1 /*
2 * Copyright (c) 1997, 2014, 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_aix
45 # include "jvm_aix.h"
46 # include <setjmp.h>
47 #endif
48 #ifdef TARGET_OS_FAMILY_bsd
49 # include "jvm_bsd.h"
50 # include <setjmp.h>
51 # ifdef __APPLE__
52 # include <mach/mach_time.h>
53 # endif
54 #endif
55
56 class AgentLibrary;
57
58 // os defines the interface to operating system; this includes traditional
59 // OS services (time, I/O) as well as other functionality with system-
60 // dependent code.
61
62 typedef void (*dll_func)(...);
63
64 class Thread;
65 class JavaThread;
66 class Event;
67 class DLL;
68 class FileHandle;
69 class NativeCallStack;
70
71 template<class E> class GrowableArray;
72
73 // %%%%% Moved ThreadState, START_FN, OSThread to new osThread.hpp. -- Rose
74
75 // Platform-independent error return values from OS functions
76 enum OSReturn {
77 OS_OK = 0, // Operation was successful
78 OS_ERR = -1, // Operation failed
79 OS_INTRPT = -2, // Operation was interrupted
80 OS_TIMEOUT = -3, // Operation timed out
81 OS_NOMEM = -5, // Operation failed for lack of memory
82 OS_NORESOURCE = -6 // Operation failed for lack of nonmemory resource
83 };
84
85 enum ThreadPriority { // JLS 20.20.1-3
86 NoPriority = -1, // Initial non-priority value
87 MinPriority = 1, // Minimum priority
88 NormPriority = 5, // Normal (non-daemon) priority
89 NearMaxPriority = 9, // High priority, used for VMThread
90 MaxPriority = 10, // Highest priority, used for WatcherThread
91 // ensures that VMThread doesn't starve profiler
92 CriticalPriority = 11 // Critical thread priority
93 };
94
95 // Executable parameter flag for os::commit_memory() and
96 // os::commit_memory_or_exit().
97 const bool ExecMem = true;
98
99 // Typedef for structured exception handling support
100 typedef void (*java_call_t)(JavaValue* value, methodHandle* method, JavaCallArguments* args, Thread* thread);
101
102 class MallocTracker;
103
104 class os: AllStatic {
105 friend class VMStructs;
106 friend class MallocTracker;
107 public:
108 enum { page_sizes_max = 9 }; // Size of _page_sizes array (8 plus a sentinel)
109
110 private:
111 static OSThread* _starting_thread;
112 static address _polling_page;
113 static volatile int32_t * _mem_serialize_page;
114 static uintptr_t _serialize_page_mask;
115 public:
116 static size_t _page_sizes[page_sizes_max];
117
118 private:
119 static void init_page_sizes(size_t default_page_size) {
120 _page_sizes[0] = default_page_size;
121 _page_sizes[1] = 0; // sentinel
122 }
123
124 static char* pd_reserve_memory(size_t bytes, char* addr = 0,
125 size_t alignment_hint = 0);
126 static char* pd_attempt_reserve_memory_at(size_t bytes, char* addr);
127 static void pd_split_reserved_memory(char *base, size_t size,
128 size_t split, bool realloc);
129 static bool pd_commit_memory(char* addr, size_t bytes, bool executable);
130 static bool pd_commit_memory(char* addr, size_t size, size_t alignment_hint,
131 bool executable);
132 // Same as pd_commit_memory() that either succeeds or calls
133 // vm_exit_out_of_memory() with the specified mesg.
134 static void pd_commit_memory_or_exit(char* addr, size_t bytes,
135 bool executable, const char* mesg);
136 static void pd_commit_memory_or_exit(char* addr, size_t size,
137 size_t alignment_hint,
138 bool executable, const char* mesg);
139 static bool pd_uncommit_memory(char* addr, size_t bytes);
140 static bool pd_release_memory(char* addr, size_t bytes);
141
142 static char* pd_map_memory(int fd, const char* file_name, size_t file_offset,
143 char *addr, size_t bytes, bool read_only = false,
144 bool allow_exec = false);
145 static char* pd_remap_memory(int fd, const char* file_name, size_t file_offset,
146 char *addr, size_t bytes, bool read_only,
147 bool allow_exec);
148 static bool pd_unmap_memory(char *addr, size_t bytes);
149 static void pd_free_memory(char *addr, size_t bytes, size_t alignment_hint);
150 static void pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint);
151
152
153 public:
154 static void init(void); // Called before command line parsing
155 static void init_before_ergo(void); // Called after command line parsing
156 // before VM ergonomics processing.
