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 class AgentLibrary;
50
51 // os defines the interface to operating system; this includes traditional
52 // OS services (time, I/O) as well as other functionality with system-
53 // dependent code.
54
55 typedef void (*dll_func)(...);
56
57 class Thread;
58 class JavaThread;
59 class Event;
60 class DLL;
61 class FileHandle;
62 template<class E> class GrowableArray;
63
64 // %%%%% Moved ThreadState, START_FN, OSThread to new osThread.hpp. -- Rose
65
66 // Platform-independent error return values from OS functions
67 enum OSReturn {
68 OS_OK = 0, // Operation was successful
69 OS_ERR = -1, // Operation failed
70 OS_INTRPT = -2, // Operation was interrupted
71 OS_TIMEOUT = -3, // Operation timed out
72 OS_NOMEM = -5, // Operation failed for lack of memory
73 OS_NORESOURCE = -6 // Operation failed for lack of nonmemory resource
74 };
75
76 enum ThreadPriority { // JLS 20.20.1-3
77 NoPriority = -1, // Initial non-priority value
78 MinPriority = 1, // Minimum priority
79 NormPriority = 5, // Normal (non-daemon) priority
80 NearMaxPriority = 9, // High priority, used for VMThread
81 MaxPriority = 10, // Highest priority, used for WatcherThread
82 // ensures that VMThread doesn't starve profiler
83 CriticalPriority = 11 // Critical thread priority
84 };
85
86 // Executable parameter flag for os::commit_memory() and
87 // os::commit_memory_or_exit().
88 const bool ExecMem = true;
89
90 // Typedef for structured exception handling support
91 typedef void (*java_call_t)(JavaValue* value, methodHandle* method, JavaCallArguments* args, Thread* thread);
92
93 class os: AllStatic {
94 public:
95 enum { page_sizes_max = 9 }; // Size of _page_sizes array (8 plus a sentinel)
96
97 private:
98 static OSThread* _starting_thread;
99 static address _polling_page;
100 static volatile int32_t * _mem_serialize_page;
101 static uintptr_t _serialize_page_mask;
102 public:
103 static size_t _page_sizes[page_sizes_max];
104
105 private:
106 static void init_page_sizes(size_t default_page_size) {
107 _page_sizes[0] = default_page_size;
108 _page_sizes[1] = 0; // sentinel
109 }
110
111 static char* pd_reserve_memory(size_t bytes, char* addr = 0,
112 size_t alignment_hint = 0);
113 static char* pd_attempt_reserve_memory_at(size_t bytes, char* addr);
114 static void pd_split_reserved_memory(char *base, size_t size,
115 size_t split, bool realloc);
116 static bool pd_commit_memory(char* addr, size_t bytes, bool executable);
117 static bool pd_commit_memory(char* addr, size_t size, size_t alignment_hint,
118 bool executable);
119 // Same as pd_commit_memory() that either succeeds or calls
120 // vm_exit_out_of_memory() with the specified mesg.
121 static void pd_commit_memory_or_exit(char* addr, size_t bytes,
122 bool executable, const char* mesg);
123 static void pd_commit_memory_or_exit(char* addr, size_t size,
124 size_t alignment_hint,
125 bool executable, const char* mesg);
126 static bool pd_uncommit_memory(char* addr, size_t bytes);
127 static bool pd_release_memory(char* addr, size_t bytes);
128
129 static char* pd_map_memory(int fd, const char* file_name, size_t file_offset,
130 char *addr, size_t bytes, bool read_only = false,
131 bool allow_exec = false);
132 static char* pd_remap_memory(int fd, const char* file_name, size_t file_offset,
133 char *addr, size_t bytes, bool read_only,
134 bool allow_exec);
135 static bool pd_unmap_memory(char *addr, size_t bytes);
136 static void pd_free_memory(char *addr, size_t bytes, size_t alignment_hint);
137 static void pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint);
138
139
140 public:
141 static void init(void); // Called before command line parsing
142 static jint init_2(void); // Called after command line parsing
143 static void init_globals(void) { // Called from init_globals() in init.cpp
144 init_globals_ext();
145 }
146 static void init_3(void); // Called at the end of vm init
147
148 // File names are case-insensitive on windows only
149 // Override me as needed
150 static int file_name_strcmp(const char* s1, const char* s2);
151
152 static bool getenv(const char* name, char* buffer, int len);
153 static bool have_special_privileges();
154
155 static jlong javaTimeMillis();
156 static jlong javaTimeNanos();
157 static void javaTimeNanos_info(jvmtiTimerInfo *info_ptr);
158 static void run_periodic_checks();
159
160
161 // Returns the elapsed time in seconds since the vm started.
