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_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 template<class E> class GrowableArray;
70
71 // %%%%% Moved ThreadState, START_FN, OSThread to new osThread.hpp. -- Rose
72
73 // Platform-independent error return values from OS functions
74 enum OSReturn {
75 OS_OK = 0, // Operation was successful
76 OS_ERR = -1, // Operation failed
77 OS_INTRPT = -2, // Operation was interrupted
78 OS_TIMEOUT = -3, // Operation timed out
79 OS_NOMEM = -5, // Operation failed for lack of memory
80 OS_NORESOURCE = -6 // Operation failed for lack of nonmemory resource
81 };
82
83 enum ThreadPriority { // JLS 20.20.1-3
84 NoPriority = -1, // Initial non-priority value
85 MinPriority = 1, // Minimum priority
86 NormPriority = 5, // Normal (non-daemon) priority
87 NearMaxPriority = 9, // High priority, used for VMThread
88 MaxPriority = 10, // Highest priority, used for WatcherThread
89 // ensures that VMThread doesn't starve profiler
90 CriticalPriority = 11 // Critical thread priority
91 };
92
93 // Executable parameter flag for os::commit_memory() and
94 // os::commit_memory_or_exit().
95 const bool ExecMem = true;
96
97 // Typedef for structured exception handling support
98 typedef void (*java_call_t)(JavaValue* value, methodHandle* method, JavaCallArguments* args, Thread* thread);
99
100 class os: AllStatic {
101 friend class VMStructs;
102
103 public:
104 enum { page_sizes_max = 9 }; // Size of _page_sizes array (8 plus a sentinel)
105
106 private:
107 static OSThread* _starting_thread;
108 static address _polling_page;
109 static volatile int32_t * _mem_serialize_page;
110 static uintptr_t _serialize_page_mask;
111 public:
112 static size_t _page_sizes[page_sizes_max];
113
114 private:
115 static void init_page_sizes(size_t default_page_size) {
116 _page_sizes[0] = default_page_size;
117 _page_sizes[1] = 0; // sentinel
118 }
119
120 static char* pd_reserve_memory(size_t bytes, char* addr = 0,
121 size_t alignment_hint = 0);
122 static char* pd_attempt_reserve_memory_at(size_t bytes, char* addr);
123 static void pd_split_reserved_memory(char *base, size_t size,
124 size_t split, bool realloc);
125 static bool pd_commit_memory(char* addr, size_t bytes, bool executable);
126 static bool pd_commit_memory(char* addr, size_t size, size_t alignment_hint,
127 bool executable);
128 // Same as pd_commit_memory() that either succeeds or calls
129 // vm_exit_out_of_memory() with the specified mesg.
130 static void pd_commit_memory_or_exit(char* addr, size_t bytes,
131 bool executable, const char* mesg);
132 static void pd_commit_memory_or_exit(char* addr, size_t size,
133 size_t alignment_hint,
134 bool executable, const char* mesg);
135 static bool pd_uncommit_memory(char* addr, size_t bytes);
136 static bool pd_release_memory(char* addr, size_t bytes);
137
138 static char* pd_map_memory(int fd, const char* file_name, size_t file_offset,
139 char *addr, size_t bytes, bool read_only = false,
140 bool allow_exec = false);
141 static char* pd_remap_memory(int fd, const char* file_name, size_t file_offset,
142 char *addr, size_t bytes, bool read_only,
143 bool allow_exec);
144 static bool pd_unmap_memory(char *addr, size_t bytes);
145 static void pd_free_memory(char *addr, size_t bytes, size_t alignment_hint);
146 static void pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint);
147
148
149 public:
150 static void init(void); // Called before command line parsing
151 static void init_before_ergo(void); // Called after command line parsing
152 // before VM ergonomics processing.
153 static jint init_2(void); // Called after command line parsing
154 // and VM ergonomics processing
155 static void init_globals(void) { // Called from init_globals() in init.cpp
156 init_globals_ext();
157 }
158 static void init_3(void); // Called at the end of vm init
159
160 // File names are case-insensitive on windows only
161 // Override me as needed
162 static int file_name_strcmp(const char* s1, const char* s2);
163
164 static bool getenv(const char* name, char* buffer, int len);
165 static bool have_special_privileges();
166
167 static jlong javaTimeMillis();
168 static jlong javaTimeNanos();
169 static void javaTimeNanos_info(jvmtiTimerInfo *info_ptr);
170 static void run_periodic_checks();
171
172
173 // Returns the elapsed time in seconds since the vm started.
174 static double elapsedTime();
175
176 // Returns real time in seconds since an arbitrary point
177 // in the past.
