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 #ifdef TARGET_OS_FAMILY_linux
32 # include "jvm_linux.h"
33 # include <setjmp.h>
34 #endif
35 #ifdef TARGET_OS_FAMILY_solaris
36 # include "jvm_solaris.h"
37 # include <setjmp.h>
38 #endif
39 #ifdef TARGET_OS_FAMILY_windows
40 # include "jvm_windows.h"
41 #endif
42 #ifdef TARGET_OS_FAMILY_aix
43 # include "jvm_aix.h"
44 # include <setjmp.h>
45 #endif
46 #ifdef TARGET_OS_FAMILY_bsd
47 # include "jvm_bsd.h"
48 # include <setjmp.h>
49 # ifdef __APPLE__
50 # include <mach/mach_time.h>
51 # endif
52 #endif
53
54 class AgentLibrary;
55
56 // os defines the interface to operating system; this includes traditional
57 // OS services (time, I/O) as well as other functionality with system-
58 // dependent code.
59
60 typedef void (*dll_func)(...);
61
62 class Thread;
63 class JavaThread;
64 class Event;
65 class DLL;
66 class FileHandle;
67 class NativeCallStack;
68
69 template<class E> class GrowableArray;
70
71 // %%%%% Moved ThreadState, START_FN, OSThread to new osThread.hpp. -- Rose
72
73 // Platform-independent error return values from OS functions
74 enum OSReturn {
75 OS_OK = 0, // Operation was successful
76 OS_ERR = -1, // Operation failed
77 OS_INTRPT = -2, // Operation was interrupted
78 OS_TIMEOUT = -3, // Operation timed out
79 OS_NOMEM = -5, // Operation failed for lack of memory
80 OS_NORESOURCE = -6 // Operation failed for lack of nonmemory resource
81 };
82
83 enum ThreadPriority { // JLS 20.20.1-3
84 NoPriority = -1, // Initial non-priority value
85 MinPriority = 1, // Minimum priority
86 NormPriority = 5, // Normal (non-daemon) priority
87 NearMaxPriority = 9, // High priority, used for VMThread
88 MaxPriority = 10, // Highest priority, used for WatcherThread
89 // ensures that VMThread doesn't starve profiler
90 CriticalPriority = 11 // Critical thread priority
91 };
92
93 // Executable parameter flag for os::commit_memory() and
94 // os::commit_memory_or_exit().
95 const bool ExecMem = true;
96
97 // Typedef for structured exception handling support
98 typedef void (*java_call_t)(JavaValue* value, const methodHandle& method, JavaCallArguments* args, Thread* thread);
99
100 class MallocTracker;
101
102 class os: AllStatic {
103 friend class VMStructs;
104 friend class JVMCIVMStructs;
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 // Get summary strings for system information in buffer provided
154 static void get_summary_cpu_info(char* buf, size_t buflen);
155 static void get_summary_os_info(char* buf, size_t buflen);
156
157 public:
158 static void init(void); // Called before command line parsing
159 static void init_before_ergo(void); // Called after command line parsing
160 // before VM ergonomics processing.
161 static jint init_2(void); // Called after command line parsing
162 // and VM ergonomics processing
163 static void init_globals(void) { // Called from init_globals() in init.cpp
164 init_globals_ext();
165 }
166
167 // File names are case-insensitive on windows only
168 // Override me as needed
169 static int file_name_strcmp(const char* s1, const char* s2);
170
171 // unset environment variable
172 static bool unsetenv(const char* name);
173
174 static bool have_special_privileges();
175
176 static jlong javaTimeMillis();
177 static jlong javaTimeNanos();
178 static void javaTimeNanos_info(jvmtiTimerInfo *info_ptr);
179 static void javaTimeSystemUTC(jlong &seconds, jlong &nanos);
180 static void run_periodic_checks();
181 static bool supports_monotonic_clock();
182
183 // Returns the elapsed time in seconds since the vm started.
184 static double elapsedTime();
185
186 // Returns real time in seconds since an arbitrary point
187 // in the past.
188 static bool getTimesSecs(double* process_real_time,
189 double* process_user_time,
190 double* process_system_time);
191
192 // Interface to the performance counter
193 static jlong elapsed_counter();
194 static jlong elapsed_frequency();
195
196 // The "virtual time" of a thread is the amount of time a thread has
197 // actually run. The first function indicates whether the OS supports
198 // this functionality for the current thread, and if so:
199 // * the second enables vtime tracking (if that is required).
200 // * the third tells whether vtime is enabled.
201 // * the fourth returns the elapsed virtual time for the current
202 // thread.
203 static bool supports_vtime();
204 static bool enable_vtime();
205 static bool vtime_enabled();
206 static double elapsedVTime();
207
208 // Return current local time in a string (YYYY-MM-DD HH:MM:SS).
209 // It is MT safe, but not async-safe, as reading time zone
210 // information may require a lock on some platforms.