162 static double elapsedTime();
163
164 // Returns real time in seconds since an arbitrary point
165 // in the past.
166 static bool getTimesSecs(double* process_real_time,
167 double* process_user_time,
168 double* process_system_time);
169
170 // Interface to the performance counter
171 static jlong elapsed_counter();
172 static jlong elapsed_frequency();
173
174 // The "virtual time" of a thread is the amount of time a thread has
175 // actually run. The first function indicates whether the OS supports
176 // this functionality for the current thread, and if so:
177 // * the second enables vtime tracking (if that is required).
178 // * the third tells whether vtime is enabled.
179 // * the fourth returns the elapsed virtual time for the current
180 // thread.
181 static bool supports_vtime();
182 static bool enable_vtime();
183 static bool vtime_enabled();
184 static double elapsedVTime();
185
186 // Return current local time in a string (YYYY-MM-DD HH:MM:SS).
187 // It is MT safe, but not async-safe, as reading time zone
188 // information may require a lock on some platforms.
189 static char* local_time_string(char *buf, size_t buflen);
190 static struct tm* localtime_pd (const time_t* clock, struct tm* res);
191 // Fill in buffer with current local time as an ISO-8601 string.
192 // E.g., YYYY-MM-DDThh:mm:ss.mmm+zzzz.
193 // Returns buffer, or NULL if it failed.
194 static char* iso8601_time(char* buffer, size_t buffer_length);
195
196 // Interface for detecting multiprocessor system
197 static inline bool is_MP() {
198 assert(_processor_count > 0, "invalid processor count");
199 return _processor_count > 1 || AssumeMP;
200 }
201 static julong available_memory();
202 static julong physical_memory();
203 static bool has_allocatable_memory_limit(julong* limit);
204 static bool is_server_class_machine();
205
206 // number of CPUs
207 static int processor_count() {
208 return _processor_count;
209 }
210 static void set_processor_count(int count) { _processor_count = count; }
211
212 // Returns the number of CPUs this process is currently allowed to run on.
213 // Note that on some OSes this can change dynamically.
214 static int active_processor_count();
215
216 // Bind processes to processors.
217 // This is a two step procedure:
218 // first you generate a distribution of processes to processors,
219 // then you bind processes according to that distribution.
220 // Compute a distribution for number of processes to processors.
221 // Stores the processor id's into the distribution array argument.
222 // Returns true if it worked, false if it didn't.
223 static bool distribute_processes(uint length, uint* distribution);
224 // Binds the current process to a processor.
225 // Returns true if it worked, false if it didn't.
226 static bool bind_to_processor(uint processor_id);
227
228 // Give a name to the current thread.
229 static void set_native_thread_name(const char *name);
230
231 // Interface for stack banging (predetect possible stack overflow for
232 // exception processing) There are guard pages, and above that shadow
233 // pages for stack overflow checking.
234 static bool uses_stack_guard_pages();
235 static bool allocate_stack_guard_pages();
236 static void bang_stack_shadow_pages();
237 static bool stack_shadow_pages_available(Thread *thread, methodHandle method);
238
239 // OS interface to Virtual Memory
240
241 // Return the default page size.
242 static int vm_page_size();
243
244 // Return the page size to use for a region of memory. The min_pages argument
245 // is a hint intended to limit fragmentation; it says the returned page size
246 // should be <= region_max_size / min_pages. Because min_pages is a hint,
247 // this routine may return a size larger than region_max_size / min_pages.
248 //
249 // The current implementation ignores min_pages if a larger page size is an
250 // exact multiple of both region_min_size and region_max_size. This allows
251 // larger pages to be used when doing so would not cause fragmentation; in
252 // particular, a single page can be used when region_min_size ==
253 // region_max_size == a supported page size.
254 static size_t page_size_for_region(size_t region_min_size,
255 size_t region_max_size,
256 uint min_pages);
257
258 // Methods for tracing page sizes returned by the above method; enabled by
259 // TracePageSizes. The region_{min,max}_size parameters should be the values
260 // passed to page_size_for_region() and page_size should be the result of that
261 // call. The (optional) base and size parameters should come from the
262 // ReservedSpace base() and size() methods.
