1 /*
2 * Copyright (c) 1997, 2018, 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/atomic.hpp"
30 #include "runtime/extendedPC.hpp"
31 #include "runtime/handles.hpp"
32 #include "utilities/top.hpp"
33 #ifdef TARGET_OS_FAMILY_linux
34 # include "jvm_linux.h"
35 # include <setjmp.h>
36 #endif
37 #ifdef TARGET_OS_FAMILY_solaris
38 # include "jvm_solaris.h"
39 # include <setjmp.h>
40 #endif
41 #ifdef TARGET_OS_FAMILY_windows
42 # include "jvm_windows.h"
43 #endif
44 #ifdef TARGET_OS_FAMILY_aix
45 # include "jvm_aix.h"
46 # include <setjmp.h>
47 #endif
48 #ifdef TARGET_OS_FAMILY_bsd
49 # include "jvm_bsd.h"
50 # include <setjmp.h>
51 # ifdef __APPLE__
52 # include <mach/mach_time.h>
53 # endif
54 #endif
55
56 class AgentLibrary;
57
58 // os defines the interface to operating system; this includes traditional
59 // OS services (time, I/O) as well as other functionality with system-
60 // dependent code.
61
62 typedef void (*dll_func)(...);
63
64 class Thread;
65 class JavaThread;
66 class Event;
67 class DLL;
68 class FileHandle;
69 class NativeCallStack;
70
71 template<class E> class GrowableArray;
72
73 // %%%%% Moved ThreadState, START_FN, OSThread to new osThread.hpp. -- Rose
74
75 // Platform-independent error return values from OS functions
76 enum OSReturn {
77 OS_OK = 0, // Operation was successful
78 OS_ERR = -1, // Operation failed
79 OS_INTRPT = -2, // Operation was interrupted
80 OS_TIMEOUT = -3, // Operation timed out
81 OS_NOMEM = -5, // Operation failed for lack of memory
82 OS_NORESOURCE = -6 // Operation failed for lack of nonmemory resource
83 };
84
85 enum ThreadPriority { // JLS 20.20.1-3
86 NoPriority = -1, // Initial non-priority value
87 MinPriority = 1, // Minimum priority
88 NormPriority = 5, // Normal (non-daemon) priority
89 NearMaxPriority = 9, // High priority, used for VMThread
90 MaxPriority = 10, // Highest priority, used for WatcherThread
91 // ensures that VMThread doesn't starve profiler
92 CriticalPriority = 11 // Critical thread priority
93 };
94
95 // Executable parameter flag for os::commit_memory() and
96 // os::commit_memory_or_exit().
97 const bool ExecMem = true;
98
99 // Typedef for structured exception handling support
100 typedef void (*java_call_t)(JavaValue* value, methodHandle* method, JavaCallArguments* args, Thread* thread);
101
102 class MallocTracker;
103
104 class os: AllStatic {
105 friend class VMStructs;
106 friend class MallocTracker;
107 public:
108 enum { page_sizes_max = 9 }; // Size of _page_sizes array (8 plus a sentinel)
109
110 private:
111 static OSThread* _starting_thread;
112 static address _polling_page;
113 static volatile int32_t * _mem_serialize_page;
114 static uintptr_t _serialize_page_mask;
115 public:
116 static size_t _page_sizes[page_sizes_max];
117
118 private:
119 static void init_page_sizes(size_t default_page_size) {
120 _page_sizes[0] = default_page_size;
121 _page_sizes[1] = 0; // sentinel
122 }
123
124 static char* pd_reserve_memory(size_t bytes, char* addr = 0,
125 size_t alignment_hint = 0);
126 static char* pd_attempt_reserve_memory_at(size_t bytes, char* addr);
127 static void pd_split_reserved_memory(char *base, size_t size,
128 size_t split, bool realloc);
129 static bool pd_commit_memory(char* addr, size_t bytes, bool executable);
130 static bool pd_commit_memory(char* addr, size_t size, size_t alignment_hint,
131 bool executable);
132 // Same as pd_commit_memory() that either succeeds or calls
133 // vm_exit_out_of_memory() with the specified mesg.
134 static void pd_commit_memory_or_exit(char* addr, size_t bytes,
135 bool executable, const char* mesg);
136 static void pd_commit_memory_or_exit(char* addr, size_t size,
137 size_t alignment_hint,
138 bool executable, const char* mesg);
139 static bool pd_uncommit_memory(char* addr, size_t bytes);
140 static bool pd_release_memory(char* addr, size_t bytes);
141
142 static char* pd_map_memory(int fd, const char* file_name, size_t file_offset,
143 char *addr, size_t bytes, bool read_only = false,
144 bool allow_exec = false);
145 static char* pd_remap_memory(int fd, const char* file_name, size_t file_offset,
146 char *addr, size_t bytes, bool read_only,
147 bool allow_exec);
148 static bool pd_unmap_memory(char *addr, size_t bytes);
149 static void pd_free_memory(char *addr, size_t bytes, size_t alignment_hint);
150 static void pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint);
151
152 static size_t page_size_for_region(size_t region_size, size_t min_pages, bool must_be_aligned);
153
154 static void initialize_initial_active_processor_count();
155 public:
156 static void init(void); // Called before command line parsing
157 static void init_before_ergo(void); // Called after command line parsing
158 // before VM ergonomics processing.