211 static char* local_time_string(char *buf, size_t buflen);
212 static struct tm* localtime_pd (const time_t* clock, struct tm* res);
213 // Fill in buffer with current local time as an ISO-8601 string.
214 // E.g., YYYY-MM-DDThh:mm:ss.mmm+zzzz.
215 // Returns buffer, or NULL if it failed.
216 static char* iso8601_time(char* buffer, size_t buffer_length);
217
218 // Interface for detecting multiprocessor system
219 static inline bool is_MP() {
220 // During bootstrap if _processor_count is not yet initialized
221 // we claim to be MP as that is safest. If any platform has a
222 // stub generator that might be triggered in this phase and for
223 // which being declared MP when in fact not, is a problem - then
224 // the bootstrap routine for the stub generator needs to check
225 // the processor count directly and leave the bootstrap routine
226 // in place until called after initialization has ocurred.
227 return (_processor_count != 1) || AssumeMP;
228 }
229 static julong available_memory();
230 static julong physical_memory();
231 static bool has_allocatable_memory_limit(julong* limit);
232 static bool is_server_class_machine();
233
234 // number of CPUs
235 static int processor_count() {
236 return _processor_count;
237 }
238 static void set_processor_count(int count) { _processor_count = count; }
239
240 // Returns the number of CPUs this process is currently allowed to run on.
241 // Note that on some OSes this can change dynamically.
242 static int active_processor_count();
243
244 // Bind processes to processors.
245 // This is a two step procedure:
246 // first you generate a distribution of processes to processors,
247 // then you bind processes according to that distribution.
248 // Compute a distribution for number of processes to processors.
249 // Stores the processor id's into the distribution array argument.
250 // Returns true if it worked, false if it didn't.
251 static bool distribute_processes(uint length, uint* distribution);
252 // Binds the current process to a processor.
253 // Returns true if it worked, false if it didn't.
254 static bool bind_to_processor(uint processor_id);
255
256 // Give a name to the current thread.
257 static void set_native_thread_name(const char *name);
258
259 // Interface for stack banging (predetect possible stack overflow for
260 // exception processing) There are guard pages, and above that shadow
261 // pages for stack overflow checking.
262 static bool uses_stack_guard_pages();
263 static bool allocate_stack_guard_pages();
264 static void map_stack_shadow_pages();
265 static bool stack_shadow_pages_available(Thread *thread, const methodHandle& method);
266
267 // OS interface to Virtual Memory
268
269 // Return the default page size.
270 static int vm_page_size();
271
272 // Returns the page size to use for a region of memory.
273 // region_size / min_pages will always be greater than or equal to the
274 // returned value. The returned value will divide region_size.
275 static size_t page_size_for_region_aligned(size_t region_size, size_t min_pages);
276
277 // Returns the page size to use for a region of memory.
278 // region_size / min_pages will always be greater than or equal to the
279 // returned value. The returned value might not divide region_size.
280 static size_t page_size_for_region_unaligned(size_t region_size, size_t min_pages);
281
282 // Return the largest page size that can be used
283 static size_t max_page_size() {
284 // The _page_sizes array is sorted in descending order.
285 return _page_sizes[0];
286 }
287
288 // Methods for tracing page sizes returned by the above method.
289 // The region_{min,max}_size parameters should be the values
290 // passed to page_size_for_region() and page_size should be the result of that
291 // call. The (optional) base and size parameters should come from the
292 // ReservedSpace base() and size() methods.
293 static void trace_page_sizes(const char* str, const size_t* page_sizes, int count);
294 static void trace_page_sizes(const char* str,
295 const size_t region_min_size,
296 const size_t region_max_size,
297 const size_t page_size,
298 const char* base,
299 const size_t size);
300 static void trace_page_sizes_for_requested_size(const char* str,
301 const size_t requested_size,
302 const size_t page_size,
303 const size_t alignment,
304 const char* base,
305 const size_t size);
306
307 static int vm_allocation_granularity();
308 static char* reserve_memory(size_t bytes, char* addr = 0,
309 size_t alignment_hint = 0);
310 static char* reserve_memory(size_t bytes, char* addr,
311 size_t alignment_hint, MEMFLAGS flags);
312 static char* reserve_memory_aligned(size_t size, size_t alignment);
313 static char* attempt_reserve_memory_at(size_t bytes, char* addr);
314 static void split_reserved_memory(char *base, size_t size,
315 size_t split, bool realloc);
316 static bool commit_memory(char* addr, size_t bytes, bool executable);
317 static bool commit_memory(char* addr, size_t size, size_t alignment_hint,
318 bool executable);
319 // Same as commit_memory() that either succeeds or calls
320 // vm_exit_out_of_memory() with the specified mesg.