263 static void trace_page_sizes(const char* str, const size_t* page_sizes,
264 int count) PRODUCT_RETURN;
265 static void trace_page_sizes(const char* str, const size_t region_min_size,
266 const size_t region_max_size,
267 const size_t page_size,
268 const char* base = NULL,
269 const size_t size = 0) PRODUCT_RETURN;
270
271 static int vm_allocation_granularity();
272 static char* reserve_memory(size_t bytes, char* addr = 0,
273 size_t alignment_hint = 0);
274 static char* reserve_memory(size_t bytes, char* addr,
275 size_t alignment_hint, MEMFLAGS flags);
276 static char* reserve_memory_aligned(size_t size, size_t alignment);
277 static char* attempt_reserve_memory_at(size_t bytes, char* addr);
278 static void split_reserved_memory(char *base, size_t size,
279 size_t split, bool realloc);
280 static bool commit_memory(char* addr, size_t bytes, bool executable);
281 static bool commit_memory(char* addr, size_t size, size_t alignment_hint,
282 bool executable);
283 // Same as commit_memory() that either succeeds or calls
284 // vm_exit_out_of_memory() with the specified mesg.
285 static void commit_memory_or_exit(char* addr, size_t bytes,
286 bool executable, const char* mesg);
287 static void commit_memory_or_exit(char* addr, size_t size,
288 size_t alignment_hint,
289 bool executable, const char* mesg);
290 static bool uncommit_memory(char* addr, size_t bytes);
291 static bool release_memory(char* addr, size_t bytes);
292
293 enum ProtType { MEM_PROT_NONE, MEM_PROT_READ, MEM_PROT_RW, MEM_PROT_RWX };
294 static bool protect_memory(char* addr, size_t bytes, ProtType prot,
295 bool is_committed = true);
296
297 static bool guard_memory(char* addr, size_t bytes);
298 static bool unguard_memory(char* addr, size_t bytes);
299 static bool create_stack_guard_pages(char* addr, size_t bytes);
300 static bool pd_create_stack_guard_pages(char* addr, size_t bytes);
301 static bool remove_stack_guard_pages(char* addr, size_t bytes);
302
303 static char* map_memory(int fd, const char* file_name, size_t file_offset,
304 char *addr, size_t bytes, bool read_only = false,
305 bool allow_exec = false);
306 static char* remap_memory(int fd, const char* file_name, size_t file_offset,
307 char *addr, size_t bytes, bool read_only,
308 bool allow_exec);
309 static bool unmap_memory(char *addr, size_t bytes);
310 static void free_memory(char *addr, size_t bytes, size_t alignment_hint);
311 static void realign_memory(char *addr, size_t bytes, size_t alignment_hint);
312
313 // NUMA-specific interface
314 static bool numa_has_static_binding();
315 static bool numa_has_group_homing();
316 static void numa_make_local(char *addr, size_t bytes, int lgrp_hint);
317 static void numa_make_global(char *addr, size_t bytes);
318 static size_t numa_get_groups_num();
319 static size_t numa_get_leaf_groups(int *ids, size_t size);
320 static bool numa_topology_changed();
321 static int numa_get_group_id();
322
323 // Page manipulation
324 struct page_info {
325 size_t size;
326 int lgrp_id;
327 };
328 static bool get_page_info(char *start, page_info* info);
329 static char* scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found);
330
331 static char* non_memory_address_word();
332 // reserve, commit and pin the entire memory region
333 static char* reserve_memory_special(size_t size, size_t alignment,
334 char* addr, bool executable);
335 static bool release_memory_special(char* addr, size_t bytes);
336 static void large_page_init();
337 static size_t large_page_size();
338 static bool can_commit_large_page_memory();
339 static bool can_execute_large_page_memory();
340
341 // OS interface to polling page
342 static address get_polling_page() { return _polling_page; }
343 static void set_polling_page(address page) { _polling_page = page; }
344 static bool is_poll_address(address addr) { return addr >= _polling_page && addr < (_polling_page + os::vm_page_size()); }
345 static void make_polling_page_unreadable();
346 static void make_polling_page_readable();
347
348 // Routines used to serialize the thread state without using membars
349 static void serialize_thread_states();
350
351 // Since we write to the serialize page from every thread, we
352 // want stores to be on unique cache lines whenever possible
353 // in order to minimize CPU cross talk. We pre-compute the
354 // amount to shift the thread* to make this offset unique to
355 // each thread.
