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, int file_desc = -1);
125 static char* pd_attempt_reserve_memory_at(size_t bytes, char* addr, int file_desc = -1);
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, int file_desc = -1);
310 static char* reserve_memory(size_t bytes, int file_desc);
311 static char* reserve_memory(size_t bytes, char* addr,
312 size_t alignment_hint, MEMFLAGS flags);
313 static char* reserve_memory_aligned(size_t size, size_t alignment, int file_desc = -1);
314 static char* attempt_reserve_memory_at(size_t bytes, char* addr, int file_desc = -1);
315
316 static void split_reserved_memory(char *base, size_t size,
317 size_t split, bool realloc);
318 static bool commit_memory(char* addr, size_t bytes, bool executable);
319 static bool commit_memory(char* addr, size_t size, size_t alignment_hint,
320 bool executable);
321 // Same as commit_memory() that either succeeds or calls
322 // vm_exit_out_of_memory() with the specified mesg.
323 static void commit_memory_or_exit(char* addr, size_t bytes,
324 bool executable, const char* mesg);
325 static void commit_memory_or_exit(char* addr, size_t size,
326 size_t alignment_hint,
327 bool executable, const char* mesg);
328 static bool uncommit_memory(char* addr, size_t bytes);
329 static bool release_memory(char* addr, size_t bytes);
330
331 // Touch memory pages that cover the memory range from start to end (exclusive)
332 // to make the OS back the memory range with actual memory.
333 // Current implementation may not touch the last page if unaligned addresses
334 // are passed.
335 static void pretouch_memory(void* start, void* end);
336
337 enum ProtType { MEM_PROT_NONE, MEM_PROT_READ, MEM_PROT_RW, MEM_PROT_RWX };
338 static bool protect_memory(char* addr, size_t bytes, ProtType prot,
339 bool is_committed = true);
340
341 static bool guard_memory(char* addr, size_t bytes);
342 static bool unguard_memory(char* addr, size_t bytes);
343 static bool create_stack_guard_pages(char* addr, size_t bytes);
344 static bool pd_create_stack_guard_pages(char* addr, size_t bytes);
345 static bool remove_stack_guard_pages(char* addr, size_t bytes);
346
347 // Map the given address to the file descriptor.
348 static char* map_memory_to_file(char* base, size_t size, int fd);
349
350 // Helper function to create a new file with template jvmheap.XXXXXX
351 static int create_file_for_heap(const char* dir, size_t size);
352
353 static char* map_memory(int fd, const char* file_name, size_t file_offset,
354 char *addr, size_t bytes, bool read_only = false,
355 bool allow_exec = false);
356 static char* remap_memory(int fd, const char* file_name, size_t file_offset,
357 char *addr, size_t bytes, bool read_only,
358 bool allow_exec);
359 static bool unmap_memory(char *addr, size_t bytes);
360 static void free_memory(char *addr, size_t bytes, size_t alignment_hint);
361 static void realign_memory(char *addr, size_t bytes, size_t alignment_hint);
362
363 // NUMA-specific interface
364 static bool numa_has_static_binding();
365 static bool numa_has_group_homing();
366 static void numa_make_local(char *addr, size_t bytes, int lgrp_hint);
367 static void numa_make_global(char *addr, size_t bytes);
368 static size_t numa_get_groups_num();
369 static size_t numa_get_leaf_groups(int *ids, size_t size);
370 static bool numa_topology_changed();
371 static int numa_get_group_id();
372
373 // Page manipulation
374 struct page_info {
375 size_t size;
376 int lgrp_id;
377 };
378 static bool get_page_info(char *start, page_info* info);
379 static char* scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found);
380
381 static char* non_memory_address_word();
382 // reserve, commit and pin the entire memory region
383 static char* reserve_memory_special(size_t size, size_t alignment,
384 char* addr, bool executable);
385 static bool release_memory_special(char* addr, size_t bytes);
386 static void large_page_init();
387 static size_t large_page_size();
388 static bool can_commit_large_page_memory();
389 static bool can_execute_large_page_memory();
390
391 // OS interface to polling page
392 static address get_polling_page() { return _polling_page; }
393 static void set_polling_page(address page) { _polling_page = page; }
394 static bool is_poll_address(address addr) { return addr >= _polling_page && addr < (_polling_page + os::vm_page_size()); }
395 static void make_polling_page_unreadable();
396 static void make_polling_page_readable();
397
398 // Routines used to serialize the thread state without using membars
399 static void serialize_thread_states();
400
401 // Since we write to the serialize page from every thread, we
402 // want stores to be on unique cache lines whenever possible
403 // in order to minimize CPU cross talk. We pre-compute the
404 // amount to shift the thread* to make this offset unique to
405 // each thread.