178 static bool getTimesSecs(double* process_real_time,
179 double* process_user_time,
180 double* process_system_time);
181
182 // Interface to the performance counter
183 static jlong elapsed_counter();
184 static jlong elapsed_frequency();
185
186 // The "virtual time" of a thread is the amount of time a thread has
187 // actually run. The first function indicates whether the OS supports
188 // this functionality for the current thread, and if so:
189 // * the second enables vtime tracking (if that is required).
190 // * the third tells whether vtime is enabled.
191 // * the fourth returns the elapsed virtual time for the current
192 // thread.
193 static bool supports_vtime();
194 static bool enable_vtime();
195 static bool vtime_enabled();
196 static double elapsedVTime();
197
198 // Return current local time in a string (YYYY-MM-DD HH:MM:SS).
199 // It is MT safe, but not async-safe, as reading time zone
200 // information may require a lock on some platforms.
201 static char* local_time_string(char *buf, size_t buflen);
202 static struct tm* localtime_pd (const time_t* clock, struct tm* res);
203 // Fill in buffer with current local time as an ISO-8601 string.
204 // E.g., YYYY-MM-DDThh:mm:ss.mmm+zzzz.
205 // Returns buffer, or NULL if it failed.
206 static char* iso8601_time(char* buffer, size_t buffer_length);
207
208 // Interface for detecting multiprocessor system
209 static inline bool is_MP() {
210 assert(_processor_count > 0, "invalid processor count");
211 return _processor_count > 1 || AssumeMP;
212 }
213 static julong available_memory();
214 static julong physical_memory();
215 static bool has_allocatable_memory_limit(julong* limit);
216 static bool is_server_class_machine();
217
218 // number of CPUs
219 static int processor_count() {
220 return _processor_count;
221 }
222 static void set_processor_count(int count) { _processor_count = count; }
223
224 // Returns the number of CPUs this process is currently allowed to run on.
225 // Note that on some OSes this can change dynamically.
226 static int active_processor_count();
227
228 // Bind processes to processors.
229 // This is a two step procedure:
230 // first you generate a distribution of processes to processors,
231 // then you bind processes according to that distribution.
232 // Compute a distribution for number of processes to processors.
233 // Stores the processor id's into the distribution array argument.
234 // Returns true if it worked, false if it didn't.
235 static bool distribute_processes(uint length, uint* distribution);
236 // Binds the current process to a processor.
237 // Returns true if it worked, false if it didn't.
238 static bool bind_to_processor(uint processor_id);
239
240 // Give a name to the current thread.
241 static void set_native_thread_name(const char *name);
242
243 // Interface for stack banging (predetect possible stack overflow for
244 // exception processing) There are guard pages, and above that shadow
245 // pages for stack overflow checking.
246 static bool uses_stack_guard_pages();
247 static bool allocate_stack_guard_pages();
248 static void bang_stack_shadow_pages();
249 static bool stack_shadow_pages_available(Thread *thread, methodHandle method);
250
251 // OS interface to Virtual Memory
252
253 // Return the default page size.
254 static int vm_page_size();
255
256 // Return the page size to use for a region of memory. The min_pages argument
257 // is a hint intended to limit fragmentation; it says the returned page size
258 // should be <= region_max_size / min_pages. Because min_pages is a hint,
259 // this routine may return a size larger than region_max_size / min_pages.
260 //
261 // The current implementation ignores min_pages if a larger page size is an
262 // exact multiple of both region_min_size and region_max_size. This allows
263 // larger pages to be used when doing so would not cause fragmentation; in
264 // particular, a single page can be used when region_min_size ==
265 // region_max_size == a supported page size.
266 static size_t page_size_for_region(size_t region_min_size,
267 size_t region_max_size,
268 uint min_pages);
269 // Return the largest page size that can be used
270 static size_t max_page_size() {
271 // The _page_sizes array is sorted in descending order.
272 return _page_sizes[0];
273 }
274
275 // Methods for tracing page sizes returned by the above method; enabled by
276 // TracePageSizes. The region_{min,max}_size parameters should be the values
277 // passed to page_size_for_region() and page_size should be the result of that
278 // call. The (optional) base and size parameters should come from the
279 // ReservedSpace base() and size() methods.
