1 /*
2 * Copyright (c) 1997, 2014, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #ifndef SHARE_VM_RUNTIME_OS_HPP
26 #define SHARE_VM_RUNTIME_OS_HPP
27
28 #include "jvmtifiles/jvmti.h"
29 #include "runtime/extendedPC.hpp"
30 #include "runtime/handles.hpp"
31 #include "utilities/top.hpp"
32 #ifdef TARGET_OS_FAMILY_linux
33 # include "jvm_linux.h"
34 # include <setjmp.h>
35 #endif
36 #ifdef TARGET_OS_FAMILY_solaris
37 # include "jvm_solaris.h"
38 # include <setjmp.h>
39 #endif
40 #ifdef TARGET_OS_FAMILY_windows
41 # include "jvm_windows.h"
42 #endif
43 #ifdef TARGET_OS_FAMILY_aix
44 # include "jvm_aix.h"
45 # include <setjmp.h>
46 #endif
47 #ifdef TARGET_OS_FAMILY_bsd
48 # include "jvm_bsd.h"
49 # include <setjmp.h>
50 # ifdef __APPLE__
51 # include <mach/mach_time.h>
52 # endif
53 #endif
54
55 class AgentLibrary;
56
57 // os defines the interface to operating system; this includes traditional
58 // OS services (time, I/O) as well as other functionality with system-
59 // dependent code.
60
61 typedef void (*dll_func)(...);
62
63 class Thread;
64 class JavaThread;
65 class Event;
66 class DLL;
67 class FileHandle;
68 class NativeCallStack;
69
70 template<class E> class GrowableArray;
71
72 // %%%%% Moved ThreadState, START_FN, OSThread to new osThread.hpp. -- Rose
73
74 // Platform-independent error return values from OS functions
75 enum OSReturn {
76 OS_OK = 0, // Operation was successful
77 OS_ERR = -1, // Operation failed
78 OS_INTRPT = -2, // Operation was interrupted
79 OS_TIMEOUT = -3, // Operation timed out
80 OS_NOMEM = -5, // Operation failed for lack of memory
81 OS_NORESOURCE = -6 // Operation failed for lack of nonmemory resource
82 };
83
84 enum ThreadPriority { // JLS 20.20.1-3
85 NoPriority = -1, // Initial non-priority value
86 MinPriority = 1, // Minimum priority
87 NormPriority = 5, // Normal (non-daemon) priority
88 NearMaxPriority = 9, // High priority, used for VMThread
89 MaxPriority = 10, // Highest priority, used for WatcherThread
90 // ensures that VMThread doesn't starve profiler
91 CriticalPriority = 11 // Critical thread priority
92 };
93
94 // Executable parameter flag for os::commit_memory() and
95 // os::commit_memory_or_exit().
96 const bool ExecMem = true;
97
98 // Typedef for structured exception handling support
99 typedef void (*java_call_t)(JavaValue* value, methodHandle* method, JavaCallArguments* args, Thread* thread);
100
101 class MallocTracker;
102
103 class os: AllStatic {
104 friend class VMStructs;
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
152 public:
153 static void init(void); // Called before command line parsing
154 static void init_before_ergo(void); // Called after command line parsing
155 // before VM ergonomics processing.
156 static jint init_2(void); // Called after command line parsing
157 // and VM ergonomics processing
158 static void init_globals(void) { // Called from init_globals() in init.cpp
159 init_globals_ext();
160 }
161 static void init_3(void); // Called at the end of vm init
162
163 // File names are case-insensitive on windows only
164 // Override me as needed
165 static int file_name_strcmp(const char* s1, const char* s2);
166
167 // get/unset environment variable
168 static bool getenv(const char* name, char* buffer, int len);
169 static bool unsetenv(const char* name);
170
171 static bool have_special_privileges();
172
173 static jlong javaTimeMillis();
174 static jlong javaTimeNanos();
175 static void javaTimeNanos_info(jvmtiTimerInfo *info_ptr);
176 static void run_periodic_checks();
177 static bool supports_monotonic_clock();
178
179
180 // Returns the elapsed time in seconds since the vm started.
181 static double elapsedTime();
182
183 // Returns real time in seconds since an arbitrary point
184 // in the past.
185 static bool getTimesSecs(double* process_real_time,
186 double* process_user_time,
187 double* process_system_time);
188
189 // Interface to the performance counter
190 static jlong elapsed_counter();
191 static jlong elapsed_frequency();
192
193 // The "virtual time" of a thread is the amount of time a thread has
194 // actually run. The first function indicates whether the OS supports
195 // this functionality for the current thread, and if so:
196 // * the second enables vtime tracking (if that is required).