321 static void commit_memory_or_exit(char* addr, size_t bytes,
322 bool executable, const char* mesg);
323 static void commit_memory_or_exit(char* addr, size_t size,
324 size_t alignment_hint,
325 bool executable, const char* mesg);
326 static bool uncommit_memory(char* addr, size_t bytes);
327 static bool release_memory(char* addr, size_t bytes);
328
329 // Touch memory pages that cover the memory range from start to end (exclusive)
330 // to make the OS back the memory range with actual memory.
331 // Current implementation may not touch the last page if unaligned addresses
332 // are passed.
333 static void pretouch_memory(void* start, void* end);
334
335 enum ProtType { MEM_PROT_NONE, MEM_PROT_READ, MEM_PROT_RW, MEM_PROT_RWX };
336 static bool protect_memory(char* addr, size_t bytes, ProtType prot,
337 bool is_committed = true);
338
339 static bool guard_memory(char* addr, size_t bytes);
340 static bool unguard_memory(char* addr, size_t bytes);
341 static bool create_stack_guard_pages(char* addr, size_t bytes);
342 static bool pd_create_stack_guard_pages(char* addr, size_t bytes);
343 static bool remove_stack_guard_pages(char* addr, size_t bytes);
344
345 static char* map_memory(int fd, const char* file_name, size_t file_offset,
346 char *addr, size_t bytes, bool read_only = false,
347 bool allow_exec = false);
348 static char* remap_memory(int fd, const char* file_name, size_t file_offset,
349 char *addr, size_t bytes, bool read_only,
350 bool allow_exec);
351 static bool unmap_memory(char *addr, size_t bytes);
352 static void free_memory(char *addr, size_t bytes, size_t alignment_hint);
353 static void realign_memory(char *addr, size_t bytes, size_t alignment_hint);
354
355 // NUMA-specific interface
356 static bool numa_has_static_binding();
357 static bool numa_has_group_homing();
358 static void numa_make_local(char *addr, size_t bytes, int lgrp_hint);
359 static void numa_make_global(char *addr, size_t bytes);
360 static size_t numa_get_groups_num();
361 static size_t numa_get_leaf_groups(int *ids, size_t size);
362 static bool numa_topology_changed();
363 static int numa_get_group_id();
364
365 // Page manipulation
366 struct page_info {
367 size_t size;
368 int lgrp_id;
369 };
370 static bool get_page_info(char *start, page_info* info);
371 static char* scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found);
372
373 static char* non_memory_address_word();
374 // reserve, commit and pin the entire memory region
375 static char* reserve_memory_special(size_t size, size_t alignment,
376 char* addr, bool executable);
377 static bool release_memory_special(char* addr, size_t bytes);
378 static void large_page_init();
379 static size_t large_page_size();
380 static bool can_commit_large_page_memory();
381 static bool can_execute_large_page_memory();
382
383 // OS interface to polling page
384 static address get_polling_page() { return _polling_page; }
385 static void set_polling_page(address page) { _polling_page = page; }
386 static bool is_poll_address(address addr) { return addr >= _polling_page && addr < (_polling_page + os::vm_page_size()); }
387 static void make_polling_page_unreadable();
388 static void make_polling_page_readable();
389
390 // Routines used to serialize the thread state without using membars
391 static void serialize_thread_states();
392
393 // Since we write to the serialize page from every thread, we
394 // want stores to be on unique cache lines whenever possible
395 // in order to minimize CPU cross talk. We pre-compute the
396 // amount to shift the thread* to make this offset unique to
397 // each thread.
398 static int get_serialize_page_shift_count() {
399 return SerializePageShiftCount;
400 }
401
402 static void set_serialize_page_mask(uintptr_t mask) {
403 _serialize_page_mask = mask;
404 }
405
406 static unsigned int get_serialize_page_mask() {
407 return _serialize_page_mask;
408 }
409
410 static void set_memory_serialize_page(address page);
411
412 static address get_memory_serialize_page() {
413 return (address)_mem_serialize_page;
414 }
415
416 static inline void write_memory_serialize_page(JavaThread *thread) {
417 uintptr_t page_offset = ((uintptr_t)thread >>
418 get_serialize_page_shift_count()) &
419 get_serialize_page_mask();
420 *(volatile int32_t *)((uintptr_t)_mem_serialize_page+page_offset) = 1;
421 }
422
423 static bool is_memory_serialize_page(JavaThread *thread, address addr) {
424 if (UseMembar) return false;
425 // Previously this function calculated the exact address of this
426 // thread's serialize page, and checked if the faulting address
427 // was equal. However, some platforms mask off faulting addresses
428 // to the page size, so now we just check that the address is
429 // within the page. This makes the thread argument unnecessary,
430 // but we retain the NULL check to preserve existing behavior.
