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 // Executable parameter flag for os::commit_memory() and
82 // os::commit_memory_or_exit().
83 const bool ExecMem = true;
84
85 // Typedef for structured exception handling support
86 typedef void (*java_call_t)(JavaValue* value, methodHandle* method, JavaCallArguments* args, Thread* thread);
87
88 class os: AllStatic {
89 public:
90 enum { page_sizes_max = 9 }; // Size of _page_sizes array (8 plus a sentinel)
91
92 private:
93 static OSThread* _starting_thread;
94 static address _polling_page;
95 static volatile int32_t * _mem_serialize_page;
96 static uintptr_t _serialize_page_mask;
97 public:
98 static size_t _page_sizes[page_sizes_max];
99
100 private:
101 static void init_page_sizes(size_t default_page_size) {
102 _page_sizes[0] = default_page_size;
103 _page_sizes[1] = 0; // sentinel
104 }
105
106 static char* pd_reserve_memory(size_t bytes, char* addr = 0,
107 size_t alignment_hint = 0);
108 static char* pd_attempt_reserve_memory_at(size_t bytes, char* addr);
109 static void pd_split_reserved_memory(char *base, size_t size,
110 size_t split, bool realloc);
111 static bool pd_commit_memory(char* addr, size_t bytes, bool executable);
112 static bool pd_commit_memory(char* addr, size_t size, size_t alignment_hint,
113 bool executable);
114 // Same as pd_commit_memory() that either succeeds or calls
115 // vm_exit_out_of_memory() with the specified mesg.
116 static void pd_commit_memory_or_exit(char* addr, size_t bytes,
117 bool executable, const char* mesg);
118 static void pd_commit_memory_or_exit(char* addr, size_t size,
119 size_t alignment_hint,
120 bool executable, const char* mesg);
121 static bool pd_uncommit_memory(char* addr, size_t bytes);
122 static bool pd_release_memory(char* addr, size_t bytes);
123
124 static char* pd_map_memory(int fd, const char* file_name, size_t file_offset,
125 char *addr, size_t bytes, bool read_only = false,
126 bool allow_exec = false);
127 static char* pd_remap_memory(int fd, const char* file_name, size_t file_offset,
128 char *addr, size_t bytes, bool read_only,
129 bool allow_exec);
130 static bool pd_unmap_memory(char *addr, size_t bytes);
131 static void pd_free_memory(char *addr, size_t bytes, size_t alignment_hint);
132 static void pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint);
133
134
135 public:
136 static void init(void); // Called before command line parsing
137 static jint init_2(void); // Called after command line parsing
138 static void init_globals(void) { // Called from init_globals() in init.cpp
139 init_globals_ext();
140 }
141 static void init_3(void); // Called at the end of vm init
142
143 // File names are case-insensitive on windows only
144 // Override me as needed
145 static int file_name_strcmp(const char* s1, const char* s2);
146
147 static bool getenv(const char* name, char* buffer, int len);
148 static bool have_special_privileges();
149
150 static jlong javaTimeMillis();
151 static jlong javaTimeNanos();
152 static void javaTimeNanos_info(jvmtiTimerInfo *info_ptr);
153 static void run_periodic_checks();
154
155
156 // Returns the elapsed time in seconds since the vm started.
157 static double elapsedTime();
158
159 // Returns real time in seconds since an arbitrary point
160 // in the past.
161 static bool getTimesSecs(double* process_real_time,
162 double* process_user_time,
163 double* process_system_time);
164
165 // Interface to the performance counter
166 static jlong elapsed_counter();
167 static jlong elapsed_frequency();
168
169 // The "virtual time" of a thread is the amount of time a thread has
170 // actually run. The first function indicates whether the OS supports
171 // this functionality for the current thread, and if so:
172 // * the second enables vtime tracking (if that is required).
173 // * the third tells whether vtime is enabled.
174 // * the fourth returns the elapsed virtual time for the current
175 // thread.
176 static bool supports_vtime();
177 static bool enable_vtime();
178 static bool vtime_enabled();
179 static double elapsedVTime();
180
181 // Return current local time in a string (YYYY-MM-DD HH:MM:SS).
182 // It is MT safe, but not async-safe, as reading time zone
183 // information may require a lock on some platforms.
184 static char* local_time_string(char *buf, size_t buflen);
185 static struct tm* localtime_pd (const time_t* clock, struct tm* res);
186 // Fill in buffer with current local time as an ISO-8601 string.