197 // * the third tells whether vtime is enabled.
198 // * the fourth returns the elapsed virtual time for the current
199 // thread.
200 static bool supports_vtime();
201 static bool enable_vtime();
202 static bool vtime_enabled();
203 static double elapsedVTime();
204
205 // Return current local time in a string (YYYY-MM-DD HH:MM:SS).
206 // It is MT safe, but not async-safe, as reading time zone
207 // information may require a lock on some platforms.
208 static char* local_time_string(char *buf, size_t buflen);
209 static struct tm* localtime_pd (const time_t* clock, struct tm* res);
210 // Fill in buffer with current local time as an ISO-8601 string.
211 // E.g., YYYY-MM-DDThh:mm:ss.mmm+zzzz.
212 // Returns buffer, or NULL if it failed.
213 static char* iso8601_time(char* buffer, size_t buffer_length);
214
215 // Interface for detecting multiprocessor system
216 static inline bool is_MP() {
217 // During bootstrap if _processor_count is not yet initialized
218 // we claim to be MP as that is safest. If any platform has a
219 // stub generator that might be triggered in this phase and for
220 // which being declared MP when in fact not, is a problem - then
221 // the bootstrap routine for the stub generator needs to check
222 // the processor count directly and leave the bootstrap routine
223 // in place until called after initialization has ocurred.
224 return (_processor_count != 1) || AssumeMP;
225 }
226 static julong available_memory();
227 static julong physical_memory();
228 static bool has_allocatable_memory_limit(julong* limit);
229 static bool is_server_class_machine();
230
231 // number of CPUs
232 static int processor_count() {
233 return _processor_count;
234 }
235 static void set_processor_count(int count) { _processor_count = count; }
236
237 // Returns the number of CPUs this process is currently allowed to run on.
238 // Note that on some OSes this can change dynamically.
239 static int active_processor_count();
240
241 // Bind processes to processors.
242 // This is a two step procedure:
243 // first you generate a distribution of processes to processors,
244 // then you bind processes according to that distribution.
245 // Compute a distribution for number of processes to processors.
246 // Stores the processor id's into the distribution array argument.
247 // Returns true if it worked, false if it didn't.
248 static bool distribute_processes(uint length, uint* distribution);
249 // Binds the current process to a processor.
250 // Returns true if it worked, false if it didn't.
251 static bool bind_to_processor(uint processor_id);
252
253 // Give a name to the current thread.
254 static void set_native_thread_name(const char *name);
255
256 // Interface for stack banging (predetect possible stack overflow for
257 // exception processing) There are guard pages, and above that shadow
258 // pages for stack overflow checking.
259 static bool uses_stack_guard_pages();
260 static bool allocate_stack_guard_pages();
261 static void bang_stack_shadow_pages();
262 static bool stack_shadow_pages_available(Thread *thread, methodHandle method);
263
264 // OS interface to Virtual Memory
265
266 // Return the default page size.
267 static int vm_page_size();
268
269 // Returns the page size to use for a region of memory.
270 // region_size / min_pages will always be greater than or equal to the
271 // returned value.
272 static size_t page_size_for_region(size_t region_size, size_t min_pages);
273
274 // Return the largest page size that can be used
275 static size_t max_page_size() {
276 // The _page_sizes array is sorted in descending order.
277 return _page_sizes[0];
278 }
279
280 // Methods for tracing page sizes returned by the above method; enabled by
281 // TracePageSizes. The region_{min,max}_size parameters should be the values
282 // passed to page_size_for_region() and page_size should be the result of that
283 // call. The (optional) base and size parameters should come from the
284 // ReservedSpace base() and size() methods.
285 static void trace_page_sizes(const char* str, const size_t* page_sizes,
286 int count) PRODUCT_RETURN;
287 static void trace_page_sizes(const char* str, const size_t region_min_size,
288 const size_t region_max_size,
289 const size_t page_size,
290 const char* base = NULL,
291 const size_t size = 0) PRODUCT_RETURN;
292
293 static int vm_allocation_granularity();
294 static char* reserve_memory(size_t bytes, char* addr = 0,
295 size_t alignment_hint = 0);
296 static char* reserve_memory(size_t bytes, char* addr,
297 size_t alignment_hint, MEMFLAGS flags);
298 static char* reserve_memory_aligned(size_t size, size_t alignment);
299 static char* attempt_reserve_memory_at(size_t bytes, char* addr);
300 static void split_reserved_memory(char *base, size_t size,
301 size_t split, bool realloc);
302 static bool commit_memory(char* addr, size_t bytes, bool executable);
303 static bool commit_memory(char* addr, size_t size, size_t alignment_hint,
304 bool executable);
305 // Same as commit_memory() that either succeeds or calls
306 // vm_exit_out_of_memory() with the specified mesg.
