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 # include <setjmp.h>
36 #endif
37 #ifdef TARGET_OS_FAMILY_solaris
38 # include "jvm_solaris.h"
39 # include <setjmp.h>
40 #endif
41 #ifdef TARGET_OS_FAMILY_windows
42 # include "jvm_windows.h"
43 #endif
44 #ifdef TARGET_OS_FAMILY_bsd
45 # include "jvm_bsd.h"
46 # include <setjmp.h>
47 #endif
48
49 // os defines the interface to operating system; this includes traditional
50 // OS services (time, I/O) as well as other functionality with system-
51 // dependent code.
52
53 typedef void (*dll_func)(...);
54
55 class Thread;
56 class JavaThread;
57 class Event;
58 class DLL;
59 class FileHandle;
60 template<class E> class GrowableArray;
61
62 // %%%%% Moved ThreadState, START_FN, OSThread to new osThread.hpp. -- Rose
63
64 // Platform-independent error return values from OS functions
65 enum OSReturn {
66 OS_OK = 0, // Operation was successful
67 OS_ERR = -1, // Operation failed
68 OS_INTRPT = -2, // Operation was interrupted
69 OS_TIMEOUT = -3, // Operation timed out
70 OS_NOMEM = -5, // Operation failed for lack of memory
71 OS_NORESOURCE = -6 // Operation failed for lack of nonmemory resource
72 };
73
74 enum ThreadPriority { // JLS 20.20.1-3
75 NoPriority = -1, // Initial non-priority value
76 MinPriority = 1, // Minimum priority
77 NormPriority = 5, // Normal (non-daemon) priority
78 NearMaxPriority = 9, // High priority, used for VMThread
79 MaxPriority = 10, // Highest priority, used for WatcherThread
80 // ensures that VMThread doesn't starve profiler
81 CriticalPriority = 11 // Critical thread priority
82 };
83
84 // Executable parameter flag for os::commit_memory() and
85 // os::commit_memory_or_exit().
86 const bool ExecMem = true;
87
88 // Typedef for structured exception handling support
89 typedef void (*java_call_t)(JavaValue* value, methodHandle* method, JavaCallArguments* args, Thread* thread);
90
91 class os: AllStatic {
92 public:
93 enum { page_sizes_max = 9 }; // Size of _page_sizes array (8 plus a sentinel)
94
95 private:
96 static OSThread* _starting_thread;
97 static address _polling_page;
98 static volatile int32_t * _mem_serialize_page;
99 static uintptr_t _serialize_page_mask;
100 public:
101 static size_t _page_sizes[page_sizes_max];
102
103 private:
104 static void init_page_sizes(size_t default_page_size) {
105 _page_sizes[0] = default_page_size;
106 _page_sizes[1] = 0; // sentinel
107 }
108
109 static char* pd_reserve_memory(size_t bytes, char* addr = 0,
110 size_t alignment_hint = 0);
111 static char* pd_attempt_reserve_memory_at(size_t bytes, char* addr);
112 static void pd_split_reserved_memory(char *base, size_t size,
113 size_t split, bool realloc);
114 static bool pd_commit_memory(char* addr, size_t bytes, bool executable);
115 static bool pd_commit_memory(char* addr, size_t size, size_t alignment_hint,
116 bool executable);
117 // Same as pd_commit_memory() that either succeeds or calls
118 // vm_exit_out_of_memory() with the specified mesg.
119 static void pd_commit_memory_or_exit(char* addr, size_t bytes,
120 bool executable, const char* mesg);
121 static void pd_commit_memory_or_exit(char* addr, size_t size,
122 size_t alignment_hint,
123 bool executable, const char* mesg);
124 static bool pd_uncommit_memory(char* addr, size_t bytes);
125 static bool pd_release_memory(char* addr, size_t bytes);
126
127 static char* pd_map_memory(int fd, const char* file_name, size_t file_offset,
128 char *addr, size_t bytes, bool read_only = false,
129 bool allow_exec = false);
130 static char* pd_remap_memory(int fd, const char* file_name, size_t file_offset,
131 char *addr, size_t bytes, bool read_only,
132 bool allow_exec);
133 static bool pd_unmap_memory(char *addr, size_t bytes);
134 static void pd_free_memory(char *addr, size_t bytes, size_t alignment_hint);
135 static void pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint);
136
137
138 public:
139 static void init(void); // Called before command line parsing
140 static jint init_2(void); // Called after command line parsing
141 static void init_globals(void) { // Called from init_globals() in init.cpp
142 init_globals_ext();
143 }
144 static void init_3(void); // Called at the end of vm init
145
146 // File names are case-insensitive on windows only
147 // Override me as needed
148 static int file_name_strcmp(const char* s1, const char* s2);
149
150 static bool getenv(const char* name, char* buffer, int len);
151 static bool have_special_privileges();
152
153 static jlong javaTimeMillis();
154 static jlong javaTimeNanos();
155 static void javaTimeNanos_info(jvmtiTimerInfo *info_ptr);
156 static void run_periodic_checks();
157
158
159 // Returns the elapsed time in seconds since the vm started.