187 // E.g., YYYY-MM-DDThh:mm:ss.mmm+zzzz.
188 // Returns buffer, or NULL if it failed.
189 static char* iso8601_time(char* buffer, size_t buffer_length);
190
191 // Interface for detecting multiprocessor system
192 static inline bool is_MP() {
193 assert(_processor_count > 0, "invalid processor count");
194 return _processor_count > 1 || AssumeMP;
195 }
196 static julong available_memory();
197 static julong physical_memory();
198 static bool has_allocatable_memory_limit(julong* limit);
199 static bool is_server_class_machine();
200
201 // number of CPUs
202 static int processor_count() {
203 return _processor_count;
204 }
205 static void set_processor_count(int count) { _processor_count = count; }
206
207 // Returns the number of CPUs this process is currently allowed to run on.
208 // Note that on some OSes this can change dynamically.
209 static int active_processor_count();
210
211 // Bind processes to processors.
212 // This is a two step procedure:
213 // first you generate a distribution of processes to processors,
214 // then you bind processes according to that distribution.
215 // Compute a distribution for number of processes to processors.
216 // Stores the processor id's into the distribution array argument.
217 // Returns true if it worked, false if it didn't.
218 static bool distribute_processes(uint length, uint* distribution);
219 // Binds the current process to a processor.
220 // Returns true if it worked, false if it didn't.
221 static bool bind_to_processor(uint processor_id);
222
223 // Give a name to the current thread.
224 static void set_native_thread_name(const char *name);
225
226 // Interface for stack banging (predetect possible stack overflow for
227 // exception processing) There are guard pages, and above that shadow
228 // pages for stack overflow checking.
229 static bool uses_stack_guard_pages();
230 static bool allocate_stack_guard_pages();
231 static void bang_stack_shadow_pages();
232 static bool stack_shadow_pages_available(Thread *thread, methodHandle method);
233
234 // OS interface to Virtual Memory
235
236 // Return the default page size.
237 static int vm_page_size();
238
239 // Return the page size to use for a region of memory. The min_pages argument
240 // is a hint intended to limit fragmentation; it says the returned page size
241 // should be <= region_max_size / min_pages. Because min_pages is a hint,
242 // this routine may return a size larger than region_max_size / min_pages.
243 //
244 // The current implementation ignores min_pages if a larger page size is an
245 // exact multiple of both region_min_size and region_max_size. This allows
246 // larger pages to be used when doing so would not cause fragmentation; in
247 // particular, a single page can be used when region_min_size ==
248 // region_max_size == a supported page size.
249 static size_t page_size_for_region(size_t region_min_size,
250 size_t region_max_size,
251 uint min_pages);
252
253 // Methods for tracing page sizes returned by the above method; enabled by
254 // TracePageSizes. The region_{min,max}_size parameters should be the values
255 // passed to page_size_for_region() and page_size should be the result of that
256 // call. The (optional) base and size parameters should come from the
257 // ReservedSpace base() and size() methods.
258 static void trace_page_sizes(const char* str, const size_t* page_sizes,
259 int count) PRODUCT_RETURN;
260 static void trace_page_sizes(const char* str, const size_t region_min_size,
261 const size_t region_max_size,
262 const size_t page_size,
263 const char* base = NULL,
264 const size_t size = 0) PRODUCT_RETURN;
265
266 static int vm_allocation_granularity();
267 static char* reserve_memory(size_t bytes, char* addr = 0,
268 size_t alignment_hint = 0);
269 static char* reserve_memory(size_t bytes, char* addr,
270 size_t alignment_hint, MEMFLAGS flags);
271 static char* reserve_memory_aligned(size_t size, size_t alignment);
272 static char* attempt_reserve_memory_at(size_t bytes, char* addr);
273 static void split_reserved_memory(char *base, size_t size,
274 size_t split, bool realloc);
275 static bool commit_memory(char* addr, size_t bytes, bool executable);
276 static bool commit_memory(char* addr, size_t size, size_t alignment_hint,
277 bool executable);
278 // Same as commit_memory() that either succeeds or calls
279 // vm_exit_out_of_memory() with the specified mesg.
