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 void init_ergo(void); // Called after command line parsing
141 // before VM ergonomics processing.
142 static jint init_2(void); // Called after command line parsing
143 // and VM ergonomics processing
144 static void init_globals(void) { // Called from init_globals() in init.cpp
145 init_globals_ext();
146 }
147 static void init_3(void); // Called at the end of vm init
148
149 // File names are case-insensitive on windows only
150 // Override me as needed
151 static int file_name_strcmp(const char* s1, const char* s2);
152
153 static bool getenv(const char* name, char* buffer, int len);
154 static bool have_special_privileges();
155
156 static jlong javaTimeMillis();
157 static jlong javaTimeNanos();
158 static void javaTimeNanos_info(jvmtiTimerInfo *info_ptr);
159 static void run_periodic_checks();
160
161
162 // Returns the elapsed time in seconds since the vm started.
163 static double elapsedTime();
164
165 // Returns real time in seconds since an arbitrary point
166 // in the past.
167 static bool getTimesSecs(double* process_real_time,
168 double* process_user_time,
169 double* process_system_time);
170
171 // Interface to the performance counter
172 static jlong elapsed_counter();
173 static jlong elapsed_frequency();
174
175 // The "virtual time" of a thread is the amount of time a thread has
176 // actually run. The first function indicates whether the OS supports
177 // this functionality for the current thread, and if so:
178 // * the second enables vtime tracking (if that is required).
179 // * the third tells whether vtime is enabled.
180 // * the fourth returns the elapsed virtual time for the current
181 // thread.
182 static bool supports_vtime();
183 static bool enable_vtime();
184 static bool vtime_enabled();
185 static double elapsedVTime();
186
187 // Return current local time in a string (YYYY-MM-DD HH:MM:SS).
188 // It is MT safe, but not async-safe, as reading time zone
189 // information may require a lock on some platforms.
190 static char* local_time_string(char *buf, size_t buflen);
191 static struct tm* localtime_pd (const time_t* clock, struct tm* res);
192 // Fill in buffer with current local time as an ISO-8601 string.
193 // E.g., YYYY-MM-DDThh:mm:ss.mmm+zzzz.
194 // Returns buffer, or NULL if it failed.
195 static char* iso8601_time(char* buffer, size_t buffer_length);
196
197 // Interface for detecting multiprocessor system
198 static inline bool is_MP() {
199 assert(_processor_count > 0, "invalid processor count");
200 return _processor_count > 1 || AssumeMP;
201 }
202 static julong available_memory();
203 static julong physical_memory();
204 static bool has_allocatable_memory_limit(julong* limit);
205 static bool is_server_class_machine();
206
207 // number of CPUs
208 static int processor_count() {
209 return _processor_count;
210 }
211 static void set_processor_count(int count) { _processor_count = count; }
212
213 // Returns the number of CPUs this process is currently allowed to run on.
214 // Note that on some OSes this can change dynamically.
215 static int active_processor_count();
216
217 // Bind processes to processors.
218 // This is a two step procedure:
219 // first you generate a distribution of processes to processors,
220 // then you bind processes according to that distribution.
221 // Compute a distribution for number of processes to processors.
222 // Stores the processor id's into the distribution array argument.
223 // Returns true if it worked, false if it didn't.
224 static bool distribute_processes(uint length, uint* distribution);
225 // Binds the current process to a processor.
226 // Returns true if it worked, false if it didn't.
227 static bool bind_to_processor(uint processor_id);
228
229 // Give a name to the current thread.
230 static void set_native_thread_name(const char *name);
231
232 // Interface for stack banging (predetect possible stack overflow for
233 // exception processing) There are guard pages, and above that shadow
234 // pages for stack overflow checking.
235 static bool uses_stack_guard_pages();
236 static bool allocate_stack_guard_pages();
237 static void bang_stack_shadow_pages();
238 static bool stack_shadow_pages_available(Thread *thread, methodHandle method);
239
240 // OS interface to Virtual Memory
241
242 // Return the default page size.
