1 /*
2 * Copyright (c) 1997, 2016, 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, const methodHandle& method, JavaCallArguments* args, Thread* thread);
100
101 class MallocTracker;
102
103 class os: AllStatic {
104 friend class VMStructs;
105 friend class JVMCIVMStructs;
106 friend class MallocTracker;
107 public:
108 enum { page_sizes_max = 9 }; // Size of _page_sizes array (8 plus a sentinel)
109
110 private:
111 static OSThread* _starting_thread;
112 static address _polling_page;
113 static volatile int32_t * _mem_serialize_page;
114 static uintptr_t _serialize_page_mask;
115 public:
116 static size_t _page_sizes[page_sizes_max];
117
118 private:
119 static void init_page_sizes(size_t default_page_size) {
120 _page_sizes[0] = default_page_size;
121 _page_sizes[1] = 0; // sentinel
122 }
123
124 static char* pd_reserve_memory(size_t bytes, char* addr = 0,
125 size_t alignment_hint = 0);
126 static char* pd_attempt_reserve_memory_at(size_t bytes, char* addr);
127 static void pd_split_reserved_memory(char *base, size_t size,
128 size_t split, bool realloc);
129 static bool pd_commit_memory(char* addr, size_t bytes, bool executable);
130 static bool pd_commit_memory(char* addr, size_t size, size_t alignment_hint,
131 bool executable);
132 // Same as pd_commit_memory() that either succeeds or calls
133 // vm_exit_out_of_memory() with the specified mesg.
134 static void pd_commit_memory_or_exit(char* addr, size_t bytes,
135 bool executable, const char* mesg);
136 static void pd_commit_memory_or_exit(char* addr, size_t size,
137 size_t alignment_hint,
138 bool executable, const char* mesg);
139 static bool pd_uncommit_memory(char* addr, size_t bytes);
140 static bool pd_release_memory(char* addr, size_t bytes);
141
142 static char* pd_map_memory(int fd, const char* file_name, size_t file_offset,
143 char *addr, size_t bytes, bool read_only = false,
144 bool allow_exec = false);
145 static char* pd_remap_memory(int fd, const char* file_name, size_t file_offset,
146 char *addr, size_t bytes, bool read_only,
147 bool allow_exec);
148 static bool pd_unmap_memory(char *addr, size_t bytes);
149 static void pd_free_memory(char *addr, size_t bytes, size_t alignment_hint);
150 static void pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint);
151
152 static size_t page_size_for_region(size_t region_size, size_t min_pages, bool must_be_aligned);
153
154 // Get summary strings for system information in buffer provided
155 static bool get_host_name(char* buf, size_t buflen) PRODUCT_RETURN_(return false;); // true if available
156 static void get_summary_cpu_info(char* buf, size_t buflen);
157 static void get_summary_os_info(char* buf, size_t buflen);
158
159 public:
160 static void init(void); // Called before command line parsing
161 static void init_before_ergo(void); // Called after command line parsing
162 // before VM ergonomics processing.
163 static jint init_2(void); // Called after command line parsing
164 // and VM ergonomics processing
165 static void init_globals(void) { // Called from init_globals() in init.cpp
166 init_globals_ext();
167 }
168
169 // File names are case-insensitive on windows only
170 // Override me as needed
171 static int file_name_strcmp(const char* s1, const char* s2);
172
173 // unset environment variable
174 static bool unsetenv(const char* name);
175
176 static bool have_special_privileges();
177
178 static jlong javaTimeMillis();
179 static jlong javaTimeNanos();
180 static void javaTimeNanos_info(jvmtiTimerInfo *info_ptr);
181 static void javaTimeSystemUTC(jlong &seconds, jlong &nanos);
182 static void run_periodic_checks();
183 static bool supports_monotonic_clock();
184
185 // Returns the elapsed time in seconds since the vm started.
186 static double elapsedTime();
187
188 // Returns real time in seconds since an arbitrary point
189 // in the past.
190 static bool getTimesSecs(double* process_real_time,
191 double* process_user_time,
192 double* process_system_time);
193
194 // Interface to the performance counter
195 static jlong elapsed_counter();
196 static jlong elapsed_frequency();
197
198 // The "virtual time" of a thread is the amount of time a thread has
199 // actually run. The first function indicates whether the OS supports
200 // this functionality for the current thread, and if so:
201 // * the second enables vtime tracking (if that is required).
202 // * the third tells whether vtime is enabled.
203 // * the fourth returns the elapsed virtual time for the current
204 // thread.
205 static bool supports_vtime();
206 static bool enable_vtime();
207 static bool vtime_enabled();
208 static double elapsedVTime();
209
210 // Return current local time in a string (YYYY-MM-DD HH:MM:SS).