307 static void commit_memory_or_exit(char* addr, size_t bytes,
308 bool executable, const char* mesg);
309 static void commit_memory_or_exit(char* addr, size_t size,
310 size_t alignment_hint,
311 bool executable, const char* mesg);
312 static bool uncommit_memory(char* addr, size_t bytes);
313 static bool release_memory(char* addr, size_t bytes);
314
315 enum ProtType { MEM_PROT_NONE, MEM_PROT_READ, MEM_PROT_RW, MEM_PROT_RWX };
316 static bool protect_memory(char* addr, size_t bytes, ProtType prot,
317 bool is_committed = true);
318
319 static bool guard_memory(char* addr, size_t bytes);
320 static bool unguard_memory(char* addr, size_t bytes);
321 static bool create_stack_guard_pages(char* addr, size_t bytes);
322 static bool pd_create_stack_guard_pages(char* addr, size_t bytes);
323 static bool remove_stack_guard_pages(char* addr, size_t bytes);
324
325 static char* map_memory(int fd, const char* file_name, size_t file_offset,
326 char *addr, size_t bytes, bool read_only = false,
327 bool allow_exec = false);
328 static char* remap_memory(int fd, const char* file_name, size_t file_offset,
329 char *addr, size_t bytes, bool read_only,
330 bool allow_exec);
331 static bool unmap_memory(char *addr, size_t bytes);
332 static void free_memory(char *addr, size_t bytes, size_t alignment_hint);
333 static void realign_memory(char *addr, size_t bytes, size_t alignment_hint);
334
335 // NUMA-specific interface
336 static bool numa_has_static_binding();
337 static bool numa_has_group_homing();
338 static void numa_make_local(char *addr, size_t bytes, int lgrp_hint);
339 static void numa_make_global(char *addr, size_t bytes);
340 static size_t numa_get_groups_num();
341 static size_t numa_get_leaf_groups(int *ids, size_t size);
342 static bool numa_topology_changed();
343 static int numa_get_group_id();
344
345 // Page manipulation
346 struct page_info {
347 size_t size;
348 int lgrp_id;
349 };
350 static bool get_page_info(char *start, page_info* info);
351 static char* scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found);
352
353 static char* non_memory_address_word();
354 // reserve, commit and pin the entire memory region
355 static char* reserve_memory_special(size_t size, size_t alignment,
356 char* addr, bool executable);
357 static bool release_memory_special(char* addr, size_t bytes);
358 static void large_page_init();
359 static size_t large_page_size();
360 static bool can_commit_large_page_memory();
361 static bool can_execute_large_page_memory();
362
363 // OS interface to polling page
364 static address get_polling_page() { return _polling_page; }
365 static void set_polling_page(address page) { _polling_page = page; }
366 static bool is_poll_address(address addr) { return addr >= _polling_page && addr < (_polling_page + os::vm_page_size()); }
367 static void make_polling_page_unreadable();
368 static void make_polling_page_readable();
369
370 // Routines used to serialize the thread state without using membars
371 static void serialize_thread_states();
372
373 // Since we write to the serialize page from every thread, we
374 // want stores to be on unique cache lines whenever possible
375 // in order to minimize CPU cross talk. We pre-compute the
376 // amount to shift the thread* to make this offset unique to
377 // each thread.
378 static int get_serialize_page_shift_count() {
379 return SerializePageShiftCount;
380 }
381
382 static void set_serialize_page_mask(uintptr_t mask) {
383 _serialize_page_mask = mask;
384 }
385
386 static unsigned int get_serialize_page_mask() {
387 return _serialize_page_mask;
388 }
389
390 static void set_memory_serialize_page(address page);
391
392 static address get_memory_serialize_page() {
393 return (address)_mem_serialize_page;
394 }
395
396 static inline void write_memory_serialize_page(JavaThread *thread) {
397 uintptr_t page_offset = ((uintptr_t)thread >>
398 get_serialize_page_shift_count()) &
399 get_serialize_page_mask();
400 *(volatile int32_t *)((uintptr_t)_mem_serialize_page+page_offset) = 1;
401 }
402
403 static bool is_memory_serialize_page(JavaThread *thread, address addr) {
404 if (UseMembar) return false;
405 // Previously this function calculated the exact address of this
406 // thread's serialize page, and checked if the faulting address
407 // was equal. However, some platforms mask off faulting addresses
408 // to the page size, so now we just check that the address is
409 // within the page. This makes the thread argument unnecessary,
410 // but we retain the NULL check to preserve existing behavior.