406 static int get_serialize_page_shift_count() {
407 return SerializePageShiftCount;
408 }
409
410 static void set_serialize_page_mask(uintptr_t mask) {
411 _serialize_page_mask = mask;
412 }
413
414 static unsigned int get_serialize_page_mask() {
415 return _serialize_page_mask;
416 }
417
418 static void set_memory_serialize_page(address page);
419
420 static address get_memory_serialize_page() {
421 return (address)_mem_serialize_page;
422 }
423
424 static inline void write_memory_serialize_page(JavaThread *thread) {
425 uintptr_t page_offset = ((uintptr_t)thread >>
426 get_serialize_page_shift_count()) &
427 get_serialize_page_mask();
428 *(volatile int32_t *)((uintptr_t)_mem_serialize_page+page_offset) = 1;
429 }
430
431 static bool is_memory_serialize_page(JavaThread *thread, address addr) {
432 if (UseMembar) return false;
433 // Previously this function calculated the exact address of this
434 // thread's serialize page, and checked if the faulting address
435 // was equal. However, some platforms mask off faulting addresses
436 // to the page size, so now we just check that the address is
437 // within the page. This makes the thread argument unnecessary,
438 // but we retain the NULL check to preserve existing behavior.
439 if (thread == NULL) return false;
440 address page = (address) _mem_serialize_page;
441 return addr >= page && addr < (page + os::vm_page_size());
442 }
443
444 static void block_on_serialize_page_trap();
445
446 // threads
447
448 enum ThreadType {
449 vm_thread,
450 cgc_thread, // Concurrent GC thread
451 pgc_thread, // Parallel GC thread
452 java_thread,
453 compiler_thread,
454 watcher_thread,
455 os_thread
456 };
457
458 static bool create_thread(Thread* thread,
459 ThreadType thr_type,
460 size_t stack_size = 0);
461 static bool create_main_thread(JavaThread* thread);
462 static bool create_attached_thread(JavaThread* thread);
463 static void pd_start_thread(Thread* thread);
464 static void start_thread(Thread* thread);
465
466 static void initialize_thread(Thread* thr);
467 static void free_thread(OSThread* osthread);
468
469 // thread id on Linux/64bit is 64bit, on Windows and Solaris, it's 32bit
470 static intx current_thread_id();
471 static int current_process_id();
472 static int sleep(Thread* thread, jlong ms, bool interruptable);
473 // Short standalone OS sleep suitable for slow path spin loop.
474 // Ignores Thread.interrupt() (so keep it short).
475 // ms = 0, will sleep for the least amount of time allowed by the OS.
476 static void naked_short_sleep(jlong ms);
477 static void infinite_sleep(); // never returns, use with CAUTION
478 static void naked_yield () ;
479 static OSReturn set_priority(Thread* thread, ThreadPriority priority);
480 static OSReturn get_priority(const Thread* const thread, ThreadPriority& priority);
481
482 static void interrupt(Thread* thread);
483 static bool is_interrupted(Thread* thread, bool clear_interrupted);
484
485 static int pd_self_suspend_thread(Thread* thread);
486
487 static ExtendedPC fetch_frame_from_context(const void* ucVoid, intptr_t** sp, intptr_t** fp);
488 static frame fetch_frame_from_context(const void* ucVoid);
489 static frame fetch_frame_from_ucontext(Thread* thread, void* ucVoid);
490
491 static ExtendedPC get_thread_pc(Thread *thread);
492 static void breakpoint();
493 static bool start_debugging(char *buf, int buflen);
494
495 static address current_stack_pointer();
496 static address current_stack_base();
497 static size_t current_stack_size();
498
499 static void verify_stack_alignment() PRODUCT_RETURN;
500
501 static bool message_box(const char* title, const char* message);
502 static char* do_you_want_to_debug(const char* message);
503
504 // run cmd in a separate process and return its exit code; or -1 on failures
505 static int fork_and_exec(char *cmd);
506
507 // Call ::exit() on all platforms but Windows
508 static void exit(int num);
509
510 // Terminate the VM, but don't exit the process
511 static void shutdown();
512
513 // Terminate with an error. Default is to generate a core file on platforms
514 // that support such things. This calls shutdown() and then aborts.