211 // It is MT safe, but not async-safe, as reading time zone
212 // information may require a lock on some platforms.
213 static char* local_time_string(char *buf, size_t buflen);
214 static struct tm* localtime_pd (const time_t* clock, struct tm* res);
215 // Fill in buffer with current local time as an ISO-8601 string.
216 // E.g., YYYY-MM-DDThh:mm:ss.mmm+zzzz.
217 // Returns buffer, or NULL if it failed.
218 static char* iso8601_time(char* buffer, size_t buffer_length);
219
220 // Interface for detecting multiprocessor system
221 static inline bool is_MP() {
222 // During bootstrap if _processor_count is not yet initialized
223 // we claim to be MP as that is safest. If any platform has a
224 // stub generator that might be triggered in this phase and for
225 // which being declared MP when in fact not, is a problem - then
226 // the bootstrap routine for the stub generator needs to check
227 // the processor count directly and leave the bootstrap routine
228 // in place until called after initialization has ocurred.
229 return (_processor_count != 1) || AssumeMP;
230 }
231 static julong available_memory();
232 static julong physical_memory();
233 static bool has_allocatable_memory_limit(julong* limit);
234 static bool is_server_class_machine();
235
236 // number of CPUs
237 static int processor_count() {
238 return _processor_count;
239 }
240 static void set_processor_count(int count) { _processor_count = count; }
241
242 // Returns the number of CPUs this process is currently allowed to run on.
243 // Note that on some OSes this can change dynamically.
244 static int active_processor_count();
245
246 // Bind processes to processors.
247 // This is a two step procedure:
248 // first you generate a distribution of processes to processors,
249 // then you bind processes according to that distribution.
250 // Compute a distribution for number of processes to processors.
251 // Stores the processor id's into the distribution array argument.
252 // Returns true if it worked, false if it didn't.
253 static bool distribute_processes(uint length, uint* distribution);
254 // Binds the current process to a processor.
255 // Returns true if it worked, false if it didn't.
256 static bool bind_to_processor(uint processor_id);
257
258 // Give a name to the current thread.
259 static void set_native_thread_name(const char *name);
260
261 // Interface for stack banging (predetect possible stack overflow for
262 // exception processing) There are guard pages, and above that shadow
263 // pages for stack overflow checking.
264 static bool uses_stack_guard_pages();
265 static bool allocate_stack_guard_pages();
266 static void map_stack_shadow_pages();
267 static bool stack_shadow_pages_available(Thread *thread, const methodHandle& method);
268
269 // OS interface to Virtual Memory
270
271 // Return the default page size.
272 static int vm_page_size();
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 will divide region_size.
277 static size_t page_size_for_region_aligned(size_t region_size, size_t min_pages);
278
279 // Returns the page size to use for a region of memory.
280 // region_size / min_pages will always be greater than or equal to the
281 // returned value. The returned value might not divide region_size.
282 static size_t page_size_for_region_unaligned(size_t region_size, size_t min_pages);
283
284 // Return the largest page size that can be used
285 static size_t max_page_size() {
286 // The _page_sizes array is sorted in descending order.
287 return _page_sizes[0];
288 }
289
290 // Methods for tracing page sizes returned by the above method; enabled by
291 // TracePageSizes. The region_{min,max}_size parameters should be the values
292 // passed to page_size_for_region() and page_size should be the result of that
293 // call. The (optional) base and size parameters should come from the
294 // ReservedSpace base() and size() methods.
295 static void trace_page_sizes(const char* str, const size_t* page_sizes,
296 int count) PRODUCT_RETURN;
297 static void trace_page_sizes(const char* str, const size_t region_min_size,
298 const size_t region_max_size,
299 const size_t page_size,
300 const char* base = NULL,
301 const size_t size = 0) PRODUCT_RETURN;
302
303 static int vm_allocation_granularity();
304 static char* reserve_memory(size_t bytes, char* addr = 0,
305 size_t alignment_hint = 0);
306 static char* reserve_memory(size_t bytes, char* addr,
307 size_t alignment_hint, MEMFLAGS flags);
308 static char* reserve_memory_aligned(size_t size, size_t alignment);
309 static char* attempt_reserve_memory_at(size_t bytes, char* addr);
310 static void split_reserved_memory(char *base, size_t size,
311 size_t split, bool realloc);
312 static bool commit_memory(char* addr, size_t bytes, bool executable);
313 static bool commit_memory(char* addr, size_t size, size_t alignment_hint,
314 bool executable);
315 // Same as commit_memory() that either succeeds or calls
316 // vm_exit_out_of_memory() with the specified mesg.