160 static double elapsedTime();
161
162 // Returns real time in seconds since an arbitrary point
163 // in the past.
164 static bool getTimesSecs(double* process_real_time,
165 double* process_user_time,
166 double* process_system_time);
167
168 // Interface to the performance counter
169 static jlong elapsed_counter();
170 static jlong elapsed_frequency();
171
172 // The "virtual time" of a thread is the amount of time a thread has
173 // actually run. The first function indicates whether the OS supports
174 // this functionality for the current thread, and if so:
175 // * the second enables vtime tracking (if that is required).
176 // * the third tells whether vtime is enabled.
177 // * the fourth returns the elapsed virtual time for the current
178 // thread.
179 static bool supports_vtime();
180 static bool enable_vtime();
181 static bool vtime_enabled();
182 static double elapsedVTime();
183
184 // Return current local time in a string (YYYY-MM-DD HH:MM:SS).
185 // It is MT safe, but not async-safe, as reading time zone
186 // information may require a lock on some platforms.
187 static char* local_time_string(char *buf, size_t buflen);
188 static struct tm* localtime_pd (const time_t* clock, struct tm* res);
189 // Fill in buffer with current local time as an ISO-8601 string.
190 // E.g., YYYY-MM-DDThh:mm:ss.mmm+zzzz.
191 // Returns buffer, or NULL if it failed.
192 static char* iso8601_time(char* buffer, size_t buffer_length);
193
194 // Interface for detecting multiprocessor system
195 static inline bool is_MP() {
196 assert(_processor_count > 0, "invalid processor count");
197 return _processor_count > 1 || AssumeMP;
198 }
199 static julong available_memory();
200 static julong physical_memory();
201 static bool has_allocatable_memory_limit(julong* limit);
202 static bool is_server_class_machine();
203
204 // number of CPUs
205 static int processor_count() {
206 return _processor_count;
207 }
208 static void set_processor_count(int count) { _processor_count = count; }
209
210 // Returns the number of CPUs this process is currently allowed to run on.
211 // Note that on some OSes this can change dynamically.
212 static int active_processor_count();
213
214 // Bind processes to processors.
215 // This is a two step procedure:
216 // first you generate a distribution of processes to processors,
217 // then you bind processes according to that distribution.
218 // Compute a distribution for number of processes to processors.
219 // Stores the processor id's into the distribution array argument.
220 // Returns true if it worked, false if it didn't.
221 static bool distribute_processes(uint length, uint* distribution);
222 // Binds the current process to a processor.
223 // Returns true if it worked, false if it didn't.
224 static bool bind_to_processor(uint processor_id);
225
226 // Give a name to the current thread.
227 static void set_native_thread_name(const char *name);
228
229 // Interface for stack banging (predetect possible stack overflow for
230 // exception processing) There are guard pages, and above that shadow
231 // pages for stack overflow checking.
232 static bool uses_stack_guard_pages();
233 static bool allocate_stack_guard_pages();
234 static void bang_stack_shadow_pages();
235 static bool stack_shadow_pages_available(Thread *thread, methodHandle method);
236
237 // OS interface to Virtual Memory
238
239 // Return the default page size.
240 static int vm_page_size();
241
242 // Return the page size to use for a region of memory. The min_pages argument
243 // is a hint intended to limit fragmentation; it says the returned page size
244 // should be <= region_max_size / min_pages. Because min_pages is a hint,
245 // this routine may return a size larger than region_max_size / min_pages.
246 //
247 // The current implementation ignores min_pages if a larger page size is an
248 // exact multiple of both region_min_size and region_max_size. This allows
249 // larger pages to be used when doing so would not cause fragmentation; in
250 // particular, a single page can be used when region_min_size ==
251 // region_max_size == a supported page size.
252 static size_t page_size_for_region(size_t region_min_size,
253 size_t region_max_size,
254 uint min_pages);
255
256 // Methods for tracing page sizes returned by the above method; enabled by
257 // TracePageSizes. The region_{min,max}_size parameters should be the values
258 // passed to page_size_for_region() and page_size should be the result of that
259 // call. The (optional) base and size parameters should come from the
260 // ReservedSpace base() and size() methods.
