1 /*
2 * Copyright (c) 1997, 2015, 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/extendedPC.hpp"
30 #include "runtime/handles.hpp"
31 #include "utilities/top.hpp"
32 #ifdef TARGET_OS_FAMILY_linux
33 # include "jvm_linux.h"
34 # include <setjmp.h>
35 #endif
36 #ifdef TARGET_OS_FAMILY_solaris
37 # include "jvm_solaris.h"
38 # include <setjmp.h>
39 #endif
40 #ifdef TARGET_OS_FAMILY_windows
41 # include "jvm_windows.h"
42 #endif
43 #ifdef TARGET_OS_FAMILY_aix
44 # include "jvm_aix.h"
45 # include <setjmp.h>
46 #endif
47 #ifdef TARGET_OS_FAMILY_bsd
48 # include "jvm_bsd.h"
49 # include <setjmp.h>
50 # ifdef __APPLE__
51 # include <mach/mach_time.h>
52 # endif
53 #endif
54
55 class AgentLibrary;
56
57 // os defines the interface to operating system; this includes traditional
58 // OS services (time, I/O) as well as other functionality with system-
59 // dependent code.
60
61 typedef void (*dll_func)(...);
62
63 class Thread;
64 class JavaThread;
65 class Event;
66 class DLL;
67 class FileHandle;
68 class NativeCallStack;
69
70 template<class E> class GrowableArray;
71
72 // %%%%% Moved ThreadState, START_FN, OSThread to new osThread.hpp. -- Rose
73
74 // Platform-independent error return values from OS functions
75 enum OSReturn {
76 OS_OK = 0, // Operation was successful
77 OS_ERR = -1, // Operation failed
78 OS_INTRPT = -2, // Operation was interrupted
79 OS_TIMEOUT = -3, // Operation timed out
80 OS_NOMEM = -5, // Operation failed for lack of memory
81 OS_NORESOURCE = -6 // Operation failed for lack of nonmemory resource
82 };
83
84 enum ThreadPriority { // JLS 20.20.1-3
85 NoPriority = -1, // Initial non-priority value
86 MinPriority = 1, // Minimum priority
87 NormPriority = 5, // Normal (non-daemon) priority
88 NearMaxPriority = 9, // High priority, used for VMThread
89 MaxPriority = 10, // Highest priority, used for WatcherThread
90 // ensures that VMThread doesn't starve profiler
91 CriticalPriority = 11 // Critical thread priority
92 };
93
94 // Executable parameter flag for os::commit_memory() and
95 // os::commit_memory_or_exit().
96 const bool ExecMem = true;
97
98 // Typedef for structured exception handling support
99 typedef void (*java_call_t)(JavaValue* value, methodHandle* method, JavaCallArguments* args, Thread* thread);
100
101 class MallocTracker;
102
103 class os: AllStatic {
104 friend class VMStructs;
105 friend class MallocTracker;
106 public:
107 enum { page_sizes_max = 9 }; // Size of _page_sizes array (8 plus a sentinel)
108
109 private:
110 static OSThread* _starting_thread;
111 static address _polling_page;
112 static volatile int32_t * _mem_serialize_page;
113 static uintptr_t _serialize_page_mask;
114 public:
115 static size_t _page_sizes[page_sizes_max];
116
117 private:
118 static void init_page_sizes(size_t default_page_size) {
119 _page_sizes[0] = default_page_size;
120 _page_sizes[1] = 0; // sentinel
121 }
122
123 static char* pd_reserve_memory(size_t bytes, char* addr = 0,
124 size_t alignment_hint = 0);
125 static char* pd_attempt_reserve_memory_at(size_t bytes, char* addr);
126 static void pd_split_reserved_memory(char *base, size_t size,
127 size_t split, bool realloc);
128 static bool pd_commit_memory(char* addr, size_t bytes, bool executable);
129 static bool pd_commit_memory(char* addr, size_t size, size_t alignment_hint,
130 bool executable);
131 // Same as pd_commit_memory() that either succeeds or calls
132 // vm_exit_out_of_memory() with the specified mesg.