356 static int get_serialize_page_shift_count() {
357 return SerializePageShiftCount;
358 }
359
360 static void set_serialize_page_mask(uintptr_t mask) {
361 _serialize_page_mask = mask;
362 }
363
364 static unsigned int get_serialize_page_mask() {
365 return _serialize_page_mask;
366 }
367
368 static void set_memory_serialize_page(address page);
369
370 static address get_memory_serialize_page() {
371 return (address)_mem_serialize_page;
372 }
373
374 static inline void write_memory_serialize_page(JavaThread *thread) {
375 uintptr_t page_offset = ((uintptr_t)thread >>
376 get_serialize_page_shift_count()) &
377 get_serialize_page_mask();
378 *(volatile int32_t *)((uintptr_t)_mem_serialize_page+page_offset) = 1;
379 }
380
381 static bool is_memory_serialize_page(JavaThread *thread, address addr) {
382 if (UseMembar) return false;
383 // Previously this function calculated the exact address of this
384 // thread's serialize page, and checked if the faulting address
385 // was equal. However, some platforms mask off faulting addresses
386 // to the page size, so now we just check that the address is
387 // within the page. This makes the thread argument unnecessary,
388 // but we retain the NULL check to preserve existing behaviour.
389 if (thread == NULL) return false;
390 address page = (address) _mem_serialize_page;
391 return addr >= page && addr < (page + os::vm_page_size());
392 }
393
394 static void block_on_serialize_page_trap();
395
396 // threads
397
398 enum ThreadType {
399 vm_thread,
400 cgc_thread, // Concurrent GC thread
401 pgc_thread, // Parallel GC thread
402 java_thread,
403 compiler_thread,
404 watcher_thread,
405 os_thread
406 };
407
408 static bool create_thread(Thread* thread,
409 ThreadType thr_type,
410 size_t stack_size = 0);
411 static bool create_main_thread(JavaThread* thread);
412 static bool create_attached_thread(JavaThread* thread);
413 static void pd_start_thread(Thread* thread);
414 static void start_thread(Thread* thread);
415
416 static void initialize_thread(Thread* thr);
417 static void free_thread(OSThread* osthread);
418
419 // thread id on Linux/64bit is 64bit, on Windows and Solaris, it's 32bit
420 static intx current_thread_id();
421 static int current_process_id();
422 static int sleep(Thread* thread, jlong ms, bool interruptable);
423 static int naked_sleep();
424 static void infinite_sleep(); // never returns, use with CAUTION
425 static void yield(); // Yields to all threads with same priority
426 enum YieldResult {
427 YIELD_SWITCHED = 1, // caller descheduled, other ready threads exist & ran
428 YIELD_NONEREADY = 0, // No other runnable/ready threads.
429 // platform-specific yield return immediately
430 YIELD_UNKNOWN = -1 // Unknown: platform doesn't support _SWITCHED or _NONEREADY
431 // YIELD_SWITCHED and YIELD_NONREADY imply the platform supports a "strong"
432 // yield that can be used in lieu of blocking.
433 } ;
434 static YieldResult NakedYield () ;
435 static void yield_all(int attempts = 0); // Yields to all other threads including lower priority
436 static void loop_breaker(int attempts); // called from within tight loops to possibly influence time-sharing
437 static OSReturn set_priority(Thread* thread, ThreadPriority priority);
438 static OSReturn get_priority(const Thread* const thread, ThreadPriority& priority);
439
440 static void interrupt(Thread* thread);
441 static bool is_interrupted(Thread* thread, bool clear_interrupted);
442
443 static int pd_self_suspend_thread(Thread* thread);
444
445 static ExtendedPC fetch_frame_from_context(void* ucVoid, intptr_t** sp, intptr_t** fp);
446 static frame fetch_frame_from_context(void* ucVoid);
447
448 static ExtendedPC get_thread_pc(Thread *thread);
449 static void breakpoint();
450
451 static address current_stack_pointer();
452 static address current_stack_base();
453 static size_t current_stack_size();
454
455 static void verify_stack_alignment() PRODUCT_RETURN;
456
457 static int message_box(const char* title, const char* message);
458 static char* do_you_want_to_debug(const char* message);
459
460 // run cmd in a separate process and return its exit code; or -1 on failures
461 static int fork_and_exec(char *cmd);
462
463 // Set file to send error reports.
464 static void set_error_file(const char *logfile);
465
466 // os::exit() is merged with vm_exit()
467 // static void exit(int num);
468
469 // Terminate the VM, but don't exit the process
470 static void shutdown();
471
472 // Terminate with an error. Default is to generate a core file on platforms
473 // that support such things. This calls shutdown() and then aborts.
474 static void abort(bool dump_core = true);
475
476 // Die immediately, no exit hook, no abort hook, no cleanup.