243 static int vm_page_size();
244
245 // Return the page size to use for a region of memory. The min_pages argument
246 // is a hint intended to limit fragmentation; it says the returned page size
247 // should be <= region_max_size / min_pages. Because min_pages is a hint,
248 // this routine may return a size larger than region_max_size / min_pages.
249 //
250 // The current implementation ignores min_pages if a larger page size is an
251 // exact multiple of both region_min_size and region_max_size. This allows
252 // larger pages to be used when doing so would not cause fragmentation; in
253 // particular, a single page can be used when region_min_size ==
254 // region_max_size == a supported page size.
255 static size_t page_size_for_region(size_t region_min_size,
256 size_t region_max_size,
257 uint min_pages);
258 // return the largest page size that can be used
259 static size_t max_page_size() {
260 // the _page_sizes array is sorted in descending order.
261 return _page_sizes[0];
262 }
263
264 // Methods for tracing page sizes returned by the above method; enabled by
265 // TracePageSizes. The region_{min,max}_size parameters should be the values
266 // passed to page_size_for_region() and page_size should be the result of that
267 // call. The (optional) base and size parameters should come from the
268 // ReservedSpace base() and size() methods.
269 static void trace_page_sizes(const char* str, const size_t* page_sizes,
270 int count) PRODUCT_RETURN;
271 static void trace_page_sizes(const char* str, const size_t region_min_size,
272 const size_t region_max_size,
273 const size_t page_size,
274 const char* base = NULL,
275 const size_t size = 0) PRODUCT_RETURN;
276
277 static int vm_allocation_granularity();
278 static char* reserve_memory(size_t bytes, char* addr = 0,
279 size_t alignment_hint = 0);
280 static char* reserve_memory(size_t bytes, char* addr,
281 size_t alignment_hint, MEMFLAGS flags);
282 static char* reserve_memory_aligned(size_t size, size_t alignment);
283 static char* attempt_reserve_memory_at(size_t bytes, char* addr);
284 static void split_reserved_memory(char *base, size_t size,
285 size_t split, bool realloc);
286 static bool commit_memory(char* addr, size_t bytes, bool executable);
287 static bool commit_memory(char* addr, size_t size, size_t alignment_hint,
288 bool executable);
289 // Same as commit_memory() that either succeeds or calls
290 // vm_exit_out_of_memory() with the specified mesg.
291 static void commit_memory_or_exit(char* addr, size_t bytes,
292 bool executable, const char* mesg);
293 static void commit_memory_or_exit(char* addr, size_t size,
294 size_t alignment_hint,
295 bool executable, const char* mesg);
296 static bool uncommit_memory(char* addr, size_t bytes);
297 static bool release_memory(char* addr, size_t bytes);
298
299 enum ProtType { MEM_PROT_NONE, MEM_PROT_READ, MEM_PROT_RW, MEM_PROT_RWX };
300 static bool protect_memory(char* addr, size_t bytes, ProtType prot,
301 bool is_committed = true);
302
303 static bool guard_memory(char* addr, size_t bytes);
304 static bool unguard_memory(char* addr, size_t bytes);
305 static bool create_stack_guard_pages(char* addr, size_t bytes);
306 static bool pd_create_stack_guard_pages(char* addr, size_t bytes);
307 static bool remove_stack_guard_pages(char* addr, size_t bytes);
308
309 static char* map_memory(int fd, const char* file_name, size_t file_offset,
310 char *addr, size_t bytes, bool read_only = false,
311 bool allow_exec = false);
312 static char* remap_memory(int fd, const char* file_name, size_t file_offset,
313 char *addr, size_t bytes, bool read_only,
314 bool allow_exec);
315 static bool unmap_memory(char *addr, size_t bytes);
316 static void free_memory(char *addr, size_t bytes, size_t alignment_hint);
317 static void realign_memory(char *addr, size_t bytes, size_t alignment_hint);
318
319 // NUMA-specific interface
320 static bool numa_has_static_binding();
321 static bool numa_has_group_homing();
322 static void numa_make_local(char *addr, size_t bytes, int lgrp_hint);
323 static void numa_make_global(char *addr, size_t bytes);
324 static size_t numa_get_groups_num();
325 static size_t numa_get_leaf_groups(int *ids, size_t size);
326 static bool numa_topology_changed();
327 static int numa_get_group_id();
328
329 // Page manipulation
330 struct page_info {