157 static jint init_2(void); // Called after command line parsing
158 // and VM ergonomics processing
159 static void init_globals(void) { // Called from init_globals() in init.cpp
160 init_globals_ext();
161 }
162
163 // File names are case-insensitive on windows only
164 // Override me as needed
165 static int file_name_strcmp(const char* s1, const char* s2);
166
167 // get/unset environment variable
168 static bool getenv(const char* name, char* buffer, int len);
169 static bool unsetenv(const char* name);
170
171 static bool have_special_privileges();
172
173 static jlong javaTimeMillis();
174 static jlong javaTimeNanos();
175 static void javaTimeNanos_info(jvmtiTimerInfo *info_ptr);
176 static void run_periodic_checks();
177
178
179 // Returns the elapsed time in seconds since the vm started.
180 static double elapsedTime();
181
182 // Returns real time in seconds since an arbitrary point
183 // in the past.
184 static bool getTimesSecs(double* process_real_time,
185 double* process_user_time,
186 double* process_system_time);
187
188 // Interface to the performance counter
189 static jlong elapsed_counter();
190 static jlong elapsed_frequency();
191
192 // The "virtual time" of a thread is the amount of time a thread has
193 // actually run. The first function indicates whether the OS supports
194 // this functionality for the current thread, and if so:
195 // * the second enables vtime tracking (if that is required).
196 // * the third tells whether vtime is enabled.
197 // * the fourth returns the elapsed virtual time for the current
198 // thread.
199 static bool supports_vtime();
200 static bool enable_vtime();
201 static bool vtime_enabled();
202 static double elapsedVTime();
203
204 // Return current local time in a string (YYYY-MM-DD HH:MM:SS).
205 // It is MT safe, but not async-safe, as reading time zone
206 // information may require a lock on some platforms.
207 static char* local_time_string(char *buf, size_t buflen);
208 static struct tm* localtime_pd (const time_t* clock, struct tm* res);
209 // Fill in buffer with current local time as an ISO-8601 string.
210 // E.g., YYYY-MM-DDThh:mm:ss.mmm+zzzz.
211 // Returns buffer, or NULL if it failed.
212 static char* iso8601_time(char* buffer, size_t buffer_length);
213
214 // Interface for detecting multiprocessor system
215 static inline bool is_MP() {
216 // During bootstrap if _processor_count is not yet initialized
217 // we claim to be MP as that is safest. If any platform has a
218 // stub generator that might be triggered in this phase and for
219 // which being declared MP when in fact not, is a problem - then
220 // the bootstrap routine for the stub generator needs to check
221 // the processor count directly and leave the bootstrap routine
222 // in place until called after initialization has ocurred.
223 return (_processor_count != 1) || AssumeMP;
224 }
225 static julong available_memory();
226 static julong physical_memory();
227 static bool has_allocatable_memory_limit(julong* limit);
228 static bool is_server_class_machine();
229
230 // number of CPUs
231 static int processor_count() {
232 return _processor_count;
233 }
234 static void set_processor_count(int count) { _processor_count = count; }
235
236 // Returns the number of CPUs this process is currently allowed to run on.
237 // Note that on some OSes this can change dynamically.
238 static int active_processor_count();
239
240 // Bind processes to processors.
241 // This is a two step procedure:
242 // first you generate a distribution of processes to processors,
243 // then you bind processes according to that distribution.
244 // Compute a distribution for number of processes to processors.
245 // Stores the processor id's into the distribution array argument.
246 // Returns true if it worked, false if it didn't.
247 static bool distribute_processes(uint length, uint* distribution);
248 // Binds the current process to a processor.
249 // Returns true if it worked, false if it didn't.
250 static bool bind_to_processor(uint processor_id);
251
252 // Give a name to the current thread.
253 static void set_native_thread_name(const char *name);
254
255 // Interface for stack banging (predetect possible stack overflow for
256 // exception processing) There are guard pages, and above that shadow
257 // pages for stack overflow checking.
258 static bool uses_stack_guard_pages();
259 static bool allocate_stack_guard_pages();
260 static void bang_stack_shadow_pages();
261 static bool stack_shadow_pages_available(Thread *thread, methodHandle method);
262
263 // OS interface to Virtual Memory
264
265 // Return the default page size.
266 static int vm_page_size();
267
268 // Returns the page size to use for a region of memory.
269 // region_size / min_pages will always be greater than or equal to the
270 // returned value.
271 static size_t page_size_for_region(size_t region_size, size_t min_pages);
272
273 // Return the largest page size that can be used
274 static size_t max_page_size() {
275 // The _page_sizes array is sorted in descending order.
276 return _page_sizes[0];
277 }
278
279 // Methods for tracing page sizes returned by the above method; enabled by
280 // TracePageSizes. The region_{min,max}_size parameters should be the values
281 // passed to page_size_for_region() and page_size should be the result of that
282 // call. The (optional) base and size parameters should come from the
283 // ReservedSpace base() and size() methods.