159 static jint init_2(void); // Called after command line parsing
160 // and VM ergonomics processing
161 static void init_globals(void) { // Called from init_globals() in init.cpp
162 init_globals_ext();
163 }
164
165 // File names are case-insensitive on windows only
166 // Override me as needed
167 static int file_name_strcmp(const char* s1, const char* s2);
168
169 // get/unset environment variable
170 static bool getenv(const char* name, char* buffer, int len);
171 static bool unsetenv(const char* name);
172
173 static bool have_special_privileges();
174
175 static jlong javaTimeMillis();
176 static jlong javaTimeNanos();
177 static void javaTimeNanos_info(jvmtiTimerInfo *info_ptr);
178 static void run_periodic_checks();
179
180
181 // Returns the elapsed time in seconds since the vm started.
182 static double elapsedTime();
183
184 // Returns real time in seconds since an arbitrary point
185 // in the past.
186 static bool getTimesSecs(double* process_real_time,
187 double* process_user_time,
188 double* process_system_time);
189
190 // Interface to the performance counter
191 static jlong elapsed_counter();
192 static jlong elapsed_frequency();
193
194 // The "virtual time" of a thread is the amount of time a thread has
195 // actually run. The first function indicates whether the OS supports
196 // this functionality for the current thread, and if so:
197 // * the second enables vtime tracking (if that is required).
198 // * the third tells whether vtime is enabled.
199 // * the fourth returns the elapsed virtual time for the current
200 // thread.
201 static bool supports_vtime();
202 static bool enable_vtime();
203 static bool vtime_enabled();
204 static double elapsedVTime();
205
206 // Return current local time in a string (YYYY-MM-DD HH:MM:SS).
207 // It is MT safe, but not async-safe, as reading time zone
208 // information may require a lock on some platforms.
209 static char* local_time_string(char *buf, size_t buflen);
210 static struct tm* localtime_pd (const time_t* clock, struct tm* res);
211 // Fill in buffer with current local time as an ISO-8601 string.
212 // E.g., YYYY-MM-DDThh:mm:ss.mmm+zzzz.
213 // Returns buffer, or NULL if it failed.
214 static char* iso8601_time(char* buffer, size_t buffer_length);
215
216 // Interface for detecting multiprocessor system
217 static inline bool is_MP() {
218 // During bootstrap if _processor_count is not yet initialized
219 // we claim to be MP as that is safest. If any platform has a
220 // stub generator that might be triggered in this phase and for
221 // which being declared MP when in fact not, is a problem - then
222 // the bootstrap routine for the stub generator needs to check
223 // the processor count directly and leave the bootstrap routine
224 // in place until called after initialization has ocurred.
225 return (_processor_count != 1) || AssumeMP;
226 }
227 static julong available_memory();
228 static julong physical_memory();
229 static bool has_allocatable_memory_limit(julong* limit);
230 static bool is_server_class_machine();
231
232 // number of CPUs
233 static int processor_count() {
234 return _processor_count;
235 }
236 static void set_processor_count(int count) { _processor_count = count; }
237
238 // Returns the number of CPUs this process is currently allowed to run on.
239 // Note that on some OSes this can change dynamically.
240 static int active_processor_count();
241
242 // At startup the number of active CPUs this process is allowed to run on.
243 // This value does not change dynamically. May be different from active_processor_count().
244 static int initial_active_processor_count() {
245 assert(_initial_active_processor_count > 0, "Initial active processor count not set yet.");
246 return _initial_active_processor_count;
247 }
248
249 // Bind processes to processors.
250 // This is a two step procedure:
251 // first you generate a distribution of processes to processors,
252 // then you bind processes according to that distribution.
253 // Compute a distribution for number of processes to processors.
254 // Stores the processor id's into the distribution array argument.
255 // Returns true if it worked, false if it didn't.
256 static bool distribute_processes(uint length, uint* distribution);
257 // Binds the current process to a processor.
258 // Returns true if it worked, false if it didn't.
259 static bool bind_to_processor(uint processor_id);
260
261 // Give a name to the current thread.
262 static void set_native_thread_name(const char *name);
263
264 // Interface for stack banging (predetect possible stack overflow for
265 // exception processing) There are guard pages, and above that shadow
266 // pages for stack overflow checking.
267 static bool uses_stack_guard_pages();
268 static bool allocate_stack_guard_pages();
269 static void bang_stack_shadow_pages();
270 static bool stack_shadow_pages_available(Thread *thread, methodHandle method);
271
272 // OS interface to Virtual Memory
273
274 // Return the default page size.
275 static int vm_page_size();
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 will divide region_size.
