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