331 size_t size;
332 int lgrp_id;
333 };
334 static bool get_page_info(char *start, page_info* info);
335 static char* scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found);
336
337 static char* non_memory_address_word();
338 // reserve, commit and pin the entire memory region
339 static char* reserve_memory_special(size_t size, size_t alignment,
340 char* addr, bool executable);
341 static bool release_memory_special(char* addr, size_t bytes);
342 static void large_page_init();
343 static size_t large_page_size();
344 static bool can_commit_large_page_memory();
345 static bool can_execute_large_page_memory();
346
347 // OS interface to polling page
348 static address get_polling_page() { return _polling_page; }
349 static void set_polling_page(address page) { _polling_page = page; }
350 static bool is_poll_address(address addr) { return addr >= _polling_page && addr < (_polling_page + os::vm_page_size()); }
351 static void make_polling_page_unreadable();
352 static void make_polling_page_readable();
353
354 // Routines used to serialize the thread state without using membars
355 static void serialize_thread_states();
356
357 // Since we write to the serialize page from every thread, we
358 // want stores to be on unique cache lines whenever possible
359 // in order to minimize CPU cross talk. We pre-compute the
360 // amount to shift the thread* to make this offset unique to
361 // each thread.
362 static int get_serialize_page_shift_count() {
363 return SerializePageShiftCount;
364 }
365
366 static void set_serialize_page_mask(uintptr_t mask) {
367 _serialize_page_mask = mask;
368 }
369
370 static unsigned int get_serialize_page_mask() {
371 return _serialize_page_mask;
372 }
373
374 static void set_memory_serialize_page(address page);
375
376 static address get_memory_serialize_page() {
377 return (address)_mem_serialize_page;
378 }
379
380 static inline void write_memory_serialize_page(JavaThread *thread) {
381 uintptr_t page_offset = ((uintptr_t)thread >>
382 get_serialize_page_shift_count()) &
383 get_serialize_page_mask();
384 *(volatile int32_t *)((uintptr_t)_mem_serialize_page+page_offset) = 1;
385 }
386
387 static bool is_memory_serialize_page(JavaThread *thread, address addr) {
388 if (UseMembar) return false;
389 // Previously this function calculated the exact address of this
390 // thread's serialize page, and checked if the faulting address
391 // was equal. However, some platforms mask off faulting addresses
392 // to the page size, so now we just check that the address is
393 // within the page. This makes the thread argument unnecessary,
394 // but we retain the NULL check to preserve existing behaviour.
395 if (thread == NULL) return false;
396 address page = (address) _mem_serialize_page;
397 return addr >= page && addr < (page + os::vm_page_size());
398 }
399
400 static void block_on_serialize_page_trap();
401
402 // threads
403
404 enum ThreadType {
405 vm_thread,
406 cgc_thread, // Concurrent GC thread
407 pgc_thread, // Parallel GC thread
408 java_thread,
409 compiler_thread,
410 watcher_thread,
411 os_thread
412 };
413
414 static bool create_thread(Thread* thread,
415 ThreadType thr_type,
416 size_t stack_size = 0);
417 static bool create_main_thread(JavaThread* thread);
418 static bool create_attached_thread(JavaThread* thread);
419 static void pd_start_thread(Thread* thread);
420 static void start_thread(Thread* thread);
421
422 static void initialize_thread(Thread* thr);
423 static void free_thread(OSThread* osthread);
424
425 // thread id on Linux/64bit is 64bit, on Windows and Solaris, it's 32bit
426 static intx current_thread_id();
427 static int current_process_id();
428 static int sleep(Thread* thread, jlong ms, bool interruptable);
429 static int naked_sleep();
430 static void infinite_sleep(); // never returns, use with CAUTION
431 static void yield(); // Yields to all threads with same priority
432 enum YieldResult {
433 YIELD_SWITCHED = 1, // caller descheduled, other ready threads exist & ran
434 YIELD_NONEREADY = 0, // No other runnable/ready threads.
435 // platform-specific yield return immediately
436 YIELD_UNKNOWN = -1 // Unknown: platform doesn't support _SWITCHED or _NONEREADY
437 // YIELD_SWITCHED and YIELD_NONREADY imply the platform supports a "strong"
438 // yield that can be used in lieu of blocking.