515 static void abort(bool dump_core, void *siginfo, const void *context);
516 static void abort(bool dump_core = true);
517
518 // Die immediately, no exit hook, no abort hook, no cleanup.
519 static void die();
520
521 // File i/o operations
522 static const int default_file_open_flags();
523 static int open(const char *path, int oflag, int mode);
524 static FILE* open(int fd, const char* mode);
525 static int close(int fd);
526 static jlong lseek(int fd, jlong offset, int whence);
527 static char* native_path(char *path);
528 static int ftruncate(int fd, jlong length);
529 static int fsync(int fd);
530 static int available(int fd, jlong *bytes);
531 static int get_fileno(FILE* fp);
532 static void flockfile(FILE* fp);
533 static void funlockfile(FILE* fp);
534
535 static int compare_file_modified_times(const char* file1, const char* file2);
536
537 //File i/o operations
538
539 static size_t read(int fd, void *buf, unsigned int nBytes);
540 static size_t read_at(int fd, void *buf, unsigned int nBytes, jlong offset);
541 static size_t restartable_read(int fd, void *buf, unsigned int nBytes);
542 static size_t write(int fd, const void *buf, unsigned int nBytes);
543
544 // Reading directories.
545 static DIR* opendir(const char* dirname);
546 static int readdir_buf_size(const char *path);
547 static struct dirent* readdir(DIR* dirp, dirent* dbuf);
548 static int closedir(DIR* dirp);
549
550 // Dynamic library extension
551 static const char* dll_file_extension();
552
553 static const char* get_temp_directory();
554 static const char* get_current_directory(char *buf, size_t buflen);
555
556 // Builds a platform-specific full library path given a ld path and lib name
557 // Returns true if buffer contains full path to existing file, false otherwise
558 static bool dll_build_name(char* buffer, size_t size,
559 const char* pathname, const char* fname);
560
561 // Symbol lookup, find nearest function name; basically it implements
562 // dladdr() for all platforms. Name of the nearest function is copied
563 // to buf. Distance from its base address is optionally returned as offset.
564 // If function name is not found, buf[0] is set to '\0' and offset is
565 // set to -1 (if offset is non-NULL).
566 static bool dll_address_to_function_name(address addr, char* buf,
567 int buflen, int* offset,
568 bool demangle = true);
569
570 // Locate DLL/DSO. On success, full path of the library is copied to
571 // buf, and offset is optionally set to be the distance between addr
572 // and the library's base address. On failure, buf[0] is set to '\0'
573 // and offset is set to -1 (if offset is non-NULL).
574 static bool dll_address_to_library_name(address addr, char* buf,
575 int buflen, int* offset);
576
577 // Find out whether the pc is in the static code for jvm.dll/libjvm.so.
578 static bool address_is_in_vm(address addr);
579
580 // Loads .dll/.so and
581 // in case of error it checks if .dll/.so was built for the
582 // same architecture as HotSpot is running on
583 static void* dll_load(const char *name, char *ebuf, int ebuflen);
584
585 // lookup symbol in a shared library
586 static void* dll_lookup(void* handle, const char* name);
587
588 // Unload library
589 static void dll_unload(void *lib);
590
591 // Callback for loaded module information
592 // Input parameters:
593 // char* module_file_name,
594 // address module_base_addr,
595 // address module_top_addr,
596 // void* param
597 typedef int (*LoadedModulesCallbackFunc)(const char *, address, address, void *);
598
599 static int get_loaded_modules_info(LoadedModulesCallbackFunc callback, void *param);
600
601 // Return the handle of this process
602 static void* get_default_process_handle();
603
604 // Check for static linked agent library
605 static bool find_builtin_agent(AgentLibrary *agent_lib, const char *syms[],
606 size_t syms_len);
607
608 // Find agent entry point
609 static void *find_agent_function(AgentLibrary *agent_lib, bool check_lib,
610 const char *syms[], size_t syms_len);
611
612 // Write to stream
613 static int log_vsnprintf(char* buf, size_t len, const char* fmt, va_list args) ATTRIBUTE_PRINTF(3, 0);
614
615 // Get host name in buffer provided
616 static bool get_host_name(char* buf, size_t buflen);
617
618 // Print out system information; they are called by fatal error handler.