284 static void trace_page_sizes(const char* str, const size_t* page_sizes,
285 int count) PRODUCT_RETURN;
286 static void trace_page_sizes(const char* str, const size_t region_min_size,
287 const size_t region_max_size,
288 const size_t page_size,
289 const char* base = NULL,
290 const size_t size = 0) PRODUCT_RETURN;
291
292 static int vm_allocation_granularity();
293 static char* reserve_memory(size_t bytes, char* addr = 0,
294 size_t alignment_hint = 0);
295 static char* reserve_memory(size_t bytes, char* addr,
296 size_t alignment_hint, MEMFLAGS flags);
297 static char* reserve_memory_aligned(size_t size, size_t alignment);
298 static char* attempt_reserve_memory_at(size_t bytes, char* addr);
299 static void split_reserved_memory(char *base, size_t size,
300 size_t split, bool realloc);
301 static bool commit_memory(char* addr, size_t bytes, bool executable);
302 static bool commit_memory(char* addr, size_t size, size_t alignment_hint,
303 bool executable);
304 // Same as commit_memory() that either succeeds or calls
305 // vm_exit_out_of_memory() with the specified mesg.
306 static void commit_memory_or_exit(char* addr, size_t bytes,
307 bool executable, const char* mesg);
308 static void commit_memory_or_exit(char* addr, size_t size,
309 size_t alignment_hint,
310 bool executable, const char* mesg);
311 static bool uncommit_memory(char* addr, size_t bytes);
312 static bool release_memory(char* addr, size_t bytes);
313
314 // Touch memory pages that cover the memory range from start to end (exclusive)
315 // to make the OS back the memory range with actual memory.
316 // Current implementation may not touch the last page if unaligned addresses
317 // are passed.
318 static void pretouch_memory(char* start, char* end);
319
320 enum ProtType { MEM_PROT_NONE, MEM_PROT_READ, MEM_PROT_RW, MEM_PROT_RWX };
321 static bool protect_memory(char* addr, size_t bytes, ProtType prot,
322 bool is_committed = true);
323
324 static bool guard_memory(char* addr, size_t bytes);
325 static bool unguard_memory(char* addr, size_t bytes);
326 static bool create_stack_guard_pages(char* addr, size_t bytes);
327 static bool pd_create_stack_guard_pages(char* addr, size_t bytes);
328 static bool remove_stack_guard_pages(char* addr, size_t bytes);
329
330 static char* map_memory(int fd, const char* file_name, size_t file_offset,
331 char *addr, size_t bytes, bool read_only = false,
332 bool allow_exec = false);
333 static char* remap_memory(int fd, const char* file_name, size_t file_offset,
334 char *addr, size_t bytes, bool read_only,
335 bool allow_exec);
336 static bool unmap_memory(char *addr, size_t bytes);
337 static void free_memory(char *addr, size_t bytes, size_t alignment_hint);
338 static void realign_memory(char *addr, size_t bytes, size_t alignment_hint);
339
340 // NUMA-specific interface
341 static bool numa_has_static_binding();
342 static bool numa_has_group_homing();
343 static void numa_make_local(char *addr, size_t bytes, int lgrp_hint);
344 static void numa_make_global(char *addr, size_t bytes);
345 static size_t numa_get_groups_num();
346 static size_t numa_get_leaf_groups(int *ids, size_t size);
347 static bool numa_topology_changed();
348 static int numa_get_group_id();
349
350 // Page manipulation
351 struct page_info {
352 size_t size;
353 int lgrp_id;
354 };
355 static bool get_page_info(char *start, page_info* info);
356 static char* scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found);
357
358 static char* non_memory_address_word();
359 // reserve, commit and pin the entire memory region
360 static char* reserve_memory_special(size_t size, size_t alignment,
361 char* addr, bool executable);
362 static bool release_memory_special(char* addr, size_t bytes);
363 static void large_page_init();
364 static size_t large_page_size();
365 static bool can_commit_large_page_memory();
366 static bool can_execute_large_page_memory();
367
368 // OS interface to polling page
369 static address get_polling_page() { return _polling_page; }
370 static void set_polling_page(address page) { _polling_page = page; }
371 static bool is_poll_address(address addr) { return addr >= _polling_page && addr < (_polling_page + os::vm_page_size()); }
372 static void make_polling_page_unreadable();
373 static void make_polling_page_readable();
374
375 // Routines used to serialize the thread state without using membars
376 static void serialize_thread_states();
377
378 // Since we write to the serialize page from every thread, we
379 // want stores to be on unique cache lines whenever possible
380 // in order to minimize CPU cross talk. We pre-compute the
381 // amount to shift the thread* to make this offset unique to
382 // each thread.