411 if (thread == NULL) return false;
412 address page = (address) _mem_serialize_page;
413 return addr >= page && addr < (page + os::vm_page_size());
414 }
415
416 static void block_on_serialize_page_trap();
417
418 // threads
419
420 enum ThreadType {
421 vm_thread,
422 cgc_thread, // Concurrent GC thread
423 pgc_thread, // Parallel GC thread
424 java_thread,
425 compiler_thread,
426 watcher_thread,
427 os_thread
428 };
429
430 static bool create_thread(Thread* thread,
431 ThreadType thr_type,
432 size_t stack_size = 0);
433 static bool create_main_thread(JavaThread* thread);
434 static bool create_attached_thread(JavaThread* thread);
435 static void pd_start_thread(Thread* thread);
436 static void start_thread(Thread* thread);
437
438 static void initialize_thread(Thread* thr);
439 static void free_thread(OSThread* osthread);
440
441 // thread id on Linux/64bit is 64bit, on Windows and Solaris, it's 32bit
442 static intx current_thread_id();
443 static int current_process_id();
444 static int sleep(Thread* thread, jlong ms, bool interruptable);
445 // Short standalone OS sleep suitable for slow path spin loop.
446 // Ignores Thread.interrupt() (so keep it short).
447 // ms = 0, will sleep for the least amount of time allowed by the OS.
448 static void naked_short_sleep(jlong ms);
449 static void infinite_sleep(); // never returns, use with CAUTION
450 static void naked_yield () ;
451 static OSReturn set_priority(Thread* thread, ThreadPriority priority);
452 static OSReturn get_priority(const Thread* const thread, ThreadPriority& priority);
453
454 static void interrupt(Thread* thread);
455 static bool is_interrupted(Thread* thread, bool clear_interrupted);
456
457 static int pd_self_suspend_thread(Thread* thread);
458
459 static ExtendedPC fetch_frame_from_context(void* ucVoid, intptr_t** sp, intptr_t** fp);
460 static frame fetch_frame_from_context(void* ucVoid);
461
462 static ExtendedPC get_thread_pc(Thread *thread);
463 static void breakpoint();
464
465 static address current_stack_pointer();
466 static address current_stack_base();
467 static size_t current_stack_size();
468
469 static void verify_stack_alignment() PRODUCT_RETURN;
470
471 static int message_box(const char* title, const char* message);
472 static char* do_you_want_to_debug(const char* message);
473
474 // run cmd in a separate process and return its exit code; or -1 on failures
475 static int fork_and_exec(char *cmd);
476
477 // Call ::exit() on all platforms but Windows
478 static void exit(int num);
479
480 // Terminate the VM, but don't exit the process
481 static void shutdown();
482
483 // Terminate with an error. Default is to generate a core file on platforms
484 // that support such things. This calls shutdown() and then aborts.
485 static void abort(bool dump_core = true);
486
487 // Die immediately, no exit hook, no abort hook, no cleanup.
488 static void die();
489
490 // File i/o operations
491 static const int default_file_open_flags();
492 static int open(const char *path, int oflag, int mode);
493 static FILE* open(int fd, const char* mode);
494 static int close(int fd);
495 static jlong lseek(int fd, jlong offset, int whence);
496 static char* native_path(char *path);
497 static int ftruncate(int fd, jlong length);
498 static int fsync(int fd);
499 static int available(int fd, jlong *bytes);
500
501 //File i/o operations
502
503 static size_t read(int fd, void *buf, unsigned int nBytes);
504 static size_t restartable_read(int fd, void *buf, unsigned int nBytes);
505 static size_t write(int fd, const void *buf, unsigned int nBytes);
506
507 // Reading directories.
