_count(int count) { _processor_count = count; }
167
168 // Returns the number of CPUs this process is currently allowed to run on.
169 // Note that on some OSes this can change dynamically.
170 static int active_processor_count();
171
172 // Bind processes to processors.
173 // This is a two step procedure:
174 // first you generate a distribution of processes to processors,
175 // then you bind processes according to that distribution.
176 // Compute a distribution for number of processes to processors.
177 // Stores the processor id's into the distribution array argument.
178 // Returns true if it worked, false if it didn't.
179 static bool distribute_processes(uint length, uint* distribution);
180 // Binds the current process to a processor.
181 // Returns true if it worked, false if it didn't.
182 static bool bind_to_processor(uint processor_id);
183
184 // Interface for stack banging (predetect possible stack overflow for
185 // exception processing) There are guard pages, and above that shadow
186 // pages for stack overflow checking.
187 static bool uses_stack_guard_pages();
188 static bool allocate_stack_guard_pages();
189 static void bang_stack_shadow_pages();
190 static bool stack_shadow_pages_available(Thread *thread, methodHandle method);
191
192 // OS interface to Virtual Memory
193
194 // Return the default page size.
195 static int vm_page_size();
196
197 // Return the page size to use for a region of memory. The min_pages argument
198 // is a hint intended to limit fragmentation; it says the returned page size
199 // should be <= region_max_size / min_pages. Because min_pages is a hint,
200 // this routine may return a size larger than region_max_size / min_pages.
201 //
202 // The current implementation ignores min_pages if a larger page size is an
203 // exact multiple of both region_min_size and region_max_size. This allows
204 // larger pages to be used when doing so would not cause fragmentation; in
205 // particular, a single page can be used when region_min_size ==
206 // region_max_size == a supported page size.
207 static size_t page_size_for_region(size_t region_min_size,
208 size_t region_max_size,
209 uint min_pages);
210
211 // Method for tracing page sizes returned by the above method; enabled by
212 // TracePageSizes. The region_{min,max}_size parameters should be the values
213 // passed to page_size_for_region() and page_size should be the result of that
214 // call. The (optional) base and size parameters should come from the
215 // ReservedSpace base() and size() methods.
216 static void trace_page_sizes(const char* str, const size_t region_min_size,
217 const size_t region_max_size,
218 const size_t page_size,
219 const char* base = NULL,
220 const size_t size = 0) PRODUCT_RETURN;
221
222 static int vm_allocation_granularity();
223 static char* reserve_memory(size_t bytes, char* addr = 0,
224 size_t alignment_hint = 0);
225 static char* attempt_reserve_memory_at(size_t bytes, char* addr);
226 static void split_reserved_memory(char *base, size_t size,
227 size_t split, bool realloc);
228 static bool commit_memory(char* addr, size_t bytes,
229 bool executable = false);
230 static bool commit_memory(char* addr, size_t size, size_t alignment_hint,
231 bool executable = false);
232 static bool uncommit_memory(char* addr, size_t bytes);
233 static bool release_memory(char* addr, size_t bytes);
234
235 enum ProtType { MEM_PROT_NONE, MEM_PROT_READ, MEM_PROT_RW, MEM_PROT_RWX };
236 static bool protect_memory(char* addr, size_t bytes, ProtType prot,
237 bool is_committed = true);
238
239 static bool guard_memory(char* addr, size_t bytes);
240 static bool unguard_memory(char* addr, size_t bytes);
241 static bool create_stack_guard_pages(char* addr, size_t bytes);
242 static bool remove_stack_guard_pages(char* addr, size_t bytes);
243
244 static char* map_memory(int fd, const char* file_name, size_t file_offset,
245 char *addr, size_t bytes, bool read_only = false,
246 bool allow_exec = false);
247 static char* remap_memory(int fd, const char* file_name, size_t file_offset,
248 char *addr, size_t bytes, bool read_only,
249 bool allow_exec);
250 static bool unmap_memory(char *addr, size_t bytes);
251 static void free_memory(char *addr, size_t bytes);