439 } ;
440 static YieldResult NakedYield () ;
441 static void yield_all(int attempts = 0); // Yields to all other threads including lower priority
442 static void loop_breaker(int attempts); // called from within tight loops to possibly influence time-sharing
443 static OSReturn set_priority(Thread* thread, ThreadPriority priority);
444 static OSReturn get_priority(const Thread* const thread, ThreadPriority& priority);
445
446 static void interrupt(Thread* thread);
447 static bool is_interrupted(Thread* thread, bool clear_interrupted);
448
449 static int pd_self_suspend_thread(Thread* thread);
450
451 static ExtendedPC fetch_frame_from_context(void* ucVoid, intptr_t** sp, intptr_t** fp);
452 static frame fetch_frame_from_context(void* ucVoid);
453
454 static ExtendedPC get_thread_pc(Thread *thread);
455 static void breakpoint();
456
457 static address current_stack_pointer();
458 static address current_stack_base();
459 static size_t current_stack_size();
460
461 static void verify_stack_alignment() PRODUCT_RETURN;
462
463 static int message_box(const char* title, const char* message);
464 static char* do_you_want_to_debug(const char* message);
465
466 // run cmd in a separate process and return its exit code; or -1 on failures
467 static int fork_and_exec(char *cmd);
468
469 // Set file to send error reports.
470 static void set_error_file(const char *logfile);
471
472 // os::exit() is merged with vm_exit()
473 // static void exit(int num);
474
475 // Terminate the VM, but don't exit the process
476 static void shutdown();
477
478 // Terminate with an error. Default is to generate a core file on platforms
479 // that support such things. This calls shutdown() and then aborts.
480 static void abort(bool dump_core = true);
481
482 // Die immediately, no exit hook, no abort hook, no cleanup.
483 static void die();
484
485 // File i/o operations
486 static const int default_file_open_flags();
487 static int open(const char *path, int oflag, int mode);
488 static FILE* open(int fd, const char* mode);
489 static int close(int fd);
490 static jlong lseek(int fd, jlong offset, int whence);
491 static char* native_path(char *path);
492 static int ftruncate(int fd, jlong length);
493 static int fsync(int fd);
494 static int available(int fd, jlong *bytes);
495
496 //File i/o operations
497
498 static size_t read(int fd, void *buf, unsigned int nBytes);
499 static size_t restartable_read(int fd, void *buf, unsigned int nBytes);
500 static size_t write(int fd, const void *buf, unsigned int nBytes);
501
502 // Reading directories.
503 static DIR* opendir(const char* dirname);
504 static int readdir_buf_size(const char *path);
505 static struct dirent* readdir(DIR* dirp, dirent* dbuf);
506 static int closedir(DIR* dirp);
507
508 // Dynamic library extension
509 static const char* dll_file_extension();
510
511 static const char* get_temp_directory();
512 static const char* get_current_directory(char *buf, size_t buflen);
513
514 // Builds a platform-specific full library path given a ld path and lib name
515 // Returns true if buffer contains full path to existing file, false otherwise
516 static bool dll_build_name(char* buffer, size_t size,
517 const char* pathname, const char* fname);
518
519 // Symbol lookup, find nearest function name; basically it implements
520 // dladdr() for all platforms. Name of the nearest function is copied
521 // to buf. Distance from its base address is optionally returned as offset.
522 // If function name is not found, buf[0] is set to '\0' and offset is
523 // set to -1 (if offset is non-NULL).
524 static bool dll_address_to_function_name(address addr, char* buf,
525 int buflen, int* offset);
526
527 // Locate DLL/DSO. On success, full path of the library is copied to
528 // buf, and offset is optionally set to be the distance between addr
529 // and the library's base address. On failure, buf[0] is set to '\0'
530 // and offset is set to -1 (if offset is non-NULL).