280 static size_t page_size_for_region_aligned(size_t region_size, size_t min_pages);
281
282 // Returns the page size to use for a region of memory.
283 // region_size / min_pages will always be greater than or equal to the
284 // returned value. The returned value might not divide region_size.
285 static size_t page_size_for_region_unaligned(size_t region_size, size_t min_pages);
286
287 // Return the largest page size that can be used
288 static size_t max_page_size() {
289 // The _page_sizes array is sorted in descending order.
290 return _page_sizes[0];
291 }
292
293 // Methods for tracing page sizes returned by the above method; enabled by
294 // TracePageSizes. The region_{min,max}_size parameters should be the values
295 // passed to page_size_for_region() and page_size should be the result of that
296 // call. The (optional) base and size parameters should come from the
297 // ReservedSpace base() and size() methods.
298 static void trace_page_sizes(const char* str, const size_t* page_sizes,
299 int count) PRODUCT_RETURN;
300 static void trace_page_sizes(const char* str, const size_t region_min_size,
301 const size_t region_max_size,
302 const size_t page_size,
303 const char* base = NULL,
304 const size_t size = 0) PRODUCT_RETURN;
305
306 static int vm_allocation_granularity();
307 static char* reserve_memory(size_t bytes, char* addr = 0,
308 size_t alignment_hint = 0);
309 static char* reserve_memory(size_t bytes, char* addr,
310 size_t alignment_hint, MEMFLAGS flags);
311 static char* reserve_memory_aligned(size_t size, size_t alignment);
312 static char* attempt_reserve_memory_at(size_t bytes, char* addr);
313 static void split_reserved_memory(char *base, size_t size,
314 size_t split, bool realloc);
315 static bool commit_memory(char* addr, size_t bytes, bool executable);
316 static bool commit_memory(char* addr, size_t size, size_t alignment_hint,
317 bool executable);
318 // Same as commit_memory() that either succeeds or calls
319 // vm_exit_out_of_memory() with the specified mesg.
320 static void commit_memory_or_exit(char* addr, size_t bytes,
321 bool executable, const char* mesg);
322 static void commit_memory_or_exit(char* addr, size_t size,
323 size_t alignment_hint,
324 bool executable, const char* mesg);
325 static bool uncommit_memory(char* addr, size_t bytes);
326 static bool release_memory(char* addr, size_t bytes);
327
328 // Touch memory pages that cover the memory range from start to end (exclusive)
329 // to make the OS back the memory range with actual memory.
330 // Current implementation may not touch the last page if unaligned addresses
331 // are passed.
332 static void pretouch_memory(char* start, char* end);
333
334 enum ProtType { MEM_PROT_NONE, MEM_PROT_READ, MEM_PROT_RW, MEM_PROT_RWX };
335 static bool protect_memory(char* addr, size_t bytes, ProtType prot,
336 bool is_committed = true);
337
338 static bool guard_memory(char* addr, size_t bytes);
339 static bool unguard_memory(char* addr, size_t bytes);
340 static bool create_stack_guard_pages(char* addr, size_t bytes);
341 static bool pd_create_stack_guard_pages(char* addr, size_t bytes);
342 static bool remove_stack_guard_pages(char* addr, size_t bytes);
343
344 static char* map_memory(int fd, const char* file_name, size_t file_offset,
345 char *addr, size_t bytes, bool read_only = false,
346 bool allow_exec = false);
347 static char* remap_memory(int fd, const char* file_name, size_t file_offset,
348 char *addr, size_t bytes, bool read_only,
349 bool allow_exec);
350 static bool unmap_memory(char *addr, size_t bytes);
351 static void free_memory(char *addr, size_t bytes, size_t alignment_hint);
352 static void realign_memory(char *addr, size_t bytes, size_t alignment_hint);
353
354 // NUMA-specific interface
355 static bool numa_has_static_binding();
356 static bool numa_has_group_homing();
357 static void numa_make_local(char *addr, size_t bytes, int lgrp_hint);
358 static void numa_make_global(char *addr, size_t bytes);
359 static size_t numa_get_groups_num();
360 static size_t numa_get_leaf_groups(int *ids, size_t size);
361 static bool numa_topology_changed();
362 static int numa_get_group_id();
363
364 // Page manipulation
365 struct page_info {
366 size_t size;
367 int lgrp_id;
368 };
369 static bool get_page_info(char *start, page_info* info);
370 static char* scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found);
371
372 static char* non_memory_address_word();
373 // reserve, commit and pin the entire memory region
374 static char* reserve_memory_special(size_t size, size_t alignment,
375 char* addr, bool executable);
376 static bool release_memory_special(char* addr, size_t bytes);
377 static void large_page_init();
378 static size_t large_page_size();
379 static bool can_commit_large_page_memory();
380 static bool can_execute_large_page_memory();
381
382 // OS interface to polling page
383 static address get_polling_page() { return _polling_page; }
384 static void set_polling_page(address page) { _polling_page = page; }
385 static bool is_poll_address(address addr) { return addr >= _polling_page && addr < (_polling_page + os::vm_page_size()); }
386 static void make_polling_page_unreadable();
387 static void make_polling_page_readable();
388
389 // Routines used to serialize the thread state without using membars
390 static void serialize_thread_states();
391
392 // Since we write to the serialize page from every thread, we
393 // want stores to be on unique cache lines whenever possible
394 // in order to minimize CPU cross talk. We pre-compute the
395 // amount to shift the thread* to make this offset unique to
396 // each thread.