252 static void realign_memory(char *addr, size_t bytes, size_t alignment_hint);
253
254 // NUMA-specific interface
255 static bool numa_has_static_binding();
256 static bool numa_has_group_homing();
257 static void numa_make_local(char *addr, size_t bytes, int lgrp_hint);
258 static void numa_make_global(char *addr, size_t bytes);
259 static size_t numa_get_groups_num();
260 static size_t numa_get_leaf_groups(int *ids, size_t size);
261 static bool numa_topology_changed();
262 static int numa_get_group_id();
263
264 // Page manipulation
265 struct page_info {
266 size_t size;
267 int lgrp_id;
268 };
269 static bool get_page_info(char *start, page_info* info);
270 static char* scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found);
271
272 static char* non_memory_address_word();
273 // reserve, commit and pin the entire memory region
274 static char* reserve_memory_special(size_t size, char* addr = NULL,
275 bool executable = false);
276 static bool release_memory_special(char* addr, size_t bytes);
277 static bool large_page_init();
278 static size_t large_page_size();
279 static bool can_commit_large_page_memory();
280 static bool can_execute_large_page_memory();
281
282 // OS interface to polling page
283 static address get_polling_page() { return _polling_page; }
284 static void set_polling_page(address page) { _polling_page = page; }
285 static bool is_poll_address(address addr) { return addr >= _polling_page && addr < (_polling_page + os::vm_page_size()); }
286 static void make_polling_page_unreadable();
287 static void make_polling_page_readable();
288
289 // Routines used to serialize the thread state without using membars
290 static void serialize_thread_states();
291
292 // Since we write to the serialize page from every thread, we
293 // want stores to be on unique cache lines whenever possible
294 // in order to minimize CPU cross talk. We pre-compute the
295 // amount to shift the thread* to make this offset unique to
296 // each thread.
297 static int get_serialize_page_shift_count() {
298 return SerializePageShiftCount;
299 }
300
301 static void set_serialize_page_mask(uintptr_t mask) {
302 _serialize_page_mask = mask;
303 }
304
305 static unsigned int get_serialize_page_mask() {
306 return _serialize_page_mask;
307 }
308
309 static void set_memory_serialize_page(address page);
310
311 static address get_memory_serialize_page() {
312 return (address)_mem_serialize_page;
313 }
314
315 static inline void write_memory_serialize_page(JavaThread *thread) {
316 uintptr_t page_offset = ((uintptr_t)thread >>
317 get_serialize_page_shift_count()) &
318 get_serialize_page_mask();
319 *(volatile int32_t *)((uintptr_t)_mem_serialize_page+page_offset) = 1;
320 }
321
322 static bool is_memory_serialize_page(JavaThread *thread, address addr) {
323 if (UseMembar) return false;
324 // Previously this function calculated the exact address of this
325 // thread's serialize page, and checked if the faulting address
326 // was equal. However, some platforms mask off faulting addresses
327 // to the page size, so now we just check that the address is
328 // within the page. This makes the thread argument unnecessary,
329 // but we retain the NULL check to preserve existing behaviour.
330 if (thread == NULL) return false;
331 address page = (address) _mem_serialize_page;
332 return addr >= page && addr < (page + os::vm_page_size());
333 }
334
335 static void block_on_serialize_page_trap();
336
337 // threads
338
339 enum ThreadType {
340 vm_thread,
341 cgc_thread, // Concurrent GC thread
342 pgc_thread, // Parallel GC thread
343 java_thread,
344 compiler_thread,
345 watcher_thread,
346 os_thread
347 };
348
349 static bool create_thread(Thread* thread,
350 ThreadType thr_type,
351 size_t stack_size = 0);
352 static bool create_main_thread(JavaThread* thread);
353 static bool create_attached_thread(JavaThread* thread);
354 static void pd_start_thread(Thread* thread);
355 static void start_thread(Thread* thread);
356
357 static void initialize_thread();
358 static void free_thread(OSThread* osthread);
359
360 // thread id on Linux/64bit is 64bit, on Windows and Solaris, it's 32bit
361 static intx current_thread_id();
362 static int current_process_id();
363 static int sleep(Thread* thread, jlong ms, bool interruptable);
364 static int naked_sleep();