280 static void commit_memory_or_exit(char* addr, size_t bytes,
281 bool executable, const char* mesg);
282 static void commit_memory_or_exit(char* addr, size_t size,
283 size_t alignment_hint,
284 bool executable, const char* mesg);
285 static bool uncommit_memory(char* addr, size_t bytes);
286 static bool release_memory(char* addr, size_t bytes);
287
288 enum ProtType { MEM_PROT_NONE, MEM_PROT_READ, MEM_PROT_RW, MEM_PROT_RWX };
289 static bool protect_memory(char* addr, size_t bytes, ProtType prot,
290 bool is_committed = true);
291
292 static bool guard_memory(char* addr, size_t bytes);
293 static bool unguard_memory(char* addr, size_t bytes);
294 static bool create_stack_guard_pages(char* addr, size_t bytes);
295 static bool pd_create_stack_guard_pages(char* addr, size_t bytes);
296 static bool remove_stack_guard_pages(char* addr, size_t bytes);
297
298 static char* map_memory(int fd, const char* file_name, size_t file_offset,
299 char *addr, size_t bytes, bool read_only = false,
300 bool allow_exec = false);
301 static char* remap_memory(int fd, const char* file_name, size_t file_offset,
302 char *addr, size_t bytes, bool read_only,
303 bool allow_exec);
304 static bool unmap_memory(char *addr, size_t bytes);
305 static void free_memory(char *addr, size_t bytes, size_t alignment_hint);
306 static void realign_memory(char *addr, size_t bytes, size_t alignment_hint);
307
308 // NUMA-specific interface
309 static bool numa_has_static_binding();
310 static bool numa_has_group_homing();
311 static void numa_make_local(char *addr, size_t bytes, int lgrp_hint);
312 static void numa_make_global(char *addr, size_t bytes);
313 static size_t numa_get_groups_num();
314 static size_t numa_get_leaf_groups(int *ids, size_t size);
315 static bool numa_topology_changed();
316 static int numa_get_group_id();
317
318 // Page manipulation
319 struct page_info {
320 size_t size;
321 int lgrp_id;
322 };
323 static bool get_page_info(char *start, page_info* info);
324 static char* scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found);
325
326 static char* non_memory_address_word();
327 // reserve, commit and pin the entire memory region
328 static char* reserve_memory_special(size_t size, char* addr = NULL,
329 bool executable = false);
330 static bool release_memory_special(char* addr, size_t bytes);
331 static void large_page_init();
332 static size_t large_page_size();
333 static bool can_commit_large_page_memory();
334 static bool can_execute_large_page_memory();
335
336 // OS interface to polling page
337 static address get_polling_page() { return _polling_page; }
338 static void set_polling_page(address page) { _polling_page = page; }
339 static bool is_poll_address(address addr) { return addr >= _polling_page && addr < (_polling_page + os::vm_page_size()); }
340 static void make_polling_page_unreadable();
341 static void make_polling_page_readable();
342
343 // Routines used to serialize the thread state without using membars
344 static void serialize_thread_states();
345
346 // Since we write to the serialize page from every thread, we
347 // want stores to be on unique cache lines whenever possible
348 // in order to minimize CPU cross talk. We pre-compute the
349 // amount to shift the thread* to make this offset unique to
350 // each thread.
351 static int get_serialize_page_shift_count() {
352 return SerializePageShiftCount;
353 }
354
355 static void set_serialize_page_mask(uintptr_t mask) {
356 _serialize_page_mask = mask;
357 }
358
359 static unsigned int get_serialize_page_mask() {
360 return _serialize_page_mask;
361 }
362
363 static void set_memory_serialize_page(address page);
364
365 static address get_memory_serialize_page() {
366 return (address)_mem_serialize_page;
367 }
368
369 static inline void write_memory_serialize_page(JavaThread *thread) {
370 uintptr_t page_offset = ((uintptr_t)thread >>
371 get_serialize_page_shift_count()) &
372 get_serialize_page_mask();
373 *(volatile int32_t *)((uintptr_t)_mem_serialize_page+page_offset) = 1;
374 }
375
376 static bool is_memory_serialize_page(JavaThread *thread, address addr) {
377 if (UseMembar) return false;
378 // Previously this function calculated the exact address of this
379 // thread's serialize page, and checked if the faulting address
380 // was equal. However, some platforms mask off faulting addresses
381 // to the page size, so now we just check that the address is
382 // within the page. This makes the thread argument unnecessary,
383 // but we retain the NULL check to preserve existing behaviour.