508 static DIR* opendir(const char* dirname);
509 static int readdir_buf_size(const char *path);
510 static struct dirent* readdir(DIR* dirp, dirent* dbuf);
511 static int closedir(DIR* dirp);
512
513 // Dynamic library extension
514 static const char* dll_file_extension();
515
516 static const char* get_temp_directory();
517 static const char* get_current_directory(char *buf, size_t buflen);
518
519 // Builds a platform-specific full library path given a ld path and lib name
520 // Returns true if buffer contains full path to existing file, false otherwise
521 static bool dll_build_name(char* buffer, size_t size,
522 const char* pathname, const char* fname);
523
524 // Symbol lookup, find nearest function name; basically it implements
525 // dladdr() for all platforms. Name of the nearest function is copied
526 // to buf. Distance from its base address is optionally returned as offset.
527 // If function name is not found, buf[0] is set to '\0' and offset is
528 // set to -1 (if offset is non-NULL).
529 static bool dll_address_to_function_name(address addr, char* buf,
530 int buflen, int* offset);
531
532 // Locate DLL/DSO. On success, full path of the library is copied to
533 // buf, and offset is optionally set to be the distance between addr
534 // and the library's base address. On failure, buf[0] is set to '\0'
535 // and offset is set to -1 (if offset is non-NULL).
536 static bool dll_address_to_library_name(address addr, char* buf,
537 int buflen, int* offset);
538
539 // Find out whether the pc is in the static code for jvm.dll/libjvm.so.
540 static bool address_is_in_vm(address addr);
541
542 // Loads .dll/.so and
543 // in case of error it checks if .dll/.so was built for the
544 // same architecture as HotSpot is running on
545 static void* dll_load(const char *name, char *ebuf, int ebuflen);
546
547 // lookup symbol in a shared library
548 static void* dll_lookup(void* handle, const char* name);
549
550 // Unload library
551 static void dll_unload(void *lib);
552
553 // Callback for loaded module information
554 // Input parameters:
555 // char* module_file_name,
556 // address module_base_addr,
557 // address module_top_addr,
558 // void* param
559 typedef int (*LoadedModulesCallbackFunc)(const char *, address, address, void *);
560
561 static int get_loaded_modules_info(LoadedModulesCallbackFunc callback, void *param);
562
563 // Return the handle of this process
564 static void* get_default_process_handle();
565
566 // Check for static linked agent library
567 static bool find_builtin_agent(AgentLibrary *agent_lib, const char *syms[],
568 size_t syms_len);
569
570 // Find agent entry point
571 static void *find_agent_function(AgentLibrary *agent_lib, bool check_lib,
572 const char *syms[], size_t syms_len);
573
574 // Print out system information; they are called by fatal error handler.
575 // Output format may be different on different platforms.
576 static void print_os_info(outputStream* st);
577 static void print_os_info_brief(outputStream* st);
578 static void print_cpu_info(outputStream* st);
579 static void pd_print_cpu_info(outputStream* st);
580 static void print_memory_info(outputStream* st);
581 static void print_dll_info(outputStream* st);
582 static void print_environment_variables(outputStream* st, const char** env_list, char* buffer, int len);
583 static void print_context(outputStream* st, void* context);
584 static void print_register_info(outputStream* st, void* context);
585 static void print_siginfo(outputStream* st, void* siginfo);
586 static void print_signal_handlers(outputStream* st, char* buf, size_t buflen);
587 static void print_date_and_time(outputStream* st);
588
589 static void print_location(outputStream* st, intptr_t x, bool verbose = false);
590 static size_t lasterror(char *buf, size_t len);
591 static int get_last_error();
592
593 // Determines whether the calling process is being debugged by a user-mode debugger.
594 static bool is_debugger_attached();
595
596 // wait for a key press if PauseAtExit is set
597 static void wait_for_keypress_at_exit(void);
598
599 // The following two functions are used by fatal error handler to trace
600 // native (C) frames. They are not part of frame.hpp/frame.cpp because
601 // frame.hpp/cpp assume thread is JavaThread, and also because different
602 // OS/compiler may have different convention or provide different API to
603 // walk C frames.
604 //
605 // We don't attempt to become a debugger, so we only follow frames if that
606 // does not require a lookup in the unwind table, which is part of the binary
607 // file but may be unsafe to read after a fatal error. So on x86, we can
608 // only walk stack if %ebp is used as frame pointer; on ia64, it's not
609 // possible to walk C stack without having the unwind table.
610 static bool is_first_C_frame(frame *fr);
611 static frame get_sender_for_C_frame(frame *fr);
612
613 // return current frame. pc() and sp() are set to NULL on failure.
614 static frame current_frame();
615
616 static void print_hex_dump(outputStream* st, address start, address end, int unitsize);
617
618 // returns a string to describe the exception/signal;
619 // returns NULL if exception_code is not an OS exception/signal.