261 static void trace_page_sizes(const char* str, const size_t* page_sizes,
262 int count) PRODUCT_RETURN;
263 static void trace_page_sizes(const char* str, const size_t region_min_size,
264 const size_t region_max_size,
265 const size_t page_size,
266 const char* base = NULL,
267 const size_t size = 0) PRODUCT_RETURN;
268
269 static int vm_allocation_granularity();
270 static char* reserve_memory(size_t bytes, char* addr = 0,
271 size_t alignment_hint = 0);
272 static char* reserve_memory(size_t bytes, char* addr,
273 size_t alignment_hint, MEMFLAGS flags);
274 static char* reserve_memory_aligned(size_t size, size_t alignment);
275 static char* attempt_reserve_memory_at(size_t bytes, char* addr);
276 static void split_reserved_memory(char *base, size_t size,
277 size_t split, bool realloc);
278 static bool commit_memory(char* addr, size_t bytes, bool executable);
279 static bool commit_memory(char* addr, size_t size, size_t alignment_hint,
280 bool executable);
281 // Same as commit_memory() that either succeeds or calls
282 // vm_exit_out_of_memory() with the specified mesg.
283 static void commit_memory_or_exit(char* addr, size_t bytes,
284 bool executable, const char* mesg);
285 static void commit_memory_or_exit(char* addr, size_t size,
286 size_t alignment_hint,
287 bool executable, const char* mesg);
288 static bool uncommit_memory(char* addr, size_t bytes);
289 static bool release_memory(char* addr, size_t bytes);
290
291 enum ProtType { MEM_PROT_NONE, MEM_PROT_READ, MEM_PROT_RW, MEM_PROT_RWX };
292 static bool protect_memory(char* addr, size_t bytes, ProtType prot,
293 bool is_committed = true);
294
295 static bool guard_memory(char* addr, size_t bytes);
296 static bool unguard_memory(char* addr, size_t bytes);
297 static bool create_stack_guard_pages(char* addr, size_t bytes);
298 static bool pd_create_stack_guard_pages(char* addr, size_t bytes);
299 static bool remove_stack_guard_pages(char* addr, size_t bytes);
300
301 static char* map_memory(int fd, const char* file_name, size_t file_offset,
302 char *addr, size_t bytes, bool read_only = false,
303 bool allow_exec = false);
304 static char* remap_memory(int fd, const char* file_name, size_t file_offset,
305 char *addr, size_t bytes, bool read_only,
306 bool allow_exec);
307 static bool unmap_memory(char *addr, size_t bytes);
308 static void free_memory(char *addr, size_t bytes, size_t alignment_hint);
309 static void realign_memory(char *addr, size_t bytes, size_t alignment_hint);
310
311 // NUMA-specific interface
312 static bool numa_has_static_binding();
313 static bool numa_has_group_homing();
314 static void numa_make_local(char *addr, size_t bytes, int lgrp_hint);
315 static void numa_make_global(char *addr, size_t bytes);
316 static size_t numa_get_groups_num();
317 static size_t numa_get_leaf_groups(int *ids, size_t size);
318 static bool numa_topology_changed();
319 static int numa_get_group_id();
320
321 // Page manipulation
322 struct page_info {
323 size_t size;
324 int lgrp_id;
325 };
326 static bool get_page_info(char *start, page_info* info);
327 static char* scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found);
328
329 static char* non_memory_address_word();
330 // reserve, commit and pin the entire memory region
331 static char* reserve_memory_special(size_t size, char* addr = NULL,
332 bool executable = false);
333 static bool release_memory_special(char* addr, size_t bytes);
334 static void large_page_init();
335 static size_t large_page_size();
336 static bool can_commit_large_page_memory();
337 static bool can_execute_large_page_memory();
338
339 // OS interface to polling page
340 static address get_polling_page() { return _polling_page; }
341 static void set_polling_page(address page) { _polling_page = page; }
342 static bool is_poll_address(address addr) { return addr >= _polling_page && addr < (_polling_page + os::vm_page_size()); }
343 static void make_polling_page_unreadable();
344 static void make_polling_page_readable();
345
346 // Routines used to serialize the thread state without using membars
347 static void serialize_thread_states();
348
349 // Since we write to the serialize page from every thread, we
350 // want stores to be on unique cache lines whenever possible
351 // in order to minimize CPU cross talk. We pre-compute the
352 // amount to shift the thread* to make this offset unique to
353 // each thread.