384 if (thread == NULL) return false;
385 address page = (address) _mem_serialize_page;
386 return addr >= page && addr < (page + os::vm_page_size());
387 }
388
389 static void block_on_serialize_page_trap();
390
391 // threads
392
393 enum ThreadType {
394 vm_thread,
395 cgc_thread, // Concurrent GC thread
396 pgc_thread, // Parallel GC thread
397 java_thread,
398 compiler_thread,
399 watcher_thread,
400 os_thread
401 };
402
403 static bool create_thread(Thread* thread,
404 ThreadType thr_type,
405 size_t stack_size = 0);
406 static bool create_main_thread(JavaThread* thread);
407 static bool create_attached_thread(JavaThread* thread);
408 static void pd_start_thread(Thread* thread);
409 static void start_thread(Thread* thread);
410
411 static void initialize_thread(Thread* thr);
412 static void free_thread(OSThread* osthread);
413
414 // thread id on Linux/64bit is 64bit, on Windows and Solaris, it's 32bit
415 static intx current_thread_id();
416 static int current_process_id();
417 static int sleep(Thread* thread, jlong ms, bool interruptable);
418 static int naked_sleep();
419 static void infinite_sleep(); // never returns, use with CAUTION
420 static void yield(); // Yields to all threads with same priority
421 enum YieldResult {
422 YIELD_SWITCHED = 1, // caller descheduled, other ready threads exist & ran
423 YIELD_NONEREADY = 0, // No other runnable/ready threads.
424 // platform-specific yield return immediately
425 YIELD_UNKNOWN = -1 // Unknown: platform doesn't support _SWITCHED or _NONEREADY
426 // YIELD_SWITCHED and YIELD_NONREADY imply the platform supports a "strong"
427 // yield that can be used in lieu of blocking.
428 } ;
429 static YieldResult NakedYield () ;
430 static void yield_all(int attempts = 0); // Yields to all other threads including lower priority
431 static void loop_breaker(int attempts); // called from within tight loops to possibly influence time-sharing
432 static OSReturn set_priority(Thread* thread, ThreadPriority priority);
433 static OSReturn get_priority(const Thread* const thread, ThreadPriority& priority);
434
435 static void interrupt(Thread* thread);
436 static bool is_interrupted(Thread* thread, bool clear_interrupted);
437
438 static int pd_self_suspend_thread(Thread* thread);
439
440 static ExtendedPC fetch_frame_from_context(void* ucVoid, intptr_t** sp, intptr_t** fp);
441 static frame fetch_frame_from_context(void* ucVoid);
442
443 static ExtendedPC get_thread_pc(Thread *thread);
444 static void breakpoint();
445
446 static address current_stack_pointer();
447 static address current_stack_base();
448 static size_t current_stack_size();
449
450 static void verify_stack_alignment() PRODUCT_RETURN;
451
452 static int message_box(const char* title, const char* message);
453 static char* do_you_want_to_debug(const char* message);
454
455 // run cmd in a separate process and return its exit code; or -1 on failures
456 static int fork_and_exec(char *cmd);
457
458 // Set file to send error reports.
459 static void set_error_file(const char *logfile);
460
461 // os::exit() is merged with vm_exit()
462 // static void exit(int num);
463
464 // Terminate the VM, but don't exit the process
465 static void shutdown();
466
467 // Terminate with an error. Default is to generate a core file on platforms
468 // that support such things. This calls shutdown() and then aborts.
469 static void abort(bool dump_core = true);
470
471 // Die immediately, no exit hook, no abort hook, no cleanup.
472 static void die();
473
474 // File i/o operations
475 static const int default_file_open_flags();
476 static int open(const char *path, int oflag, int mode);
477 static FILE* open(int fd, const char* mode);
478 static int close(int fd);
479 static jlong lseek(int fd, jlong offset, int whence);
480 static char* native_path(char *path);
481 static int ftruncate(int fd, jlong length);
482 static int fsync(int fd);
483 static int available(int fd, jlong *bytes);
484
485 //File i/o operations
486
487 static size_t read(int fd, void *buf, unsigned int nBytes);
488 static size_t restartable_read(int fd, void *buf, unsigned int nBytes);
489 static size_t write(int fd, const void *buf, unsigned int nBytes);
490
491 // Reading directories.