620 static const char* exception_name(int exception_code, char* buf, size_t buflen);
621
622 // Returns native Java library, loads if necessary
623 static void* native_java_library();
624
625 // Fills in path to jvm.dll/libjvm.so (used by the Disassembler)
626 static void jvm_path(char *buf, jint buflen);
627
628 // Returns true if we are running in a headless jre.
629 static bool is_headless_jre();
630
631 // JNI names
632 static void print_jni_name_prefix_on(outputStream* st, int args_size);
633 static void print_jni_name_suffix_on(outputStream* st, int args_size);
634
635 // Init os specific system properties values
636 static void init_system_properties_values();
637
638 // IO operations, non-JVM_ version.
639 static int stat(const char* path, struct stat* sbuf);
640 static bool dir_is_empty(const char* path);
641
642 // IO operations on binary files
643 static int create_binary_file(const char* path, bool rewrite_existing);
644 static jlong current_file_offset(int fd);
645 static jlong seek_to_file_offset(int fd, jlong offset);
646
647 // Thread Local Storage
648 static int allocate_thread_local_storage();
649 static void thread_local_storage_at_put(int index, void* value);
650 static void* thread_local_storage_at(int index);
651 static void free_thread_local_storage(int index);
652
653 // Retrieve native stack frames.
654 // Parameter:
655 // stack: an array to storage stack pointers.
656 // frames: size of above array.
657 // toSkip: number of stack frames to skip at the beginning.
658 // Return: number of stack frames captured.
659 static int get_native_stack(address* stack, int size, int toSkip = 0);
660
661 // General allocation (must be MT-safe)
662 static void* malloc (size_t size, MEMFLAGS flags, const NativeCallStack& stack);
663 static void* malloc (size_t size, MEMFLAGS flags);
664 static void* realloc (void *memblock, size_t size, MEMFLAGS flag, const NativeCallStack& stack);
665 static void* realloc (void *memblock, size_t size, MEMFLAGS flag);
666
667 static void free (void *memblock, MEMFLAGS flags = mtNone);
668 static bool check_heap(bool force = false); // verify C heap integrity
669 static char* strdup(const char *, MEMFLAGS flags = mtInternal); // Like strdup
670 // Like strdup, but exit VM when strdup() returns NULL
671 static char* strdup_check_oom(const char*, MEMFLAGS flags = mtInternal);
672
673 #ifndef PRODUCT
674 static julong num_mallocs; // # of calls to malloc/realloc
675 static julong alloc_bytes; // # of bytes allocated
676 static julong num_frees; // # of calls to free
677 static julong free_bytes; // # of bytes freed
678 #endif
679
680 // SocketInterface (ex HPI SocketInterface )
681 static int socket(int domain, int type, int protocol);
682 static int socket_close(int fd);
683 static int socket_shutdown(int fd, int howto);
684 static int recv(int fd, char* buf, size_t nBytes, uint flags);
685 static int send(int fd, char* buf, size_t nBytes, uint flags);
686 static int raw_send(int fd, char* buf, size_t nBytes, uint flags);
687 static int timeout(int fd, long timeout);
688 static int listen(int fd, int count);
689 static int connect(int fd, struct sockaddr* him, socklen_t len);
690 static int bind(int fd, struct sockaddr* him, socklen_t len);
691 static int accept(int fd, struct sockaddr* him, socklen_t* len);
692 static int recvfrom(int fd, char* buf, size_t nbytes, uint flags,
693 struct sockaddr* from, socklen_t* fromlen);
694 static int get_sock_name(int fd, struct sockaddr* him, socklen_t* len);
695 static int sendto(int fd, char* buf, size_t len, uint flags,
696 struct sockaddr* to, socklen_t tolen);
697 static int socket_available(int fd, jint* pbytes);
698
699 static int get_sock_opt(int fd, int level, int optname,
700 char* optval, socklen_t* optlen);
701 static int set_sock_opt(int fd, int level, int optname,
702 const char* optval, socklen_t optlen);
703 static int get_host_name(char* name, int namelen);
704
705 static struct hostent* get_host_by_name(char* name);
706
707 // Support for signals (see JVM_RaiseSignal, JVM_RegisterSignal)
708 static void signal_init();
709 static void signal_init_pd();
710 static void signal_notify(int signal_number);
711 static void* signal(int signal_number, void* handler);
712 static void signal_raise(int signal_number);
713 static int signal_wait();
714 static int signal_lookup();
715 static void* user_handler();
716 static void terminate_signal_thread();
717 static int sigexitnum_pd();
718
719 // random number generation
720 static long random(); // return 32bit pseudorandom number
721 static void init_random(long initval); // initialize random sequence
722
723 // Structured OS Exception support
724 static void os_exception_wrapper(java_call_t f, JavaValue* value, methodHandle* method, JavaCallArguments* args, Thread* thread);
725
726 // On Windows this will create an actual minidump, on Linux/Solaris it will simply check core dump limits
727 static void check_or_create_dump(void* exceptionRecord, void* contextRecord, char* buffer, size_t bufferSize);
728
729 // Get the default path to the core file
730 // Returns the length of the string
731 static int get_core_path(char* buffer, size_t bufferSize);
732
733 // JVMTI & JVM monitoring and management support
734 // The thread_cpu_time() and current_thread_cpu_time() are only
735 // supported if is_thread_cpu_time_supported() returns true.