477 static void die();
478
479 // File i/o operations
480 static const int default_file_open_flags();
481 static int open(const char *path, int oflag, int mode);
482 static FILE* open(int fd, const char* mode);
483 static int close(int fd);
484 static jlong lseek(int fd, jlong offset, int whence);
485 static char* native_path(char *path);
486 static int ftruncate(int fd, jlong length);
487 static int fsync(int fd);
488 static int available(int fd, jlong *bytes);
489
490 //File i/o operations
491
492 static size_t read(int fd, void *buf, unsigned int nBytes);
493 static size_t restartable_read(int fd, void *buf, unsigned int nBytes);
494 static size_t write(int fd, const void *buf, unsigned int nBytes);
495
496 // Reading directories.
497 static DIR* opendir(const char* dirname);
498 static int readdir_buf_size(const char *path);
499 static struct dirent* readdir(DIR* dirp, dirent* dbuf);
500 static int closedir(DIR* dirp);
501
502 // Dynamic library extension
503 static const char* dll_file_extension();
504
505 static const char* get_temp_directory();
506 static const char* get_current_directory(char *buf, size_t buflen);
507
508 // Builds a platform-specific full library path given a ld path and lib name
509 // Returns true if buffer contains full path to existing file, false otherwise
510 static bool dll_build_name(char* buffer, size_t size,
511 const char* pathname, const char* fname);
512
513 // Symbol lookup, find nearest function name; basically it implements
514 // dladdr() for all platforms. Name of the nearest function is copied
515 // to buf. Distance from its base address is optionally returned as offset.
516 // If function name is not found, buf[0] is set to '\0' and offset is
517 // set to -1 (if offset is non-NULL).
518 static bool dll_address_to_function_name(address addr, char* buf,
519 int buflen, int* offset);
520
521 // Locate DLL/DSO. On success, full path of the library is copied to
522 // buf, and offset is optionally set to be the distance between addr
523 // and the library's base address. On failure, buf[0] is set to '\0'
524 // and offset is set to -1 (if offset is non-NULL).
525 static bool dll_address_to_library_name(address addr, char* buf,
526 int buflen, int* offset);
527
528 // Find out whether the pc is in the static code for jvm.dll/libjvm.so.
529 static bool address_is_in_vm(address addr);
530
531 // Loads .dll/.so and
532 // in case of error it checks if .dll/.so was built for the
533 // same architecture as Hotspot is running on
534 static void* dll_load(const char *name, char *ebuf, int ebuflen);
535
536 // lookup symbol in a shared library
537 static void* dll_lookup(void* handle, const char* name);
538
539 // Unload library
540 static void dll_unload(void *lib);
541
542 // Return the handle of this process
543 static void* get_default_process_handle();
544
545 // Check for static linked agent library
546 static bool find_builtin_agent(AgentLibrary *agent_lib, const char *syms[],
547 size_t syms_len);
548
549 // Find agent entry point
550 static void *find_agent_function(AgentLibrary *agent_lib, bool check_lib,
551 const char *syms[], size_t syms_len);
552
553 // Print out system information; they are called by fatal error handler.
554 // Output format may be different on different platforms.
555 static void print_os_info(outputStream* st);
556 static void print_os_info_brief(outputStream* st);
557 static void print_cpu_info(outputStream* st);
558 static void pd_print_cpu_info(outputStream* st);
559 static void print_memory_info(outputStream* st);
560 static void print_dll_info(outputStream* st);
561 static void print_environment_variables(outputStream* st, const char** env_list, char* buffer, int len);
562 static void print_context(outputStream* st, void* context);
563 static void print_register_info(outputStream* st, void* context);
564 static void print_siginfo(outputStream* st, void* siginfo);
565 static void print_signal_handlers(outputStream* st, char* buf, size_t buflen);
566 static void print_date_and_time(outputStream* st);
567
568 static void print_location(outputStream* st, intptr_t x, bool verbose = false);
569 static size_t lasterror(char *buf, size_t len);
570 static int get_last_error();
571
572 // Determines whether the calling process is being debugged by a user-mode debugger.
573 static bool is_debugger_attached();
574
575 // wait for a key press if PauseAtExit is set
576 static void wait_for_keypress_at_exit(void);
577
578 // The following two functions are used by fatal error handler to trace
579 // native (C) frames. They are not part of frame.hpp/frame.cpp because
580 // frame.hpp/cpp assume thread is JavaThread, and also because different
581 // OS/compiler may have different convention or provide different API to
582 // walk C frames.
583 //
584 // We don't attempt to become a debugger, so we only follow frames if that
585 // does not require a lookup in the unwind table, which is part of the binary
586 // file but may be unsafe to read after a fatal error. So on x86, we can
587 // only walk stack if %ebp is used as frame pointer; on ia64, it's not
588 // possible to walk C stack without having the unwind table.
589 static bool is_first_C_frame(frame *fr);
590 static frame get_sender_for_C_frame(frame *fr);
591
592 // return current frame. pc() and sp() are set to NULL on failure.