280 static void trace_page_sizes(const char* str, const size_t* page_sizes,
281 int count) PRODUCT_RETURN;
282 static void trace_page_sizes(const char* str, const size_t region_min_size,
283 const size_t region_max_size,
284 const size_t page_size,
285 const char* base = NULL,
286 const size_t size = 0) PRODUCT_RETURN;
287
288 static int vm_allocation_granularity();
289 static char* reserve_memory(size_t bytes, char* addr = 0,
290 size_t alignment_hint = 0);
291 static char* reserve_memory(size_t bytes, char* addr,
292 size_t alignment_hint, MEMFLAGS flags);
293 static char* reserve_memory_aligned(size_t size, size_t alignment);
294 static char* attempt_reserve_memory_at(size_t bytes, char* addr);
295 static void split_reserved_memory(char *base, size_t size,
296 size_t split, bool realloc);
297 static bool commit_memory(char* addr, size_t bytes, bool executable);
298 static bool commit_memory(char* addr, size_t size, size_t alignment_hint,
299 bool executable);
300 // Same as commit_memory() that either succeeds or calls
301 // vm_exit_out_of_memory() with the specified mesg.
302 static void commit_memory_or_exit(char* addr, size_t bytes,
303 bool executable, const char* mesg);
304 static void commit_memory_or_exit(char* addr, size_t size,
305 size_t alignment_hint,
306 bool executable, const char* mesg);
307 static bool uncommit_memory(char* addr, size_t bytes);
308 static bool release_memory(char* addr, size_t bytes);
309
310 enum ProtType { MEM_PROT_NONE, MEM_PROT_READ, MEM_PROT_RW, MEM_PROT_RWX };
311 static bool protect_memory(char* addr, size_t bytes, ProtType prot,
312 bool is_committed = true);
313
314 static bool guard_memory(char* addr, size_t bytes);
315 static bool unguard_memory(char* addr, size_t bytes);
316 static bool create_stack_guard_pages(char* addr, size_t bytes);
317 static bool pd_create_stack_guard_pages(char* addr, size_t bytes);
318 static bool remove_stack_guard_pages(char* addr, size_t bytes);
319
320 static char* map_memory(int fd, const char* file_name, size_t file_offset,
321 char *addr, size_t bytes, bool read_only = false,
322 bool allow_exec = false);
323 static char* remap_memory(int fd, const char* file_name, size_t file_offset,
324 char *addr, size_t bytes, bool read_only,
325 bool allow_exec);
326 static bool unmap_memory(char *addr, size_t bytes);
327 static void free_memory(char *addr, size_t bytes, size_t alignment_hint);
328 static void realign_memory(char *addr, size_t bytes, size_t alignment_hint);
329
330 // NUMA-specific interface
331 static bool numa_has_static_binding();
332 static bool numa_has_group_homing();
333 static void numa_make_local(char *addr, size_t bytes, int lgrp_hint);
334 static void numa_make_global(char *addr, size_t bytes);
335 static size_t numa_get_groups_num();
336 static size_t numa_get_leaf_groups(int *ids, size_t size);
337 static bool numa_topology_changed();
338 static int numa_get_group_id();
339
340 // Page manipulation
341 struct page_info {
342 size_t size;
343 int lgrp_id;
344 };
345 static bool get_page_info(char *start, page_info* info);
346 static char* scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found);
347
348 static char* non_memory_address_word();
349 // reserve, commit and pin the entire memory region
350 static char* reserve_memory_special(size_t size, size_t alignment,
351 char* addr, bool executable);
352 static bool release_memory_special(char* addr, size_t bytes);
353 static void large_page_init();
354 static size_t large_page_size();
355 static bool can_commit_large_page_memory();
356 static bool can_execute_large_page_memory();
357
358 // OS interface to polling page
359 static address get_polling_page() { return _polling_page; }
360 static void set_polling_page(address page) { _polling_page = page; }
361 static bool is_poll_address(address addr) { return addr >= _polling_page && addr < (_polling_page + os::vm_page_size()); }
362 static void make_polling_page_unreadable();
363 static void make_polling_page_readable();
364
365 // Routines used to serialize the thread state without using membars
366 static void serialize_thread_states();
367
368 // Since we write to the serialize page from every thread, we
369 // want stores to be on unique cache lines whenever possible
370 // in order to minimize CPU cross talk. We pre-compute the
371 // amount to shift the thread* to make this offset unique to
372 // each thread.
373 static int get_serialize_page_shift_count() {
374 return SerializePageShiftCount;
375 }
376
377 static void set_serialize_page_mask(uintptr_t mask) {
378 _serialize_page_mask = mask;
379 }
380
381 static unsigned int get_serialize_page_mask() {
382 return _serialize_page_mask;
383 }
384
385 static void set_memory_serialize_page(address page);
386
387 static address get_memory_serialize_page() {
388 return (address)_mem_serialize_page;
389 }
390
391 static inline void write_memory_serialize_page(JavaThread *thread) {
392 uintptr_t page_offset = ((uintptr_t)thread >>
393 get_serialize_page_shift_count()) &
394 get_serialize_page_mask();
395 *(volatile int32_t *)((uintptr_t)_mem_serialize_page+page_offset) = 1;
396 }
397
398 static bool is_memory_serialize_page(JavaThread *thread, address addr) {
399 if (UseMembar) return false;
400 // Previously this function calculated the exact address of this
401 // thread's serialize page, and checked if the faulting address
402 // was equal. However, some platforms mask off faulting addresses
403 // to the page size, so now we just check that the address is
404 // within the page. This makes the thread argument unnecessary,
405 // but we retain the NULL check to preserve existing behaviour.