383 static int get_serialize_page_shift_count() {
384 return SerializePageShiftCount;
385 }
386
387 static void set_serialize_page_mask(uintptr_t mask) {
388 _serialize_page_mask = mask;
389 }
390
391 static unsigned int get_serialize_page_mask() {
392 return _serialize_page_mask;
393 }
394
395 static void set_memory_serialize_page(address page);
396
397 static address get_memory_serialize_page() {
398 return (address)_mem_serialize_page;
399 }
400
401 static inline void write_memory_serialize_page(JavaThread *thread) {
402 uintptr_t page_offset = ((uintptr_t)thread >>
403 get_serialize_page_shift_count()) &
404 get_serialize_page_mask();
405 *(volatile int32_t *)((uintptr_t)_mem_serialize_page+page_offset) = 1;
406 }
407
408 static bool is_memory_serialize_page(JavaThread *thread, address addr) {
409 if (UseMembar) return false;
410 // Previously this function calculated the exact address of this
411 // thread's serialize page, and checked if the faulting address
412 // was equal. However, some platforms mask off faulting addresses
413 // to the page size, so now we just check that the address is
414 // within the page. This makes the thread argument unnecessary,
415 // but we retain the NULL check to preserve existing behaviour.
416 if (thread == NULL) return false;
417 address page = (address) _mem_serialize_page;
418 return addr >= page && addr < (page + os::vm_page_size());
419 }
420
421 static void block_on_serialize_page_trap();
422
423 // threads
424
425 enum ThreadType {
426 vm_thread,
427 cgc_thread, // Concurrent GC thread
428 pgc_thread, // Parallel GC thread
429 java_thread,
430 compiler_thread,
431 watcher_thread,
432 os_thread
433 };
434
435 static bool create_thread(Thread* thread,
436 ThreadType thr_type,
437 size_t stack_size = 0);
438 static bool create_main_thread(JavaThread* thread);
439 static bool create_attached_thread(JavaThread* thread);
440 static void pd_start_thread(Thread* thread);
441 static void start_thread(Thread* thread);
442
443 static void initialize_thread(Thread* thr);
444 static void free_thread(OSThread* osthread);
445
446 // thread id on Linux/64bit is 64bit, on Windows and Solaris, it's 32bit
447 static intx current_thread_id();
448 static int current_process_id();
449 static int sleep(Thread* thread, jlong ms, bool interruptable);
450 // Short standalone OS sleep suitable for slow path spin loop.
451 // Ignores Thread.interrupt() (so keep it short).
452 // ms = 0, will sleep for the least amount of time allowed by the OS.
453 static void naked_short_sleep(jlong ms);
454 static void infinite_sleep(); // never returns, use with CAUTION
455 static void yield(); // Yields to all threads with same priority
456 enum YieldResult {
457 YIELD_SWITCHED = 1, // caller descheduled, other ready threads exist & ran
458 YIELD_NONEREADY = 0, // No other runnable/ready threads.
459 // platform-specific yield return immediately
460 YIELD_UNKNOWN = -1 // Unknown: platform doesn't support _SWITCHED or _NONEREADY
461 // YIELD_SWITCHED and YIELD_NONREADY imply the platform supports a "strong"
462 // yield that can be used in lieu of blocking.
463 } ;
464 static YieldResult NakedYield () ;
465 static void yield_all(int attempts = 0); // Yields to all other threads including lower priority
466 static void loop_breaker(int attempts); // called from within tight loops to possibly influence time-sharing
467 static OSReturn set_priority(Thread* thread, ThreadPriority priority);
468 static OSReturn get_priority(const Thread* const thread, ThreadPriority& priority);
469
470 static void interrupt(Thread* thread);
471 static bool is_interrupted(Thread* thread, bool clear_interrupted);
472
473 static int pd_self_suspend_thread(Thread* thread);
474
475 static ExtendedPC fetch_frame_from_context(void* ucVoid, intptr_t** sp, intptr_t** fp);
476 static frame fetch_frame_from_context(void* ucVoid);
477
478 static ExtendedPC get_thread_pc(Thread *thread);
479 static void breakpoint();
480
481 static address current_stack_pointer();
482 static address current_stack_base();
483 static size_t current_stack_size();
484
485 static void verify_stack_alignment() PRODUCT_RETURN;
486
487 static int message_box(const char* title, const char* message);
488 static char* do_you_want_to_debug(const char* message);
489
490 // run cmd in a separate process and return its exit code; or -1 on failures
491 static int fork_and_exec(char *cmd);
492
493 // os::exit() is merged with vm_exit()
494 // static void exit(int num);
495
496 // Terminate the VM, but don't exit the process
497 static void shutdown();
498
499 // Terminate with an error. Default is to generate a core file on platforms
500 // that support such things. This calls shutdown() and then aborts.
501 static void abort(bool dump_core = true);
502
503 // Die immediately, no exit hook, no abort hook, no cleanup.