133 static void pd_commit_memory_or_exit(char* addr, size_t bytes,
134 bool executable, const char* mesg);
135 static void pd_commit_memory_or_exit(char* addr, size_t size,
136 size_t alignment_hint,
137 bool executable, const char* mesg);
138 static bool pd_uncommit_memory(char* addr, size_t bytes);
139 static bool pd_release_memory(char* addr, size_t bytes);
140
141 static char* pd_map_memory(int fd, const char* file_name, size_t file_offset,
142 char *addr, size_t bytes, bool read_only = false,
143 bool allow_exec = false);
144 static char* pd_remap_memory(int fd, const char* file_name, size_t file_offset,
145 char *addr, size_t bytes, bool read_only,
146 bool allow_exec);
147 static bool pd_unmap_memory(char *addr, size_t bytes);
148 static void pd_free_memory(char *addr, size_t bytes, size_t alignment_hint);
149 static void pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint);
150
151 static size_t page_size_for_region(size_t region_size, size_t min_pages, bool must_be_aligned);
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 javaTimeSystemUTC(jlong &seconds, jlong &nanos);
177 static void run_periodic_checks();
178 static bool supports_monotonic_clock();
179
180 // Returns the elapsed time in seconds since the vm started.
181 static double elapsedTime();
182
183 // Returns real time in seconds since an arbitrary point
184 // in the past.
185 static bool getTimesSecs(double* process_real_time,
186 double* process_user_time,
187 double* process_system_time);
188
189 // Interface to the performance counter
190 static jlong elapsed_counter();
191 static jlong elapsed_frequency();
192
193 // The "virtual time" of a thread is the amount of time a thread has
194 // actually run. The first function indicates whether the OS supports
195 // this functionality for the current thread, and if so:
196 // * the second enables vtime tracking (if that is required).
197 // * the third tells whether vtime is enabled.
198 // * the fourth returns the elapsed virtual time for the current
199 // thread.
200 static bool supports_vtime();
201 static bool enable_vtime();
202 static bool vtime_enabled();
203 static double elapsedVTime();
204
205 // Return current local time in a string (YYYY-MM-DD HH:MM:SS).
206 // It is MT safe, but not async-safe, as reading time zone
207 // information may require a lock on some platforms.
208 static char* local_time_string(char *buf, size_t buflen);
209 static struct tm* localtime_pd (const time_t* clock, struct tm* res);
210 // Fill in buffer with current local time as an ISO-8601 string.
211 // E.g., YYYY-MM-DDThh:mm:ss.mmm+zzzz.
212 // Returns buffer, or NULL if it failed.
213 static char* iso8601_time(char* buffer, size_t buffer_length);
214
215 // Interface for detecting multiprocessor system
216 static inline bool is_MP() {
217 // During bootstrap if _processor_count is not yet initialized
218 // we claim to be MP as that is safest. If any platform has a
219 // stub generator that might be triggered in this phase and for
220 // which being declared MP when in fact not, is a problem - then
221 // the bootstrap routine for the stub generator needs to check
222 // the processor count directly and leave the bootstrap routine
223 // in place until called after initialization has ocurred.
224 return (_processor_count != 1) || AssumeMP;
225 }
226 static julong available_memory();
227 static julong physical_memory();
228 static bool has_allocatable_memory_limit(julong* limit);
229 static bool is_server_class_machine();
230
231 // number of CPUs
232 static int processor_count() {
233 return _processor_count;
234 }
235 static void set_processor_count(int count) { _processor_count = count; }
236
237 // Returns the number of CPUs this process is currently allowed to run on.
238 // Note that on some OSes this can change dynamically.
239 static int active_processor_count();
240
241 // Bind processes to processors.
242 // This is a two step procedure:
243 // first you generate a distribution of processes to processors,
244 // then you bind processes according to that distribution.
245 // Compute a distribution for number of processes to processors.
246 // Stores the processor id's into the distribution array argument.
247 // Returns true if it worked, false if it didn't.
248 static bool distribute_processes(uint length, uint* distribution);
249 // Binds the current process to a processor.
250 // Returns true if it worked, false if it didn't.
251 static bool bind_to_processor(uint processor_id);
252
253 // Give a name to the current thread.
254 static void set_native_thread_name(const char *name);
255
256 // Interface for stack banging (predetect possible stack overflow for
257 // exception processing) There are guard pages, and above that shadow
258 // pages for stack overflow checking.
259 static bool uses_stack_guard_pages();
260 static bool allocate_stack_guard_pages();
261 static void bang_stack_shadow_pages();
262 static bool stack_shadow_pages_available(Thread *thread, methodHandle method);
263
264 // OS interface to Virtual Memory
265
266 // Return the default page size.
267 static int vm_page_size();
268
269 // Returns the page size to use for a region of memory.
270 // region_size / min_pages will always be greater than or equal to the
271 // returned value. The returned value will divide region_size.