593 static frame current_frame();
594
595 static void print_hex_dump(outputStream* st, address start, address end, int unitsize);
596
597 // returns a string to describe the exception/signal;
598 // returns NULL if exception_code is not an OS exception/signal.
599 static const char* exception_name(int exception_code, char* buf, size_t buflen);
600
601 // Returns native Java library, loads if necessary
602 static void* native_java_library();
603
604 // Fills in path to jvm.dll/libjvm.so (used by the Disassembler)
605 static void jvm_path(char *buf, jint buflen);
606
607 // Returns true if we are running in a headless jre.
608 static bool is_headless_jre();
609
610 // JNI names
611 static void print_jni_name_prefix_on(outputStream* st, int args_size);
612 static void print_jni_name_suffix_on(outputStream* st, int args_size);
613
614 // File conventions
615 static const char* file_separator();
616 static const char* line_separator();
617 static const char* path_separator();
618
619 // Init os specific system properties values
620 static void init_system_properties_values();
621
622 // IO operations, non-JVM_ version.
623 static int stat(const char* path, struct stat* sbuf);
624 static bool dir_is_empty(const char* path);
625
626 // IO operations on binary files
627 static int create_binary_file(const char* path, bool rewrite_existing);
628 static jlong current_file_offset(int fd);
629 static jlong seek_to_file_offset(int fd, jlong offset);
630
631 // Thread Local Storage
632 static int allocate_thread_local_storage();
633 static void thread_local_storage_at_put(int index, void* value);
634 static void* thread_local_storage_at(int index);
635 static void free_thread_local_storage(int index);
636
637 // Stack walk
638 static address get_caller_pc(int n = 0);
639
640 // General allocation (must be MT-safe)
641 static void* malloc (size_t size, MEMFLAGS flags, address caller_pc = 0);
642 static void* realloc (void *memblock, size_t size, MEMFLAGS flags, address caller_pc = 0);
643 static void free (void *memblock, MEMFLAGS flags = mtNone);
644 static bool check_heap(bool force = false); // verify C heap integrity
645 static char* strdup(const char *, MEMFLAGS flags = mtInternal); // Like strdup
646
647 #ifndef PRODUCT
648 static julong num_mallocs; // # of calls to malloc/realloc
649 static julong alloc_bytes; // # of bytes allocated
650 static julong num_frees; // # of calls to free
651 static julong free_bytes; // # of bytes freed
652 #endif
653
654 // SocketInterface (ex HPI SocketInterface )
655 static int socket(int domain, int type, int protocol);
656 static int socket_close(int fd);
657 static int socket_shutdown(int fd, int howto);
658 static int recv(int fd, char* buf, size_t nBytes, uint flags);
659 static int send(int fd, char* buf, size_t nBytes, uint flags);
660 static int raw_send(int fd, char* buf, size_t nBytes, uint flags);
661 static int timeout(int fd, long timeout);
662 static int listen(int fd, int count);
663 static int connect(int fd, struct sockaddr* him, socklen_t len);
664 static int bind(int fd, struct sockaddr* him, socklen_t len);
665 static int accept(int fd, struct sockaddr* him, socklen_t* len);
666 static int recvfrom(int fd, char* buf, size_t nbytes, uint flags,
667 struct sockaddr* from, socklen_t* fromlen);
668 static int get_sock_name(int fd, struct sockaddr* him, socklen_t* len);
669 static int sendto(int fd, char* buf, size_t len, uint flags,
670 struct sockaddr* to, socklen_t tolen);
671 static int socket_available(int fd, jint* pbytes);
672
673 static int get_sock_opt(int fd, int level, int optname,
674 char* optval, socklen_t* optlen);
675 static int set_sock_opt(int fd, int level, int optname,
676 const char* optval, socklen_t optlen);
677 static int get_host_name(char* name, int namelen);
678
679 static struct hostent* get_host_by_name(char* name);
680
681 // Support for signals (see JVM_RaiseSignal, JVM_RegisterSignal)
682 static void signal_init();
683 static void signal_init_pd();
684 static void signal_notify(int signal_number);
685 static void* signal(int signal_number, void* handler);
686 static void signal_raise(int signal_number);
687 static int signal_wait();
688 static int signal_lookup();
689 static void* user_handler();
690 static void terminate_signal_thread();
691 static int sigexitnum_pd();
692
693 // random number generation
694 static long random(); // return 32bit pseudorandom number
695 static void init_random(long initval); // initialize random sequence
696
697 // Structured OS Exception support
698 static void os_exception_wrapper(java_call_t f, JavaValue* value, methodHandle* method, JavaCallArguments* args, Thread* thread);
699
700 // On Windows this will create an actual minidump, on Linux/Solaris it will simply check core dump limits
701 static void check_or_create_dump(void* exceptionRecord, void* contextRecord, char* buffer, size_t bufferSize);
702
703 // Get the default path to the core file
704 // Returns the length of the string
705 static int get_core_path(char* buffer, size_t bufferSize);
706
707 // JVMTI & JVM monitoring and management support
708 // The thread_cpu_time() and current_thread_cpu_time() are only
709 // supported if is_thread_cpu_time_supported() returns true.