431 if (thread == NULL) return false;
432 address page = (address) _mem_serialize_page;
433 return addr >= page && addr < (page + os::vm_page_size());
434 }
435
436 static void block_on_serialize_page_trap();
437
438 // threads
439
440 enum ThreadType {
441 vm_thread,
442 cgc_thread, // Concurrent GC thread
443 pgc_thread, // Parallel GC thread
444 java_thread,
445 compiler_thread,
446 watcher_thread,
447 os_thread
448 };
449
450 static bool create_thread(Thread* thread,
451 ThreadType thr_type,
452 size_t stack_size = 0);
453 static bool create_main_thread(JavaThread* thread);
454 static bool create_attached_thread(JavaThread* thread);
455 static void pd_start_thread(Thread* thread);
456 static void start_thread(Thread* thread);
457
458 static void initialize_thread(Thread* thr);
459 static void free_thread(OSThread* osthread);
460
461 // thread id on Linux/64bit is 64bit, on Windows and Solaris, it's 32bit
462 static intx current_thread_id();
463 static int current_process_id();
464 static int sleep(Thread* thread, jlong ms, bool interruptable);
465 // Short standalone OS sleep suitable for slow path spin loop.
466 // Ignores Thread.interrupt() (so keep it short).
467 // ms = 0, will sleep for the least amount of time allowed by the OS.
468 static void naked_short_sleep(jlong ms);
469 static void infinite_sleep(); // never returns, use with CAUTION
470 static void naked_yield () ;
471 static OSReturn set_priority(Thread* thread, ThreadPriority priority);
472 static OSReturn get_priority(const Thread* const thread, ThreadPriority& priority);
473
474 static void interrupt(Thread* thread);
475 static bool is_interrupted(Thread* thread, bool clear_interrupted);
476
477 static int pd_self_suspend_thread(Thread* thread);
478
479 static ExtendedPC fetch_frame_from_context(const void* ucVoid, intptr_t** sp, intptr_t** fp);
480 static frame fetch_frame_from_context(const void* ucVoid);
481 static frame fetch_frame_from_ucontext(Thread* thread, void* ucVoid);
482
483 static ExtendedPC get_thread_pc(Thread *thread);
484 static void breakpoint();
485 static bool start_debugging(char *buf, int buflen);
486
487 static address current_stack_pointer();
488 static address current_stack_base();
489 static size_t current_stack_size();
490
491 static void verify_stack_alignment() PRODUCT_RETURN;
492
493 static bool message_box(const char* title, const char* message);
494 static char* do_you_want_to_debug(const char* message);
495
496 // run cmd in a separate process and return its exit code; or -1 on failures
497 static int fork_and_exec(char *cmd);
498
499 // Call ::exit() on all platforms but Windows
500 static void exit(int num);
501
502 // Terminate the VM, but don't exit the process
503 static void shutdown();
504
505 // Terminate with an error. Default is to generate a core file on platforms
506 // that support such things. This calls shutdown() and then aborts.
507 static void abort(bool dump_core, void *siginfo, const void *context);
508 static void abort(bool dump_core = true);
509
510 // Die immediately, no exit hook, no abort hook, no cleanup.
511 static void die();
512
513 // File i/o operations
514 static const int default_file_open_flags();
515 static int open(const char *path, int oflag, int mode);
516 static FILE* open(int fd, const char* mode);
517 static int close(int fd);
518 static jlong lseek(int fd, jlong offset, int whence);
519 static char* native_path(char *path);
520 static int ftruncate(int fd, jlong length);
521 static int fsync(int fd);
522 static int available(int fd, jlong *bytes);
523 static int get_fileno(FILE* fp);
524 static void flockfile(FILE* fp);
525 static void funlockfile(FILE* fp);
526
527 static int compare_file_modified_times(const char* file1, const char* file2);
528
529 //File i/o operations
530
531 static size_t read(int fd, void *buf, unsigned int nBytes);
532 static size_t read_at(int fd, void *buf, unsigned int nBytes, jlong offset);
533 static size_t restartable_read(int fd, void *buf, unsigned int nBytes);
534 static size_t write(int fd, const void *buf, unsigned int nBytes);
535
536 // Reading directories.
537 static DIR* opendir(const char* dirname);
538 static int readdir_buf_size(const char *path);
539 static struct dirent* readdir(DIR* dirp, dirent* dbuf);
540 static int closedir(DIR* dirp);
541
542 // Dynamic library extension
543 static const char* dll_file_extension();
544
545 static const char* get_temp_directory();
546 static const char* get_current_directory(char *buf, size_t buflen);
547
548 // Builds a platform-specific full library path given a ld path and lib name
549 // Returns true if buffer contains full path to existing file, false otherwise
550 static bool dll_build_name(char* buffer, size_t size,
551 const char* pathname, const char* fname);
552
553 // Symbol lookup, find nearest function name; basically it implements
554 // dladdr() for all platforms. Name of the nearest function is copied
555 // to buf. Distance from its base address is optionally returned as offset.