397 static int get_serialize_page_shift_count() {
398 return SerializePageShiftCount;
399 }
400
401 static void set_serialize_page_mask(uintptr_t mask) {
402 _serialize_page_mask = mask;
403 }
404
405 static unsigned int get_serialize_page_mask() {
406 return _serialize_page_mask;
407 }
408
409 static void set_memory_serialize_page(address page);
410
411 static address get_memory_serialize_page() {
412 return (address)_mem_serialize_page;
413 }
414
415 static inline void write_memory_serialize_page(JavaThread *thread) {
416 uintptr_t page_offset = ((uintptr_t)thread >>
417 get_serialize_page_shift_count()) &
418 get_serialize_page_mask();
419 *(volatile int32_t *)((uintptr_t)_mem_serialize_page+page_offset) = 1;
420 }
421
422 static bool is_memory_serialize_page(JavaThread *thread, address addr) {
423 if (UseMembar) return false;
424 // Previously this function calculated the exact address of this
425 // thread's serialize page, and checked if the faulting address
426 // was equal. However, some platforms mask off faulting addresses
427 // to the page size, so now we just check that the address is
428 // within the page. This makes the thread argument unnecessary,
429 // but we retain the NULL check to preserve existing behaviour.
430 if (thread == NULL) return false;
431 address page = (address) _mem_serialize_page;
432 return addr >= page && addr < (page + os::vm_page_size());
433 }
434
435 static void block_on_serialize_page_trap();
436
437 // threads
438
439 enum ThreadType {
440 vm_thread,
441 cgc_thread, // Concurrent GC thread
442 pgc_thread, // Parallel GC thread
443 java_thread,
444 compiler_thread,
445 watcher_thread,
446 os_thread
447 };
448
449 static bool create_thread(Thread* thread,
450 ThreadType thr_type,
451 size_t stack_size = 0);
452
453 // The "main thread", also known as "starting thread", is the thread
454 // that loads/creates the JVM via JNI_CreateJavaVM.
455 static bool create_main_thread(JavaThread* thread);
456
457 // The primordial thread is the initial process thread. The java
458 // launcher never uses the primordial thread as the main thread, but
459 // applications that host the JVM directly may do so. Some platforms
460 // need special-case handling of the primordial thread if it attaches
461 // to the VM.
462 static bool is_primordial_thread(void)
463 #if defined(_WINDOWS) || defined(BSD)
464 // No way to identify the primordial thread.
465 { return false; }
466 #else
467 ;
468 #endif
469
470 static bool create_attached_thread(JavaThread* thread);
471 static void pd_start_thread(Thread* thread);
472 static void start_thread(Thread* thread);
473
474 static void initialize_thread(Thread* thr);
475 static void free_thread(OSThread* osthread);
476
477 // thread id on Linux/64bit is 64bit, on Windows and Solaris, it's 32bit
478 static intx current_thread_id();
479 static int current_process_id();
480 static int sleep(Thread* thread, jlong ms, bool interruptable);
481 // Short standalone OS sleep suitable for slow path spin loop.
482 // Ignores Thread.interrupt() (so keep it short).
483 // ms = 0, will sleep for the least amount of time allowed by the OS.
484 static void naked_short_sleep(jlong ms);
485 static void infinite_sleep(); // never returns, use with CAUTION
486 static void yield(); // Yields to all threads with same priority
487 enum YieldResult {
488 YIELD_SWITCHED = 1, // caller descheduled, other ready threads exist & ran
489 YIELD_NONEREADY = 0, // No other runnable/ready threads.
490 // platform-specific yield return immediately
491 YIELD_UNKNOWN = -1 // Unknown: platform doesn't support _SWITCHED or _NONEREADY
492 // YIELD_SWITCHED and YIELD_NONREADY imply the platform supports a "strong"
493 // yield that can be used in lieu of blocking.