619 // Output format may be different on different platforms.
620 static void print_os_info(outputStream* st);
621 static void print_os_info_brief(outputStream* st);
622 static void print_cpu_info(outputStream* st, char* buf, size_t buflen);
623 static void pd_print_cpu_info(outputStream* st, char* buf, size_t buflen);
624 static void print_summary_info(outputStream* st, char* buf, size_t buflen);
625 static void print_memory_info(outputStream* st);
626 static void print_dll_info(outputStream* st);
627 static void print_environment_variables(outputStream* st, const char** env_list);
628 static void print_context(outputStream* st, const void* context);
629 static void print_register_info(outputStream* st, const void* context);
630 static void print_siginfo(outputStream* st, const void* siginfo);
631 static void print_signal_handlers(outputStream* st, char* buf, size_t buflen);
632 static void print_date_and_time(outputStream* st, char* buf, size_t buflen);
633
634 static void print_location(outputStream* st, intptr_t x, bool verbose = false);
635 static size_t lasterror(char *buf, size_t len);
636 static int get_last_error();
637
638 // Replacement for strerror().
639 // Will return the english description of the error (e.g. "File not found", as
640 // suggested in the POSIX standard.
641 // Will return "Unknown error" for an unknown errno value.
642 // Will not attempt to localize the returned string.
643 // Will always return a valid string which is a static constant.
644 // Will not change the value of errno.
645 static const char* strerror(int e);
646
647 // Will return the literalized version of the given errno (e.g. "EINVAL"
648 // for EINVAL).
649 // Will return "Unknown error" for an unknown errno value.
650 // Will always return a valid string which is a static constant.
651 // Will not change the value of errno.
652 static const char* errno_name(int e);
653
654 // Determines whether the calling process is being debugged by a user-mode debugger.
655 static bool is_debugger_attached();
656
657 // wait for a key press if PauseAtExit is set
658 static void wait_for_keypress_at_exit(void);
659
660 // The following two functions are used by fatal error handler to trace
661 // native (C) frames. They are not part of frame.hpp/frame.cpp because
662 // frame.hpp/cpp assume thread is JavaThread, and also because different
663 // OS/compiler may have different convention or provide different API to
664 // walk C frames.
665 //
666 // We don't attempt to become a debugger, so we only follow frames if that
667 // does not require a lookup in the unwind table, which is part of the binary
668 // file but may be unsafe to read after a fatal error. So on x86, we can
669 // only walk stack if %ebp is used as frame pointer; on ia64, it's not
670 // possible to walk C stack without having the unwind table.
671 static bool is_first_C_frame(frame *fr);
672 static frame get_sender_for_C_frame(frame *fr);
673
674 // return current frame. pc() and sp() are set to NULL on failure.
675 static frame current_frame();
676
677 static void print_hex_dump(outputStream* st, address start, address end, int unitsize);
678
679 // returns a string to describe the exception/signal;
680 // returns NULL if exception_code is not an OS exception/signal.
681 static const char* exception_name(int exception_code, char* buf, size_t buflen);
682
683 // Returns the signal number (e.g. 11) for a given signal name (SIGSEGV).
684 static int get_signal_number(const char* signal_name);
685
686 // Returns native Java library, loads if necessary
687 static void* native_java_library();
688
689 // Fills in path to jvm.dll/libjvm.so (used by the Disassembler)
690 static void jvm_path(char *buf, jint buflen);
691
692 // Returns true if we are running in a headless jre.
693 static bool is_headless_jre();
694
695 // JNI names
696 static void print_jni_name_prefix_on(outputStream* st, int args_size);
697 static void print_jni_name_suffix_on(outputStream* st, int args_size);
698
699 // Init os specific system properties values
700 static void init_system_properties_values();
701
702 // IO operations, non-JVM_ version.
703 static int stat(const char* path, struct stat* sbuf);
704 static bool dir_is_empty(const char* path);
705
706 // IO operations on binary files
707 static int create_binary_file(const char* path, bool rewrite_existing);
708 static jlong current_file_offset(int fd);
709 static jlong seek_to_file_offset(int fd, jlong offset);
710
711 // Retrieve native stack frames.
712 // Parameter:
713 // stack: an array to storage stack pointers.
714 // frames: size of above array.