710 // They are not supported on Solaris T1.
711
712 // Thread CPU Time - return the fast estimate on a platform
713 // On Solaris - call gethrvtime (fast) - user time only
714 // On Linux - fast clock_gettime where available - user+sys
715 // - otherwise: very slow /proc fs - user+sys
716 // On Windows - GetThreadTimes - user+sys
717 static jlong current_thread_cpu_time();
718 static jlong thread_cpu_time(Thread* t);
719
720 // Thread CPU Time with user_sys_cpu_time parameter.
721 //
722 // If user_sys_cpu_time is true, user+sys time is returned.
723 // Otherwise, only user time is returned
724 static jlong current_thread_cpu_time(bool user_sys_cpu_time);
725 static jlong thread_cpu_time(Thread* t, bool user_sys_cpu_time);
726
727 // Return a bunch of info about the timers.
728 // Note that the returned info for these two functions may be different
729 // on some platforms
730 static void current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr);
731 static void thread_cpu_time_info(jvmtiTimerInfo *info_ptr);
732
733 static bool is_thread_cpu_time_supported();
734
735 // System loadavg support. Returns -1 if load average cannot be obtained.
736 static int loadavg(double loadavg[], int nelem);
737
738 // Hook for os specific jvm options that we don't want to abort on seeing
739 static bool obsolete_option(const JavaVMOption *option);
740
741 // Extensions
742 #include "runtime/os_ext.hpp"
743
744 public:
745 class CrashProtectionCallback : public StackObj {
746 public:
747 virtual void call() = 0;
748 };
749
750 // Platform dependent stuff
751 #ifdef TARGET_OS_FAMILY_linux
752 # include "os_linux.hpp"
753 # include "os_posix.hpp"
754 #endif
755 #ifdef TARGET_OS_FAMILY_solaris
756 # include "os_solaris.hpp"
757 # include "os_posix.hpp"
758 #endif
759 #ifdef TARGET_OS_FAMILY_windows
760 # include "os_windows.hpp"
761 #endif
762 #ifdef TARGET_OS_FAMILY_bsd
763 # include "os_posix.hpp"
764 # include "os_bsd.hpp"
765 #endif
766 #ifdef TARGET_OS_ARCH_linux_x86
767 # include "os_linux_x86.hpp"
768 #endif
769 #ifdef TARGET_OS_ARCH_linux_sparc
770 # include "os_linux_sparc.hpp"
771 #endif
772 #ifdef TARGET_OS_ARCH_linux_zero
773 # include "os_linux_zero.hpp"
774 #endif
775 #ifdef TARGET_OS_ARCH_solaris_x86
776 # include "os_solaris_x86.hpp"
777 #endif
778 #ifdef TARGET_OS_ARCH_solaris_sparc
779 # include "os_solaris_sparc.hpp"
780 #endif
781 #ifdef TARGET_OS_ARCH_windows_x86
782 # include "os_windows_x86.hpp"
783 #endif
784 #ifdef TARGET_OS_ARCH_linux_arm
785 # include "os_linux_arm.hpp"
786 #endif
787 #ifdef TARGET_OS_ARCH_linux_ppc
788 # include "os_linux_ppc.hpp"
789 #endif
790 #ifdef TARGET_OS_ARCH_bsd_x86
791 # include "os_bsd_x86.hpp"
792 #endif
793 #ifdef TARGET_OS_ARCH_bsd_zero
794 # include "os_bsd_zero.hpp"
795 #endif
796
797 public:
798 // debugging support (mostly used by debug.cpp but also fatal error handler)
799 static bool find(address pc, outputStream* st = tty); // OS specific function to make sense out of an address
800
801 static bool dont_yield(); // when true, JVM_Yield() is nop
802 static void print_statistics();
803
804 // Thread priority helpers (implemented in OS-specific part)
805 static OSReturn set_native_priority(Thread* thread, int native_prio);
806 static OSReturn get_native_priority(const Thread* const thread, int* priority_ptr);
807 static int java_to_os_priority[CriticalPriority + 1];
808 // Hint to the underlying OS that a task switch would not be good.