531 static bool dll_address_to_library_name(address addr, char* buf,
532 int buflen, int* offset);
533
534 // Find out whether the pc is in the static code for jvm.dll/libjvm.so.
535 static bool address_is_in_vm(address addr);
536
537 // Loads .dll/.so and
538 // in case of error it checks if .dll/.so was built for the
539 // same architecture as Hotspot is running on
540 static void* dll_load(const char *name, char *ebuf, int ebuflen);
541
542 // lookup symbol in a shared library
543 static void* dll_lookup(void* handle, const char* name);
544
545 // Unload library
546 static void dll_unload(void *lib);
547
548 // Print out system information; they are called by fatal error handler.
549 // Output format may be different on different platforms.
550 static void print_os_info(outputStream* st);
551 static void print_os_info_brief(outputStream* st);
552 static void print_cpu_info(outputStream* st);
553 static void pd_print_cpu_info(outputStream* st);
554 static void print_memory_info(outputStream* st);
555 static void print_dll_info(outputStream* st);
556 static void print_environment_variables(outputStream* st, const char** env_list, char* buffer, int len);
557 static void print_context(outputStream* st, void* context);
558 static void print_register_info(outputStream* st, void* context);
559 static void print_siginfo(outputStream* st, void* siginfo);
560 static void print_signal_handlers(outputStream* st, char* buf, size_t buflen);
561 static void print_date_and_time(outputStream* st);
562
563 static void print_location(outputStream* st, intptr_t x, bool verbose = false);
564 static size_t lasterror(char *buf, size_t len);
565 static int get_last_error();
566
567 // Determines whether the calling process is being debugged by a user-mode debugger.
568 static bool is_debugger_attached();
569
570 // wait for a key press if PauseAtExit is set
571 static void wait_for_keypress_at_exit(void);
572
573 // The following two functions are used by fatal error handler to trace
574 // native (C) frames. They are not part of frame.hpp/frame.cpp because
575 // frame.hpp/cpp assume thread is JavaThread, and also because different
576 // OS/compiler may have different convention or provide different API to
577 // walk C frames.
578 //
579 // We don't attempt to become a debugger, so we only follow frames if that
580 // does not require a lookup in the unwind table, which is part of the binary
581 // file but may be unsafe to read after a fatal error. So on x86, we can
582 // only walk stack if %ebp is used as frame pointer; on ia64, it's not
583 // possible to walk C stack without having the unwind table.
584 static bool is_first_C_frame(frame *fr);
585 static frame get_sender_for_C_frame(frame *fr);
586
587 // return current frame. pc() and sp() are set to NULL on failure.
588 static frame current_frame();
589
590 static void print_hex_dump(outputStream* st, address start, address end, int unitsize);
591
592 // returns a string to describe the exception/signal;
593 // returns NULL if exception_code is not an OS exception/signal.
594 static const char* exception_name(int exception_code, char* buf, size_t buflen);
595
596 // Returns native Java library, loads if necessary
597 static void* native_java_library();
598
599 // Fills in path to jvm.dll/libjvm.so (used by the Disassembler)
600 static void jvm_path(char *buf, jint buflen);
601
602 // Returns true if we are running in a headless jre.
603 static bool is_headless_jre();
604
605 // JNI names
606 static void print_jni_name_prefix_on(outputStream* st, int args_size);
607 static void print_jni_name_suffix_on(outputStream* st, int args_size);
608
609 // File conventions
610 static const char* file_separator();
611 static const char* line_separator();
612 static const char* path_separator();
613
614 // Init os specific system properties values
615 static void init_system_properties_values();
616
617 // IO operations, non-JVM_ version.