365 static void infinite_sleep(); // never returns, use with CAUTION
366 static void yield(); // Yields to all threads with same priority
367 enum YieldResult {
368 YIELD_SWITCHED = 1, // caller descheduled, other ready threads exist & ran
369 YIELD_NONEREADY = 0, // No other runnable/ready threads.
370 // platform-specific yield return immediately
371 YIELD_UNKNOWN = -1 // Unknown: platform doesn't support _SWITCHED or _NONEREADY
372 // YIELD_SWITCHED and YIELD_NONREADY imply the platform supports a "strong"
373 // yield that can be used in lieu of blocking.
374 } ;
375 static YieldResult NakedYield () ;
376 static void yield_all(int attempts = 0); // Yields to all other threads including lower priority
377 static void loop_breaker(int attempts); // called from within tight loops to possibly influence time-sharing
378 static OSReturn set_priority(Thread* thread, ThreadPriority priority);
379 static OSReturn get_priority(const Thread* const thread, ThreadPriority& priority);
380
381 static void interrupt(Thread* thread);
382 static bool is_interrupted(Thread* thread, bool clear_interrupted);
383
384 static int pd_self_suspend_thread(Thread* thread);
385
386 static ExtendedPC fetch_frame_from_context(void* ucVoid, intptr_t** sp, intptr_t** fp);
387 static frame fetch_frame_from_context(void* ucVoid);
388
389 static ExtendedPC get_thread_pc(Thread *thread);
390 static void breakpoint();
391
392 static address current_stack_pointer();
393 static address current_stack_base();
394 static size_t current_stack_size();
395
396 static int message_box(const char* title, const char* message);
397 static char* do_you_want_to_debug(const char* message);
398
399 // run cmd in a separate process and return its exit code; or -1 on failures
400 static int fork_and_exec(char *cmd);
401
402 // Set file to send error reports.
403 static void set_error_file(const char *logfile);
404
405 // os::exit() is merged with vm_exit()
406 // static void exit(int num);
407
408 // Terminate the VM, but don't exit the process
409 static void shutdown();
410
411 // Terminate with an error. Default is to generate a core file on platforms
412 // that support such things. This calls shutdown() and then aborts.
413 static void abort(bool dump_core = true);
414
415 // Die immediately, no exit hook, no abort hook, no cleanup.
416 static void die();
417
418 // File i/o operations
419 static const int default_file_open_flags();
420 static int open(const char *path, int oflag, int mode);
421 static int close(int fd);
422 static jlong lseek(int fd, jlong offset, int whence);
423 static char* native_path(char *path);
424 static int ftruncate(int fd, jlong length);
425 static int fsync(int fd);
426 static int available(int fd, jlong *bytes);
427
428 //File i/o operations
429
430 static size_t read(int fd, void *buf, unsigned int nBytes);
431 static size_t restartable_read(int fd, void *buf, unsigned int nBytes);
432 static size_t write(int fd, const void *buf, unsigned int nBytes);
433
434 // Reading directories.
435 static DIR* opendir(const char* dirname);
436 static int readdir_buf_size(const char *path);
437 static struct dirent* readdir(DIR* dirp, dirent* dbuf);
438 static int closedir(DIR* dirp);
439
440 // Dynamic library extension
441 static const char* dll_file_extension();
442
443 static const char* get_temp_directory();
444 static const char* get_current_directory(char *buf, int buflen);
445
446 // Builds a platform-specific full library path given a ld path and lib name
447 static void dll_build_name(char* buffer, size_t size,
448 const char* pathname, const char* fname);
449
450 // Symbol lookup, find nearest function name; basically it implements
451 // dladdr() for all platforms. Name of the nearest function is copied
452 // to buf. Distance from its base address is returned as offset.
453 // If function name is not found, buf[0] is set to '\0' and offset is
454 // set to -1.