317 static void commit_memory_or_exit(char* addr, size_t bytes,
318 bool executable, const char* mesg);
319 static void commit_memory_or_exit(char* addr, size_t size,
320 size_t alignment_hint,
321 bool executable, const char* mesg);
322 static bool uncommit_memory(char* addr, size_t bytes);
323 static bool release_memory(char* addr, size_t bytes);
324
325 // Touch memory pages that cover the memory range from start to end (exclusive)
326 // to make the OS back the memory range with actual memory.
327 // Current implementation may not touch the last page if unaligned addresses
328 // are passed.
329 static void pretouch_memory(char* start, char* end);
330
331 enum ProtType { MEM_PROT_NONE, MEM_PROT_READ, MEM_PROT_RW, MEM_PROT_RWX };
332 static bool protect_memory(char* addr, size_t bytes, ProtType prot,
333 bool is_committed = true);
334
335 static bool guard_memory(char* addr, size_t bytes);
336 static bool unguard_memory(char* addr, size_t bytes);
337 static bool create_stack_guard_pages(char* addr, size_t bytes);
338 static bool pd_create_stack_guard_pages(char* addr, size_t bytes);
339 static bool remove_stack_guard_pages(char* addr, size_t bytes);
340
341 static char* map_memory(int fd, const char* file_name, size_t file_offset,
342 char *addr, size_t bytes, bool read_only = false,
343 bool allow_exec = false);
344 static char* remap_memory(int fd, const char* file_name, size_t file_offset,
345 char *addr, size_t bytes, bool read_only,
346 bool allow_exec);
347 static bool unmap_memory(char *addr, size_t bytes);
348 static void free_memory(char *addr, size_t bytes, size_t alignment_hint);
349 static void realign_memory(char *addr, size_t bytes, size_t alignment_hint);
350
351 // NUMA-specific interface
352 static bool numa_has_static_binding();
353 static bool numa_has_group_homing();
354 static void numa_make_local(char *addr, size_t bytes, int lgrp_hint);
355 static void numa_make_global(char *addr, size_t bytes);
356 static size_t numa_get_groups_num();
357 static size_t numa_get_leaf_groups(int *ids, size_t size);
358 static bool numa_topology_changed();
359 static int numa_get_group_id();
360
361 // Page manipulation
362 struct page_info {
363 size_t size;
364 int lgrp_id;
365 };
366 static bool get_page_info(char *start, page_info* info);
367 static char* scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found);
368
369 static char* non_memory_address_word();
370 // reserve, commit and pin the entire memory region
371 static char* reserve_memory_special(size_t size, size_t alignment,
372 char* addr, bool executable);
373 static bool release_memory_special(char* addr, size_t bytes);
374 static void large_page_init();
375 static size_t large_page_size();
376 static bool can_commit_large_page_memory();
377 static bool can_execute_large_page_memory();
378
379 // OS interface to polling page
380 static address get_polling_page() { return _polling_page; }
381 static void set_polling_page(address page) { _polling_page = page; }
382 static bool is_poll_address(address addr) { return addr >= _polling_page && addr < (_polling_page + os::vm_page_size()); }
383 static void make_polling_page_unreadable();
384 static void make_polling_page_readable();
385
386 // Routines used to serialize the thread state without using membars
387 static void serialize_thread_states();
388
389 // Since we write to the serialize page from every thread, we
390 // want stores to be on unique cache lines whenever possible
391 // in order to minimize CPU cross talk. We pre-compute the
392 // amount to shift the thread* to make this offset unique to
393 // each thread.
394 static int get_serialize_page_shift_count() {
395 return SerializePageShiftCount;
396 }
397
398 static void set_serialize_page_mask(uintptr_t mask) {
399 _serialize_page_mask = mask;
400 }
401
402 static unsigned int get_serialize_page_mask() {
403 return _serialize_page_mask;
404 }
405
406 static void set_memory_serialize_page(address page);
407
408 static address get_memory_serialize_page() {
409 return (address)_mem_serialize_page;
410 }
411
412 static inline void write_memory_serialize_page(JavaThread *thread) {
413 uintptr_t page_offset = ((uintptr_t)thread >>
414 get_serialize_page_shift_count()) &
415 get_serialize_page_mask();
416 *(volatile int32_t *)((uintptr_t)_mem_serialize_page+page_offset) = 1;
417 }
418
419 static bool is_memory_serialize_page(JavaThread *thread, address addr) {
420 if (UseMembar) return false;
421 // Previously this function calculated the exact address of this
422 // thread's serialize page, and checked if the faulting address
423 // was equal. However, some platforms mask off faulting addresses
424 // to the page size, so now we just check that the address is
425 // within the page. This makes the thread argument unnecessary,
426 // but we retain the NULL check to preserve existing behavior.