492 static DIR* opendir(const char* dirname);
493 static int readdir_buf_size(const char *path);
494 static struct dirent* readdir(DIR* dirp, dirent* dbuf);
495 static int closedir(DIR* dirp);
496
497 // Dynamic library extension
498 static const char* dll_file_extension();
499
500 static const char* get_temp_directory();
501 static const char* get_current_directory(char *buf, size_t buflen);
502
503 // Builds a platform-specific full library path given a ld path and lib name
504 // Returns true if buffer contains full path to existing file, false otherwise
505 static bool dll_build_name(char* buffer, size_t size,
506 const char* pathname, const char* fname);
507
508 // Symbol lookup, find nearest function name; basically it implements
509 // dladdr() for all platforms. Name of the nearest function is copied
510 // to buf. Distance from its base address is optionally returned as offset.
511 // If function name is not found, buf[0] is set to '\0' and offset is
512 // set to -1 (if offset is non-NULL).
513 static bool dll_address_to_function_name(address addr, char* buf,
514 int buflen, int* offset);
515
516 // Locate DLL/DSO. On success, full path of the library is copied to
517 // buf, and offset is optionally set to be the distance between addr
518 // and the library's base address. On failure, buf[0] is set to '\0'
519 // and offset is set to -1 (if offset is non-NULL).
520 static bool dll_address_to_library_name(address addr, char* buf,
521 int buflen, int* offset);
522
523 // Find out whether the pc is in the static code for jvm.dll/libjvm.so.
524 static bool address_is_in_vm(address addr);
525
526 // Loads .dll/.so and
527 // in case of error it checks if .dll/.so was built for the
528 // same architecture as Hotspot is running on
529 static void* dll_load(const char *name, char *ebuf, int ebuflen);
530
531 // lookup symbol in a shared library
532 static void* dll_lookup(void* handle, const char* name);
533
534 // Unload library
535 static void dll_unload(void *lib);
536
537 // Print out system information; they are called by fatal error handler.
538 // Output format may be different on different platforms.
539 static void print_os_info(outputStream* st);
540 static void print_os_info_brief(outputStream* st);
541 static void print_cpu_info(outputStream* st);
542 static void pd_print_cpu_info(outputStream* st);
543 static void print_memory_info(outputStream* st);
544 static void print_dll_info(outputStream* st);
545 static void print_environment_variables(outputStream* st, const char** env_list, char* buffer, int len);
546 static void print_context(outputStream* st, void* context);
547 static void print_register_info(outputStream* st, void* context);
548 static void print_siginfo(outputStream* st, void* siginfo);
549 static void print_signal_handlers(outputStream* st, char* buf, size_t buflen);
550 static void print_date_and_time(outputStream* st);
551
552 static void print_location(outputStream* st, intptr_t x, bool verbose = false);
553 static size_t lasterror(char *buf, size_t len);
554 static int get_last_error();
555
556 // Determines whether the calling process is being debugged by a user-mode debugger.
557 static bool is_debugger_attached();
558
559 // wait for a key press if PauseAtExit is set
560 static void wait_for_keypress_at_exit(void);
561
562 // The following two functions are used by fatal error handler to trace
563 // native (C) frames. They are not part of frame.hpp/frame.cpp because
564 // frame.hpp/cpp assume thread is JavaThread, and also because different
565 // OS/compiler may have different convention or provide different API to
566 // walk C frames.
567 //
568 // We don't attempt to become a debugger, so we only follow frames if that
569 // does not require a lookup in the unwind table, which is part of the binary
570 // file but may be unsafe to read after a fatal error. So on x86, we can
571 // only walk stack if %ebp is used as frame pointer; on ia64, it's not
572 // possible to walk C stack without having the unwind table.
573 static bool is_first_C_frame(frame *fr);
574 static frame get_sender_for_C_frame(frame *fr);
575
576 // return current frame. pc() and sp() are set to NULL on failure.
577 static frame current_frame();
578
579 static void print_hex_dump(outputStream* st, address start, address end, int unitsize);
580
581 // returns a string to describe the exception/signal;
582 // returns NULL if exception_code is not an OS exception/signal.
583 static const char* exception_name(int exception_code, char* buf, size_t buflen);
584
585 // Returns native Java library, loads if necessary
586 static void* native_java_library();
587
588 // Fills in path to jvm.dll/libjvm.so (used by the Disassembler)
589 static void jvm_path(char *buf, jint buflen);
590
591 // Returns true if we are running in a headless jre.