736 // They are not supported on Solaris T1.
737
738 // Thread CPU Time - return the fast estimate on a platform
739 // On Solaris - call gethrvtime (fast) - user time only
740 // On Linux - fast clock_gettime where available - user+sys
741 // - otherwise: very slow /proc fs - user+sys
742 // On Windows - GetThreadTimes - user+sys
743 static jlong current_thread_cpu_time();
744 static jlong thread_cpu_time(Thread* t);
745
746 // Thread CPU Time with user_sys_cpu_time parameter.
747 //
748 // If user_sys_cpu_time is true, user+sys time is returned.
749 // Otherwise, only user time is returned
750 static jlong current_thread_cpu_time(bool user_sys_cpu_time);
751 static jlong thread_cpu_time(Thread* t, bool user_sys_cpu_time);
752
753 // Return a bunch of info about the timers.
754 // Note that the returned info for these two functions may be different
755 // on some platforms
756 static void current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr);
757 static void thread_cpu_time_info(jvmtiTimerInfo *info_ptr);
758
759 static bool is_thread_cpu_time_supported();
760
761 // System loadavg support. Returns -1 if load average cannot be obtained.
762 static int loadavg(double loadavg[], int nelem);
763
764 // Hook for os specific jvm options that we don't want to abort on seeing
765 static bool obsolete_option(const JavaVMOption *option);
766
767 // Amount beyond the callee frame size that we bang the stack.
768 static int extra_bang_size_in_bytes();
769
770 // Extensions
771 #include "runtime/os_ext.hpp"
772
773 public:
774 class CrashProtectionCallback : public StackObj {
775 public:
776 virtual void call() = 0;
777 };
778
779 // Platform dependent stuff
780 #ifdef TARGET_OS_FAMILY_linux
781 # include "os_linux.hpp"
782 # include "os_posix.hpp"
783 #endif
784 #ifdef TARGET_OS_FAMILY_solaris
785 # include "os_solaris.hpp"
786 # include "os_posix.hpp"
787 #endif
788 #ifdef TARGET_OS_FAMILY_windows
789 # include "os_windows.hpp"
790 #endif
791 #ifdef TARGET_OS_FAMILY_aix
792 # include "os_aix.hpp"
793 # include "os_posix.hpp"
794 #endif
795 #ifdef TARGET_OS_FAMILY_bsd
796 # include "os_posix.hpp"
797 # include "os_bsd.hpp"
798 #endif
799 #ifdef TARGET_OS_ARCH_linux_x86
800 # include "os_linux_x86.hpp"
801 #endif
802 #ifdef TARGET_OS_ARCH_linux_sparc
803 # include "os_linux_sparc.hpp"
804 #endif
805 #ifdef TARGET_OS_ARCH_linux_zero
806 # include "os_linux_zero.hpp"
807 #endif
808 #ifdef TARGET_OS_ARCH_solaris_x86
809 # include "os_solaris_x86.hpp"
810 #endif
811 #ifdef TARGET_OS_ARCH_solaris_sparc
812 # include "os_solaris_sparc.hpp"
813 #endif
814 #ifdef TARGET_OS_ARCH_windows_x86
815 # include "os_windows_x86.hpp"
816 #endif
817 #ifdef TARGET_OS_ARCH_linux_arm
818 # include "os_linux_arm.hpp"
819 #endif
820 #ifdef TARGET_OS_ARCH_linux_ppc
821 # include "os_linux_ppc.hpp"
822 #endif
823 #ifdef TARGET_OS_ARCH_aix_ppc
824 # include "os_aix_ppc.hpp"
825 #endif
826 #ifdef TARGET_OS_ARCH_bsd_x86
827 # include "os_bsd_x86.hpp"
828 #endif
829 #ifdef TARGET_OS_ARCH_bsd_zero
830 # include "os_bsd_zero.hpp"
831 #endif
832
833 #ifndef OS_NATIVE_THREAD_CREATION_FAILED_MSG
834 #define OS_NATIVE_THREAD_CREATION_FAILED_MSG "unable to create native thread: possibly out of memory or process/resource limits reached"
835 #endif
836
837 public:
838 #ifndef PLATFORM_PRINT_NATIVE_STACK
839 // No platform-specific code for printing the native stack.