618 static int stat(const char* path, struct stat* sbuf);
619 static bool dir_is_empty(const char* path);
620
621 // IO operations on binary files
622 static int create_binary_file(const char* path, bool rewrite_existing);
623 static jlong current_file_offset(int fd);
624 static jlong seek_to_file_offset(int fd, jlong offset);
625
626 // Thread Local Storage
627 static int allocate_thread_local_storage();
628 static void thread_local_storage_at_put(int index, void* value);
629 static void* thread_local_storage_at(int index);
630 static void free_thread_local_storage(int index);
631
632 // Stack walk
633 static address get_caller_pc(int n = 0);
634
635 // General allocation (must be MT-safe)
636 static void* malloc (size_t size, MEMFLAGS flags, address caller_pc = 0);
637 static void* realloc (void *memblock, size_t size, MEMFLAGS flags, address caller_pc = 0);
638 static void free (void *memblock, MEMFLAGS flags = mtNone);
639 static bool check_heap(bool force = false); // verify C heap integrity
640 static char* strdup(const char *, MEMFLAGS flags = mtInternal); // Like strdup
641
642 #ifndef PRODUCT
643 static julong num_mallocs; // # of calls to malloc/realloc
644 static julong alloc_bytes; // # of bytes allocated
645 static julong num_frees; // # of calls to free
646 static julong free_bytes; // # of bytes freed
647 #endif
648
649 // SocketInterface (ex HPI SocketInterface )
650 static int socket(int domain, int type, int protocol);
651 static int socket_close(int fd);
652 static int socket_shutdown(int fd, int howto);
653 static int recv(int fd, char* buf, size_t nBytes, uint flags);
654 static int send(int fd, char* buf, size_t nBytes, uint flags);
655 static int raw_send(int fd, char* buf, size_t nBytes, uint flags);
656 static int timeout(int fd, long timeout);
657 static int listen(int fd, int count);
658 static int connect(int fd, struct sockaddr* him, socklen_t len);
659 static int bind(int fd, struct sockaddr* him, socklen_t len);
660 static int accept(int fd, struct sockaddr* him, socklen_t* len);
661 static int recvfrom(int fd, char* buf, size_t nbytes, uint flags,
662 struct sockaddr* from, socklen_t* fromlen);
663 static int get_sock_name(int fd, struct sockaddr* him, socklen_t* len);
664 static int sendto(int fd, char* buf, size_t len, uint flags,
665 struct sockaddr* to, socklen_t tolen);
666 static int socket_available(int fd, jint* pbytes);
667
668 static int get_sock_opt(int fd, int level, int optname,
669 char* optval, socklen_t* optlen);
670 static int set_sock_opt(int fd, int level, int optname,
671 const char* optval, socklen_t optlen);
672 static int get_host_name(char* name, int namelen);
673
674 static struct hostent* get_host_by_name(char* name);
675
676 // Support for signals (see JVM_RaiseSignal, JVM_RegisterSignal)
677 static void signal_init();
678 static void signal_init_pd();
679 static void signal_notify(int signal_number);
680 static void* signal(int signal_number, void* handler);
681 static void signal_raise(int signal_number);
682 static int signal_wait();
683 static int signal_lookup();
684 static void* user_handler();
685 static void terminate_signal_thread();
686 static int sigexitnum_pd();
687
688 // random number generation
689 static long random(); // return 32bit pseudorandom number
690 static void init_random(long initval); // initialize random sequence
691
692 // Structured OS Exception support
693 static void os_exception_wrapper(java_call_t f, JavaValue* value, methodHandle* method, JavaCallArguments* args, Thread* thread);
694
695 // On Windows this will create an actual minidump, on Linux/Solaris it will simply check core dump limits
696 static void check_or_create_dump(void* exceptionRecord, void* contextRecord, char* buffer, size_t bufferSize);
697
698 // Get the default path to the core file
699 // Returns the length of the string
700 static int get_core_path(char* buffer, size_t bufferSize);
701
702 // JVMTI & JVM monitoring and management support
703 // The thread_cpu_time() and current_thread_cpu_time() are only
704 // supported if is_thread_cpu_time_supported() returns true.
705 // They are not supported on Solaris T1.
706
707 // Thread CPU Time - return the fast estimate on a platform
708 // On Solaris - call gethrvtime (fast) - user time only
709 // On Linux - fast clock_gettime where available - user+sys
710 // - otherwise: very slow /proc fs - user+sys
711 // On Windows - GetThreadTimes - user+sys
712 static jlong current_thread_cpu_time();
713 static jlong thread_cpu_time(Thread* t);
714
715 // Thread CPU Time with user_sys_cpu_time parameter.