354 static int get_serialize_page_shift_count() {
355 return SerializePageShiftCount;
356 }
357
358 static void set_serialize_page_mask(uintptr_t mask) {
359 _serialize_page_mask = mask;
360 }
361
362 static unsigned int get_serialize_page_mask() {
363 return _serialize_page_mask;
364 }
365
366 static void set_memory_serialize_page(address page);
367
368 static address get_memory_serialize_page() {
369 return (address)_mem_serialize_page;
370 }
371
372 static inline void write_memory_serialize_page(JavaThread *thread) {
373 uintptr_t page_offset = ((uintptr_t)thread >>
374 get_serialize_page_shift_count()) &
375 get_serialize_page_mask();
376 *(volatile int32_t *)((uintptr_t)_mem_serialize_page+page_offset) = 1;
377 }
378
379 static bool is_memory_serialize_page(JavaThread *thread, address addr) {
380 if (UseMembar) return false;
381 // Previously this function calculated the exact address of this
382 // thread's serialize page, and checked if the faulting address
383 // was equal. However, some platforms mask off faulting addresses
384 // to the page size, so now we just check that the address is
385 // within the page. This makes the thread argument unnecessary,
386 // but we retain the NULL check to preserve existing behaviour.
387 if (thread == NULL) return false;
388 address page = (address) _mem_serialize_page;
389 return addr >= page && addr < (page + os::vm_page_size());
390 }
391
392 static void block_on_serialize_page_trap();
393
394 // threads
395
396 enum ThreadType {
397 vm_thread,
398 cgc_thread, // Concurrent GC thread
399 pgc_thread, // Parallel GC thread
400 java_thread,
401 compiler_thread,
402 watcher_thread,
403 os_thread
404 };
405
406 static bool create_thread(Thread* thread,
407 ThreadType thr_type,
408 size_t stack_size = 0);
409 static bool create_main_thread(JavaThread* thread);
410 static bool create_attached_thread(JavaThread* thread);
411 static void pd_start_thread(Thread* thread);
412 static void start_thread(Thread* thread);
413
414 static void initialize_thread(Thread* thr);
415 static void free_thread(OSThread* osthread);
416
417 // thread id on Linux/64bit is 64bit, on Windows and Solaris, it's 32bit
418 static intx current_thread_id();
419 static int current_process_id();
420 static int sleep(Thread* thread, jlong ms, bool interruptable);
421 static int naked_sleep();
422 static void infinite_sleep(); // never returns, use with CAUTION
423 static void yield(); // Yields to all threads with same priority
424 enum YieldResult {
425 YIELD_SWITCHED = 1, // caller descheduled, other ready threads exist & ran
426 YIELD_NONEREADY = 0, // No other runnable/ready threads.
427 // platform-specific yield return immediately
428 YIELD_UNKNOWN = -1 // Unknown: platform doesn't support _SWITCHED or _NONEREADY
429 // YIELD_SWITCHED and YIELD_NONREADY imply the platform supports a "strong"
430 // yield that can be used in lieu of blocking.
431 } ;
432 static YieldResult NakedYield () ;
433 static void yield_all(int attempts = 0); // Yields to all other threads including lower priority
434 static void loop_breaker(int attempts); // called from within tight loops to possibly influence time-sharing
435 static OSReturn set_priority(Thread* thread, ThreadPriority priority);
436 static OSReturn get_priority(const Thread* const thread, ThreadPriority& priority);
437
438 static void interrupt(Thread* thread);
439 static bool is_interrupted(Thread* thread, bool clear_interrupted);
440
441 static int pd_self_suspend_thread(Thread* thread);
442
443 static ExtendedPC fetch_frame_from_context(void* ucVoid, intptr_t** sp, intptr_t** fp);
444 static frame fetch_frame_from_context(void* ucVoid);
445
446 static ExtendedPC get_thread_pc(Thread *thread);
447 static void breakpoint();
448
449 static address current_stack_pointer();
450 static address current_stack_base();
451 static size_t current_stack_size();
452
453 static void verify_stack_alignment() PRODUCT_RETURN;
454
455 static int message_box(const char* title, const char* message);
456 static char* do_you_want_to_debug(const char* message);
457
458 // run cmd in a separate process and return its exit code; or -1 on failures
459 static int fork_and_exec(char *cmd);
460
461 // Set file to send error reports.
462 static void set_error_file(const char *logfile);
463
464 // os::exit() is merged with vm_exit()
465 // static void exit(int num);
466
467 // Terminate the VM, but don't exit the process
468 static void shutdown();
469
470 // Terminate with an error. Default is to generate a core file on platforms
471 // that support such things. This calls shutdown() and then aborts.
472 static void abort(bool dump_core = true);
473
474 // Die immediately, no exit hook, no abort hook, no cleanup.