504 static void die();
505
506 // File i/o operations
507 static const int default_file_open_flags();
508 static int open(const char *path, int oflag, int mode);
509 static FILE* open(int fd, const char* mode);
510 static int close(int fd);
511 static jlong lseek(int fd, jlong offset, int whence);
512 static char* native_path(char *path);
513 static int ftruncate(int fd, jlong length);
514 static int fsync(int fd);
515 static int available(int fd, jlong *bytes);
516
517 //File i/o operations
518
519 static size_t read(int fd, void *buf, unsigned int nBytes);
520 static size_t restartable_read(int fd, void *buf, unsigned int nBytes);
521 static size_t write(int fd, const void *buf, unsigned int nBytes);
522
523 // Reading directories.
524 static DIR* opendir(const char* dirname);
525 static int readdir_buf_size(const char *path);
526 static struct dirent* readdir(DIR* dirp, dirent* dbuf);
527 static int closedir(DIR* dirp);
528
529 // Dynamic library extension
530 static const char* dll_file_extension();
531
532 static const char* get_temp_directory();
533 static const char* get_current_directory(char *buf, size_t buflen);
534
535 // Builds a platform-specific full library path given a ld path and lib name
536 // Returns true if buffer contains full path to existing file, false otherwise
537 static bool dll_build_name(char* buffer, size_t size,
538 const char* pathname, const char* fname);
539
540 // Symbol lookup, find nearest function name; basically it implements
541 // dladdr() for all platforms. Name of the nearest function is copied
542 // to buf. Distance from its base address is optionally returned as offset.
543 // If function name is not found, buf[0] is set to '\0' and offset is
544 // set to -1 (if offset is non-NULL).
545 static bool dll_address_to_function_name(address addr, char* buf,
546 int buflen, int* offset);
547
548 // Locate DLL/DSO. On success, full path of the library is copied to
549 // buf, and offset is optionally set to be the distance between addr
550 // and the library's base address. On failure, buf[0] is set to '\0'
551 // and offset is set to -1 (if offset is non-NULL).
552 static bool dll_address_to_library_name(address addr, char* buf,
553 int buflen, int* offset);
554
555 // Find out whether the pc is in the static code for jvm.dll/libjvm.so.
556 static bool address_is_in_vm(address addr);
557
558 // Loads .dll/.so and
559 // in case of error it checks if .dll/.so was built for the
560 // same architecture as Hotspot is running on
561 static void* dll_load(const char *name, char *ebuf, int ebuflen);
562
563 // lookup symbol in a shared library
564 static void* dll_lookup(void* handle, const char* name);
565
566 // Unload library
567 static void dll_unload(void *lib);
568
569 // Return the handle of this process
570 static void* get_default_process_handle();
571
572 // Check for static linked agent library
573 static bool find_builtin_agent(AgentLibrary *agent_lib, const char *syms[],
574 size_t syms_len);
575
576 // Find agent entry point
577 static void *find_agent_function(AgentLibrary *agent_lib, bool check_lib,
578 const char *syms[], size_t syms_len);
579
580 // Print out system information; they are called by fatal error handler.
581 // Output format may be different on different platforms.
582 static void print_os_info(outputStream* st);
583 static void print_os_info_brief(outputStream* st);
584 static void print_cpu_info(outputStream* st);
585 static void pd_print_cpu_info(outputStream* st);
586 static void print_memory_info(outputStream* st);
587 static void print_dll_info(outputStream* st);
588 static void print_environment_variables(outputStream* st, const char** env_list, char* buffer, int len);
589 static void print_context(outputStream* st, void* context);
590 static void print_register_info(outputStream* st, void* context);
591 static void print_siginfo(outputStream* st, void* siginfo);
592 static void print_signal_handlers(outputStream* st, char* buf, size_t buflen);
593 static void print_date_and_time(outputStream* st);
594
595 static void print_location(outputStream* st, intptr_t x, bool verbose = false);
596 static size_t lasterror(char *buf, size_t len);
597 static int get_last_error();
598
599 // Determines whether the calling process is being debugged by a user-mode debugger.
600 static bool is_debugger_attached();
601
602 // wait for a key press if PauseAtExit is set
603 static void wait_for_keypress_at_exit(void);
604
605 // The following two functions are used by fatal error handler to trace
606 // native (C) frames. They are not part of frame.hpp/frame.cpp because
607 // frame.hpp/cpp assume thread is JavaThread, and also because different
608 // OS/compiler may have different convention or provide different API to
609 // walk C frames.
610 //
611 // We don't attempt to become a debugger, so we only follow frames if that
612 // does not require a lookup in the unwind table, which is part of the binary
613 // file but may be unsafe to read after a fatal error. So on x86, we can
614 // only walk stack if %ebp is used as frame pointer; on ia64, it's not
615 // possible to walk C stack without having the unwind table.
616 static bool is_first_C_frame(frame *fr);
617 static frame get_sender_for_C_frame(frame *fr);
618
619 // return current frame. pc() and sp() are set to NULL on failure.
620 static frame current_frame();
621
622 static void print_hex_dump(outputStream* st, address start, address end, int unitsize);
623
624 // returns a string to describe the exception/signal;
625 // returns NULL if exception_code is not an OS exception/signal.