272 static size_t page_size_for_region_aligned(size_t region_size, size_t min_pages);
273
274 // Returns the page size to use for a region of memory.
275 // region_size / min_pages will always be greater than or equal to the
276 // returned value. The returned value might not divide region_size.
277 static size_t page_size_for_region_unaligned(size_t region_size, size_t min_pages);
278
279 // Return the largest page size that can be used
280 static size_t max_page_size() {
281 // The _page_sizes array is sorted in descending order.
282 return _page_sizes[0];
283 }
284
285 // Methods for tracing page sizes returned by the above method; enabled by
286 // TracePageSizes. The region_{min,max}_size parameters should be the values
287 // passed to page_size_for_region() and page_size should be the result of that
288 // call. The (optional) base and size parameters should come from the
289 // ReservedSpace base() and size() methods.
290 static void trace_page_sizes(const char* str, const size_t* page_sizes,
291 int count) PRODUCT_RETURN;
292 static void trace_page_sizes(const char* str, const size_t region_min_size,
293 const size_t region_max_size,
294 const size_t page_size,
295 const char* base = NULL,
296 const size_t size = 0) PRODUCT_RETURN;
297
298 static int vm_allocation_granularity();
299 static char* reserve_memory(size_t bytes, char* addr = 0,
300 size_t alignment_hint = 0);
301 static char* reserve_memory(size_t bytes, char* addr,
302 size_t alignment_hint, MEMFLAGS flags);
303 static char* reserve_memory_aligned(size_t size, size_t alignment);
304 static char* attempt_reserve_memory_at(size_t bytes, char* addr);
305 static void split_reserved_memory(char *base, size_t size,
306 size_t split, bool realloc);
307 static bool commit_memory(char* addr, size_t bytes, bool executable);
308 static bool commit_memory(char* addr, size_t size, size_t alignment_hint,
309 bool executable);
310 // Same as commit_memory() that either succeeds or calls
311 // vm_exit_out_of_memory() with the specified mesg.
312 static void commit_memory_or_exit(char* addr, size_t bytes,
313 bool executable, const char* mesg);
314 static void commit_memory_or_exit(char* addr, size_t size,
315 size_t alignment_hint,
316 bool executable, const char* mesg);
317 static bool uncommit_memory(char* addr, size_t bytes);
318 static bool release_memory(char* addr, size_t bytes);
319
320 // Touch memory pages that cover the memory range from start to end (exclusive)
321 // to make the OS back the memory range with actual memory.
322 // Current implementation may not touch the last page if unaligned addresses
323 // are passed.
324 static void pretouch_memory(char* start, char* end);
325
326 enum ProtType { MEM_PROT_NONE, MEM_PROT_READ, MEM_PROT_RW, MEM_PROT_RWX };
327 static bool protect_memory(char* addr, size_t bytes, ProtType prot,
328 bool is_committed = true);
329
330 static bool guard_memory(char* addr, size_t bytes);
331 static bool unguard_memory(char* addr, size_t bytes);
332 static bool create_stack_guard_pages(char* addr, size_t bytes);
333 static bool pd_create_stack_guard_pages(char* addr, size_t bytes);
334 static bool remove_stack_guard_pages(char* addr, size_t bytes);
335
336 static char* map_memory(int fd, const char* file_name, size_t file_offset,
337 char *addr, size_t bytes, bool read_only = false,
338 bool allow_exec = false);
339 static char* remap_memory(int fd, const char* file_name, size_t file_offset,
340 char *addr, size_t bytes, bool read_only,
341 bool allow_exec);
342 static bool unmap_memory(char *addr, size_t bytes);
343 static void free_memory(char *addr, size_t bytes, size_t alignment_hint);
344 static void realign_memory(char *addr, size_t bytes, size_t alignment_hint);
345
346 // NUMA-specific interface
347 static bool numa_has_static_binding();
348 static bool numa_has_group_homing();
349 static void numa_make_local(char *addr, size_t bytes, int lgrp_hint);
350 static void numa_make_global(char *addr, size_t bytes);
351 static size_t numa_get_groups_num();
352 static size_t numa_get_leaf_groups(int *ids, size_t size);
353 static bool numa_topology_changed();
354 static int numa_get_group_id();
355
356 // Page manipulation
357 struct page_info {
358 size_t size;
359 int lgrp_id;
360 };
361 static bool get_page_info(char *start, page_info* info);
362 static char* scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found);
363
364 static char* non_memory_address_word();
365 // reserve, commit and pin the entire memory region
366 static char* reserve_memory_special(size_t size, size_t alignment,
367 char* addr, bool executable);
368 static bool release_memory_special(char* addr, size_t bytes);
369 static void large_page_init();
370 static size_t large_page_size();
371 static bool can_commit_large_page_memory();
372 static bool can_execute_large_page_memory();
373
374 // OS interface to polling page
375 static address get_polling_page() { return _polling_page; }
376 static void set_polling_page(address page) { _polling_page = page; }
377 static bool is_poll_address(address addr) { return addr >= _polling_page && addr < (_polling_page + os::vm_page_size()); }
378 static void make_polling_page_unreadable();
379 static void make_polling_page_readable();
380
381 // Routines used to serialize the thread state without using membars
382 static void serialize_thread_states();
383
384 // Since we write to the serialize page from every thread, we
385 // want stores to be on unique cache lines whenever possible
386 // in order to minimize CPU cross talk. We pre-compute the
387 // amount to shift the thread* to make this offset unique to
388 // each thread.