494 } ;
495 static YieldResult NakedYield () ;
496 static void yield_all(int attempts = 0); // Yields to all other threads including lower priority
497 static void loop_breaker(int attempts); // called from within tight loops to possibly influence time-sharing
498 static OSReturn set_priority(Thread* thread, ThreadPriority priority);
499 static OSReturn get_priority(const Thread* const thread, ThreadPriority& priority);
500
501 static void interrupt(Thread* thread);
502 static bool is_interrupted(Thread* thread, bool clear_interrupted);
503
504 static int pd_self_suspend_thread(Thread* thread);
505
506 static ExtendedPC fetch_frame_from_context(void* ucVoid, intptr_t** sp, intptr_t** fp);
507 static frame fetch_frame_from_context(void* ucVoid);
508
509 static ExtendedPC get_thread_pc(Thread *thread);
510 static void breakpoint();
511
512 static address current_stack_pointer();
513 static address current_stack_base();
514 static size_t current_stack_size();
515
516 static void verify_stack_alignment() PRODUCT_RETURN;
517
518 static int message_box(const char* title, const char* message);
519 static char* do_you_want_to_debug(const char* message);
520
521 // run cmd in a separate process and return its exit code; or -1 on failures
522 static int fork_and_exec(char *cmd);
523
524 // os::exit() is merged with vm_exit()
525 // static void exit(int num);
526
527 // Terminate the VM, but don't exit the process
528 static void shutdown();
529
530 // Terminate with an error. Default is to generate a core file on platforms
531 // that support such things. This calls shutdown() and then aborts.
532 static void abort(bool dump_core = true);
533
534 // Die immediately, no exit hook, no abort hook, no cleanup.
535 static void die();
536
537 // File i/o operations
538 static const int default_file_open_flags();
539 static int open(const char *path, int oflag, int mode);
540 static FILE* open(int fd, const char* mode);
541 static int close(int fd);
542 static jlong lseek(int fd, jlong offset, int whence);
543 static char* native_path(char *path);
544 static int ftruncate(int fd, jlong length);
545 static int fsync(int fd);
546 static int available(int fd, jlong *bytes);
547
548 //File i/o operations
549
550 static size_t read(int fd, void *buf, unsigned int nBytes);
551 static size_t restartable_read(int fd, void *buf, unsigned int nBytes);
552 static size_t write(int fd, const void *buf, unsigned int nBytes);
553
554 // Reading directories.
555 static DIR* opendir(const char* dirname);
556 static int readdir_buf_size(const char *path);
557 static struct dirent* readdir(DIR* dirp, dirent* dbuf);
558 static int closedir(DIR* dirp);
559
560 // Dynamic library extension
561 static const char* dll_file_extension();
562
563 static const char* get_temp_directory();
564 static const char* get_current_directory(char *buf, size_t buflen);
565
566 // Builds a platform-specific full library path given a ld path and lib name
567 // Returns true if buffer contains full path to existing file, false otherwise
568 static bool dll_build_name(char* buffer, size_t size,
569 const char* pathname, const char* fname);
570
571 // Symbol lookup, find nearest function name; basically it implements
572 // dladdr() for all platforms. Name of the nearest function is copied
573 // to buf. Distance from its base address is optionally returned as offset.
574 // If function name is not found, buf[0] is set to '\0' and offset is
575 // set to -1 (if offset is non-NULL).
576 static bool dll_address_to_function_name(address addr, char* buf,
577 int buflen, int* offset);
578
579 // Locate DLL/DSO. On success, full path of the library is copied to
580 // buf, and offset is optionally set to be the distance between addr
581 // and the library's base address. On failure, buf[0] is set to '\0'
582 // and offset is set to -1 (if offset is non-NULL).
583 static bool dll_address_to_library_name(address addr, char* buf,
584 int buflen, int* offset);
585
586 // Find out whether the pc is in the static code for jvm.dll/libjvm.so.
587 static bool address_is_in_vm(address addr);
588
589 // Loads .dll/.so and
590 // in case of error it checks if .dll/.so was built for the
591 // same architecture as Hotspot is running on
592 static void* dll_load(const char *name, char *ebuf, int ebuflen);
593
594 // lookup symbol in a shared library
595 static void* dll_lookup(void* handle, const char* name);
596
597 // Unload library
598 static void dll_unload(void *lib);
599
600 // Return the handle of this process
601 static void* get_default_process_handle();
602
603 // Check for static linked agent library
604 static bool find_builtin_agent(AgentLibrary *agent_lib, const char *syms[],
605 size_t syms_len);
606
607 // Find agent entry point
608 static void *find_agent_function(AgentLibrary *agent_lib, bool check_lib,
609 const char *syms[], size_t syms_len);
610
611 // Print out system information; they are called by fatal error handler.
612 // Output format may be different on different platforms.
613 static void print_os_info(outputStream* st);
614 static void print_os_info_brief(outputStream* st);
615 static void print_cpu_info(outputStream* st);
616 static void pd_print_cpu_info(outputStream* st);
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, char* buffer, int len);
620 static void print_context(outputStream* st, void* context);
621 static void print_register_info(outputStream* st, void* context);
622 static void print_siginfo(outputStream* st, void* siginfo);
623 static void print_signal_handlers(outputStream* st, char* buf, size_t buflen);
624 static void print_date_and_time(outputStream* st);
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 // Determines whether the calling process is being debugged by a user-mode debugger.