715 // toSkip: number of stack frames to skip at the beginning.
716 // Return: number of stack frames captured.
717 static int get_native_stack(address* stack, int size, int toSkip = 0);
718
719 // General allocation (must be MT-safe)
720 static void* malloc (size_t size, MEMFLAGS flags, const NativeCallStack& stack);
721 static void* malloc (size_t size, MEMFLAGS flags);
722 static void* realloc (void *memblock, size_t size, MEMFLAGS flag, const NativeCallStack& stack);
723 static void* realloc (void *memblock, size_t size, MEMFLAGS flag);
724
725 static void free (void *memblock);
726 static bool check_heap(bool force = false); // verify C heap integrity
727 static char* strdup(const char *, MEMFLAGS flags = mtInternal); // Like strdup
728 // Like strdup, but exit VM when strdup() returns NULL
729 static char* strdup_check_oom(const char*, MEMFLAGS flags = mtInternal);
730
731 #ifndef PRODUCT
732 static julong num_mallocs; // # of calls to malloc/realloc
733 static julong alloc_bytes; // # of bytes allocated
734 static julong num_frees; // # of calls to free
735 static julong free_bytes; // # of bytes freed
736 #endif
737
738 // SocketInterface (ex HPI SocketInterface )
739 static int socket(int domain, int type, int protocol);
740 static int socket_close(int fd);
741 static int recv(int fd, char* buf, size_t nBytes, uint flags);
742 static int send(int fd, char* buf, size_t nBytes, uint flags);
743 static int raw_send(int fd, char* buf, size_t nBytes, uint flags);
744 static int connect(int fd, struct sockaddr* him, socklen_t len);
745 static struct hostent* get_host_by_name(char* name);
746
747 // Support for signals (see JVM_RaiseSignal, JVM_RegisterSignal)
748 static void signal_init();
749 static void signal_init_pd();
750 static void signal_notify(int signal_number);
751 static void* signal(int signal_number, void* handler);
752 static void signal_raise(int signal_number);
753 static int signal_wait();
754 static int signal_lookup();
755 static void* user_handler();
756 static void terminate_signal_thread();
757 static int sigexitnum_pd();
758
759 // random number generation
760 static long random(); // return 32bit pseudorandom number
761 static void init_random(long initval); // initialize random sequence
762
763 // Structured OS Exception support
764 static void os_exception_wrapper(java_call_t f, JavaValue* value, const methodHandle& method, JavaCallArguments* args, Thread* thread);
765
766 // On Posix compatible OS it will simply check core dump limits while on Windows
767 // it will check if dump file can be created. Check or prepare a core dump to be
768 // taken at a later point in the same thread in os::abort(). Use the caller
769 // provided buffer as a scratch buffer. The status message which will be written
770 // into the error log either is file location or a short error message, depending
771 // on the checking result.
772 static void check_dump_limit(char* buffer, size_t bufferSize);
773
774 // Get the default path to the core file
775 // Returns the length of the string
776 static int get_core_path(char* buffer, size_t bufferSize);
777
778 // JVMTI & JVM monitoring and management support
779 // The thread_cpu_time() and current_thread_cpu_time() are only
780 // supported if is_thread_cpu_time_supported() returns true.
781 // They are not supported on Solaris T1.
782
783 // Thread CPU Time - return the fast estimate on a platform
784 // On Solaris - call gethrvtime (fast) - user time only
785 // On Linux - fast clock_gettime where available - user+sys
786 // - otherwise: very slow /proc fs - user+sys
787 // On Windows - GetThreadTimes - user+sys
788 static jlong current_thread_cpu_time();
789 static jlong thread_cpu_time(Thread* t);
790
791 // Thread CPU Time with user_sys_cpu_time parameter.
792 //
793 // If user_sys_cpu_time is true, user+sys time is returned.
794 // Otherwise, only user time is returned
795 static jlong current_thread_cpu_time(bool user_sys_cpu_time);
796 static jlong thread_cpu_time(Thread* t, bool user_sys_cpu_time);
797
798 // Return a bunch of info about the timers.
799 // Note that the returned info for these two functions may be different
800 // on some platforms
801 static void current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr);
802 static void thread_cpu_time_info(jvmtiTimerInfo *info_ptr);
803
804 static bool is_thread_cpu_time_supported();
805
806 // System loadavg support. Returns -1 if load average cannot be obtained.