626 static const char* exception_name(int exception_code, char* buf, size_t buflen);
627
628 // Returns native Java library, loads if necessary
629 static void* native_java_library();
630
631 // Fills in path to jvm.dll/libjvm.so (used by the Disassembler)
632 static void jvm_path(char *buf, jint buflen);
633
634 // Returns true if we are running in a headless jre.
635 static bool is_headless_jre();
636
637 // JNI names
638 static void print_jni_name_prefix_on(outputStream* st, int args_size);
639 static void print_jni_name_suffix_on(outputStream* st, int args_size);
640
641 // File conventions
642 static const char* file_separator();
643 static const char* line_separator();
644 static const char* path_separator();
645
646 // Init os specific system properties values
647 static void init_system_properties_values();
648
649 // IO operations, non-JVM_ version.
650 static int stat(const char* path, struct stat* sbuf);
651 static bool dir_is_empty(const char* path);
652
653 // IO operations on binary files
654 static int create_binary_file(const char* path, bool rewrite_existing);
655 static jlong current_file_offset(int fd);
656 static jlong seek_to_file_offset(int fd, jlong offset);
657
658 // Thread Local Storage
659 static int allocate_thread_local_storage();
660 static void thread_local_storage_at_put(int index, void* value);
661 static void* thread_local_storage_at(int index);
662 static void free_thread_local_storage(int index);
663
664 // Retrieve native stack frames.
665 // Parameter:
666 // stack: an array to storage stack pointers.
667 // frames: size of above array.
668 // toSkip: number of stack frames to skip at the beginning.
669 // Return: number of stack frames captured.
670 static int get_native_stack(address* stack, int size, int toSkip = 0);
671
672 // General allocation (must be MT-safe)
673 static void* malloc (size_t size, MEMFLAGS flags, const NativeCallStack& stack);
674 static void* malloc (size_t size, MEMFLAGS flags);
675 static void* realloc (void *memblock, size_t size, MEMFLAGS flag, const NativeCallStack& stack);
676 static void* realloc (void *memblock, size_t size, MEMFLAGS flag);
677
678 static void free (void *memblock, MEMFLAGS flags = mtNone);
679 static bool check_heap(bool force = false); // verify C heap integrity
680 static char* strdup(const char *, MEMFLAGS flags = mtInternal); // Like strdup
681
682 #ifndef PRODUCT
683 static julong num_mallocs; // # of calls to malloc/realloc
684 static julong alloc_bytes; // # of bytes allocated
685 static julong num_frees; // # of calls to free
686 static julong free_bytes; // # of bytes freed
687 #endif
688
689 // SocketInterface (ex HPI SocketInterface )
690 static int socket(int domain, int type, int protocol);
691 static int socket_close(int fd);
692 static int socket_shutdown(int fd, int howto);
693 static int recv(int fd, char* buf, size_t nBytes, uint flags);
694 static int send(int fd, char* buf, size_t nBytes, uint flags);
695 static int raw_send(int fd, char* buf, size_t nBytes, uint flags);
696 static int timeout(int fd, long timeout);
697 static int listen(int fd, int count);
698 static int connect(int fd, struct sockaddr* him, socklen_t len);
699 static int bind(int fd, struct sockaddr* him, socklen_t len);
700 static int accept(int fd, struct sockaddr* him, socklen_t* len);
701 static int recvfrom(int fd, char* buf, size_t nbytes, uint flags,
702 struct sockaddr* from, socklen_t* fromlen);
703 static int get_sock_name(int fd, struct sockaddr* him, socklen_t* len);
704 static int sendto(int fd, char* buf, size_t len, uint flags,
705 struct sockaddr* to, socklen_t tolen);
706 static int socket_available(int fd, jint* pbytes);
707
708 static int get_sock_opt(int fd, int level, int optname,
709 char* optval, socklen_t* optlen);
710 static int set_sock_opt(int fd, int level, int optname,
711 const char* optval, socklen_t optlen);
712 static int get_host_name(char* name, int namelen);
713
714 static struct hostent* get_host_by_name(char* name);
715
716 // Support for signals (see JVM_RaiseSignal, JVM_RegisterSignal)
717 static void signal_init();
718 static void signal_init_pd();
719 static void signal_notify(int signal_number);
720 static void* signal(int signal_number, void* handler);
721 static void signal_raise(int signal_number);
722 static int signal_wait();
723 static int signal_lookup();
724 static void* user_handler();
725 static void terminate_signal_thread();
726 static int sigexitnum_pd();
727
728 // random number generation
729 static long random(); // return 32bit pseudorandom number
730 static void init_random(long initval); // initialize random sequence
731
732 // Structured OS Exception support
733 static void os_exception_wrapper(java_call_t f, JavaValue* value, methodHandle* method, JavaCallArguments* args, Thread* thread);
734
735 // On Windows this will create an actual minidump, on Linux/Solaris it will simply check core dump limits
736 static void check_or_create_dump(void* exceptionRecord, void* contextRecord, char* buffer, size_t bufferSize);
737
738 // Get the default path to the core file
739 // Returns the length of the string
740 static int get_core_path(char* buffer, size_t bufferSize);
741
742 // JVMTI & JVM monitoring and management support
743 // The thread_cpu_time() and current_thread_cpu_time() are only
744 // supported if is_thread_cpu_time_supported() returns true.