631 static bool is_debugger_attached();
632
633 // wait for a key press if PauseAtExit is set
634 static void wait_for_keypress_at_exit(void);
635
636 // The following two functions are used by fatal error handler to trace
637 // native (C) frames. They are not part of frame.hpp/frame.cpp because
638 // frame.hpp/cpp assume thread is JavaThread, and also because different
639 // OS/compiler may have different convention or provide different API to
640 // walk C frames.
641 //
642 // We don't attempt to become a debugger, so we only follow frames if that
643 // does not require a lookup in the unwind table, which is part of the binary
644 // file but may be unsafe to read after a fatal error. So on x86, we can
645 // only walk stack if %ebp is used as frame pointer; on ia64, it's not
646 // possible to walk C stack without having the unwind table.
647 static bool is_first_C_frame(frame *fr);
648 static frame get_sender_for_C_frame(frame *fr);
649
650 // return current frame. pc() and sp() are set to NULL on failure.
651 static frame current_frame();
652
653 static void print_hex_dump(outputStream* st, address start, address end, int unitsize);
654
655 // returns a string to describe the exception/signal;
656 // returns NULL if exception_code is not an OS exception/signal.
657 static const char* exception_name(int exception_code, char* buf, size_t buflen);
658
659 // Returns native Java library, loads if necessary
660 static void* native_java_library();
661
662 // Fills in path to jvm.dll/libjvm.so (used by the Disassembler)
663 static void jvm_path(char *buf, jint buflen);
664
665 // Returns true if we are running in a headless jre.
666 static bool is_headless_jre();
667
668 // JNI names
669 static void print_jni_name_prefix_on(outputStream* st, int args_size);
670 static void print_jni_name_suffix_on(outputStream* st, int args_size);
671
672 // File conventions
673 static const char* file_separator();
674 static const char* line_separator();
675 static const char* path_separator();
676
677 // Init os specific system properties values
678 static void init_system_properties_values();
679
680 // IO operations, non-JVM_ version.
681 static int stat(const char* path, struct stat* sbuf);
682 static bool dir_is_empty(const char* path);
683
684 // IO operations on binary files
685 static int create_binary_file(const char* path, bool rewrite_existing);
686 static jlong current_file_offset(int fd);
687 static jlong seek_to_file_offset(int fd, jlong offset);
688
689 // Thread Local Storage
690 static int allocate_thread_local_storage();
691 static void thread_local_storage_at_put(int index, void* value);
692 static void* thread_local_storage_at(int index);
693 static void free_thread_local_storage(int index);
694
695 // Retrieve native stack frames.
696 // Parameter:
697 // stack: an array to storage stack pointers.
698 // frames: size of above array.
699 // toSkip: number of stack frames to skip at the beginning.
700 // Return: number of stack frames captured.
701 static int get_native_stack(address* stack, int size, int toSkip = 0);
702
703 // General allocation (must be MT-safe)
704 static void* malloc (size_t size, MEMFLAGS flags, const NativeCallStack& stack);
705 static void* malloc (size_t size, MEMFLAGS flags);
706 static void* realloc (void *memblock, size_t size, MEMFLAGS flag, const NativeCallStack& stack);
707 static void* realloc (void *memblock, size_t size, MEMFLAGS flag);
708
709 static void free (void *memblock, MEMFLAGS flags = mtNone);
710 static bool check_heap(bool force = false); // verify C heap integrity
711 static char* strdup(const char *, MEMFLAGS flags = mtInternal); // Like strdup
712
713 #ifndef PRODUCT
714 static julong num_mallocs; // # of calls to malloc/realloc
715 static julong alloc_bytes; // # of bytes allocated
716 static julong num_frees; // # of calls to free
717 static julong free_bytes; // # of bytes freed
718 #endif
719
720 // SocketInterface (ex HPI SocketInterface )
721 static int socket(int domain, int type, int protocol);
722 static int socket_close(int fd);
723 static int socket_shutdown(int fd, int howto);
724 static int recv(int fd, char* buf, size_t nBytes, uint flags);
725 static int send(int fd, char* buf, size_t nBytes, uint flags);
726 static int raw_send(int fd, char* buf, size_t nBytes, uint flags);
727 static int timeout(int fd, long timeout);
728 static int listen(int fd, int count);
729 static int connect(int fd, struct sockaddr* him, socklen_t len);
730 static int bind(int fd, struct sockaddr* him, socklen_t len);
731 static int accept(int fd, struct sockaddr* him, socklen_t* len);
732 static int recvfrom(int fd, char* buf, size_t nbytes, uint flags,
733 struct sockaddr* from, socklen_t* fromlen);
734 static int get_sock_name(int fd, struct sockaddr* him, socklen_t* len);
735 static int sendto(int fd, char* buf, size_t len, uint flags,
736 struct sockaddr* to, socklen_t tolen);
737 static int socket_available(int fd, jint* pbytes);
738
739 static int get_sock_opt(int fd, int level, int optname,
740 char* optval, socklen_t* optlen);
741 static int set_sock_opt(int fd, int level, int optname,
742 const char* optval, socklen_t optlen);
743 static int get_host_name(char* name, int namelen);
744
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, methodHandle* method, JavaCallArguments* args, Thread* thread);
765
766 // On Windows this will create an actual minidump, on Linux/Solaris it will simply check core dump limits
767 static void check_or_create_dump(void* exceptionRecord, void* contextRecord, char* buffer, size_t bufferSize);
768
769 // Get the default path to the core file
770 // Returns the length of the string
771 static int get_core_path(char* buffer, size_t bufferSize);
772
773 // JVMTI & JVM monitoring and management support
774 // The thread_cpu_time() and current_thread_cpu_time() are only
775 // supported if is_thread_cpu_time_supported() returns true.