406 if (thread == NULL) return false;
407 address page = (address) _mem_serialize_page;
408 return addr >= page && addr < (page + os::vm_page_size());
409 }
410
411 static void block_on_serialize_page_trap();
412
413 // threads
414
415 enum ThreadType {
416 vm_thread,
417 cgc_thread, // Concurrent GC thread
418 pgc_thread, // Parallel GC thread
419 java_thread,
420 compiler_thread,
421 watcher_thread,
422 os_thread
423 };
424
425 static bool create_thread(Thread* thread,
426 ThreadType thr_type,
427 size_t stack_size = 0);
428 static bool create_main_thread(JavaThread* thread);
429 static bool create_attached_thread(JavaThread* thread);
430 static void pd_start_thread(Thread* thread);
431 static void start_thread(Thread* thread);
432
433 static void initialize_thread(Thread* thr);
434 static void free_thread(OSThread* osthread);
435
436 // thread id on Linux/64bit is 64bit, on Windows and Solaris, it's 32bit
437 static intx current_thread_id();
438 static int current_process_id();
439 static int sleep(Thread* thread, jlong ms, bool interruptable);
440 // Short standalone OS sleep suitable for slow path spin loop.
441 // Ignores Thread.interrupt() (so keep it short).
442 // ms = 0, will sleep for the least amount of time allowed by the OS.
443 static void naked_short_sleep(jlong ms);
444 static void infinite_sleep(); // never returns, use with CAUTION
445 static void yield(); // Yields to all threads with same priority
446 enum YieldResult {
447 YIELD_SWITCHED = 1, // caller descheduled, other ready threads exist & ran
448 YIELD_NONEREADY = 0, // No other runnable/ready threads.
449 // platform-specific yield return immediately
450 YIELD_UNKNOWN = -1 // Unknown: platform doesn't support _SWITCHED or _NONEREADY
451 // YIELD_SWITCHED and YIELD_NONREADY imply the platform supports a "strong"
452 // yield that can be used in lieu of blocking.
453 } ;
454 static YieldResult NakedYield () ;
455 static void yield_all(int attempts = 0); // Yields to all other threads including lower priority
456 static void loop_breaker(int attempts); // called from within tight loops to possibly influence time-sharing
457 static OSReturn set_priority(Thread* thread, ThreadPriority priority);
458 static OSReturn get_priority(const Thread* const thread, ThreadPriority& priority);
459
460 static void interrupt(Thread* thread);
461 static bool is_interrupted(Thread* thread, bool clear_interrupted);
462
463 static int pd_self_suspend_thread(Thread* thread);
464
465 static ExtendedPC fetch_frame_from_context(void* ucVoid, intptr_t** sp, intptr_t** fp);
466 static frame fetch_frame_from_context(void* ucVoid);
467
468 static ExtendedPC get_thread_pc(Thread *thread);
469 static void breakpoint();
470
471 static address current_stack_pointer();
472 static address current_stack_base();
473 static size_t current_stack_size();
474
475 static void verify_stack_alignment() PRODUCT_RETURN;
476
477 static int message_box(const char* title, const char* message);
478 static char* do_you_want_to_debug(const char* message);
479
480 // run cmd in a separate process and return its exit code; or -1 on failures
481 static int fork_and_exec(char *cmd);
482
483 // Set file to send error reports.
484 static void set_error_file(const char *logfile);
485
486 // os::exit() is merged with vm_exit()
487 // static void exit(int num);
488
489 // Terminate the VM, but don't exit the process
490 static void shutdown();
491
492 // Terminate with an error. Default is to generate a core file on platforms
493 // that support such things. This calls shutdown() and then aborts.
494 static void abort(bool dump_core = true);
495
496 // Die immediately, no exit hook, no abort hook, no cleanup.
497 static void die();
498
499 // File i/o operations
500 static const int default_file_open_flags();
501 static int open(const char *path, int oflag, int mode);
502 static FILE* open(int fd, const char* mode);
503 static int close(int fd);
504 static jlong lseek(int fd, jlong offset, int whence);
505 static char* native_path(char *path);
506 static int ftruncate(int fd, jlong length);
507 static int fsync(int fd);
508 static int available(int fd, jlong *bytes);
509
510 //File i/o operations
511
512 static size_t read(int fd, void *buf, unsigned int nBytes);
513 static size_t restartable_read(int fd, void *buf, unsigned int nBytes);
514 static size_t write(int fd, const void *buf, unsigned int nBytes);
515
516 // Reading directories.