807 static int loadavg(double loadavg[], int nelem);
808
809 // Hook for os specific jvm options that we don't want to abort on seeing
810 static bool obsolete_option(const JavaVMOption *option);
811
812 // Amount beyond the callee frame size that we bang the stack.
813 static int extra_bang_size_in_bytes();
814
815 static char** split_path(const char* path, int* n);
816
817 // Extensions
818 #include "runtime/os_ext.hpp"
819
820 public:
821 class CrashProtectionCallback : public StackObj {
822 public:
823 virtual void call() = 0;
824 };
825
826 // Platform dependent stuff
827 #ifdef TARGET_OS_FAMILY_linux
828 # include "os_linux.hpp"
829 # include "os_posix.hpp"
830 #endif
831 #ifdef TARGET_OS_FAMILY_solaris
832 # include "os_solaris.hpp"
833 # include "os_posix.hpp"
834 #endif
835 #ifdef TARGET_OS_FAMILY_windows
836 # include "os_windows.hpp"
837 #endif
838 #ifdef TARGET_OS_FAMILY_aix
839 # include "os_aix.hpp"
840 # include "os_posix.hpp"
841 #endif
842 #ifdef TARGET_OS_FAMILY_bsd
843 # include "os_posix.hpp"
844 # include "os_bsd.hpp"
845 #endif
846 #ifdef TARGET_OS_ARCH_linux_x86
847 # include "os_linux_x86.hpp"
848 #endif
849 #ifdef TARGET_OS_ARCH_linux_sparc
850 # include "os_linux_sparc.hpp"
851 #endif
852 #ifdef TARGET_OS_ARCH_linux_zero
853 # include "os_linux_zero.hpp"
854 #endif
855 #ifdef TARGET_OS_ARCH_solaris_x86
856 # include "os_solaris_x86.hpp"
857 #endif
858 #ifdef TARGET_OS_ARCH_solaris_sparc
859 # include "os_solaris_sparc.hpp"
860 #endif
861 #ifdef TARGET_OS_ARCH_windows_x86
862 # include "os_windows_x86.hpp"
863 #endif
864 #ifdef TARGET_OS_ARCH_linux_arm
865 # include "os_linux_arm.hpp"
866 #endif
867 #ifdef TARGET_OS_ARCH_linux_ppc
868 # include "os_linux_ppc.hpp"
869 #endif
870 #ifdef TARGET_OS_ARCH_aix_ppc
871 # include "os_aix_ppc.hpp"
872 #endif
873 #ifdef TARGET_OS_ARCH_linux_aarch64
874 # include "os_linux_aarch64.hpp"
875 #endif
876 #ifdef TARGET_OS_ARCH_bsd_x86
877 # include "os_bsd_x86.hpp"
878 #endif
879 #ifdef TARGET_OS_ARCH_bsd_zero
880 # include "os_bsd_zero.hpp"
881 #endif
882
883 #ifndef OS_NATIVE_THREAD_CREATION_FAILED_MSG
884 #define OS_NATIVE_THREAD_CREATION_FAILED_MSG "unable to create native thread: possibly out of memory or process/resource limits reached"
885 #endif
886
887 public:
888 #ifndef PLATFORM_PRINT_NATIVE_STACK
889 // No platform-specific code for printing the native stack.
890 static bool platform_print_native_stack(outputStream* st, const void* context,
891 char *buf, int buf_size) {
892 return false;
893 }
894 #endif
895
896 // debugging support (mostly used by debug.cpp but also fatal error handler)
897 static bool find(address pc, outputStream* st = tty); // OS specific function to make sense out of an address
898
899 static bool dont_yield(); // when true, JVM_Yield() is nop
900 static void print_statistics();
901
902 // Thread priority helpers (implemented in OS-specific part)
903 static OSReturn set_native_priority(Thread* thread, int native_prio);
904 static OSReturn get_native_priority(const Thread* const thread, int* priority_ptr);
905 static int java_to_os_priority[CriticalPriority + 1];
906 // Hint to the underlying OS that a task switch would not be good.
907 // Void return because it's a hint and can fail.
908 static void hint_no_preempt();
909 static const char* native_thread_creation_failed_msg() {
910 return OS_NATIVE_THREAD_CREATION_FAILED_MSG;
911 }
912
913 // Used at creation if requested by the diagnostic flag PauseAtStartup.