745 // They are not supported on Solaris T1.
746
747 // Thread CPU Time - return the fast estimate on a platform
748 // On Solaris - call gethrvtime (fast) - user time only
749 // On Linux - fast clock_gettime where available - user+sys
750 // - otherwise: very slow /proc fs - user+sys
751 // On Windows - GetThreadTimes - user+sys
752 static jlong current_thread_cpu_time();
753 static jlong thread_cpu_time(Thread* t);
754
755 // Thread CPU Time with user_sys_cpu_time parameter.
756 //
757 // If user_sys_cpu_time is true, user+sys time is returned.
758 // Otherwise, only user time is returned
759 static jlong current_thread_cpu_time(bool user_sys_cpu_time);
760 static jlong thread_cpu_time(Thread* t, bool user_sys_cpu_time);
761
762 // Return a bunch of info about the timers.
763 // Note that the returned info for these two functions may be different
764 // on some platforms
765 static void current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr);
766 static void thread_cpu_time_info(jvmtiTimerInfo *info_ptr);
767
768 static bool is_thread_cpu_time_supported();
769
770 // System loadavg support. Returns -1 if load average cannot be obtained.
771 static int loadavg(double loadavg[], int nelem);
772
773 // Hook for os specific jvm options that we don't want to abort on seeing
774 static bool obsolete_option(const JavaVMOption *option);
775
776 // Extensions
777 #include "runtime/os_ext.hpp"
778
779 public:
780 class CrashProtectionCallback : public StackObj {
781 public:
782 virtual void call() = 0;
783 };
784
785 // Platform dependent stuff
786 #ifdef TARGET_OS_FAMILY_linux
787 # include "os_linux.hpp"
788 # include "os_posix.hpp"
789 #endif
790 #ifdef TARGET_OS_FAMILY_solaris
791 # include "os_solaris.hpp"
792 # include "os_posix.hpp"
793 #endif
794 #ifdef TARGET_OS_FAMILY_windows
795 # include "os_windows.hpp"
796 #endif
797 #ifdef TARGET_OS_FAMILY_aix
798 # include "os_aix.hpp"
799 # include "os_posix.hpp"
800 #endif
801 #ifdef TARGET_OS_FAMILY_bsd
802 # include "os_posix.hpp"
803 # include "os_bsd.hpp"
804 #endif
805 #ifdef TARGET_OS_ARCH_linux_x86
806 # include "os_linux_x86.hpp"
807 #endif
808 #ifdef TARGET_OS_ARCH_linux_sparc
809 # include "os_linux_sparc.hpp"
810 #endif
811 #ifdef TARGET_OS_ARCH_linux_zero
812 # include "os_linux_zero.hpp"
813 #endif
814 #ifdef TARGET_OS_ARCH_solaris_x86
815 # include "os_solaris_x86.hpp"
816 #endif
817 #ifdef TARGET_OS_ARCH_solaris_sparc
818 # include "os_solaris_sparc.hpp"
819 #endif
820 #ifdef TARGET_OS_ARCH_windows_x86
821 # include "os_windows_x86.hpp"
822 #endif
823 #ifdef TARGET_OS_ARCH_linux_arm
824 # include "os_linux_arm.hpp"
825 #endif
826 #ifdef TARGET_OS_ARCH_linux_ppc
827 # include "os_linux_ppc.hpp"
828 #endif
829 #ifdef TARGET_OS_ARCH_aix_ppc
830 # include "os_aix_ppc.hpp"
831 #endif
832 #ifdef TARGET_OS_ARCH_bsd_x86
833 # include "os_bsd_x86.hpp"
834 #endif
835 #ifdef TARGET_OS_ARCH_bsd_zero
836 # include "os_bsd_zero.hpp"
837 #endif
838
839 public:
840 #ifndef PLATFORM_PRINT_NATIVE_STACK
841 // No platform-specific code for printing the native stack.
842 static bool platform_print_native_stack(outputStream* st, void* context,
843 char *buf, int buf_size) {
844 return false;
845 }
846 #endif
847
848 // debugging support (mostly used by debug.cpp but also fatal error handler)
849 static bool find(address pc, outputStream* st = tty); // OS specific function to make sense out of an address
850
851 static bool dont_yield(); // when true, JVM_Yield() is nop
852 static void print_statistics();
853
854 // Thread priority helpers (implemented in OS-specific part)
855 static OSReturn set_native_priority(Thread* thread, int native_prio);
856 static OSReturn get_native_priority(const Thread* const thread, int* priority_ptr);
857 static int java_to_os_priority[CriticalPriority + 1];
858 // Hint to the underlying OS that a task switch would not be good.