776 // They are not supported on Solaris T1.
777
778 // Thread CPU Time - return the fast estimate on a platform
779 // On Solaris - call gethrvtime (fast) - user time only
780 // On Linux - fast clock_gettime where available - user+sys
781 // - otherwise: very slow /proc fs - user+sys
782 // On Windows - GetThreadTimes - user+sys
783 static jlong current_thread_cpu_time();
784 static jlong thread_cpu_time(Thread* t);
785
786 // Thread CPU Time with user_sys_cpu_time parameter.
787 //
788 // If user_sys_cpu_time is true, user+sys time is returned.
789 // Otherwise, only user time is returned
790 static jlong current_thread_cpu_time(bool user_sys_cpu_time);
791 static jlong thread_cpu_time(Thread* t, bool user_sys_cpu_time);
792
793 // Return a bunch of info about the timers.
794 // Note that the returned info for these two functions may be different
795 // on some platforms
796 static void current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr);
797 static void thread_cpu_time_info(jvmtiTimerInfo *info_ptr);
798
799 static bool is_thread_cpu_time_supported();
800
801 // System loadavg support. Returns -1 if load average cannot be obtained.
802 static int loadavg(double loadavg[], int nelem);
803
804 // Hook for os specific jvm options that we don't want to abort on seeing
805 static bool obsolete_option(const JavaVMOption *option);
806
807 // Extensions
808 #include "runtime/os_ext.hpp"
809
810 public:
811 class CrashProtectionCallback : public StackObj {
812 public:
813 virtual void call() = 0;
814 };
815
816 // Platform dependent stuff
817 #ifdef TARGET_OS_FAMILY_linux
818 # include "os_linux.hpp"
819 # include "os_posix.hpp"
820 #endif
821 #ifdef TARGET_OS_FAMILY_solaris
822 # include "os_solaris.hpp"
823 # include "os_posix.hpp"
824 #endif
825 #ifdef TARGET_OS_FAMILY_windows
826 # include "os_windows.hpp"
827 #endif
828 #ifdef TARGET_OS_FAMILY_aix
829 # include "os_aix.hpp"
830 # include "os_posix.hpp"
831 #endif
832 #ifdef TARGET_OS_FAMILY_bsd
833 # include "os_posix.hpp"
834 # include "os_bsd.hpp"
835 #endif
836 #ifdef TARGET_OS_ARCH_linux_x86
837 # include "os_linux_x86.hpp"
838 #endif
839 #ifdef TARGET_OS_ARCH_linux_sparc
840 # include "os_linux_sparc.hpp"
841 #endif
842 #ifdef TARGET_OS_ARCH_linux_zero
843 # include "os_linux_zero.hpp"
844 #endif
845 #ifdef TARGET_OS_ARCH_solaris_x86
846 # include "os_solaris_x86.hpp"
847 #endif
848 #ifdef TARGET_OS_ARCH_solaris_sparc
849 # include "os_solaris_sparc.hpp"
850 #endif
851 #ifdef TARGET_OS_ARCH_windows_x86
852 # include "os_windows_x86.hpp"
853 #endif
854 #ifdef TARGET_OS_ARCH_linux_arm
855 # include "os_linux_arm.hpp"
856 #endif
857 #ifdef TARGET_OS_ARCH_linux_ppc
858 # include "os_linux_ppc.hpp"
859 #endif
860 #ifdef TARGET_OS_ARCH_aix_ppc
861 # include "os_aix_ppc.hpp"
862 #endif
863 #ifdef TARGET_OS_ARCH_bsd_x86
864 # include "os_bsd_x86.hpp"
865 #endif
866 #ifdef TARGET_OS_ARCH_bsd_zero
867 # include "os_bsd_zero.hpp"
868 #endif
869
870 public:
871 #ifndef PLATFORM_PRINT_NATIVE_STACK
872 // No platform-specific code for printing the native stack.
873 static bool platform_print_native_stack(outputStream* st, void* context,
874 char *buf, int buf_size) {
875 return false;
876 }
877 #endif
878
879 // debugging support (mostly used by debug.cpp but also fatal error handler)
880 static bool find(address pc, outputStream* st = tty); // OS specific function to make sense out of an address
881
882 static bool dont_yield(); // when true, JVM_Yield() is nop
883 static void print_statistics();
884
885 // Thread priority helpers (implemented in OS-specific part)
886 static OSReturn set_native_priority(Thread* thread, int native_prio);
887 static OSReturn get_native_priority(const Thread* const thread, int* priority_ptr);
888 static int java_to_os_priority[CriticalPriority + 1];
889 // Hint to the underlying OS that a task switch would not be good.