475 static void die();
476
477 // File i/o operations
478 static const int default_file_open_flags();
479 static int open(const char *path, int oflag, int mode);
480 static FILE* open(int fd, const char* mode);
481 static int close(int fd);
482 static jlong lseek(int fd, jlong offset, int whence);
483 static char* native_path(char *path);
484 static int ftruncate(int fd, jlong length);
485 static int fsync(int fd);
486 static int available(int fd, jlong *bytes);
487
488 //File i/o operations
489
490 static size_t read(int fd, void *buf, unsigned int nBytes);
491 static size_t restartable_read(int fd, void *buf, unsigned int nBytes);
492 static size_t write(int fd, const void *buf, unsigned int nBytes);
493
494 // Reading directories.
495 static DIR* opendir(const char* dirname);
496 static int readdir_buf_size(const char *path);
497 static struct dirent* readdir(DIR* dirp, dirent* dbuf);
498 static int closedir(DIR* dirp);
499
500 // Dynamic library extension
501 static const char* dll_file_extension();
502
503 static const char* get_temp_directory();
504 static const char* get_current_directory(char *buf, size_t buflen);
505
506 // Builds a platform-specific full library path given a ld path and lib name
507 // Returns true if buffer contains full path to existing file, false otherwise
508 static bool dll_build_name(char* buffer, size_t size,
509 const char* pathname, const char* fname);
510
511 // Symbol lookup, find nearest function name; basically it implements
512 // dladdr() for all platforms. Name of the nearest function is copied
513 // to buf. Distance from its base address is optionally returned as offset.
514 // If function name is not found, buf[0] is set to '\0' and offset is
515 // set to -1 (if offset is non-NULL).
516 static bool dll_address_to_function_name(address addr, char* buf,
517 int buflen, int* offset);
518
519 // Locate DLL/DSO. On success, full path of the library is copied to
520 // buf, and offset is optionally set to be the distance between addr
521 // and the library's base address. On failure, buf[0] is set to '\0'
522 // and offset is set to -1 (if offset is non-NULL).
523 static bool dll_address_to_library_name(address addr, char* buf,
524 int buflen, int* offset);
525
526 // Find out whether the pc is in the static code for jvm.dll/libjvm.so.
527 static bool address_is_in_vm(address addr);
528
529 // Loads .dll/.so and
530 // in case of error it checks if .dll/.so was built for the
531 // same architecture as Hotspot is running on
532 static void* dll_load(const char *name, char *ebuf, int ebuflen);
533
534 // lookup symbol in a shared library
535 static void* dll_lookup(void* handle, const char* name);
536
537 // Unload library
538 static void dll_unload(void *lib);
539
540 // Print out system information; they are called by fatal error handler.
541 // Output format may be different on different platforms.
542 static void print_os_info(outputStream* st);
543 static void print_os_info_brief(outputStream* st);
544 static void print_cpu_info(outputStream* st);
545 static void pd_print_cpu_info(outputStream* st);
546 static void print_memory_info(outputStream* st);
547 static void print_dll_info(outputStream* st);
548 static void print_environment_variables(outputStream* st, const char** env_list, char* buffer, int len);
549 static void print_context(outputStream* st, void* context);
550 static void print_register_info(outputStream* st, void* context);
551 static void print_siginfo(outputStream* st, void* siginfo);
552 static void print_signal_handlers(outputStream* st, char* buf, size_t buflen);
553 static void print_date_and_time(outputStream* st);
554
555 static void print_location(outputStream* st, intptr_t x, bool verbose = false);
556 static size_t lasterror(char *buf, size_t len);
557 static int get_last_error();
558
559 // Determines whether the calling process is being debugged by a user-mode debugger.
560 static bool is_debugger_attached();
561
562 // wait for a key press if PauseAtExit is set
563 static void wait_for_keypress_at_exit(void);
564
565 // The following two functions are used by fatal error handler to trace
566 // native (C) frames. They are not part of frame.hpp/frame.cpp because
567 // frame.hpp/cpp assume thread is JavaThread, and also because different
568 // OS/compiler may have different convention or provide different API to
569 // walk C frames.
570 //
571 // We don't attempt to become a debugger, so we only follow frames if that
572 // does not require a lookup in the unwind table, which is part of the binary
573 // file but may be unsafe to read after a fatal error. So on x86, we can
574 // only walk stack if %ebp is used as frame pointer; on ia64, it's not
575 // possible to walk C stack without having the unwind table.
576 static bool is_first_C_frame(frame *fr);
577 static frame get_sender_for_C_frame(frame *fr);
578
579 // return current frame. pc() and sp() are set to NULL on failure.