556 // If function name is not found, buf[0] is set to '\0' and offset is
557 // set to -1 (if offset is non-NULL).
558 static bool dll_address_to_function_name(address addr, char* buf,
559 int buflen, int* offset,
560 bool demangle = true);
561
562 // Locate DLL/DSO. On success, full path of the library is copied to
563 // buf, and offset is optionally set to be the distance between addr
564 // and the library's base address. On failure, buf[0] is set to '\0'
565 // and offset is set to -1 (if offset is non-NULL).
566 static bool dll_address_to_library_name(address addr, char* buf,
567 int buflen, int* offset);
568
569 // Find out whether the pc is in the static code for jvm.dll/libjvm.so.
570 static bool address_is_in_vm(address addr);
571
572 // Loads .dll/.so and
573 // in case of error it checks if .dll/.so was built for the
574 // same architecture as HotSpot is running on
575 static void* dll_load(const char *name, char *ebuf, int ebuflen);
576
577 // lookup symbol in a shared library
578 static void* dll_lookup(void* handle, const char* name);
579
580 // Unload library
581 static void dll_unload(void *lib);
582
583 // Callback for loaded module information
584 // Input parameters:
585 // char* module_file_name,
586 // address module_base_addr,
587 // address module_top_addr,
588 // void* param
589 typedef int (*LoadedModulesCallbackFunc)(const char *, address, address, void *);
590
591 static int get_loaded_modules_info(LoadedModulesCallbackFunc callback, void *param);
592
593 // Return the handle of this process
594 static void* get_default_process_handle();
595
596 // Check for static linked agent library
597 static bool find_builtin_agent(AgentLibrary *agent_lib, const char *syms[],
598 size_t syms_len);
599
600 // Find agent entry point
601 static void *find_agent_function(AgentLibrary *agent_lib, bool check_lib,
602 const char *syms[], size_t syms_len);
603
604 // Write to stream
605 static int log_vsnprintf(char* buf, size_t len, const char* fmt, va_list args) ATTRIBUTE_PRINTF(3, 0);
606
607 // Get host name in buffer provided
608 static bool get_host_name(char* buf, size_t buflen);
609
610 // Print out system information; they are called by fatal error handler.
611 // Output format may be different on different platforms.
612 static void print_os_info(outputStream* st);
613 static void print_os_info_brief(outputStream* st);
614 static void print_cpu_info(outputStream* st, char* buf, size_t buflen);
615 static void pd_print_cpu_info(outputStream* st, char* buf, size_t buflen);
616 static void print_summary_info(outputStream* st, char* buf, size_t buflen);
617 static void print_memory_info(outputStream* st);
618 static void print_dll_info(outputStream* st);
619 static void print_environment_variables(outputStream* st, const char** env_list);
620 static void print_context(outputStream* st, const void* context);
621 static void print_register_info(outputStream* st, const void* context);
622 static void print_siginfo(outputStream* st, const void* siginfo);
623 static void print_signal_handlers(outputStream* st, char* buf, size_t buflen);
624 static void print_date_and_time(outputStream* st, char* buf, size_t buflen);
625
626 static void print_location(outputStream* st, intptr_t x, bool verbose = false);
627 static size_t lasterror(char *buf, size_t len);
628 static int get_last_error();
629
630 // Replacement for strerror().
631 // Will return the english description of the error (e.g. "File not found", as
632 // suggested in the POSIX standard.
633 // Will return "Unknown error" for an unknown errno value.
634 // Will not attempt to localize the returned string.
635 // Will always return a valid string which is a static constant.
636 // Will not change the value of errno.
637 static const char* strerror(int e);
638
639 // Will return the literalized version of the given errno (e.g. "EINVAL"
640 // for EINVAL).
641 // Will return "Unknown error" for an unknown errno value.
642 // Will always return a valid string which is a static constant.
643 // Will not change the value of errno.
644 static const char* errno_name(int e);
645
646 // Determines whether the calling process is being debugged by a user-mode debugger.
647 static bool is_debugger_attached();
648
649 // wait for a key press if PauseAtExit is set
650 static void wait_for_keypress_at_exit(void);
651
652 // The following two functions are used by fatal error handler to trace
653 // native (C) frames. They are not part of frame.hpp/frame.cpp because
654 // frame.hpp/cpp assume thread is JavaThread, and also because different
655 // OS/compiler may have different convention or provide different API to
656 // walk C frames.
657 //
658 // We don't attempt to become a debugger, so we only follow frames if that
659 // does not require a lookup in the unwind table, which is part of the binary
660 // file but may be unsafe to read after a fatal error. So on x86, we can
661 // only walk stack if %ebp is used as frame pointer; on ia64, it's not
662 // possible to walk C stack without having the unwind table.
663 static bool is_first_C_frame(frame *fr);
664 static frame get_sender_for_C_frame(frame *fr);
665
666 // return current frame. pc() and sp() are set to NULL on failure.