455 static bool dll_address_to_function_name(address addr, char* buf,
456 int buflen, int* offset);
457
458 // Locate DLL/DSO. On success, full path of the library is copied to
459 // buf, and offset is set to be the distance between addr and the
460 // library's base address. On failure, buf[0] is set to '\0' and
461 // offset is set to -1.
462 static bool dll_address_to_library_name(address addr, char* buf,
463 int buflen, int* offset);
464
465 // Find out whether the pc is in the static code for jvm.dll/libjvm.so.
466 static bool address_is_in_vm(address addr);
467
468 // Loads .dll/.so and
469 // in case of error it checks if .dll/.so was built for the
470 // same architecture as Hotspot is running on
471 static void* dll_load(const char *name, char *ebuf, int ebuflen);
472
473 // lookup symbol in a shared library
474 static void* dll_lookup(void* handle, const char* name);
475
476 // Unload library
477 static void dll_unload(void *lib);
478
479 // Print out system information; they are called by fatal error handler.
480 // Output format may be different on different platforms.
481 static void print_os_info(outputStream* st);
482 static void print_cpu_info(outputStream* st);
483 static void print_memory_info(outputStream* st);
484 static void print_dll_info(outputStream* st);
485 static void print_environment_variables(outputStream* st, const char** env_list, char* buffer, int len);
486 static void print_context(outputStream* st, void* context);
487 static void print_register_info(outputStream* st, void* context);
488 static void print_siginfo(outputStream* st, void* siginfo);
489 static void print_signal_handlers(outputStream* st, char* buf, size_t buflen);
490 static void print_date_and_time(outputStream* st);
491
492 static void print_location(outputStream* st, intptr_t x, bool verbose = false);
493 static size_t lasterror(char *buf, size_t len);
494
495 // Determines whether the calling process is being debugged by a user-mode debugger.
496 static bool is_debugger_attached();
497
498 // check if a debugger is attached and if so, wait for a key press
499 static void os::check_for_debugger_and_wait(void);
500
501 // The following two functions are used by fatal error handler to trace
502 // native (C) frames. They are not part of frame.hpp/frame.cpp because
503 // frame.hpp/cpp assume thread is JavaThread, and also because different
504 // OS/compiler may have different convention or provide different API to
505 // walk C frames.
506 //
507 // We don't attempt to become a debugger, so we only follow frames if that
508 // does not require a lookup in the unwind table, which is part of the binary
509 // file but may be unsafe to read after a fatal error. So on x86, we can
510 // only walk stack if %ebp is used as frame pointer; on ia64, it's not
511 // possible to walk C stack without having the unwind table.
512 static bool is_first_C_frame(frame *fr);
513 static frame get_sender_for_C_frame(frame *fr);
514
515 // return current frame. pc() and sp() are set to NULL on failure.
516 static frame current_frame();
517
518 static void print_hex_dump(outputStream* st, address start, address end, int unitsize);
519
520 // returns a string to describe the exception/signal;
521 // returns NULL if exception_code is not an OS exception/signal.
522 static const char* exception_name(int exception_code, char* buf, size_t buflen);
523
524 // Returns native Java library, loads if necessary
525 static void* native_java_library();
526
527 // Fills in path to jvm.dll/libjvm.so (used by the Disassembler)
528 static void jvm_path(char *buf, jint buflen);
529
530 // Returns true if we are running in a headless jre.
531 static bool is_headless_jre();
532
533 // JNI names
534 static void print_jni_name_prefix_on(outputStream* st, int args_size);
535 static void print_jni_name_suffix_on(outputStream* st, int args_size);
536
537 // File conventions
538 static const char* file_separator();
539 static const char* line_separator();
540 static const char* path_separator();
541
542 // Init os specific system properties values
543 static void init_system_properties_values();
544
545 // IO operations, non-JVM_ version.