580 static frame current_frame();
581
582 static void print_hex_dump(outputStream* st, address start, address end, int unitsize);
583
584 // returns a string to describe the exception/signal;
585 // returns NULL if exception_code is not an OS exception/signal.
586 static const char* exception_name(int exception_code, char* buf, size_t buflen);
587
588 // Returns native Java library, loads if necessary
589 static void* native_java_library();
590
591 // Fills in path to jvm.dll/libjvm.so (used by the Disassembler)
592 static void jvm_path(char *buf, jint buflen);
593
594 // Returns true if we are running in a headless jre.
595 static bool is_headless_jre();
596
597 // JNI names
598 static void print_jni_name_prefix_on(outputStream* st, int args_size);
599 static void print_jni_name_suffix_on(outputStream* st, int args_size);
600
601 // File conventions
602 static const char* file_separator();
603 static const char* line_separator();
604 static const char* path_separator();
605
606 // Init os specific system properties values
607 static void init_system_properties_values();
608
609 // IO operations, non-JVM_ version.
610 static int stat(const char* path, struct stat* sbuf);
611 static bool dir_is_empty(const char* path);
612
613 // IO operations on binary files
614 static int create_binary_file(const char* path, bool rewrite_existing);
615 static jlong current_file_offset(int fd);
616 static jlong seek_to_file_offset(int fd, jlong offset);
617
618 // Thread Local Storage
619 static int allocate_thread_local_storage();
620 static void thread_local_storage_at_put(int index, void* value);
621 static void* thread_local_storage_at(int index);
622 static void free_thread_local_storage(int index);
623
624 // Stack walk
625 static address get_caller_pc(int n = 0);
626
627 // General allocation (must be MT-safe)
628 static void* malloc (size_t size, MEMFLAGS flags, address caller_pc = 0);
629 static void* realloc (void *memblock, size_t size, MEMFLAGS flags, address caller_pc = 0);
630 static void free (void *memblock, MEMFLAGS flags = mtNone);
631 static bool check_heap(bool force = false); // verify C heap integrity
632 static char* strdup(const char *, MEMFLAGS flags = mtInternal); // Like strdup
633
634 #ifndef PRODUCT
635 static julong num_mallocs; // # of calls to malloc/realloc
636 static julong alloc_bytes; // # of bytes allocated
637 static julong num_frees; // # of calls to free
638 static julong free_bytes; // # of bytes freed
639 #endif
640
641 // SocketInterface (ex HPI SocketInterface )
642 static int socket(int domain, int type, int protocol);
643 static int socket_close(int fd);
644 static int socket_shutdown(int fd, int howto);
645 static int recv(int fd, char* buf, size_t nBytes, uint flags);
646 static int send(int fd, char* buf, size_t nBytes, uint flags);
647 static int raw_send(int fd, char* buf, size_t nBytes, uint flags);
648 static int timeout(int fd, long timeout);
649 static int listen(int fd, int count);
650 static int connect(int fd, struct sockaddr* him, socklen_t len);
651 static int bind(int fd, struct sockaddr* him, socklen_t len);
652 static int accept(int fd, struct sockaddr* him, socklen_t* len);
653 static int recvfrom(int fd, char* buf, size_t nbytes, uint flags,
654 struct sockaddr* from, socklen_t* fromlen);
655 static int get_sock_name(int fd, struct sockaddr* him, socklen_t* len);
656 static int sendto(int fd, char* buf, size_t len, uint flags,
657 struct sockaddr* to, socklen_t tolen);
658 static int socket_available(int fd, jint* pbytes);
659
660 static int get_sock_opt(int fd, int level, int optname,
661 char* optval, socklen_t* optlen);
662 static int set_sock_opt(int fd, int level, int optname,
663 const char* optval, socklen_t optlen);
664 static int get_host_name(char* name, int namelen);
665
666 static struct hostent* get_host_by_name(char* name);
667
668 // Support for signals (see JVM_RaiseSignal, JVM_RegisterSignal)
669 static void signal_init();
670 static void signal_init_pd();
671 static void signal_notify(int signal_number);
672 static void* signal(int signal_number, void* handler);
673 static void signal_raise(int signal_number);
674 static int signal_wait();
675 static int signal_lookup();
676 static void* user_handler();
677 static void terminate_signal_thread();
678 static int sigexitnum_pd();
679
680 // random number generation
681 static long random(); // return 32bit pseudorandom number
682 static void init_random(long initval); // initialize random sequence
683
684 // Structured OS Exception support
685 static void os_exception_wrapper(java_call_t f, JavaValue* value, methodHandle* method, JavaCallArguments* args, Thread* thread);
686
687 // On Windows this will create an actual minidump, on Linux/Solaris it will simply check core dump limits
688 static void check_or_create_dump(void* exceptionRecord, void* contextRecord, char* buffer, size_t bufferSize);
689
690 // Get the default path to the core file
691 // Returns the length of the string
692 static int get_core_path(char* buffer, size_t bufferSize);
693
694 // JVMTI & JVM monitoring and management support
695 // The thread_cpu_time() and current_thread_cpu_time() are only
696 // supported if is_thread_cpu_time_supported() returns true.