859 // Void return because it's a hint and can fail.
860 static void hint_no_preempt();
861
862 // Used at creation if requested by the diagnostic flag PauseAtStartup.
863 // Causes the VM to wait until an external stimulus has been applied
864 // (for Unix, that stimulus is a signal, for Windows, an external
865 // ResumeThread call)
866 static void pause();
867
868 // Builds a platform dependent Agent_OnLoad_<libname> function name
869 // which is used to find statically linked in agents.
870 static char* build_agent_function_name(const char *sym, const char *cname,
871 bool is_absolute_path);
872
873 class SuspendedThreadTaskContext {
874 public:
875 SuspendedThreadTaskContext(Thread* thread, void *ucontext) : _thread(thread), _ucontext(ucontext) {}
876 Thread* thread() const { return _thread; }
877 void* ucontext() const { return _ucontext; }
878 private:
879 Thread* _thread;
880 void* _ucontext;
881 };
882
883 class SuspendedThreadTask {
884 public:
885 SuspendedThreadTask(Thread* thread) : _thread(thread), _done(false) {}
886 virtual ~SuspendedThreadTask() {}
887 void run();
888 bool is_done() { return _done; }
889 virtual void do_task(const SuspendedThreadTaskContext& context) = 0;
890 protected:
891 private:
892 void internal_do_task();
893 Thread* _thread;
894 bool _done;
895 };
896
897 #ifndef TARGET_OS_FAMILY_windows
898 // Suspend/resume support
899 // Protocol:
900 //
901 // a thread starts in SR_RUNNING
902 //
903 // SR_RUNNING can go to
904 // * SR_SUSPEND_REQUEST when the WatcherThread wants to suspend it
905 // SR_SUSPEND_REQUEST can go to
906 // * SR_RUNNING if WatcherThread decides it waited for SR_SUSPENDED too long (timeout)
907 // * SR_SUSPENDED if the stopped thread receives the signal and switches state
908 // SR_SUSPENDED can go to
909 // * SR_WAKEUP_REQUEST when the WatcherThread has done the work and wants to resume
910 // SR_WAKEUP_REQUEST can go to
911 // * SR_RUNNING when the stopped thread receives the signal
912 // * SR_WAKEUP_REQUEST on timeout (resend the signal and try again)
913 class SuspendResume {
914 public:
915 enum State {
916 SR_RUNNING,
917 SR_SUSPEND_REQUEST,
918 SR_SUSPENDED,
919 SR_WAKEUP_REQUEST
920 };
921
922 private:
923 volatile State _state;
924
925 private:
926 /* try to switch state from state "from" to state "to"
927 * returns the state set after the method is complete
928 */
929 State switch_state(State from, State to);
930
931 public:
932 SuspendResume() : _state(SR_RUNNING) { }
933
934 State state() const { return _state; }
935
936 State request_suspend() {
937 return switch_state(SR_RUNNING, SR_SUSPEND_REQUEST);
938 }
939
940 State cancel_suspend() {
941 return switch_state(SR_SUSPEND_REQUEST, SR_RUNNING);
942 }
943
944 State suspended() {
945 return switch_state(SR_SUSPEND_REQUEST, SR_SUSPENDED);
946 }
947
948 State request_wakeup() {
949 return switch_state(SR_SUSPENDED, SR_WAKEUP_REQUEST);
950 }
951
952 State running() {
953 return switch_state(SR_WAKEUP_REQUEST, SR_RUNNING);
954 }
955
956 bool is_running() const {
957 return _state == SR_RUNNING;
958 }
959
960 bool is_suspend_request() const {
961 return _state == SR_SUSPEND_REQUEST;
962 }
963
964 bool is_suspended() const {
965 return _state == SR_SUSPENDED;
966 }
967 };
968 #endif
969
970
971 protected:
972 static long _rand_seed; // seed for random number generator
973 static int _processor_count; // number of processors
974
975 static char* format_boot_path(const char* format_string,
976 const char* home,
977 int home_len,
978 char fileSep,
979 char pathSep);
980 static bool set_boot_path(char fileSep, char pathSep);
981 static char** split_path(const char* path, int* n);
982
983 };
984
985 // Note that "PAUSE" is almost always used with synchronization
986 // so arguably we should provide Atomic::SpinPause() instead
987 // of the global SpinPause() with C linkage.
988 // It'd also be eligible for inlining on many platforms.
989
990 extern "C" int SpinPause();
991
992 #endif // SHARE_VM_RUNTIME_OS_HPP