546 static int stat(const char* path, struct stat* sbuf);
547 static bool dir_is_empty(const char* path);
548
549 // IO operations on binary files
550 static int create_binary_file(const char* path, bool rewrite_existing);
551 static jlong current_file_offset(int fd);
552 static jlong seek_to_file_offset(int fd, jlong offset);
553
554 // Thread Local Storage
555 static int allocate_thread_local_storage();
556 static void thread_local_storage_at_put(int index, void* value);
557 static void* thread_local_storage_at(int index);
558 static void free_thread_local_storage(int index);
559
560 // General allocation (must be MT-safe)
561 static void* malloc (size_t size);
562 static void* realloc (void *memblock, size_t size);
563 static void free (void *memblock);
564 static bool check_heap(bool force = false); // verify C heap integrity
565 static char* strdup(const char *); // Like strdup
566
567 #ifndef PRODUCT
568 static int num_mallocs; // # of calls to malloc/realloc
569 static size_t alloc_bytes; // # of bytes allocated
570 static int num_frees; // # of calls to free
571 #endif
572
573 // SocketInterface (ex HPI SocketInterface )
574 static int socket(int domain, int type, int protocol);
575 static int socket_close(int fd);
576 static int socket_shutdown(int fd, int howto);
577 static int recv(int fd, char *buf, int nBytes, int flags);
578 static int send(int fd, char *buf, int nBytes, int flags);
579 static int raw_send(int fd, char *buf, int nBytes, int flags);
580 static int timeout(int fd, long timeout);
581 static int listen(int fd, int count);
582 static int connect(int fd, struct sockaddr *him, int len);
583 static int bind(int fd, struct sockaddr *him, int len);
584 static int accept(int fd, struct sockaddr *him, int *len);
585 static int recvfrom(int fd, char *buf, int nbytes, int flags,
586 struct sockaddr *from, int *fromlen);
587 static int get_sock_name(int fd, struct sockaddr *him, int *len);
588 static int sendto(int fd, char *buf, int len, int flags,
589 struct sockaddr *to, int tolen);
590 static int socket_available(int fd, jint *pbytes);
591
592 static int get_sock_opt(int fd, int level, int optname,
593 char *optval, int* optlen);
594 static int set_sock_opt(int fd, int level, int optname,
595 const char *optval, int optlen);
596 static int get_host_name(char* name, int namelen);
597
598 static struct hostent* get_host_by_name(char* name);
599
600 // Printing 64 bit integers
601 static const char* jlong_format_specifier();
602 static const char* julong_format_specifier();
603
604 // Support for signals (see JVM_RaiseSignal, JVM_RegisterSignal)
605 static void signal_init();
606 static void signal_init_pd();
607 static void signal_notify(int signal_number);
608 static void* signal(int signal_number, void* handler);
609 static void signal_raise(int signal_number);
610 static int signal_wait();
611 static int signal_lookup();
612 static void* user_handler();
613 static void terminate_signal_thread();
614 static int sigexitnum_pd();
615
616 // random number generation
617 static long random(); // return 32bit pseudorandom number
618 static void init_random(long initval); // initialize random sequence
619
620 // Structured OS Exception support
621 static void os_exception_wrapper(java_call_t f, JavaValue* value, methodHandle* method, JavaCallArguments* args, Thread* thread);
622
623 // On Windows this will create an actual minidump, on Linux/Solaris it will simply check core dump limits
624 static void check_or_create_dump(void* exceptionRecord, void* contextRecord, char* buffer, size_t bufferSize);
625
626 // JVMTI & JVM monitoring and management support
627 // The thread_cpu_time() and current_thread_cpu_time() are only
628 // supported if is_thread_cpu_time_supported() returns true.
629 // They are not supported on Solaris T1.
630
631 // Thread CPU Time - return the fast estimate on a platform
632 // On Solaris - call gethrvtime (fast) - user time only
633 // On Linux - fast clock_gettime where available - user+sys
634 // - otherwise: very slow /proc fs - user+sys
635 // On Windows - GetThreadTimes - user+sys
636 static jlong current_thread_cpu_time();
637 static jlong thread_cpu_time(Thread* t);
638
639 // Thread CPU Time with user_sys_cpu_time parameter.
640 //
641 // If user_sys_cpu_time is true, user+sys time is returned.