517 static DIR* opendir(const char* dirname);
518 static int readdir_buf_size(const char *path);
519 static struct dirent* readdir(DIR* dirp, dirent* dbuf);
520 static int closedir(DIR* dirp);
521
522 // Dynamic library extension
523 static const char* dll_file_extension();
524
525 static const char* get_temp_directory();
526 static const char* get_current_directory(char *buf, size_t buflen);
527
528 // Builds a platform-specific full library path given a ld path and lib name
529 // Returns true if buffer contains full path to existing file, false otherwise
530 static bool dll_build_name(char* buffer, size_t size,
531 const char* pathname, const char* fname);
532
533 // Symbol lookup, find nearest function name; basically it implements
534 // dladdr() for all platforms. Name of the nearest function is copied
535 // to buf. Distance from its base address is optionally returned as offset.
536 // If function name is not found, buf[0] is set to '\0' and offset is
537 // set to -1 (if offset is non-NULL).
538 static bool dll_address_to_function_name(address addr, char* buf,
539 int buflen, int* offset);
540
541 // Locate DLL/DSO. On success, full path of the library is copied to
542 // buf, and offset is optionally set to be the distance between addr
543 // and the library's base address. On failure, buf[0] is set to '\0'
544 // and offset is set to -1 (if offset is non-NULL).
545 static bool dll_address_to_library_name(address addr, char* buf,
546 int buflen, int* offset);
547
548 // Find out whether the pc is in the static code for jvm.dll/libjvm.so.
549 static bool address_is_in_vm(address addr);
550
551 // Loads .dll/.so and
552 // in case of error it checks if .dll/.so was built for the
553 // same architecture as Hotspot is running on
554 static void* dll_load(const char *name, char *ebuf, int ebuflen);
555
556 // lookup symbol in a shared library
557 static void* dll_lookup(void* handle, const char* name);
558
559 // Unload library
560 static void dll_unload(void *lib);
561
562 // Return the handle of this process
563 static void* get_default_process_handle();
564
565 // Check for static linked agent library
566 static bool find_builtin_agent(AgentLibrary *agent_lib, const char *syms[],
567 size_t syms_len);
568
569 // Find agent entry point
570 static void *find_agent_function(AgentLibrary *agent_lib, bool check_lib,
571 const char *syms[], size_t syms_len);
572
573 // Print out system information; they are called by fatal error handler.
574 // Output format may be different on different platforms.
575 static void print_os_info(outputStream* st);
576 static void print_os_info_brief(outputStream* st);
577 static void print_cpu_info(outputStream* st);
578 static void pd_print_cpu_info(outputStream* st);
579 static void print_memory_info(outputStream* st);
580 static void print_dll_info(outputStream* st);
581 static void print_environment_variables(outputStream* st, const char** env_list, char* buffer, int len);
582 static void print_context(outputStream* st, void* context);
583 static void print_register_info(outputStream* st, void* context);
584 static void print_siginfo(outputStream* st, void* siginfo);
585 static void print_signal_handlers(outputStream* st, char* buf, size_t buflen);
586 static void print_date_and_time(outputStream* st);
587
588 static void print_location(outputStream* st, intptr_t x, bool verbose = false);
589 static size_t lasterror(char *buf, size_t len);
590 static int get_last_error();
591
592 // Determines whether the calling process is being debugged by a user-mode debugger.
593 static bool is_debugger_attached();
594
595 // wait for a key press if PauseAtExit is set
596 static void wait_for_keypress_at_exit(void);
597
598 // The following two functions are used by fatal error handler to trace
599 // native (C) frames. They are not part of frame.hpp/frame.cpp because
600 // frame.hpp/cpp assume thread is JavaThread, and also because different
601 // OS/compiler may have different convention or provide different API to
602 // walk C frames.
603 //
604 // We don't attempt to become a debugger, so we only follow frames if that
605 // does not require a lookup in the unwind table, which is part of the binary
606 // file but may be unsafe to read after a fatal error. So on x86, we can
607 // only walk stack if %ebp is used as frame pointer; on ia64, it's not
608 // possible to walk C stack without having the unwind table.
609 static bool is_first_C_frame(frame *fr);
610 static frame get_sender_for_C_frame(frame *fr);
611
612 // return current frame. pc() and sp() are set to NULL on failure.
613 static frame current_frame();
614
615 static void print_hex_dump(outputStream* st, address start, address end, int unitsize);
616
617 // returns a string to describe the exception/signal;
618 // returns NULL if exception_code is not an OS exception/signal.