697 // They are not supported on Solaris T1.
698
699 // Thread CPU Time - return the fast estimate on a platform
700 // On Solaris - call gethrvtime (fast) - user time only
701 // On Linux - fast clock_gettime where available - user+sys
702 // - otherwise: very slow /proc fs - user+sys
703 // On Windows - GetThreadTimes - user+sys
704 static jlong current_thread_cpu_time();
705 static jlong thread_cpu_time(Thread* t);
706
707 // Thread CPU Time with user_sys_cpu_time parameter.
708 //
709 // If user_sys_cpu_time is true, user+sys time is returned.
710 // Otherwise, only user time is returned
711 static jlong current_thread_cpu_time(bool user_sys_cpu_time);
712 static jlong thread_cpu_time(Thread* t, bool user_sys_cpu_time);
713
714 // Return a bunch of info about the timers.
715 // Note that the returned info for these two functions may be different
716 // on some platforms
717 static void current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr);
718 static void thread_cpu_time_info(jvmtiTimerInfo *info_ptr);
719
720 static bool is_thread_cpu_time_supported();
721
722 // System loadavg support. Returns -1 if load average cannot be obtained.
723 static int loadavg(double loadavg[], int nelem);
724
725 // Hook for os specific jvm options that we don't want to abort on seeing
726 static bool obsolete_option(const JavaVMOption *option);
727
728 // Read file line by line. If line is longer than bsize,
729 // rest of line is skipped. Returns number of bytes read or -1 on EOF
730 static int get_line_chars(int fd, char *buf, const size_t bsize);
731
732 // Extensions
733 #include "runtime/os_ext.hpp"
734
735 public:
736 class CrashProtectionCallback : public StackObj {
737 public:
738 virtual void call() = 0;
739 };
740
741 // Platform dependent stuff
742 #ifdef TARGET_OS_FAMILY_linux
743 # include "os_linux.hpp"
744 # include "os_posix.hpp"
745 #endif
746 #ifdef TARGET_OS_FAMILY_solaris
747 # include "os_solaris.hpp"
748 # include "os_posix.hpp"
749 #endif
750 #ifdef TARGET_OS_FAMILY_windows
751 # include "os_windows.hpp"
752 #endif
753 #ifdef TARGET_OS_FAMILY_bsd
754 # include "os_posix.hpp"
755 # include "os_bsd.hpp"
756 #endif
757 #ifdef TARGET_OS_ARCH_linux_x86
758 # include "os_linux_x86.hpp"
759 #endif
760 #ifdef TARGET_OS_ARCH_linux_sparc
761 # include "os_linux_sparc.hpp"
762 #endif
763 #ifdef TARGET_OS_ARCH_linux_zero
764 # include "os_linux_zero.hpp"
765 #endif
766 #ifdef TARGET_OS_ARCH_solaris_x86
767 # include "os_solaris_x86.hpp"
768 #endif
769 #ifdef TARGET_OS_ARCH_solaris_sparc
770 # include "os_solaris_sparc.hpp"
771 #endif
772 #ifdef TARGET_OS_ARCH_windows_x86
773 # include "os_windows_x86.hpp"
774 #endif
775 #ifdef TARGET_OS_ARCH_linux_arm
776 # include "os_linux_arm.hpp"
777 #endif
778 #ifdef TARGET_OS_ARCH_linux_ppc
779 # include "os_linux_ppc.hpp"
780 #endif
781 #ifdef TARGET_OS_ARCH_bsd_x86
782 # include "os_bsd_x86.hpp"
783 #endif
784 #ifdef TARGET_OS_ARCH_bsd_zero
785 # include "os_bsd_zero.hpp"
786 #endif
787
788 public:
789 // debugging support (mostly used by debug.cpp but also fatal error handler)
790 static bool find(address pc, outputStream* st = tty); // OS specific function to make sense out of an address
791
792 static bool dont_yield(); // when true, JVM_Yield() is nop
793 static void print_statistics();
794
795 // Thread priority helpers (implemented in OS-specific part)
796 static OSReturn set_native_priority(Thread* thread, int native_prio);
797 static OSReturn get_native_priority(const Thread* const thread, int* priority_ptr);
798 static int java_to_os_priority[CriticalPriority + 1];
799 // Hint to the underlying OS that a task switch would not be good.