427 if (thread == NULL) return false;
428 address page = (address) _mem_serialize_page;
429 return addr >= page && addr < (page + os::vm_page_size());
430 }
431
432 static void block_on_serialize_page_trap();
433
434 // threads
435
436 enum ThreadType {
437 vm_thread,
438 cgc_thread, // Concurrent GC thread
439 pgc_thread, // Parallel GC thread
440 java_thread,
441 compiler_thread,
442 watcher_thread,
443 os_thread
444 };
445
446 static bool create_thread(Thread* thread,
447 ThreadType thr_type,
448 size_t stack_size = 0);
449 static bool create_main_thread(JavaThread* thread);
450 static bool create_attached_thread(JavaThread* thread);
451 static void pd_start_thread(Thread* thread);
452 static void start_thread(Thread* thread);
453
454 static void initialize_thread(Thread* thr);
455 static void free_thread(OSThread* osthread);
456
457 // thread id on Linux/64bit is 64bit, on Windows and Solaris, it's 32bit
458 static intx current_thread_id();
459 static int current_process_id();
460 static int sleep(Thread* thread, jlong ms, bool interruptable);
461 // Short standalone OS sleep suitable for slow path spin loop.
462 // Ignores Thread.interrupt() (so keep it short).
463 // ms = 0, will sleep for the least amount of time allowed by the OS.
464 static void naked_short_sleep(jlong ms);
465 static void infinite_sleep(); // never returns, use with CAUTION
466 static void naked_yield () ;
467 static OSReturn set_priority(Thread* thread, ThreadPriority priority);
468 static OSReturn get_priority(const Thread* const thread, ThreadPriority& priority);
469
470 static void interrupt(Thread* thread);
471 static bool is_interrupted(Thread* thread, bool clear_interrupted);
472
473 static int pd_self_suspend_thread(Thread* thread);
474
475 static ExtendedPC fetch_frame_from_context(const void* ucVoid, intptr_t** sp, intptr_t** fp);
476 static frame fetch_frame_from_context(const void* ucVoid);
477 static frame fetch_frame_from_ucontext(Thread* thread, void* ucVoid);
478
479 static ExtendedPC get_thread_pc(Thread *thread);
480 static void breakpoint();
481 static bool start_debugging(char *buf, int buflen);
482
483 static address current_stack_pointer();
484 static address current_stack_base();
485 static size_t current_stack_size();
486
487 static void verify_stack_alignment() PRODUCT_RETURN;
488
489 static bool message_box(const char* title, const char* message);
490 static char* do_you_want_to_debug(const char* message);
491
492 // run cmd in a separate process and return its exit code; or -1 on failures
493 static int fork_and_exec(char *cmd);
494
495 // Call ::exit() on all platforms but Windows
496 static void exit(int num);
497
498 // Terminate the VM, but don't exit the process
499 static void shutdown();
500
501 // Terminate with an error. Default is to generate a core file on platforms
502 // that support such things. This calls shutdown() and then aborts.
503 static void abort(bool dump_core, void *siginfo, const void *context);
504 static void abort(bool dump_core = true);
505
506 // Die immediately, no exit hook, no abort hook, no cleanup.
507 static void die();
508
509 // File i/o operations
510 static const int default_file_open_flags();
511 static int open(const char *path, int oflag, int mode);
512 static FILE* open(int fd, const char* mode);
513 static int close(int fd);
514 static jlong lseek(int fd, jlong offset, int whence);
515 static char* native_path(char *path);
516 static int ftruncate(int fd, jlong length);
517 static int fsync(int fd);
518 static int available(int fd, jlong *bytes);
519 static void flockfile(FILE* fp);
520 static void funlockfile(FILE* fp);
521
522 //File i/o operations
523
524 static size_t read(int fd, void *buf, unsigned int nBytes);
525 static size_t read_at(int fd, void *buf, unsigned int nBytes, jlong offset);
526 static size_t restartable_read(int fd, void *buf, unsigned int nBytes);
527 static size_t write(int fd, const void *buf, unsigned int nBytes);
528
529 // Reading directories.
530 static DIR* opendir(const char* dirname);
531 static int readdir_buf_size(const char *path);
532 static struct dirent* readdir(DIR* dirp, dirent* dbuf);
533 static int closedir(DIR* dirp);
534
535 // Dynamic library extension
536 static const char* dll_file_extension();
537
538 static const char* get_temp_directory();
539 static const char* get_current_directory(char *buf, size_t buflen);
540
541 // Builds a platform-specific full library path given a ld path and lib name
542 // Returns true if buffer contains full path to existing file, false otherwise
543 static bool dll_build_name(char* buffer, size_t size,
544 const char* pathname, const char* fname);
545
546 // Symbol lookup, find nearest function name; basically it implements
547 // dladdr() for all platforms. Name of the nearest function is copied
548 // to buf. Distance from its base address is optionally returned as offset.