619 static const char* exception_name(int exception_code, char* buf, size_t buflen);
620
621 // Returns native Java library, loads if necessary
622 static void* native_java_library();
623
624 // Fills in path to jvm.dll/libjvm.so (used by the Disassembler)
625 static void jvm_path(char *buf, jint buflen);
626
627 // Returns true if we are running in a headless jre.
628 static bool is_headless_jre();
629
630 // JNI names
631 static void print_jni_name_prefix_on(outputStream* st, int args_size);
632 static void print_jni_name_suffix_on(outputStream* st, int args_size);
633
634 // File conventions
635 static const char* file_separator();
636 static const char* line_separator();
637 static const char* path_separator();
638
639 // Init os specific system properties values
640 static void init_system_properties_values();
641
642 // IO operations, non-JVM_ version.
643 static int stat(const char* path, struct stat* sbuf);
644 static bool dir_is_empty(const char* path);
645
646 // IO operations on binary files
647 static int create_binary_file(const char* path, bool rewrite_existing);
648 static jlong current_file_offset(int fd);
649 static jlong seek_to_file_offset(int fd, jlong offset);
650
651 // Thread Local Storage
652 static int allocate_thread_local_storage();
653 static void thread_local_storage_at_put(int index, void* value);
654 static void* thread_local_storage_at(int index);
655 static void free_thread_local_storage(int index);
656
657 // Stack walk
658 static address get_caller_pc(int n = 0);
659
660 // General allocation (must be MT-safe)
661 static void* malloc (size_t size, MEMFLAGS flags, address caller_pc = 0);
662 static void* realloc (void *memblock, size_t size, MEMFLAGS flags, address caller_pc = 0);
663 static void free (void *memblock, MEMFLAGS flags = mtNone);
664 static bool check_heap(bool force = false); // verify C heap integrity
665 static char* strdup(const char *, MEMFLAGS flags = mtInternal); // Like strdup
666
667 #ifndef PRODUCT
668 static julong num_mallocs; // # of calls to malloc/realloc
669 static julong alloc_bytes; // # of bytes allocated
670 static julong num_frees; // # of calls to free
671 static julong free_bytes; // # of bytes freed
672 #endif
673
674 // SocketInterface (ex HPI SocketInterface )
675 static int socket(int domain, int type, int protocol);
676 static int socket_close(int fd);
677 static int socket_shutdown(int fd, int howto);
678 static int recv(int fd, char* buf, size_t nBytes, uint flags);
679 static int send(int fd, char* buf, size_t nBytes, uint flags);
680 static int raw_send(int fd, char* buf, size_t nBytes, uint flags);
681 static int timeout(int fd, long timeout);
682 static int listen(int fd, int count);
683 static int connect(int fd, struct sockaddr* him, socklen_t len);
684 static int bind(int fd, struct sockaddr* him, socklen_t len);
685 static int accept(int fd, struct sockaddr* him, socklen_t* len);
686 static int recvfrom(int fd, char* buf, size_t nbytes, uint flags,
687 struct sockaddr* from, socklen_t* fromlen);
688 static int get_sock_name(int fd, struct sockaddr* him, socklen_t* len);
689 static int sendto(int fd, char* buf, size_t len, uint flags,
690 struct sockaddr* to, socklen_t tolen);
691 static int socket_available(int fd, jint* pbytes);
692
693 static int get_sock_opt(int fd, int level, int optname,
694 char* optval, socklen_t* optlen);
695 static int set_sock_opt(int fd, int level, int optname,
696 const char* optval, socklen_t optlen);
697 static int get_host_name(char* name, int namelen);
698
699 static struct hostent* get_host_by_name(char* name);
700
701 // Support for signals (see JVM_RaiseSignal, JVM_RegisterSignal)
702 static void signal_init();
703 static void signal_init_pd();
704 static void signal_notify(int signal_number);
705 static void* signal(int signal_number, void* handler);
706 static void signal_raise(int signal_number);
707 static int signal_wait();
708 static int signal_lookup();
709 static void* user_handler();
710 static void terminate_signal_thread();
711 static int sigexitnum_pd();
712
713 // random number generation
714 static long random(); // return 32bit pseudorandom number
715 static void init_random(long initval); // initialize random sequence
716
717 // Structured OS Exception support
718 static void os_exception_wrapper(java_call_t f, JavaValue* value, methodHandle* method, JavaCallArguments* args, Thread* thread);
719
720 // On Windows this will create an actual minidump, on Linux/Solaris it will simply check core dump limits
721 static void check_or_create_dump(void* exceptionRecord, void* contextRecord, char* buffer, size_t bufferSize);
722
723 // Get the default path to the core file
724 // Returns the length of the string
725 static int get_core_path(char* buffer, size_t bufferSize);
726
727 // JVMTI & JVM monitoring and management support
728 // The thread_cpu_time() and current_thread_cpu_time() are only
729 // supported if is_thread_cpu_time_supported() returns true.