389 static int get_serialize_page_shift_count() {
390 return SerializePageShiftCount;
391 }
392
393 static void set_serialize_page_mask(uintptr_t mask) {
394 _serialize_page_mask = mask;
395 }
396
397 static unsigned int get_serialize_page_mask() {
398 return _serialize_page_mask;
399 }
400
401 static void set_memory_serialize_page(address page);
402
403 static address get_memory_serialize_page() {
404 return (address)_mem_serialize_page;
405 }
406
407 static inline void write_memory_serialize_page(JavaThread *thread) {
408 uintptr_t page_offset = ((uintptr_t)thread >>
409 get_serialize_page_shift_count()) &
410 get_serialize_page_mask();
411 *(volatile int32_t *)((uintptr_t)_mem_serialize_page+page_offset) = 1;
412 }
413
414 static bool is_memory_serialize_page(JavaThread *thread, address addr) {
415 if (UseMembar) return false;
416 // Previously this function calculated the exact address of this
417 // thread's serialize page, and checked if the faulting address
418 // was equal. However, some platforms mask off faulting addresses
419 // to the page size, so now we just check that the address is
420 // within the page. This makes the thread argument unnecessary,
421 // but we retain the NULL check to preserve existing behavior.
422 if (thread == NULL) return false;
423 address page = (address) _mem_serialize_page;
424 return addr >= page && addr < (page + os::vm_page_size());
425 }
426
427 static void block_on_serialize_page_trap();
428
429 // threads
430
431 enum ThreadType {
432 vm_thread,
433 cgc_thread, // Concurrent GC thread
434 pgc_thread, // Parallel GC thread
435 java_thread,
436 compiler_thread,
437 watcher_thread,
438 os_thread
439 };
440
441 static bool create_thread(Thread* thread,
442 ThreadType thr_type,
443 size_t stack_size = 0);
444 static bool create_main_thread(JavaThread* thread);
445 static bool create_attached_thread(JavaThread* thread);
446 static void pd_start_thread(Thread* thread);
447 static void start_thread(Thread* thread);
448
449 static void initialize_thread(Thread* thr);
450 static void free_thread(OSThread* osthread);
451
452 // thread id on Linux/64bit is 64bit, on Windows and Solaris, it's 32bit
453 static intx current_thread_id();
454 static int current_process_id();
455 static int sleep(Thread* thread, jlong ms, bool interruptable);
456 // Short standalone OS sleep suitable for slow path spin loop.
457 // Ignores Thread.interrupt() (so keep it short).
458 // ms = 0, will sleep for the least amount of time allowed by the OS.
459 static void naked_short_sleep(jlong ms);
460 static void infinite_sleep(); // never returns, use with CAUTION
461 static void naked_yield () ;
462 static OSReturn set_priority(Thread* thread, ThreadPriority priority);
463 static OSReturn get_priority(const Thread* const thread, ThreadPriority& priority);
464
465 static void interrupt(Thread* thread);
466 static bool is_interrupted(Thread* thread, bool clear_interrupted);
467
468 static int pd_self_suspend_thread(Thread* thread);
469
470 static ExtendedPC fetch_frame_from_context(void* ucVoid, intptr_t** sp, intptr_t** fp);
471 static frame fetch_frame_from_context(void* ucVoid);
472
473 static ExtendedPC get_thread_pc(Thread *thread);
474 static void breakpoint();
475
476 static address current_stack_pointer();
477 static address current_stack_base();
478 static size_t current_stack_size();
479
480 static void verify_stack_alignment() PRODUCT_RETURN;
481
482 static int message_box(const char* title, const char* message);
483 static char* do_you_want_to_debug(const char* message);
484
485 // run cmd in a separate process and return its exit code; or -1 on failures
486 static int fork_and_exec(char *cmd);
487
488 // Call ::exit() on all platforms but Windows
489 static void exit(int num);
490
491 // Terminate the VM, but don't exit the process
492 static void shutdown();
493
494 // Terminate with an error. Default is to generate a core file on platforms
495 // that support such things. This calls shutdown() and then aborts.