890 // Void return because it's a hint and can fail.
891 static void hint_no_preempt();
892
893 // Used at creation if requested by the diagnostic flag PauseAtStartup.
894 // Causes the VM to wait until an external stimulus has been applied
895 // (for Unix, that stimulus is a signal, for Windows, an external
896 // ResumeThread call)
897 static void pause();
898
899 // Builds a platform dependent Agent_OnLoad_<libname> function name
900 // which is used to find statically linked in agents.
901 static char* build_agent_function_name(const char *sym, const char *cname,
902 bool is_absolute_path);
903
904 class SuspendedThreadTaskContext {
905 public:
906 SuspendedThreadTaskContext(Thread* thread, void *ucontext) : _thread(thread), _ucontext(ucontext) {}
907 Thread* thread() const { return _thread; }
908 void* ucontext() const { return _ucontext; }
909 private:
910 Thread* _thread;
911 void* _ucontext;
912 };
913
914 class SuspendedThreadTask {
915 public:
916 SuspendedThreadTask(Thread* thread) : _thread(thread), _done(false) {}
917 virtual ~SuspendedThreadTask() {}
918 void run();
919 bool is_done() { return _done; }
920 virtual void do_task(const SuspendedThreadTaskContext& context) = 0;
921 protected:
922 private:
923 void internal_do_task();
924 Thread* _thread;
925 bool _done;
926 };
927
928 #ifndef TARGET_OS_FAMILY_windows
929 // Suspend/resume support
930 // Protocol:
931 //
932 // a thread starts in SR_RUNNING
933 //
934 // SR_RUNNING can go to
935 // * SR_SUSPEND_REQUEST when the WatcherThread wants to suspend it
936 // SR_SUSPEND_REQUEST can go to
937 // * SR_RUNNING if WatcherThread decides it waited for SR_SUSPENDED too long (timeout)
938 // * SR_SUSPENDED if the stopped thread receives the signal and switches state
939 // SR_SUSPENDED can go to
940 // * SR_WAKEUP_REQUEST when the WatcherThread has done the work and wants to resume
941 // SR_WAKEUP_REQUEST can go to
942 // * SR_RUNNING when the stopped thread receives the signal
943 // * SR_WAKEUP_REQUEST on timeout (resend the signal and try again)
944 class SuspendResume {
945 public:
946 enum State {
947 SR_RUNNING,
948 SR_SUSPEND_REQUEST,
949 SR_SUSPENDED,
950 SR_WAKEUP_REQUEST
951 };
952
953 private:
954 volatile State _state;
955
956 private:
957 /* try to switch state from state "from" to state "to"
958 * returns the state set after the method is complete
959 */
960 State switch_state(State from, State to);
961
962 public:
963 SuspendResume() : _state(SR_RUNNING) { }
964
965 State state() const { return _state; }
966
967 State request_suspend() {
968 return switch_state(SR_RUNNING, SR_SUSPEND_REQUEST);
969 }
970
971 State cancel_suspend() {
972 return switch_state(SR_SUSPEND_REQUEST, SR_RUNNING);
973 }
974
975 State suspended() {
976 return switch_state(SR_SUSPEND_REQUEST, SR_SUSPENDED);
977 }
978
979 State request_wakeup() {
980 return switch_state(SR_SUSPENDED, SR_WAKEUP_REQUEST);
981 }
982
983 State running() {
984 return switch_state(SR_WAKEUP_REQUEST, SR_RUNNING);
985 }
986
987 bool is_running() const {
988 return _state == SR_RUNNING;
989 }
990
991 bool is_suspend_request() const {
992 return _state == SR_SUSPEND_REQUEST;
993 }
994
995 bool is_suspended() const {
996 return _state == SR_SUSPENDED;
997 }
998 };
999 #endif
1000
1001
1002 protected:
1003 static long _rand_seed; // seed for random number generator
1004 static int _processor_count; // number of processors
1005 static int _initial_active_processor_count; // number of active processors during initialization.
1006
1007 static char* format_boot_path(const char* format_string,
1008 const char* home,
1009 int home_len,
1010 char fileSep,
1011 char pathSep);
1012 static bool set_boot_path(char fileSep, char pathSep);
1013 static char** split_path(const char* path, int* n);
1014
1015 };
1016
1017 // Note that "PAUSE" is almost always used with synchronization
1018 // so arguably we should provide Atomic::SpinPause() instead
1019 // of the global SpinPause() with C linkage.
1020 // It'd also be eligible for inlining on many platforms.
1021
1022 extern "C" int SpinPause();
1023
1024 #endif // SHARE_VM_RUNTIME_OS_HPP