914 // Causes the VM to wait until an external stimulus has been applied
915 // (for Unix, that stimulus is a signal, for Windows, an external
916 // ResumeThread call)
917 static void pause();
918
919 // Builds a platform dependent Agent_OnLoad_<libname> function name
920 // which is used to find statically linked in agents.
921 static char* build_agent_function_name(const char *sym, const char *cname,
922 bool is_absolute_path);
923
924 class SuspendedThreadTaskContext {
925 public:
926 SuspendedThreadTaskContext(Thread* thread, void *ucontext) : _thread(thread), _ucontext(ucontext) {}
927 Thread* thread() const { return _thread; }
928 void* ucontext() const { return _ucontext; }
929 private:
930 Thread* _thread;
931 void* _ucontext;
932 };
933
934 class SuspendedThreadTask {
935 public:
936 SuspendedThreadTask(Thread* thread) : _thread(thread), _done(false) {}
937 virtual ~SuspendedThreadTask() {}
938 void run();
939 bool is_done() { return _done; }
940 virtual void do_task(const SuspendedThreadTaskContext& context) = 0;
941 protected:
942 private:
943 void internal_do_task();
944 Thread* _thread;
945 bool _done;
946 };
947
948 #ifndef TARGET_OS_FAMILY_windows
949 // Suspend/resume support
950 // Protocol:
951 //
952 // a thread starts in SR_RUNNING
953 //
954 // SR_RUNNING can go to
955 // * SR_SUSPEND_REQUEST when the WatcherThread wants to suspend it
956 // SR_SUSPEND_REQUEST can go to
957 // * SR_RUNNING if WatcherThread decides it waited for SR_SUSPENDED too long (timeout)
958 // * SR_SUSPENDED if the stopped thread receives the signal and switches state
959 // SR_SUSPENDED can go to
960 // * SR_WAKEUP_REQUEST when the WatcherThread has done the work and wants to resume
961 // SR_WAKEUP_REQUEST can go to
962 // * SR_RUNNING when the stopped thread receives the signal
963 // * SR_WAKEUP_REQUEST on timeout (resend the signal and try again)
964 class SuspendResume {
965 public:
966 enum State {
967 SR_RUNNING,
968 SR_SUSPEND_REQUEST,
969 SR_SUSPENDED,
970 SR_WAKEUP_REQUEST
971 };
972
973 private:
974 volatile State _state;
975
976 private:
977 /* try to switch state from state "from" to state "to"
978 * returns the state set after the method is complete
979 */
980 State switch_state(State from, State to);
981
982 public:
983 SuspendResume() : _state(SR_RUNNING) { }
984
985 State state() const { return _state; }
986
987 State request_suspend() {
988 return switch_state(SR_RUNNING, SR_SUSPEND_REQUEST);
989 }
990
991 State cancel_suspend() {
992 return switch_state(SR_SUSPEND_REQUEST, SR_RUNNING);
993 }
994
995 State suspended() {
996 return switch_state(SR_SUSPEND_REQUEST, SR_SUSPENDED);
997 }
998
999 State request_wakeup() {
1000 return switch_state(SR_SUSPENDED, SR_WAKEUP_REQUEST);
1001 }
1002
1003 State running() {
1004 return switch_state(SR_WAKEUP_REQUEST, SR_RUNNING);
1005 }
1006
1007 bool is_running() const {
1008 return _state == SR_RUNNING;
1009 }
1010
1011 bool is_suspend_request() const {
1012 return _state == SR_SUSPEND_REQUEST;
1013 }
1014
1015 bool is_suspended() const {
1016 return _state == SR_SUSPENDED;
1017 }
1018 };
1019 #endif
1020
1021
1022 protected:
1023 static long _rand_seed; // seed for random number generator
1024 static int _processor_count; // number of processors
1025
1026 static char* format_boot_path(const char* format_string,
1027 const char* home,
1028 int home_len,
1029 char fileSep,
1030 char pathSep);
1031 static bool set_boot_path(char fileSep, char pathSep);
1032
1033 };
1034
1035 // Note that "PAUSE" is almost always used with synchronization
1036 // so arguably we should provide Atomic::SpinPause() instead
1037 // of the global SpinPause() with C linkage.
1038 // It'd also be eligible for inlining on many platforms.
1039
1040 extern "C" int SpinPause();
1041
1042 #endif // SHARE_VM_RUNTIME_OS_HPP