496 static void abort(bool dump_core = true, void *siginfo = NULL, void *context = NULL);
497
498 // Die immediately, no exit hook, no abort hook, no cleanup.
499 static void die();
500
501 // File i/o operations
502 static const int default_file_open_flags();
503 static int open(const char *path, int oflag, int mode);
504 static FILE* open(int fd, const char* mode);
505 static int close(int fd);
506 static jlong lseek(int fd, jlong offset, int whence);
507 static char* native_path(char *path);
508 static int ftruncate(int fd, jlong length);
509 static int fsync(int fd);
510 static int available(int fd, jlong *bytes);
511
512 //File i/o operations
513
514 static size_t read(int fd, void *buf, unsigned int nBytes);
515 static size_t read_at(int fd, void *buf, unsigned int nBytes, jlong offset);
516 static size_t restartable_read(int fd, void *buf, unsigned int nBytes);
517 static size_t write(int fd, const void *buf, unsigned int nBytes);
518
519 // Reading directories.
520 static DIR* opendir(const char* dirname);
521 static int readdir_buf_size(const char *path);
522 static struct dirent* readdir(DIR* dirp, dirent* dbuf);
523 static int closedir(DIR* dirp);
524
525 // Dynamic library extension
526 static const char* dll_file_extension();
527
528 static const char* get_temp_directory();
529 static const char* get_current_directory(char *buf, size_t buflen);
530
531 // Builds a platform-specific full library path given a ld path and lib name
532 // Returns true if buffer contains full path to existing file, false otherwise
533 static bool dll_build_name(char* buffer, size_t size,
534 const char* pathname, const char* fname);
535
536 // Symbol lookup, find nearest function name; basically it implements
537 // dladdr() for all platforms. Name of the nearest function is copied
538 // to buf. Distance from its base address is optionally returned as offset.
539 // If function name is not found, buf[0] is set to '\0' and offset is
540 // set to -1 (if offset is non-NULL).
541 static bool dll_address_to_function_name(address addr, char* buf,
542 int buflen, int* offset);
543
544 // Locate DLL/DSO. On success, full path of the library is copied to
545 // buf, and offset is optionally set to be the distance between addr
546 // and the library's base address. On failure, buf[0] is set to '\0'
547 // and offset is set to -1 (if offset is non-NULL).
548 static bool dll_address_to_library_name(address addr, char* buf,
549 int buflen, int* offset);
550
551 // Find out whether the pc is in the static code for jvm.dll/libjvm.so.
552 static bool address_is_in_vm(address addr);
553
554 // Loads .dll/.so and
555 // in case of error it checks if .dll/.so was built for the
556 // same architecture as HotSpot is running on
557 static void* dll_load(const char *name, char *ebuf, int ebuflen);
558
559 // lookup symbol in a shared library
560 static void* dll_lookup(void* handle, const char* name);
561
562 // Unload library
563 static void dll_unload(void *lib);
564
565 // Callback for loaded module information
566 // Input parameters:
567 // char* module_file_name,
568 // address module_base_addr,
569 // address module_top_addr,
570 // void* param
571 typedef int (*LoadedModulesCallbackFunc)(const char *, address, address, void *);
572
573 static int get_loaded_modules_info(LoadedModulesCallbackFunc callback, void *param);
574
575 // Return the handle of this process
576 static void* get_default_process_handle();
577
578 // Check for static linked agent library
579 static bool find_builtin_agent(AgentLibrary *agent_lib, const char *syms[],
580 size_t syms_len);
581
582 // Find agent entry point
583 static void *find_agent_function(AgentLibrary *agent_lib, bool check_lib,
584 const char *syms[], size_t syms_len);
585
586 // Print out system information; they are called by fatal error handler.
587 // Output format may be different on different platforms.