809 // Void return because it's a hint and can fail.
810 static void hint_no_preempt();
811
812 // Used at creation if requested by the diagnostic flag PauseAtStartup.
813 // Causes the VM to wait until an external stimulus has been applied
814 // (for Unix, that stimulus is a signal, for Windows, an external
815 // ResumeThread call)
816 static void pause();
817
818 // Builds a platform dependent Agent_OnLoad_<libname> function name
819 // which is used to find statically linked in agents.
820 static char* build_agent_function_name(const char *sym, const char *cname,
821 bool is_absolute_path);
822
823 class SuspendedThreadTaskContext {
824 public:
825 SuspendedThreadTaskContext(Thread* thread, void *ucontext) : _thread(thread), _ucontext(ucontext) {}
826 Thread* thread() const { return _thread; }
827 void* ucontext() const { return _ucontext; }
828 private:
829 Thread* _thread;
830 void* _ucontext;
831 };
832
833 class SuspendedThreadTask {
834 public:
835 SuspendedThreadTask(Thread* thread) : _thread(thread), _done(false) {}
836 virtual ~SuspendedThreadTask() {}
837 void run();
838 bool is_done() { return _done; }
839 virtual void do_task(const SuspendedThreadTaskContext& context) = 0;
840 protected:
841 private:
842 void internal_do_task();
843 Thread* _thread;
844 bool _done;
845 };
846
847 #ifndef TARGET_OS_FAMILY_windows
848 // Suspend/resume support
849 // Protocol:
850 //
851 // a thread starts in SR_RUNNING
852 //
853 // SR_RUNNING can go to
854 // * SR_SUSPEND_REQUEST when the WatcherThread wants to suspend it
855 // SR_SUSPEND_REQUEST can go to
856 // * SR_RUNNING if WatcherThread decides it waited for SR_SUSPENDED too long (timeout)
857 // * SR_SUSPENDED if the stopped thread receives the signal and switches state
858 // SR_SUSPENDED can go to
859 // * SR_WAKEUP_REQUEST when the WatcherThread has done the work and wants to resume
860 // SR_WAKEUP_REQUEST can go to
861 // * SR_RUNNING when the stopped thread receives the signal
862 // * SR_WAKEUP_REQUEST on timeout (resend the signal and try again)
863 class SuspendResume {
864 public:
865 enum State {
866 SR_RUNNING,
867 SR_SUSPEND_REQUEST,
868 SR_SUSPENDED,
869 SR_WAKEUP_REQUEST
870 };
871
872 private:
873 volatile State _state;
874
875 private:
876 /* try to switch state from state "from" to state "to"
877 * returns the state set after the method is complete
878 */
879 State switch_state(State from, State to);
880
881 public:
882 SuspendResume() : _state(SR_RUNNING) { }
883
884 State state() const { return _state; }
885
886 State request_suspend() {
887 return switch_state(SR_RUNNING, SR_SUSPEND_REQUEST);
888 }
889
890 State cancel_suspend() {
891 return switch_state(SR_SUSPEND_REQUEST, SR_RUNNING);
892 }
893
894 State suspended() {
895 return switch_state(SR_SUSPEND_REQUEST, SR_SUSPENDED);
896 }
897
898 State request_wakeup() {
899 return switch_state(SR_SUSPENDED, SR_WAKEUP_REQUEST);
900 }
901
902 State running() {
903 return switch_state(SR_WAKEUP_REQUEST, SR_RUNNING);
904 }
905
906 bool is_running() const {
907 return _state == SR_RUNNING;
908 }
909
910 bool is_suspend_request() const {
911 return _state == SR_SUSPEND_REQUEST;
912 }
913
914 bool is_suspended() const {
915 return _state == SR_SUSPENDED;
916 }
917 };
918 #endif
919
920
921 protected:
922 static long _rand_seed; // seed for random number generator
923 static int _processor_count; // number of processors
924
925 static char* format_boot_path(const char* format_string,
926 const char* home,
927 int home_len,
928 char fileSep,
929 char pathSep);
930 static bool set_boot_path(char fileSep, char pathSep);
931 static char** split_path(const char* path, int* n);
932
933 };
934
935 // Note that "PAUSE" is almost always used with synchronization
936 // so arguably we should provide Atomic::SpinPause() instead
937 // of the global SpinPause() with C linkage.
938 // It'd also be eligible for inlining on many platforms.
939
940 extern "C" int SpinPause();
941
942 #endif // SHARE_VM_RUNTIME_OS_HPP