642 // Otherwise, only user time is returned
643 static jlong current_thread_cpu_time(bool user_sys_cpu_time);
644 static jlong thread_cpu_time(Thread* t, bool user_sys_cpu_time);
645
646 // Return a bunch of info about the timers.
647 // Note that the returned info for these two functions may be different
648 // on some platforms
649 static void current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr);
650 static void thread_cpu_time_info(jvmtiTimerInfo *info_ptr);
651
652 static bool is_thread_cpu_time_supported();
653
654 // System loadavg support. Returns -1 if load average cannot be obtained.
655 static int loadavg(double loadavg[], int nelem);
656
657 // Hook for os specific jvm options that we don't want to abort on seeing
658 static bool obsolete_option(const JavaVMOption *option);
659
660 // Platform dependent stuff
661 #ifdef TARGET_OS_FAMILY_linux
662 # include "os_linux.hpp"
663 #endif
664 #ifdef TARGET_OS_FAMILY_solaris
665 # include "os_solaris.hpp"
666 #endif
667 #ifdef TARGET_OS_FAMILY_windows
668 # include "os_windows.hpp"
669 #endif
670 #ifdef TARGET_OS_ARCH_linux_x86
671 # include "os_linux_x86.hpp"
672 #endif
673 #ifdef TARGET_OS_ARCH_linux_sparc
674 # include "os_linux_sparc.hpp"
675 #endif
676 #ifdef TARGET_OS_ARCH_linux_zero
677 # include "os_linux_zero.hpp"
678 #endif
679 #ifdef TARGET_OS_ARCH_solaris_x86
680 # include "os_solaris_x86.hpp"
681 #endif
682 #ifdef TARGET_OS_ARCH_solaris_sparc
683 # include "os_solaris_sparc.hpp"
684 #endif
685 #ifdef TARGET_OS_ARCH_windows_x86
686 # include "os_windows_x86.hpp"
687 #endif
688 #ifdef TARGET_OS_ARCH_linux_arm
689 # include "os_linux_arm.hpp"
690 #endif
691 #ifdef TARGET_OS_ARCH_linux_ppc
692 # include "os_linux_ppc.hpp"
693 #endif
694
695
696 // debugging support (mostly used by debug.cpp but also fatal error handler)
697 static bool find(address pc, outputStream* st = tty); // OS specific function to make sense out of an address
698
699 static bool dont_yield(); // when true, JVM_Yield() is nop
700 static void print_statistics();
701
702 // Thread priority helpers (implemented in OS-specific part)
703 static OSReturn set_native_priority(Thread* thread, int native_prio);
704 static OSReturn get_native_priority(const Thread* const thread, int* priority_ptr);
705 static int java_to_os_priority[MaxPriority + 1];
706 // Hint to the underlying OS that a task switch would not be good.
707 // Void return because it's a hint and can fail.
708 static void hint_no_preempt();
709
710 // Used at creation if requested by the diagnostic flag PauseAtStartup.
711 // Causes the VM to wait until an external stimulus has been applied
712 // (for Unix, that stimulus is a signal, for Windows, an external
713 // ResumeThread call)
714 static void pause();
715
716 protected:
717 static long _rand_seed; // seed for random number generator
718 static int _processor_count; // number of processors
719
720 static char* format_boot_path(const char* format_string,
721 const char* home,
722 int home_len,
723 char fileSep,
724 char pathSep);
725 static bool set_boot_path(char fileSep, char pathSep);
726 static char** split_path(const char* path, int* n);
727 };
728
729 // Note that "PAUSE" is almost always used with synchronization
730 // so arguably we should provide Atomic::SpinPause() instead
731 // of the global SpinPause() with C linkage.
732 // It'd also be eligible for inlining on many platforms.
733
734 extern "C" int SpinPause () ;
735 extern "C" int SafeFetch32 (int * adr, int errValue) ;
736 extern "C" intptr_t SafeFetchN (intptr_t * adr, intptr_t errValue) ;
737
738 #endif // SHARE_VM_RUNTIME_OS_HPP