592 static bool is_headless_jre();
593
594 // JNI names
595 static void print_jni_name_prefix_on(outputStream* st, int args_size);
596 static void print_jni_name_suffix_on(outputStream* st, int args_size);
597
598 // File conventions
599 static const char* file_separator();
600 static const char* line_separator();
601 static const char* path_separator();
602
603 // Init os specific system properties values
604 static void init_system_properties_values();
605
606 // IO operations, non-JVM_ version.
607 static int stat(const char* path, struct stat* sbuf);
608 static bool dir_is_empty(const char* path);
609
610 // IO operations on binary files
611 static int create_binary_file(const char* path, bool rewrite_existing);
612 static jlong current_file_offset(int fd);
613 static jlong seek_to_file_offset(int fd, jlong offset);
614
615 // Thread Local Storage
616 static int allocate_thread_local_storage();
617 static void thread_local_storage_at_put(int index, void* value);
618 static void* thread_local_storage_at(int index);
619 static void free_thread_local_storage(int index);
620
621 // Stack walk
622 static address get_caller_pc(int n = 0);
623
624 // General allocation (must be MT-safe)
625 static void* malloc (size_t size, MEMFLAGS flags, address caller_pc = 0);
626 static void* realloc (void *memblock, size_t size, MEMFLAGS flags, address caller_pc = 0);
627 static void free (void *memblock, MEMFLAGS flags = mtNone);
628 static bool check_heap(bool force = false); // verify C heap integrity
629 static char* strdup(const char *, MEMFLAGS flags = mtInternal); // Like strdup
630
631 #ifndef PRODUCT
632 static julong num_mallocs; // # of calls to malloc/realloc
633 static julong alloc_bytes; // # of bytes allocated
634 static julong num_frees; // # of calls to free
635 static julong free_bytes; // # of bytes freed
636 #endif
637
638 // SocketInterface (ex HPI SocketInterface )
639 static int socket(int domain, int type, int protocol);
640 static int socket_close(int fd);
641 static int socket_shutdown(int fd, int howto);
642 static int recv(int fd, char* buf, size_t nBytes, uint flags);
643 static int send(int fd, char* buf, size_t nBytes, uint flags);
644 static int raw_send(int fd, char* buf, size_t nBytes, uint flags);
645 static int timeout(int fd, long timeout);
646 static int listen(int fd, int count);
647 static int connect(int fd, struct sockaddr* him, socklen_t len);
648 static int bind(int fd, struct sockaddr* him, socklen_t len);
649 static int accept(int fd, struct sockaddr* him, socklen_t* len);
650 static int recvfrom(int fd, char* buf, size_t nbytes, uint flags,
651 struct sockaddr* from, socklen_t* fromlen);
652 static int get_sock_name(int fd, struct sockaddr* him, socklen_t* len);
653 static int sendto(int fd, char* buf, size_t len, uint flags,
654 struct sockaddr* to, socklen_t tolen);
655 static int socket_available(int fd, jint* pbytes);
656
657 static int get_sock_opt(int fd, int level, int optname,
658 char* optval, socklen_t* optlen);
659 static int set_sock_opt(int fd, int level, int optname,
660 const char* optval, socklen_t optlen);
661 static int get_host_name(char* name, int namelen);
662
663 static struct hostent* get_host_by_name(char* name);
664
665 // Support for signals (see JVM_RaiseSignal, JVM_RegisterSignal)
666 static void signal_init();
667 static void signal_init_pd();
668 static void signal_notify(int signal_number);
669 static void* signal(int signal_number, void* handler);
670 static void signal_raise(int signal_number);
671 static int signal_wait();
672 static int signal_lookup();
673 static void* user_handler();
674 static void terminate_signal_thread();
675 static int sigexitnum_pd();
676
677 // random number generation
678 static long random(); // return 32bit pseudorandom number
679 static void init_random(long initval); // initialize random sequence
680
681 // Structured OS Exception support
682 static void os_exception_wrapper(java_call_t f, JavaValue* value, methodHandle* method, JavaCallArguments* args, Thread* thread);
683
684 // On Windows this will create an actual minidump, on Linux/Solaris it will simply check core dump limits
685 static void check_or_create_dump(void* exceptionRecord, void* contextRecord, char* buffer, size_t bufferSize);
686
687 // Get the default path to the core file
688 // Returns the length of the string
689 static int get_core_path(char* buffer, size_t bufferSize);
690
691 // JVMTI & JVM monitoring and management support
692 // The thread_cpu_time() and current_thread_cpu_time() are only
693 // supported if is_thread_cpu_time_supported() returns true.