667 static frame current_frame();
668
669 static void print_hex_dump(outputStream* st, address start, address end, int unitsize);
670
671 // returns a string to describe the exception/signal;
672 // returns NULL if exception_code is not an OS exception/signal.
673 static const char* exception_name(int exception_code, char* buf, size_t buflen);
674
675 // Returns the signal number (e.g. 11) for a given signal name (SIGSEGV).
676 static int get_signal_number(const char* signal_name);
677
678 // Returns native Java library, loads if necessary
679 static void* native_java_library();
680
681 // Fills in path to jvm.dll/libjvm.so (used by the Disassembler)
682 static void jvm_path(char *buf, jint buflen);
683
684 // Returns true if we are running in a headless jre.
685 static bool is_headless_jre();
686
687 // JNI names
688 static void print_jni_name_prefix_on(outputStream* st, int args_size);
689 static void print_jni_name_suffix_on(outputStream* st, int args_size);
690
691 // Init os specific system properties values
692 static void init_system_properties_values();
693
694 // IO operations, non-JVM_ version.
695 static int stat(const char* path, struct stat* sbuf);
696 static bool dir_is_empty(const char* path);
697
698 // IO operations on binary files
699 static int create_binary_file(const char* path, bool rewrite_existing);
700 static jlong current_file_offset(int fd);
701 static jlong seek_to_file_offset(int fd, jlong offset);
702
703 // Retrieve native stack frames.
704 // Parameter:
705 // stack: an array to storage stack pointers.
706 // frames: size of above array.
707 // toSkip: number of stack frames to skip at the beginning.
708 // Return: number of stack frames captured.
709 static int get_native_stack(address* stack, int size, int toSkip = 0);
710
711 // General allocation (must be MT-safe)
712 static void* malloc (size_t size, MEMFLAGS flags, const NativeCallStack& stack);
713 static void* malloc (size_t size, MEMFLAGS flags);
714 static void* realloc (void *memblock, size_t size, MEMFLAGS flag, const NativeCallStack& stack);
715 static void* realloc (void *memblock, size_t size, MEMFLAGS flag);
716
717 static void free (void *memblock);
718 static bool check_heap(bool force = false); // verify C heap integrity
719 static char* strdup(const char *, MEMFLAGS flags = mtInternal); // Like strdup
720 // Like strdup, but exit VM when strdup() returns NULL
721 static char* strdup_check_oom(const char*, MEMFLAGS flags = mtInternal);
722
723 #ifndef PRODUCT
724 static julong num_mallocs; // # of calls to malloc/realloc
725 static julong alloc_bytes; // # of bytes allocated
726 static julong num_frees; // # of calls to free
727 static julong free_bytes; // # of bytes freed
728 #endif
729
730 // SocketInterface (ex HPI SocketInterface )
731 static int socket(int domain, int type, int protocol);
732 static int socket_close(int fd);
733 static int recv(int fd, char* buf, size_t nBytes, uint flags);
734 static int send(int fd, char* buf, size_t nBytes, uint flags);
735 static int raw_send(int fd, char* buf, size_t nBytes, uint flags);
736 static int connect(int fd, struct sockaddr* him, socklen_t len);
737 static struct hostent* get_host_by_name(char* name);
738
739 // Support for signals (see JVM_RaiseSignal, JVM_RegisterSignal)
740 static void signal_init();
741 static void signal_init_pd();
742 static void signal_notify(int signal_number);
743 static void* signal(int signal_number, void* handler);
744 static void signal_raise(int signal_number);
745 static int signal_wait();
746 static int signal_lookup();
747 static void* user_handler();
748 static void terminate_signal_thread();
749 static int sigexitnum_pd();
750
751 // random number generation
752 static long random(); // return 32bit pseudorandom number
753 static void init_random(long initval); // initialize random sequence
754
755 // Structured OS Exception support
756 static void os_exception_wrapper(java_call_t f, JavaValue* value, const methodHandle& method, JavaCallArguments* args, Thread* thread);
757
758 // On Posix compatible OS it will simply check core dump limits while on Windows
759 // it will check if dump file can be created. Check or prepare a core dump to be
760 // taken at a later point in the same thread in os::abort(). Use the caller
761 // provided buffer as a scratch buffer. The status message which will be written
762 // into the error log either is file location or a short error message, depending
763 // on the checking result.
764 static void check_dump_limit(char* buffer, size_t bufferSize);
765
766 // Get the default path to the core file
767 // Returns the length of the string
768 static int get_core_path(char* buffer, size_t bufferSize);
769
770 // JVMTI & JVM monitoring and management support
771 // The thread_cpu_time() and current_thread_cpu_time() are only
772 // supported if is_thread_cpu_time_supported() returns true.
773 // They are not supported on Solaris T1.