730 // They are not supported on Solaris T1.
731
732 // Thread CPU Time - return the fast estimate on a platform
733 // On Solaris - call gethrvtime (fast) - user time only
734 // On Linux - fast clock_gettime where available - user+sys
735 // - otherwise: very slow /proc fs - user+sys
736 // On Windows - GetThreadTimes - user+sys
737 static jlong current_thread_cpu_time();
738 static jlong thread_cpu_time(Thread* t);
739
740 // Thread CPU Time with user_sys_cpu_time parameter.
741 //
742 // If user_sys_cpu_time is true, user+sys time is returned.
743 // Otherwise, only user time is returned
744 static jlong current_thread_cpu_time(bool user_sys_cpu_time);
745 static jlong thread_cpu_time(Thread* t, bool user_sys_cpu_time);
746
747 // Return a bunch of info about the timers.
748 // Note that the returned info for these two functions may be different
749 // on some platforms
750 static void current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr);
751 static void thread_cpu_time_info(jvmtiTimerInfo *info_ptr);
752
753 static bool is_thread_cpu_time_supported();
754
755 // System loadavg support. Returns -1 if load average cannot be obtained.
756 static int loadavg(double loadavg[], int nelem);
757
758 // Hook for os specific jvm options that we don't want to abort on seeing
759 static bool obsolete_option(const JavaVMOption *option);
760
761 // Extensions
762 #include "runtime/os_ext.hpp"
763
764 public:
765 class CrashProtectionCallback : public StackObj {
766 public:
767 virtual void call() = 0;
768 };
769
770 // Platform dependent stuff
771 #ifdef TARGET_OS_FAMILY_linux
772 # include "os_linux.hpp"
773 # include "os_posix.hpp"
774 #endif
775 #ifdef TARGET_OS_FAMILY_solaris
776 # include "os_solaris.hpp"
777 # include "os_posix.hpp"
778 #endif
779 #ifdef TARGET_OS_FAMILY_windows
780 # include "os_windows.hpp"
781 #endif
782 #ifdef TARGET_OS_FAMILY_aix
783 # include "os_aix.hpp"
784 # include "os_posix.hpp"
785 #endif
786 #ifdef TARGET_OS_FAMILY_bsd
787 # include "os_posix.hpp"
788 # include "os_bsd.hpp"
789 #endif
790 #ifdef TARGET_OS_ARCH_linux_x86
791 # include "os_linux_x86.hpp"
792 #endif
793 #ifdef TARGET_OS_ARCH_linux_sparc
794 # include "os_linux_sparc.hpp"
795 #endif
796 #ifdef TARGET_OS_ARCH_linux_zero
797 # include "os_linux_zero.hpp"
798 #endif
799 #ifdef TARGET_OS_ARCH_solaris_x86
800 # include "os_solaris_x86.hpp"
801 #endif
802 #ifdef TARGET_OS_ARCH_solaris_sparc
803 # include "os_solaris_sparc.hpp"
804 #endif
805 #ifdef TARGET_OS_ARCH_windows_x86
806 # include "os_windows_x86.hpp"
807 #endif
808 #ifdef TARGET_OS_ARCH_linux_arm
809 # include "os_linux_arm.hpp"
810 #endif
811 #ifdef TARGET_OS_ARCH_linux_ppc
812 # include "os_linux_ppc.hpp"
813 #endif
814 #ifdef TARGET_OS_ARCH_aix_ppc
815 # include "os_aix_ppc.hpp"
816 #endif
817 #ifdef TARGET_OS_ARCH_bsd_x86
818 # include "os_bsd_x86.hpp"
819 #endif
820 #ifdef TARGET_OS_ARCH_bsd_zero
821 # include "os_bsd_zero.hpp"
822 #endif
823
824 public:
825 #ifndef PLATFORM_PRINT_NATIVE_STACK
826 // No platform-specific code for printing the native stack.
827 static bool platform_print_native_stack(outputStream* st, void* context,
828 char *buf, int buf_size) {
829 return false;
830 }
831 #endif
832
833 // debugging support (mostly used by debug.cpp but also fatal error handler)
834 static bool find(address pc, outputStream* st = tty); // OS specific function to make sense out of an address
835
836 static bool dont_yield(); // when true, JVM_Yield() is nop
837 static void print_statistics();
838
839 // Thread priority helpers (implemented in OS-specific part)
840 static OSReturn set_native_priority(Thread* thread, int native_prio);
841 static OSReturn get_native_priority(const Thread* const thread, int* priority_ptr);
842 static int java_to_os_priority[CriticalPriority + 1];
843 // Hint to the underlying OS that a task switch would not be good.