588 static void print_os_info(outputStream* st);
589 static void print_os_info_brief(outputStream* st);
590 static void print_cpu_info(outputStream* st);
591 static void pd_print_cpu_info(outputStream* st);
592 static void print_memory_info(outputStream* st);
593 static void print_dll_info(outputStream* st);
594 static void print_environment_variables(outputStream* st, const char** env_list, char* buffer, int len);
595 static void print_context(outputStream* st, void* context);
596 static void print_register_info(outputStream* st, void* context);
597 static void print_siginfo(outputStream* st, void* siginfo);
598 static void print_signal_handlers(outputStream* st, char* buf, size_t buflen);
599 static void print_date_and_time(outputStream* st);
600
601 static void print_location(outputStream* st, intptr_t x, bool verbose = false);
602 static size_t lasterror(char *buf, size_t len);
603 static int get_last_error();
604
605 // Determines whether the calling process is being debugged by a user-mode debugger.
606 static bool is_debugger_attached();
607
608 // wait for a key press if PauseAtExit is set
609 static void wait_for_keypress_at_exit(void);
610
611 // The following two functions are used by fatal error handler to trace
612 // native (C) frames. They are not part of frame.hpp/frame.cpp because
613 // frame.hpp/cpp assume thread is JavaThread, and also because different
614 // OS/compiler may have different convention or provide different API to
615 // walk C frames.
616 //
617 // We don't attempt to become a debugger, so we only follow frames if that
618 // does not require a lookup in the unwind table, which is part of the binary
619 // file but may be unsafe to read after a fatal error. So on x86, we can
620 // only walk stack if %ebp is used as frame pointer; on ia64, it's not
621 // possible to walk C stack without having the unwind table.
622 static bool is_first_C_frame(frame *fr);
623 static frame get_sender_for_C_frame(frame *fr);
624
625 // return current frame. pc() and sp() are set to NULL on failure.
626 static frame current_frame();
627
628 static void print_hex_dump(outputStream* st, address start, address end, int unitsize);
629
630 // returns a string to describe the exception/signal;
631 // returns NULL if exception_code is not an OS exception/signal.
632 static const char* exception_name(int exception_code, char* buf, size_t buflen);
633
634 // Returns native Java library, loads if necessary
635 static void* native_java_library();
636
637 // Fills in path to jvm.dll/libjvm.so (used by the Disassembler)
638 static void jvm_path(char *buf, jint buflen);
639
640 // Returns true if we are running in a headless jre.
641 static bool is_headless_jre();
642
643 // JNI names
644 static void print_jni_name_prefix_on(outputStream* st, int args_size);
645 static void print_jni_name_suffix_on(outputStream* st, int args_size);
646
647 // Init os specific system properties values
648 static void init_system_properties_values();
649
650 // IO operations, non-JVM_ version.
651 static int stat(const char* path, struct stat* sbuf);
652 static bool dir_is_empty(const char* path);
653
654 // IO operations on binary files
655 static int create_binary_file(const char* path, bool rewrite_existing);
656 static jlong current_file_offset(int fd);
657 static jlong seek_to_file_offset(int fd, jlong offset);
658
659 // Thread Local Storage
660 static int allocate_thread_local_storage();
661 static void thread_local_storage_at_put(int index, void* value);
662 static void* thread_local_storage_at(int index);
663 static void free_thread_local_storage(int index);
664
665 // Retrieve native stack frames.
666 // Parameter:
667 // stack: an array to storage stack pointers.
668 // frames: size of above array.
669 // toSkip: number of stack frames to skip at the beginning.
670 // Return: number of stack frames captured.
671 static int get_native_stack(address* stack, int size, int toSkip = 0);
672
673 // General allocation (must be MT-safe)
674 static void* malloc (size_t size, MEMFLAGS flags, const NativeCallStack& stack);
675 static void* malloc (size_t size, MEMFLAGS flags);
676 static void* realloc (void *memblock, size_t size, MEMFLAGS flag, const NativeCallStack& stack);
677 static void* realloc (void *memblock, size_t size, MEMFLAGS flag);
678
679 static void free (void *memblock);
680 static bool check_heap(bool force = false); // verify C heap integrity
681 static char* strdup(const char *, MEMFLAGS flags = mtInternal); // Like strdup
682 // Like strdup, but exit VM when strdup() returns NULL
683 static char* strdup_check_oom(const char*, MEMFLAGS flags = mtInternal);
684
685 #ifndef PRODUCT
686 static julong num_mallocs; // # of calls to malloc/realloc
687 static julong alloc_bytes; // # of bytes allocated
688 static julong num_frees; // # of calls to free
689 static julong free_bytes; // # of bytes freed
690 #endif
691
692 // SocketInterface (ex HPI SocketInterface )
693 static int socket(int domain, int type, int protocol);
694 static int socket_close(int fd);
695 static int recv(int fd, char* buf, size_t nBytes, uint flags);
696 static int send(int fd, char* buf, size_t nBytes, uint flags);
697 static int raw_send(int fd, char* buf, size_t nBytes, uint flags);
698 static int connect(int fd, struct sockaddr* him, socklen_t len);
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_dump_limit(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 // Amount beyond the callee frame size that we bang the stack.