694 // They are not supported on Solaris T1.
695
696 // Thread CPU Time - return the fast estimate on a platform
697 // On Solaris - call gethrvtime (fast) - user time only
698 // On Linux - fast clock_gettime where available - user+sys
699 // - otherwise: very slow /proc fs - user+sys
700 // On Windows - GetThreadTimes - user+sys
701 static jlong current_thread_cpu_time();
702 static jlong thread_cpu_time(Thread* t);
703
704 // Thread CPU Time with user_sys_cpu_time parameter.
705 //
706 // If user_sys_cpu_time is true, user+sys time is returned.
707 // Otherwise, only user time is returned
708 static jlong current_thread_cpu_time(bool user_sys_cpu_time);
709 static jlong thread_cpu_time(Thread* t, bool user_sys_cpu_time);
710
711 // Return a bunch of info about the timers.
712 // Note that the returned info for these two functions may be different
713 // on some platforms
714 static void current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr);
715 static void thread_cpu_time_info(jvmtiTimerInfo *info_ptr);
716
717 static bool is_thread_cpu_time_supported();
718
719 // System loadavg support. Returns -1 if load average cannot be obtained.
720 static int loadavg(double loadavg[], int nelem);
721
722 // Hook for os specific jvm options that we don't want to abort on seeing
723 static bool obsolete_option(const JavaVMOption *option);
724
725 // Read file line by line. If line is longer than bsize,
726 // rest of line is skipped. Returns number of bytes read or -1 on EOF
727 static int get_line_chars(int fd, char *buf, const size_t bsize);
728
729 // Extensions
730 #include "runtime/os_ext.hpp"
731
732 public:
733
734 // Platform dependent stuff
735 #ifdef TARGET_OS_FAMILY_linux
736 # include "os_linux.hpp"
737 # include "os_posix.hpp"
738 #endif
739 #ifdef TARGET_OS_FAMILY_solaris
740 # include "os_solaris.hpp"
741 # include "os_posix.hpp"
742 #endif
743 #ifdef TARGET_OS_FAMILY_windows
744 # include "os_windows.hpp"
745 #endif
746 #ifdef TARGET_OS_FAMILY_bsd
747 # include "os_posix.hpp"
748 # include "os_bsd.hpp"
749 #endif
750 #ifdef TARGET_OS_ARCH_linux_x86
751 # include "os_linux_x86.hpp"
752 #endif
753 #ifdef TARGET_OS_ARCH_linux_sparc
754 # include "os_linux_sparc.hpp"
755 #endif
756 #ifdef TARGET_OS_ARCH_linux_zero
757 # include "os_linux_zero.hpp"
758 #endif
759 #ifdef TARGET_OS_ARCH_solaris_x86
760 # include "os_solaris_x86.hpp"
761 #endif
762 #ifdef TARGET_OS_ARCH_solaris_sparc
763 # include "os_solaris_sparc.hpp"
764 #endif
765 #ifdef TARGET_OS_ARCH_windows_x86
766 # include "os_windows_x86.hpp"
767 #endif
768 #ifdef TARGET_OS_ARCH_linux_arm
769 # include "os_linux_arm.hpp"
770 #endif
771 #ifdef TARGET_OS_ARCH_linux_ppc
772 # include "os_linux_ppc.hpp"
773 #endif
774 #ifdef TARGET_OS_ARCH_bsd_x86
775 # include "os_bsd_x86.hpp"
776 #endif
777 #ifdef TARGET_OS_ARCH_bsd_zero
778 # include "os_bsd_zero.hpp"
779 #endif
780
781 public:
782 // debugging support (mostly used by debug.cpp but also fatal error handler)
783 static bool find(address pc, outputStream* st = tty); // OS specific function to make sense out of an address
784
785 static bool dont_yield(); // when true, JVM_Yield() is nop
786 static void print_statistics();
787
788 // Thread priority helpers (implemented in OS-specific part)
789 static OSReturn set_native_priority(Thread* thread, int native_prio);
790 static OSReturn get_native_priority(const Thread* const thread, int* priority_ptr);
791 static int java_to_os_priority[CriticalPriority + 1];
792 // Hint to the underlying OS that a task switch would not be good.
793 // Void return because it's a hint and can fail.