800 // Void return because it's a hint and can fail.
801 static void hint_no_preempt();
802
803 // Used at creation if requested by the diagnostic flag PauseAtStartup.
804 // Causes the VM to wait until an external stimulus has been applied
805 // (for Unix, that stimulus is a signal, for Windows, an external
806 // ResumeThread call)
807 static void pause();
808
809 class SuspendedThreadTaskContext {
810 public:
811 SuspendedThreadTaskContext(Thread* thread, void *ucontext) : _thread(thread), _ucontext(ucontext) {}
812 Thread* thread() const { return _thread; }
813 void* ucontext() const { return _ucontext; }
814 private:
815 Thread* _thread;
816 void* _ucontext;
817 };
818
819 class SuspendedThreadTask {
820 public:
821 SuspendedThreadTask(Thread* thread) : _thread(thread), _done(false) {}
822 virtual ~SuspendedThreadTask() {}
823 void run();
824 bool is_done() { return _done; }
825 virtual void do_task(const SuspendedThreadTaskContext& context) = 0;
826 protected:
827 private:
828 void internal_do_task();
829 Thread* _thread;
830 bool _done;
831 };
832
833 #ifndef TARGET_OS_FAMILY_windows
834 // Suspend/resume support
835 // Protocol:
836 //
837 // a thread starts in SR_RUNNING
838 //
839 // SR_RUNNING can go to
840 // * SR_SUSPEND_REQUEST when the WatcherThread wants to suspend it
841 // SR_SUSPEND_REQUEST can go to
842 // * SR_RUNNING if WatcherThread decides it waited for SR_SUSPENDED too long (timeout)
843 // * SR_SUSPENDED if the stopped thread receives the signal and switches state
844 // SR_SUSPENDED can go to
845 // * SR_WAKEUP_REQUEST when the WatcherThread has done the work and wants to resume
846 // SR_WAKEUP_REQUEST can go to
847 // * SR_RUNNING when the stopped thread receives the signal
848 // * SR_WAKEUP_REQUEST on timeout (resend the signal and try again)
849 class SuspendResume {
850 public:
851 enum State {
852 SR_RUNNING,
853 SR_SUSPEND_REQUEST,
854 SR_SUSPENDED,
855 SR_WAKEUP_REQUEST
856 };
857
858 private:
859 volatile State _state;
860
861 private:
862 /* try to switch state from state "from" to state "to"
863 * returns the state set after the method is complete
864 */
865 State switch_state(State from, State to);
866
867 public:
868 SuspendResume() : _state(SR_RUNNING) { }
869
870 State state() const { return _state; }
871
872 State request_suspend() {
873 return switch_state(SR_RUNNING, SR_SUSPEND_REQUEST);
874 }
875
876 State cancel_suspend() {
877 return switch_state(SR_SUSPEND_REQUEST, SR_RUNNING);
878 }
879
880 State suspended() {
881 return switch_state(SR_SUSPEND_REQUEST, SR_SUSPENDED);
882 }
883
884 State request_wakeup() {
885 return switch_state(SR_SUSPENDED, SR_WAKEUP_REQUEST);
886 }
887
888 State running() {
889 return switch_state(SR_WAKEUP_REQUEST, SR_RUNNING);
890 }
891
892 bool is_running() const {
893 return _state == SR_RUNNING;
894 }
895
896 bool is_suspend_request() const {
897 return _state == SR_SUSPEND_REQUEST;
898 }
899
900 bool is_suspended() const {
901 return _state == SR_SUSPENDED;
902 }
903 };
904 #endif
905
906
907 protected:
908 static long _rand_seed; // seed for random number generator
909 static int _processor_count; // number of processors
910
911 static char* format_boot_path(const char* format_string,
912 const char* home,
913 int home_len,
914 char fileSep,
915 char pathSep);
916 static bool set_boot_path(char fileSep, char pathSep);
917 static char** split_path(const char* path, int* n);
918
919 };
920
921 // Note that "PAUSE" is almost always used with synchronization
922 // so arguably we should provide Atomic::SpinPause() instead
923 // of the global SpinPause() with C linkage.
924 // It'd also be eligible for inlining on many platforms.
925
926 extern "C" int SpinPause();
927
928 #endif // SHARE_VM_RUNTIME_OS_HPP