762 static int extra_bang_size_in_bytes();
763
764 // Extensions
765 #include "runtime/os_ext.hpp"
766
767 public:
768 class CrashProtectionCallback : public StackObj {
769 public:
770 virtual void call() = 0;
771 };
772
773 // Platform dependent stuff
774 #ifdef TARGET_OS_FAMILY_linux
775 # include "os_linux.hpp"
776 # include "os_posix.hpp"
777 #endif
778 #ifdef TARGET_OS_FAMILY_solaris
779 # include "os_solaris.hpp"
780 # include "os_posix.hpp"
781 #endif
782 #ifdef TARGET_OS_FAMILY_windows
783 # include "os_windows.hpp"
784 #endif
785 #ifdef TARGET_OS_FAMILY_aix
786 # include "os_aix.hpp"
787 # include "os_posix.hpp"
788 #endif
789 #ifdef TARGET_OS_FAMILY_bsd
790 # include "os_posix.hpp"
791 # include "os_bsd.hpp"
792 #endif
793 #ifdef TARGET_OS_ARCH_linux_x86
794 # include "os_linux_x86.hpp"
795 #endif
796 #ifdef TARGET_OS_ARCH_linux_sparc
797 # include "os_linux_sparc.hpp"
798 #endif
799 #ifdef TARGET_OS_ARCH_linux_zero
800 # include "os_linux_zero.hpp"
801 #endif
802 #ifdef TARGET_OS_ARCH_solaris_x86
803 # include "os_solaris_x86.hpp"
804 #endif
805 #ifdef TARGET_OS_ARCH_solaris_sparc
806 # include "os_solaris_sparc.hpp"
807 #endif
808 #ifdef TARGET_OS_ARCH_windows_x86
809 # include "os_windows_x86.hpp"
810 #endif
811 #ifdef TARGET_OS_ARCH_linux_arm
812 # include "os_linux_arm.hpp"
813 #endif
814 #ifdef TARGET_OS_ARCH_linux_ppc
815 # include "os_linux_ppc.hpp"
816 #endif
817 #ifdef TARGET_OS_ARCH_aix_ppc
818 # include "os_aix_ppc.hpp"
819 #endif
820 #ifdef TARGET_OS_ARCH_linux_aarch64
821 # include "os_linux_aarch64.hpp"
822 #endif
823 #ifdef TARGET_OS_ARCH_bsd_x86
824 # include "os_bsd_x86.hpp"
825 #endif
826 #ifdef TARGET_OS_ARCH_bsd_zero
827 # include "os_bsd_zero.hpp"
828 #endif
829
830 #ifndef OS_NATIVE_THREAD_CREATION_FAILED_MSG
831 #define OS_NATIVE_THREAD_CREATION_FAILED_MSG "unable to create native thread: possibly out of memory or process/resource limits reached"
832 #endif
833
834 public:
835 #ifndef PLATFORM_PRINT_NATIVE_STACK
836 // No platform-specific code for printing the native stack.
837 static bool platform_print_native_stack(outputStream* st, void* context,
838 char *buf, int buf_size) {
839 return false;
840 }
841 #endif
842
843 // debugging support (mostly used by debug.cpp but also fatal error handler)
844 static bool find(address pc, outputStream* st = tty); // OS specific function to make sense out of an address
845
846 static bool dont_yield(); // when true, JVM_Yield() is nop
847 static void print_statistics();
848
849 // Thread priority helpers (implemented in OS-specific part)
850 static OSReturn set_native_priority(Thread* thread, int native_prio);
851 static OSReturn get_native_priority(const Thread* const thread, int* priority_ptr);
852 static int java_to_os_priority[CriticalPriority + 1];
853 // Hint to the underlying OS that a task switch would not be good.
854 // Void return because it's a hint and can fail.