716 //
717 // If user_sys_cpu_time is true, user+sys time is returned.
718 // Otherwise, only user time is returned
719 static jlong current_thread_cpu_time(bool user_sys_cpu_time);
720 static jlong thread_cpu_time(Thread* t, bool user_sys_cpu_time);
721
722 // Return a bunch of info about the timers.
723 // Note that the returned info for these two functions may be different
724 // on some platforms
725 static void current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr);
726 static void thread_cpu_time_info(jvmtiTimerInfo *info_ptr);
727
728 static bool is_thread_cpu_time_supported();
729
730 // System loadavg support. Returns -1 if load average cannot be obtained.
731 static int loadavg(double loadavg[], int nelem);
732
733 // Hook for os specific jvm options that we don't want to abort on seeing
734 static bool obsolete_option(const JavaVMOption *option);
735
736 // Read file line by line. If line is longer than bsize,
737 // rest of line is skipped. Returns number of bytes read or -1 on EOF
738 static int get_line_chars(int fd, char *buf, const size_t bsize);
739
740 // Extensions
741 #include "runtime/os_ext.hpp"
742
743 public:
744 class CrashProtectionCallback : public StackObj {
745 public:
746 virtual void call() = 0;
747 };
748
749 // Platform dependent stuff
750 #ifdef TARGET_OS_FAMILY_linux
751 # include "os_linux.hpp"
752 # include "os_posix.hpp"
753 #endif
754 #ifdef TARGET_OS_FAMILY_solaris
755 # include "os_solaris.hpp"
756 # include "os_posix.hpp"
757 #endif
758 #ifdef TARGET_OS_FAMILY_windows
759 # include "os_windows.hpp"
760 #endif
761 #ifdef TARGET_OS_FAMILY_bsd
762 # include "os_posix.hpp"
763 # include "os_bsd.hpp"
764 #endif
765 #ifdef TARGET_OS_ARCH_linux_x86
766 # include "os_linux_x86.hpp"
767 #endif
768 #ifdef TARGET_OS_ARCH_linux_sparc
769 # include "os_linux_sparc.hpp"
770 #endif
771 #ifdef TARGET_OS_ARCH_linux_zero
772 # include "os_linux_zero.hpp"
773 #endif
774 #ifdef TARGET_OS_ARCH_solaris_x86
775 # include "os_solaris_x86.hpp"
776 #endif
777 #ifdef TARGET_OS_ARCH_solaris_sparc
778 # include "os_solaris_sparc.hpp"
779 #endif
780 #ifdef TARGET_OS_ARCH_windows_x86
781 # include "os_windows_x86.hpp"
782 #endif
783 #ifdef TARGET_OS_ARCH_linux_arm
784 # include "os_linux_arm.hpp"
785 #endif
786 #ifdef TARGET_OS_ARCH_linux_ppc
787 # include "os_linux_ppc.hpp"
788 #endif
789 #ifdef TARGET_OS_ARCH_bsd_x86
790 # include "os_bsd_x86.hpp"
791 #endif
792 #ifdef TARGET_OS_ARCH_bsd_zero
793 # include "os_bsd_zero.hpp"
794 #endif
795
796 public:
797 // debugging support (mostly used by debug.cpp but also fatal error handler)
798 static bool find(address pc, outputStream* st = tty); // OS specific function to make sense out of an address
799
800 static bool dont_yield(); // when true, JVM_Yield() is nop
801 static void print_statistics();
802
803 // Thread priority helpers (implemented in OS-specific part)
804 static OSReturn set_native_priority(Thread* thread, int native_prio);
805 static OSReturn get_native_priority(const Thread* const thread, int* priority_ptr);
806 static int java_to_os_priority[CriticalPriority + 1];
807 // Hint to the underlying OS that a task switch would not be good.
808 // Void return because it's a hint and can fail.
809 static void hint_no_preempt();
810
811 // Used at creation if requested by the diagnostic flag PauseAtStartup.