549 // If function name is not found, buf[0] is set to '\0' and offset is
550 // set to -1 (if offset is non-NULL).
551 static bool dll_address_to_function_name(address addr, char* buf,
552 int buflen, int* offset,
553 bool demangle = true);
554
555 // Locate DLL/DSO. On success, full path of the library is copied to
556 // buf, and offset is optionally set to be the distance between addr
557 // and the library's base address. On failure, buf[0] is set to '\0'
558 // and offset is set to -1 (if offset is non-NULL).
559 static bool dll_address_to_library_name(address addr, char* buf,
560 int buflen, int* offset);
561
562 // Find out whether the pc is in the static code for jvm.dll/libjvm.so.
563 static bool address_is_in_vm(address addr);
564
565 // Loads .dll/.so and
566 // in case of error it checks if .dll/.so was built for the
567 // same architecture as HotSpot is running on
568 static void* dll_load(const char *name, char *ebuf, int ebuflen);
569
570 // lookup symbol in a shared library
571 static void* dll_lookup(void* handle, const char* name);
572
573 // Unload library
574 static void dll_unload(void *lib);
575
576 // Callback for loaded module information
577 // Input parameters:
578 // char* module_file_name,
579 // address module_base_addr,
580 // address module_top_addr,
581 // void* param
582 typedef int (*LoadedModulesCallbackFunc)(const char *, address, address, void *);
583
584 static int get_loaded_modules_info(LoadedModulesCallbackFunc callback, void *param);
585
586 // Return the handle of this process
587 static void* get_default_process_handle();
588
589 // Check for static linked agent library
590 static bool find_builtin_agent(AgentLibrary *agent_lib, const char *syms[],
591 size_t syms_len);
592
593 // Find agent entry point
594 static void *find_agent_function(AgentLibrary *agent_lib, bool check_lib,
595 const char *syms[], size_t syms_len);
596
597 // Write to stream
598 static int log_vsnprintf(char* buf, size_t len, const char* fmt, va_list args) ATTRIBUTE_PRINTF(3, 0);
599
600 // Print out system information; they are called by fatal error handler.
601 // Output format may be different on different platforms.
602 static void print_os_info(outputStream* st);
603 static void print_os_info_brief(outputStream* st);
604 static void print_cpu_info(outputStream* st, char* buf, size_t buflen);
605 static void pd_print_cpu_info(outputStream* st, char* buf, size_t buflen);
606 static void print_summary_info(outputStream* st, char* buf, size_t buflen);
607 static void print_memory_info(outputStream* st);
608 static void print_dll_info(outputStream* st);
609 static void print_environment_variables(outputStream* st, const char** env_list);
610 static void print_context(outputStream* st, const void* context);
611 static void print_register_info(outputStream* st, const void* context);
612 static void print_siginfo(outputStream* st, const void* siginfo);
613 static void print_signal_handlers(outputStream* st, char* buf, size_t buflen);
614 static void print_date_and_time(outputStream* st, char* buf, size_t buflen);
615
616 static void print_location(outputStream* st, intptr_t x, bool verbose = false);
617 static size_t lasterror(char *buf, size_t len);
618 static int get_last_error();
619
620 // Determines whether the calling process is being debugged by a user-mode debugger.
621 static bool is_debugger_attached();
622
623 // wait for a key press if PauseAtExit is set
624 static void wait_for_keypress_at_exit(void);
625
626 // The following two functions are used by fatal error handler to trace
627 // native (C) frames. They are not part of frame.hpp/frame.cpp because
628 // frame.hpp/cpp assume thread is JavaThread, and also because different
629 // OS/compiler may have different convention or provide different API to
630 // walk C frames.
631 //
632 // We don't attempt to become a debugger, so we only follow frames if that
633 // does not require a lookup in the unwind table, which is part of the binary
634 // file but may be unsafe to read after a fatal error. So on x86, we can
635 // only walk stack if %ebp is used as frame pointer; on ia64, it's not
636 // possible to walk C stack without having the unwind table.
637 static bool is_first_C_frame(frame *fr);
638 static frame get_sender_for_C_frame(frame *fr);
639
640 // return current frame. pc() and sp() are set to NULL on failure.
641 static frame current_frame();
642
643 static void print_hex_dump(outputStream* st, address start, address end, int unitsize);
644
645 // returns a string to describe the exception/signal;
646 // returns NULL if exception_code is not an OS exception/signal.
647 static const char* exception_name(int exception_code, char* buf, size_t buflen);
648
649 // Returns the signal number (e.g. 11) for a given signal name (SIGSEGV).