855 static void hint_no_preempt();
856 static const char* native_thread_creation_failed_msg() {
857 return OS_NATIVE_THREAD_CREATION_FAILED_MSG;
858 }
859
860 // Used at creation if requested by the diagnostic flag PauseAtStartup.
861 // Causes the VM to wait until an external stimulus has been applied
862 // (for Unix, that stimulus is a signal, for Windows, an external
863 // ResumeThread call)
864 static void pause();
865
866 // Builds a platform dependent Agent_OnLoad_<libname> function name
867 // which is used to find statically linked in agents.
868 static char* build_agent_function_name(const char *sym, const char *cname,
869 bool is_absolute_path);
870
871 class SuspendedThreadTaskContext {
872 public:
873 SuspendedThreadTaskContext(Thread* thread, void *ucontext) : _thread(thread), _ucontext(ucontext) {}
874 Thread* thread() const { return _thread; }
875 void* ucontext() const { return _ucontext; }
876 private:
877 Thread* _thread;
878 void* _ucontext;
879 };
880
881 class SuspendedThreadTask {
882 public:
883 SuspendedThreadTask(Thread* thread) : _thread(thread), _done(false) {}
884 virtual ~SuspendedThreadTask() {}
885 void run();
886 bool is_done() { return _done; }
887 virtual void do_task(const SuspendedThreadTaskContext& context) = 0;
888 protected:
889 private:
890 void internal_do_task();
891 Thread* _thread;
892 bool _done;
893 };
894
895 #ifndef TARGET_OS_FAMILY_windows
896 // Suspend/resume support
897 // Protocol:
898 //
899 // a thread starts in SR_RUNNING
900 //
901 // SR_RUNNING can go to
902 // * SR_SUSPEND_REQUEST when the WatcherThread wants to suspend it
903 // SR_SUSPEND_REQUEST can go to
904 // * SR_RUNNING if WatcherThread decides it waited for SR_SUSPENDED too long (timeout)
905 // * SR_SUSPENDED if the stopped thread receives the signal and switches state
906 // SR_SUSPENDED can go to
907 // * SR_WAKEUP_REQUEST when the WatcherThread has done the work and wants to resume
908 // SR_WAKEUP_REQUEST can go to
909 // * SR_RUNNING when the stopped thread receives the signal
910 // * SR_WAKEUP_REQUEST on timeout (resend the signal and try again)
911 class SuspendResume {
912 public:
913 enum State {
914 SR_RUNNING,
915 SR_SUSPEND_REQUEST,
916 SR_SUSPENDED,
917 SR_WAKEUP_REQUEST
918 };
919
920 private:
921 volatile State _state;
922
923 private:
924 /* try to switch state from state "from" to state "to"
925 * returns the state set after the method is complete
926 */
927 State switch_state(State from, State to);
928
929 public:
930 SuspendResume() : _state(SR_RUNNING) { }
931
932 State state() const { return _state; }
933
934 State request_suspend() {
935 return switch_state(SR_RUNNING, SR_SUSPEND_REQUEST);
936 }
937
938 State cancel_suspend() {
939 return switch_state(SR_SUSPEND_REQUEST, SR_RUNNING);
940 }
941
942 State suspended() {
943 return switch_state(SR_SUSPEND_REQUEST, SR_SUSPENDED);
944 }
945
946 State request_wakeup() {
947 return switch_state(SR_SUSPENDED, SR_WAKEUP_REQUEST);
948 }
949
950 State running() {
951 return switch_state(SR_WAKEUP_REQUEST, SR_RUNNING);
952 }
953
954 bool is_running() const {
955 return _state == SR_RUNNING;
956 }
957
958 bool is_suspend_request() const {
959 return _state == SR_SUSPEND_REQUEST;
960 }
961
962 bool is_suspended() const {
963 return _state == SR_SUSPENDED;
964 }
965 };
966 #endif
967
968
969 protected:
970 static long _rand_seed; // seed for random number generator
971 static int _processor_count; // number of processors
972
973 static char* format_boot_path(const char* format_string,
974 const char* home,
975 int home_len,
976 char fileSep,
977 char pathSep);
978 static bool set_boot_path(char fileSep, char pathSep);
979 static char** split_path(const char* path, int* n);
980
981 };
982
983 // Note that "PAUSE" is almost always used with synchronization
984 // so arguably we should provide Atomic::SpinPause() instead
985 // of the global SpinPause() with C linkage.
986 // It'd also be eligible for inlining on many platforms.
987
988 extern "C" int SpinPause();
989
990 #endif // SHARE_VM_RUNTIME_OS_HPP