794 static void hint_no_preempt();
795
796 // Used at creation if requested by the diagnostic flag PauseAtStartup.
797 // Causes the VM to wait until an external stimulus has been applied
798 // (for Unix, that stimulus is a signal, for Windows, an external
799 // ResumeThread call)
800 static void pause();
801
802 class SuspendedThreadTaskContext {
803 public:
804 SuspendedThreadTaskContext(Thread* thread, void *ucontext) : _thread(thread), _ucontext(ucontext) {}
805 Thread* thread() const { return _thread; }
806 void* ucontext() const { return _ucontext; }
807 private:
808 Thread* _thread;
809 void* _ucontext;
810 };
811
812 class SuspendedThreadTask {
813 public:
814 SuspendedThreadTask(Thread* thread) : _thread(thread), _done(false) {}
815 virtual ~SuspendedThreadTask() {}
816 void run();
817 bool is_done() { return _done; }
818 virtual void do_task(const SuspendedThreadTaskContext& context) = 0;
819 protected:
820 private:
821 void internal_do_task();
822 Thread* _thread;
823 bool _done;
824 };
825
826 #ifndef TARGET_OS_FAMILY_windows
827 // Suspend/resume support
828 // Protocol:
829 //
830 // a thread starts in SR_RUNNING
831 //
832 // SR_RUNNING can go to
833 // * SR_SUSPEND_REQUEST when the WatcherThread wants to suspend it
834 // SR_SUSPEND_REQUEST can go to
835 // * SR_RUNNING if WatcherThread decides it waited for SR_SUSPENDED too long (timeout)
836 // * SR_SUSPENDED if the stopped thread receives the signal and switches state
837 // SR_SUSPENDED can go to
838 // * SR_WAKEUP_REQUEST when the WatcherThread has done the work and wants to resume
839 // SR_WAKEUP_REQUEST can go to
840 // * SR_RUNNING when the stopped thread receives the signal
841 // * SR_WAKEUP_REQUEST on timeout (resend the signal and try again)
842 class SuspendResume {
843 public:
844 enum State {
845 SR_RUNNING,
846 SR_SUSPEND_REQUEST,
847 SR_SUSPENDED,
848 SR_WAKEUP_REQUEST
849 };
850
851 private:
852 volatile State _state;
853
854 private:
855 /* try to switch state from state "from" to state "to"
856 * returns the state set after the method is complete
857 */
858 State switch_state(State from, State to);
859
860 public:
861 SuspendResume() : _state(SR_RUNNING) { }
862
863 State state() const { return _state; }
864
865 State request_suspend() {
866 return switch_state(SR_RUNNING, SR_SUSPEND_REQUEST);
867 }
868
869 State cancel_suspend() {
870 return switch_state(SR_SUSPEND_REQUEST, SR_RUNNING);
871 }
872
873 State suspended() {
874 return switch_state(SR_SUSPEND_REQUEST, SR_SUSPENDED);
875 }
876
877 State request_wakeup() {
878 return switch_state(SR_SUSPENDED, SR_WAKEUP_REQUEST);
879 }
880
881 State running() {
882 return switch_state(SR_WAKEUP_REQUEST, SR_RUNNING);
883 }
884
885 bool is_running() const {
886 return _state == SR_RUNNING;
887 }
888
889 bool is_suspend_request() const {
890 return _state == SR_SUSPEND_REQUEST;
891 }
892
893 bool is_suspended() const {
894 return _state == SR_SUSPENDED;
895 }
896 };
897 #endif
898
899
900 protected:
901 static long _rand_seed; // seed for random number generator
902 static int _processor_count; // number of processors
903
904 static char* format_boot_path(const char* format_string,
905 const char* home,
906 int home_len,
907 char fileSep,
908 char pathSep);
909 static bool set_boot_path(char fileSep, char pathSep);
910 static char** split_path(const char* path, int* n);
911 };
912
913 // Note that "PAUSE" is almost always used with synchronization
914 // so arguably we should provide Atomic::SpinPause() instead
915 // of the global SpinPause() with C linkage.
916 // It'd also be eligible for inlining on many platforms.
917
918 extern "C" int SpinPause () ;
919 extern "C" int SafeFetch32 (int * adr, int errValue) ;
920 extern "C" intptr_t SafeFetchN (intptr_t * adr, intptr_t errValue) ;
921
922 #endif // SHARE_VM_RUNTIME_OS_HPP