650 static int get_signal_number(const char* signal_name);
651
652 // Returns native Java library, loads if necessary
653 static void* native_java_library();
654
655 // Fills in path to jvm.dll/libjvm.so (used by the Disassembler)
656 static void jvm_path(char *buf, jint buflen);
657
658 // Returns true if we are running in a headless jre.
659 static bool is_headless_jre();
660
661 // JNI names
662 static void print_jni_name_prefix_on(outputStream* st, int args_size);
663 static void print_jni_name_suffix_on(outputStream* st, int args_size);
664
665 // Init os specific system properties values
666 static void init_system_properties_values();
667
668 // IO operations, non-JVM_ version.
669 static int stat(const char* path, struct stat* sbuf);
670 static bool dir_is_empty(const char* path);
671
672 // IO operations on binary files
673 static int create_binary_file(const char* path, bool rewrite_existing);
674 static jlong current_file_offset(int fd);
675 static jlong seek_to_file_offset(int fd, jlong offset);
676
677 // Retrieve native stack frames.
678 // Parameter:
679 // stack: an array to storage stack pointers.
680 // frames: size of above array.
681 // toSkip: number of stack frames to skip at the beginning.
682 // Return: number of stack frames captured.
683 static int get_native_stack(address* stack, int size, int toSkip = 0);
684
685 // General allocation (must be MT-safe)
686 static void* malloc (size_t size, MEMFLAGS flags, const NativeCallStack& stack);
687 static void* malloc (size_t size, MEMFLAGS flags);
688 static void* realloc (void *memblock, size_t size, MEMFLAGS flag, const NativeCallStack& stack);
689 static void* realloc (void *memblock, size_t size, MEMFLAGS flag);
690
691 static void free (void *memblock);
692 static bool check_heap(bool force = false); // verify C heap integrity
693 static char* strdup(const char *, MEMFLAGS flags = mtInternal); // Like strdup
694 // Like strdup, but exit VM when strdup() returns NULL
695 static char* strdup_check_oom(const char*, MEMFLAGS flags = mtInternal);
696
697 #ifndef PRODUCT
698 static julong num_mallocs; // # of calls to malloc/realloc
699 static julong alloc_bytes; // # of bytes allocated
700 static julong num_frees; // # of calls to free
701 static julong free_bytes; // # of bytes freed
702 #endif
703
704 // SocketInterface (ex HPI SocketInterface )
705 static int socket(int domain, int type, int protocol);
706 static int socket_close(int fd);
707 static int recv(int fd, char* buf, size_t nBytes, uint flags);
708 static int send(int fd, char* buf, size_t nBytes, uint flags);
709 static int raw_send(int fd, char* buf, size_t nBytes, uint flags);
710 static int connect(int fd, struct sockaddr* him, socklen_t len);
711 static struct hostent* get_host_by_name(char* name);
712
713 // Support for signals (see JVM_RaiseSignal, JVM_RegisterSignal)
714 static void signal_init();
715 static void signal_init_pd();
716 static void signal_notify(int signal_number);
717 static void* signal(int signal_number, void* handler);
718 static void signal_raise(int signal_number);
719 static int signal_wait();
720 static int signal_lookup();
721 static void* user_handler();
722 static void terminate_signal_thread();
723 static int sigexitnum_pd();
724
725 // random number generation
726 static long random(); // return 32bit pseudorandom number
727 static void init_random(long initval); // initialize random sequence
728
729 // Structured OS Exception support
730 static void os_exception_wrapper(java_call_t f, JavaValue* value, const methodHandle& method, JavaCallArguments* args, Thread* thread);
731
732 // On Posix compatible OS it will simply check core dump limits while on Windows
733 // it will check if dump file can be created. Check or prepare a core dump to be
734 // taken at a later point in the same thread in os::abort(). Use the caller
735 // provided buffer as a scratch buffer. The status message which will be written
736 // into the error log either is file location or a short error message, depending
737 // on the checking result.
738 static void check_dump_limit(char* buffer, size_t bufferSize);
739
740 // Get the default path to the core file
741 // Returns the length of the string
742 static int get_core_path(char* buffer, size_t bufferSize);
743
744 // JVMTI & JVM monitoring and management support
745 // The thread_cpu_time() and current_thread_cpu_time() are only
746 // supported if is_thread_cpu_time_supported() returns true.
747 // They are not supported on Solaris T1.
748
749 // Thread CPU Time - return the fast estimate on a platform
750 // On Solaris - call gethrvtime (fast) - user time only
751 // On Linux - fast clock_gettime where available - user+sys
752 // - otherwise: very slow /proc fs - user+sys
753 // On Windows - GetThreadTimes - user+sys
754 static jlong current_thread_cpu_time();
755 static jlong thread_cpu_time(Thread* t);
756
757 // Thread CPU Time with user_sys_cpu_time parameter.