774
775 // Thread CPU Time - return the fast estimate on a platform
776 // On Solaris - call gethrvtime (fast) - user time only
777 // On Linux - fast clock_gettime where available - user+sys
778 // - otherwise: very slow /proc fs - user+sys
779 // On Windows - GetThreadTimes - user+sys
780 static jlong current_thread_cpu_time();
781 static jlong thread_cpu_time(Thread* t);
782
783 // Thread CPU Time with user_sys_cpu_time parameter.
784 //
785 // If user_sys_cpu_time is true, user+sys time is returned.
786 // Otherwise, only user time is returned
787 static jlong current_thread_cpu_time(bool user_sys_cpu_time);
788 static jlong thread_cpu_time(Thread* t, bool user_sys_cpu_time);
789
790 // Return a bunch of info about the timers.
791 // Note that the returned info for these two functions may be different
792 // on some platforms
793 static void current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr);
794 static void thread_cpu_time_info(jvmtiTimerInfo *info_ptr);
795
796 static bool is_thread_cpu_time_supported();
797
798 // System loadavg support. Returns -1 if load average cannot be obtained.
799 static int loadavg(double loadavg[], int nelem);
800
801 // Hook for os specific jvm options that we don't want to abort on seeing
802 static bool obsolete_option(const JavaVMOption *option);
803
804 // Amount beyond the callee frame size that we bang the stack.
805 static int extra_bang_size_in_bytes();
806
807 static char** split_path(const char* path, int* n);
808
809 // Extensions
810 #include "runtime/os_ext.hpp"
811
812 public:
813 class CrashProtectionCallback : public StackObj {
814 public:
815 virtual void call() = 0;
816 };
817
818 // Platform dependent stuff
819 #ifdef TARGET_OS_FAMILY_linux
820 # include "os_linux.hpp"
821 # include "os_posix.hpp"
822 #endif
823 #ifdef TARGET_OS_FAMILY_solaris
824 # include "os_solaris.hpp"
825 # include "os_posix.hpp"
826 #endif
827 #ifdef TARGET_OS_FAMILY_windows
828 # include "os_windows.hpp"
829 #endif
830 #ifdef TARGET_OS_FAMILY_aix
831 # include "os_aix.hpp"
832 # include "os_posix.hpp"
833 #endif
834 #ifdef TARGET_OS_FAMILY_bsd
835 # include "os_posix.hpp"
836 # include "os_bsd.hpp"
837 #endif
838 #ifdef TARGET_OS_ARCH_linux_x86
839 # include "os_linux_x86.hpp"
840 #endif
841 #ifdef TARGET_OS_ARCH_linux_sparc
842 # include "os_linux_sparc.hpp"
843 #endif
844 #ifdef TARGET_OS_ARCH_linux_zero
845 # include "os_linux_zero.hpp"
846 #endif
847 #ifdef TARGET_OS_ARCH_solaris_x86
848 # include "os_solaris_x86.hpp"
849 #endif
850 #ifdef TARGET_OS_ARCH_solaris_sparc
851 # include "os_solaris_sparc.hpp"
852 #endif
853 #ifdef TARGET_OS_ARCH_windows_x86
854 # include "os_windows_x86.hpp"
855 #endif
856 #ifdef TARGET_OS_ARCH_linux_arm
857 # include "os_linux_arm.hpp"
858 #endif
859 #ifdef TARGET_OS_ARCH_linux_ppc
860 # include "os_linux_ppc.hpp"
861 #endif
862 #ifdef TARGET_OS_ARCH_aix_ppc
863 # include "os_aix_ppc.hpp"
864 #endif
865 #ifdef TARGET_OS_ARCH_linux_aarch64
866 # include "os_linux_aarch64.hpp"
867 #endif
868 #ifdef TARGET_OS_ARCH_bsd_x86
869 # include "os_bsd_x86.hpp"
870 #endif
871 #ifdef TARGET_OS_ARCH_bsd_zero
872 # include "os_bsd_zero.hpp"
873 #endif
874
875 #ifndef OS_NATIVE_THREAD_CREATION_FAILED_MSG
876 #define OS_NATIVE_THREAD_CREATION_FAILED_MSG "unable to create native thread: possibly out of memory or process/resource limits reached"
877 #endif
878
879 public:
880 #ifndef PLATFORM_PRINT_NATIVE_STACK
881 // No platform-specific code for printing the native stack.
882 static bool platform_print_native_stack(outputStream* st, const void* context,
883 char *buf, int buf_size) {
884 return false;
885 }
886 #endif
887
888 // debugging support (mostly used by debug.cpp but also fatal error handler)
889 static bool find(address pc, outputStream* st = tty); // OS specific function to make sense out of an address
890
891 static bool dont_yield(); // when true, JVM_Yield() is nop
892 static void print_statistics();
893
894 // Thread priority helpers (implemented in OS-specific part)
895 static OSReturn set_native_priority(Thread* thread, int native_prio);
896 static OSReturn get_native_priority(const Thread* const thread, int* priority_ptr);
897 static int java_to_os_priority[CriticalPriority + 1];
898 // Hint to the underlying OS that a task switch would not be good.