844 // Void return because it's a hint and can fail.
845 static void hint_no_preempt();
846
847 // Used at creation if requested by the diagnostic flag PauseAtStartup.
848 // Causes the VM to wait until an external stimulus has been applied
849 // (for Unix, that stimulus is a signal, for Windows, an external
850 // ResumeThread call)
851 static void pause();
852
853 // Builds a platform dependent Agent_OnLoad_<libname> function name
854 // which is used to find statically linked in agents.
855 static char* build_agent_function_name(const char *sym, const char *cname,
856 bool is_absolute_path);
857
858 class SuspendedThreadTaskContext {
859 public:
860 SuspendedThreadTaskContext(Thread* thread, void *ucontext) : _thread(thread), _ucontext(ucontext) {}
861 Thread* thread() const { return _thread; }
862 void* ucontext() const { return _ucontext; }
863 private:
864 Thread* _thread;
865 void* _ucontext;
866 };
867
868 class SuspendedThreadTask {
869 public:
870 SuspendedThreadTask(Thread* thread) : _thread(thread), _done(false) {}
871 virtual ~SuspendedThreadTask() {}
872 void run();
873 bool is_done() { return _done; }
874 virtual void do_task(const SuspendedThreadTaskContext& context) = 0;
875 protected:
876 private:
877 void internal_do_task();
878 Thread* _thread;
879 bool _done;
880 };
881
882 #ifndef TARGET_OS_FAMILY_windows
883 // Suspend/resume support
884 // Protocol:
885 //
886 // a thread starts in SR_RUNNING
887 //
888 // SR_RUNNING can go to
889 // * SR_SUSPEND_REQUEST when the WatcherThread wants to suspend it
890 // SR_SUSPEND_REQUEST can go to
891 // * SR_RUNNING if WatcherThread decides it waited for SR_SUSPENDED too long (timeout)
892 // * SR_SUSPENDED if the stopped thread receives the signal and switches state
893 // SR_SUSPENDED can go to
894 // * SR_WAKEUP_REQUEST when the WatcherThread has done the work and wants to resume
895 // SR_WAKEUP_REQUEST can go to
896 // * SR_RUNNING when the stopped thread receives the signal
897 // * SR_WAKEUP_REQUEST on timeout (resend the signal and try again)
898 class SuspendResume {
899 public:
900 enum State {
901 SR_RUNNING,
902 SR_SUSPEND_REQUEST,
903 SR_SUSPENDED,
904 SR_WAKEUP_REQUEST
905 };
906
907 private:
908 volatile State _state;
909
910 private:
911 /* try to switch state from state "from" to state "to"
912 * returns the state set after the method is complete
913 */
914 State switch_state(State from, State to);
915
916 public:
917 SuspendResume() : _state(SR_RUNNING) { }
918
919 State state() const { return _state; }
920
921 State request_suspend() {
922 return switch_state(SR_RUNNING, SR_SUSPEND_REQUEST);
923 }
924
925 State cancel_suspend() {
926 return switch_state(SR_SUSPEND_REQUEST, SR_RUNNING);
927 }
928
929 State suspended() {
930 return switch_state(SR_SUSPEND_REQUEST, SR_SUSPENDED);
931 }
932
933 State request_wakeup() {
934 return switch_state(SR_SUSPENDED, SR_WAKEUP_REQUEST);
935 }
936
937 State running() {
938 return switch_state(SR_WAKEUP_REQUEST, SR_RUNNING);
939 }
940
941 bool is_running() const {
942 return _state == SR_RUNNING;
943 }
944
945 bool is_suspend_request() const {
946 return _state == SR_SUSPEND_REQUEST;
947 }
948
949 bool is_suspended() const {
950 return _state == SR_SUSPENDED;
951 }
952 };
953 #endif
954
955
956 protected:
957 static long _rand_seed; // seed for random number generator
958 static int _processor_count; // number of processors
959
960 static char* format_boot_path(const char* format_string,
961 const char* home,
962 int home_len,
963 char fileSep,
964 char pathSep);
965 static bool set_boot_path(char fileSep, char pathSep);
966 static char** split_path(const char* path, int* n);
967
968 };
969
970 // Note that "PAUSE" is almost always used with synchronization
971 // so arguably we should provide Atomic::SpinPause() instead
972 // of the global SpinPause() with C linkage.
973 // It'd also be eligible for inlining on many platforms.
974
975 extern "C" int SpinPause();
976
977 #endif // SHARE_VM_RUNTIME_OS_HPP