758 //
759 // If user_sys_cpu_time is true, user+sys time is returned.
760 // Otherwise, only user time is returned
761 static jlong current_thread_cpu_time(bool user_sys_cpu_time);
762 static jlong thread_cpu_time(Thread* t, bool user_sys_cpu_time);
763
764 // Return a bunch of info about the timers.
765 // Note that the returned info for these two functions may be different
766 // on some platforms
767 static void current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr);
768 static void thread_cpu_time_info(jvmtiTimerInfo *info_ptr);
769
770 static bool is_thread_cpu_time_supported();
771
772 // System loadavg support. Returns -1 if load average cannot be obtained.
773 static int loadavg(double loadavg[], int nelem);
774
775 // Hook for os specific jvm options that we don't want to abort on seeing
776 static bool obsolete_option(const JavaVMOption *option);
777
778 // Amount beyond the callee frame size that we bang the stack.
779 static int extra_bang_size_in_bytes();
780
781 // Extensions
782 #include "runtime/os_ext.hpp"
783
784 public:
785 class CrashProtectionCallback : public StackObj {
786 public:
787 virtual void call() = 0;
788 };
789
790 // Platform dependent stuff
791 #ifdef TARGET_OS_FAMILY_linux
792 # include "os_linux.hpp"
793 # include "os_posix.hpp"
794 #endif
795 #ifdef TARGET_OS_FAMILY_solaris
796 # include "os_solaris.hpp"
797 # include "os_posix.hpp"
798 #endif
799 #ifdef TARGET_OS_FAMILY_windows
800 # include "os_windows.hpp"
801 #endif
802 #ifdef TARGET_OS_FAMILY_aix
803 # include "os_aix.hpp"
804 # include "os_posix.hpp"
805 #endif
806 #ifdef TARGET_OS_FAMILY_bsd
807 # include "os_posix.hpp"
808 # include "os_bsd.hpp"
809 #endif
810 #ifdef TARGET_OS_ARCH_linux_x86
811 # include "os_linux_x86.hpp"
812 #endif
813 #ifdef TARGET_OS_ARCH_linux_sparc
814 # include "os_linux_sparc.hpp"
815 #endif
816 #ifdef TARGET_OS_ARCH_linux_zero
817 # include "os_linux_zero.hpp"
818 #endif
819 #ifdef TARGET_OS_ARCH_solaris_x86
820 # include "os_solaris_x86.hpp"
821 #endif
822 #ifdef TARGET_OS_ARCH_solaris_sparc
823 # include "os_solaris_sparc.hpp"
824 #endif
825 #ifdef TARGET_OS_ARCH_windows_x86
826 # include "os_windows_x86.hpp"
827 #endif
828 #ifdef TARGET_OS_ARCH_linux_arm
829 # include "os_linux_arm.hpp"
830 #endif
831 #ifdef TARGET_OS_ARCH_linux_ppc
832 # include "os_linux_ppc.hpp"
833 #endif
834 #ifdef TARGET_OS_ARCH_aix_ppc
835 # include "os_aix_ppc.hpp"
836 #endif
837 #ifdef TARGET_OS_ARCH_linux_aarch64
838 # include "os_linux_aarch64.hpp"
839 #endif
840 #ifdef TARGET_OS_ARCH_bsd_x86
841 # include "os_bsd_x86.hpp"
842 #endif
843 #ifdef TARGET_OS_ARCH_bsd_zero
844 # include "os_bsd_zero.hpp"
845 #endif
846
847 #ifndef OS_NATIVE_THREAD_CREATION_FAILED_MSG
848 #define OS_NATIVE_THREAD_CREATION_FAILED_MSG "unable to create native thread: possibly out of memory or process/resource limits reached"
849 #endif
850
851 public:
852 #ifndef PLATFORM_PRINT_NATIVE_STACK
853 // No platform-specific code for printing the native stack.
854 static bool platform_print_native_stack(outputStream* st, const void* context,
855 char *buf, int buf_size) {
856 return false;
857 }
858 #endif
859
860 // debugging support (mostly used by debug.cpp but also fatal error handler)
861 static bool find(address pc, outputStream* st = tty); // OS specific function to make sense out of an address
862
863 static bool dont_yield(); // when true, JVM_Yield() is nop
864 static void print_statistics();
865
866 // Thread priority helpers (implemented in OS-specific part)
867 static OSReturn set_native_priority(Thread* thread, int native_prio);
868 static OSReturn get_native_priority(const Thread* const thread, int* priority_ptr);
869 static int java_to_os_priority[CriticalPriority + 1];
870 // Hint to the underlying OS that a task switch would not be good.