812 // Causes the VM to wait until an external stimulus has been applied
813 // (for Unix, that stimulus is a signal, for Windows, an external
814 // ResumeThread call)
815 static void pause();
816
817 class SuspendedThreadTaskContext {
818 public:
819 SuspendedThreadTaskContext(Thread* thread, void *ucontext) : _thread(thread), _ucontext(ucontext) {}
820 Thread* thread() const { return _thread; }
821 void* ucontext() const { return _ucontext; }
822 private:
823 Thread* _thread;
824 void* _ucontext;
825 };
826
827 class SuspendedThreadTask {
828 public:
829 SuspendedThreadTask(Thread* thread) : _thread(thread), _done(false) {}
830 virtual ~SuspendedThreadTask() {}
831 void run();
832 bool is_done() { return _done; }
833 virtual void do_task(const SuspendedThreadTaskContext& context) = 0;
834 protected:
835 private:
836 void internal_do_task();
837 Thread* _thread;
838 bool _done;
839 };
840
841 #ifndef TARGET_OS_FAMILY_windows
842 // Suspend/resume support
843 // Protocol:
844 //
845 // a thread starts in SR_RUNNING
846 //
847 // SR_RUNNING can go to
848 // * SR_SUSPEND_REQUEST when the WatcherThread wants to suspend it
849 // SR_SUSPEND_REQUEST can go to
850 // * SR_RUNNING if WatcherThread decides it waited for SR_SUSPENDED too long (timeout)
851 // * SR_SUSPENDED if the stopped thread receives the signal and switches state
852 // SR_SUSPENDED can go to
853 // * SR_WAKEUP_REQUEST when the WatcherThread has done the work and wants to resume
854 // SR_WAKEUP_REQUEST can go to
855 // * SR_RUNNING when the stopped thread receives the signal
856 // * SR_WAKEUP_REQUEST on timeout (resend the signal and try again)
857 class SuspendResume {
858 public:
859 enum State {
860 SR_RUNNING,
861 SR_SUSPEND_REQUEST,
862 SR_SUSPENDED,
863 SR_WAKEUP_REQUEST
864 };
865
866 private:
867 volatile State _state;
868
869 private:
870 /* try to switch state from state "from" to state "to"
871 * returns the state set after the method is complete
872 */
873 State switch_state(State from, State to);
874
875 public:
876 SuspendResume() : _state(SR_RUNNING) { }
877
878 State state() const { return _state; }
879
880 State request_suspend() {
881 return switch_state(SR_RUNNING, SR_SUSPEND_REQUEST);
882 }
883
884 State cancel_suspend() {
885 return switch_state(SR_SUSPEND_REQUEST, SR_RUNNING);
886 }
887
888 State suspended() {
889 return switch_state(SR_SUSPEND_REQUEST, SR_SUSPENDED);
890 }
891
892 State request_wakeup() {
893 return switch_state(SR_SUSPENDED, SR_WAKEUP_REQUEST);
894 }
895
896 State running() {
897 return switch_state(SR_WAKEUP_REQUEST, SR_RUNNING);
898 }
899
900 bool is_running() const {
901 return _state == SR_RUNNING;
902 }
903
904 bool is_suspend_request() const {
905 return _state == SR_SUSPEND_REQUEST;
906 }
907
908 bool is_suspended() const {
909 return _state == SR_SUSPENDED;
910 }
911 };
912 #endif
913
914
915 protected:
916 static long _rand_seed; // seed for random number generator
917 static int _processor_count; // number of processors
918
919 static char* format_boot_path(const char* format_string,
920 const char* home,
921 int home_len,
922 char fileSep,
923 char pathSep);
924 static bool set_boot_path(char fileSep, char pathSep);
925 static char** split_path(const char* path, int* n);
926
927 };
928
929 // Note that "PAUSE" is almost always used with synchronization
930 // so arguably we should provide Atomic::SpinPause() instead
931 // of the global SpinPause() with C linkage.
932 // It'd also be eligible for inlining on many platforms.
933
934 extern "C" int SpinPause();
935
936 #endif // SHARE_VM_RUNTIME_OS_HPP