899 // Void return because it's a hint and can fail.
900 static void hint_no_preempt();
901 static const char* native_thread_creation_failed_msg() {
902 return OS_NATIVE_THREAD_CREATION_FAILED_MSG;
903 }
904
905 // Used at creation if requested by the diagnostic flag PauseAtStartup.
906 // Causes the VM to wait until an external stimulus has been applied
907 // (for Unix, that stimulus is a signal, for Windows, an external
908 // ResumeThread call)
909 static void pause();
910
911 // Builds a platform dependent Agent_OnLoad_<libname> function name
912 // which is used to find statically linked in agents.
913 static char* build_agent_function_name(const char *sym, const char *cname,
914 bool is_absolute_path);
915
916 class SuspendedThreadTaskContext {
917 public:
918 SuspendedThreadTaskContext(Thread* thread, void *ucontext) : _thread(thread), _ucontext(ucontext) {}
919 Thread* thread() const { return _thread; }
920 void* ucontext() const { return _ucontext; }
921 private:
922 Thread* _thread;
923 void* _ucontext;
924 };
925
926 class SuspendedThreadTask {
927 public:
928 SuspendedThreadTask(Thread* thread) : _thread(thread), _done(false) {}
929 virtual ~SuspendedThreadTask() {}
930 void run();
931 bool is_done() { return _done; }
932 virtual void do_task(const SuspendedThreadTaskContext& context) = 0;
933 protected:
934 private:
935 void internal_do_task();
936 Thread* _thread;
937 bool _done;
938 };
939
940 #ifndef TARGET_OS_FAMILY_windows
941 // Suspend/resume support
942 // Protocol:
943 //
944 // a thread starts in SR_RUNNING
945 //
946 // SR_RUNNING can go to
947 // * SR_SUSPEND_REQUEST when the WatcherThread wants to suspend it
948 // SR_SUSPEND_REQUEST can go to
949 // * SR_RUNNING if WatcherThread decides it waited for SR_SUSPENDED too long (timeout)
950 // * SR_SUSPENDED if the stopped thread receives the signal and switches state
951 // SR_SUSPENDED can go to
952 // * SR_WAKEUP_REQUEST when the WatcherThread has done the work and wants to resume
953 // SR_WAKEUP_REQUEST can go to
954 // * SR_RUNNING when the stopped thread receives the signal
955 // * SR_WAKEUP_REQUEST on timeout (resend the signal and try again)
956 class SuspendResume {
957 public:
958 enum State {
959 SR_RUNNING,
960 SR_SUSPEND_REQUEST,
961 SR_SUSPENDED,
962 SR_WAKEUP_REQUEST
963 };
964
965 private:
966 volatile State _state;
967
968 private:
969 /* try to switch state from state "from" to state "to"
970 * returns the state set after the method is complete
971 */
972 State switch_state(State from, State to);
973
974 public:
975 SuspendResume() : _state(SR_RUNNING) { }
976
977 State state() const { return _state; }
978
979 State request_suspend() {
980 return switch_state(SR_RUNNING, SR_SUSPEND_REQUEST);
981 }
982
983 State cancel_suspend() {
984 return switch_state(SR_SUSPEND_REQUEST, SR_RUNNING);
985 }
986
987 State suspended() {
988 return switch_state(SR_SUSPEND_REQUEST, SR_SUSPENDED);
989 }
990
991 State request_wakeup() {
992 return switch_state(SR_SUSPENDED, SR_WAKEUP_REQUEST);
993 }
994
995 State running() {
996 return switch_state(SR_WAKEUP_REQUEST, SR_RUNNING);
997 }
998
999 bool is_running() const {
1000 return _state == SR_RUNNING;
1001 }
1002
1003 bool is_suspend_request() const {
1004 return _state == SR_SUSPEND_REQUEST;
1005 }
1006
1007 bool is_suspended() const {
1008 return _state == SR_SUSPENDED;
1009 }
1010 };
1011 #endif
1012
1013
1014 protected:
1015 static long _rand_seed; // seed for random number generator
1016 static int _processor_count; // number of processors
1017
1018 static char* format_boot_path(const char* format_string,
1019 const char* home,
1020 int home_len,
1021 char fileSep,
1022 char pathSep);
1023 static bool set_boot_path(char fileSep, char pathSep);
1024
1025 };
1026
1027 // Note that "PAUSE" is almost always used with synchronization
1028 // so arguably we should provide Atomic::SpinPause() instead
1029 // of the global SpinPause() with C linkage.
1030 // It'd also be eligible for inlining on many platforms.
1031
1032 extern "C" int SpinPause();
1033
1034 #endif // SHARE_VM_RUNTIME_OS_HPP