871 // Void return because it's a hint and can fail.
872 static void hint_no_preempt();
873 static const char* native_thread_creation_failed_msg() {
874 return OS_NATIVE_THREAD_CREATION_FAILED_MSG;
875 }
876
877 // Used at creation if requested by the diagnostic flag PauseAtStartup.
878 // Causes the VM to wait until an external stimulus has been applied
879 // (for Unix, that stimulus is a signal, for Windows, an external
880 // ResumeThread call)
881 static void pause();
882
883 // Builds a platform dependent Agent_OnLoad_<libname> function name
884 // which is used to find statically linked in agents.
885 static char* build_agent_function_name(const char *sym, const char *cname,
886 bool is_absolute_path);
887
888 class SuspendedThreadTaskContext {
889 public:
890 SuspendedThreadTaskContext(Thread* thread, void *ucontext) : _thread(thread), _ucontext(ucontext) {}
891 Thread* thread() const { return _thread; }
892 void* ucontext() const { return _ucontext; }
893 private:
894 Thread* _thread;
895 void* _ucontext;
896 };
897
898 class SuspendedThreadTask {
899 public:
900 SuspendedThreadTask(Thread* thread) : _thread(thread), _done(false) {}
901 virtual ~SuspendedThreadTask() {}
902 void run();
903 bool is_done() { return _done; }
904 virtual void do_task(const SuspendedThreadTaskContext& context) = 0;
905 protected:
906 private:
907 void internal_do_task();
908 Thread* _thread;
909 bool _done;
910 };
911
912 #ifndef TARGET_OS_FAMILY_windows
913 // Suspend/resume support
914 // Protocol:
915 //
916 // a thread starts in SR_RUNNING
917 //
918 // SR_RUNNING can go to
919 // * SR_SUSPEND_REQUEST when the WatcherThread wants to suspend it
920 // SR_SUSPEND_REQUEST can go to
921 // * SR_RUNNING if WatcherThread decides it waited for SR_SUSPENDED too long (timeout)
922 // * SR_SUSPENDED if the stopped thread receives the signal and switches state
923 // SR_SUSPENDED can go to
924 // * SR_WAKEUP_REQUEST when the WatcherThread has done the work and wants to resume
925 // SR_WAKEUP_REQUEST can go to
926 // * SR_RUNNING when the stopped thread receives the signal
927 // * SR_WAKEUP_REQUEST on timeout (resend the signal and try again)
928 class SuspendResume {
929 public:
930 enum State {
931 SR_RUNNING,
932 SR_SUSPEND_REQUEST,
933 SR_SUSPENDED,
934 SR_WAKEUP_REQUEST
935 };
936
937 private:
938 volatile State _state;
939
940 private:
941 /* try to switch state from state "from" to state "to"
942 * returns the state set after the method is complete
943 */
944 State switch_state(State from, State to);
945
946 public:
947 SuspendResume() : _state(SR_RUNNING) { }
948
949 State state() const { return _state; }
950
951 State request_suspend() {
952 return switch_state(SR_RUNNING, SR_SUSPEND_REQUEST);
953 }
954
955 State cancel_suspend() {
956 return switch_state(SR_SUSPEND_REQUEST, SR_RUNNING);
957 }
958
959 State suspended() {
960 return switch_state(SR_SUSPEND_REQUEST, SR_SUSPENDED);
961 }
962
963 State request_wakeup() {
964 return switch_state(SR_SUSPENDED, SR_WAKEUP_REQUEST);
965 }
966
967 State running() {
968 return switch_state(SR_WAKEUP_REQUEST, SR_RUNNING);
969 }
970
971 bool is_running() const {
972 return _state == SR_RUNNING;
973 }
974
975 bool is_suspend_request() const {
976 return _state == SR_SUSPEND_REQUEST;
977 }
978
979 bool is_suspended() const {
980 return _state == SR_SUSPENDED;
981 }
982 };
983 #endif
984
985
986 protected:
987 static long _rand_seed; // seed for random number generator
988 static int _processor_count; // number of processors
989
990 static char* format_boot_path(const char* format_string,
991 const char* home,
992 int home_len,
993 char fileSep,
994 char pathSep);
995 static bool set_boot_path(char fileSep, char pathSep);
996 static char** split_path(const char* path, int* n);
997
998 };
999
1000 // Note that "PAUSE" is almost always used with synchronization
1001 // so arguably we should provide Atomic::SpinPause() instead
1002 // of the global SpinPause() with C linkage.
1003 // It'd also be eligible for inlining on many platforms.
1004
1005 extern "C" int SpinPause();
1006
1007 #endif // SHARE_VM_RUNTIME_OS_HPP