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