840 static bool platform_print_native_stack(outputStream* st, void* context,
841 char *buf, int buf_size) {
842 return false;
843 }
844 #endif
845
846 // debugging support (mostly used by debug.cpp but also fatal error handler)
847 static bool find(address pc, outputStream* st = tty); // OS specific function to make sense out of an address
848
849 static bool dont_yield(); // when true, JVM_Yield() is nop
850 static void print_statistics();
851
852 // Thread priority helpers (implemented in OS-specific part)
853 static OSReturn set_native_priority(Thread* thread, int native_prio);
854 static OSReturn get_native_priority(const Thread* const thread, int* priority_ptr);
855 static int java_to_os_priority[CriticalPriority + 1];
856 // Hint to the underlying OS that a task switch would not be good.
857 // Void return because it's a hint and can fail.
858 static void hint_no_preempt();
859 static const char* native_thread_creation_failed_msg() {
860 return OS_NATIVE_THREAD_CREATION_FAILED_MSG;
861 }
862
863 // Used at creation if requested by the diagnostic flag PauseAtStartup.
864 // Causes the VM to wait until an external stimulus has been applied
865 // (for Unix, that stimulus is a signal, for Windows, an external
866 // ResumeThread call)
867 static void pause();
868
869 // Builds a platform dependent Agent_OnLoad_<libname> function name
870 // which is used to find statically linked in agents.
871 static char* build_agent_function_name(const char *sym, const char *cname,
872 bool is_absolute_path);
873
874 class SuspendedThreadTaskContext {
875 public:
876 SuspendedThreadTaskContext(Thread* thread, void *ucontext) : _thread(thread), _ucontext(ucontext) {}
877 Thread* thread() const { return _thread; }
878 void* ucontext() const { return _ucontext; }
879 private:
880 Thread* _thread;
881 void* _ucontext;
882 };
883
884 class SuspendedThreadTask {
885 public:
886 SuspendedThreadTask(Thread* thread) : _thread(thread), _done(false) {}
887 virtual ~SuspendedThreadTask() {}
888 void run();
889 bool is_done() { return _done; }
890 virtual void do_task(const SuspendedThreadTaskContext& context) = 0;
891 protected:
892 private:
893 void internal_do_task();
894 Thread* _thread;
895 bool _done;
896 };
897
898 #ifndef TARGET_OS_FAMILY_windows
899 // Suspend/resume support
900 // Protocol:
901 //
902 // a thread starts in SR_RUNNING
903 //
904 // SR_RUNNING can go to
905 // * SR_SUSPEND_REQUEST when the WatcherThread wants to suspend it
906 // SR_SUSPEND_REQUEST can go to
907 // * SR_RUNNING if WatcherThread decides it waited for SR_SUSPENDED too long (timeout)
908 // * SR_SUSPENDED if the stopped thread receives the signal and switches state
909 // SR_SUSPENDED can go to
910 // * SR_WAKEUP_REQUEST when the WatcherThread has done the work and wants to resume
911 // SR_WAKEUP_REQUEST can go to
912 // * SR_RUNNING when the stopped thread receives the signal
913 // * SR_WAKEUP_REQUEST on timeout (resend the signal and try again)
914 class SuspendResume {
915 public:
916 enum State {
917 SR_RUNNING,
918 SR_SUSPEND_REQUEST,
919 SR_SUSPENDED,
920 SR_WAKEUP_REQUEST
921 };
922
923 private:
924 volatile State _state;
925
926 private:
927 /* try to switch state from state "from" to state "to"
928 * returns the state set after the method is complete
929 */
930 State switch_state(State from, State to);
931
932 public:
933 SuspendResume() : _state(SR_RUNNING) { }
934
935 State state() const { return _state; }
936
937 State request_suspend() {
938 return switch_state(SR_RUNNING, SR_SUSPEND_REQUEST);
939 }
940
941 State cancel_suspend() {
942 return switch_state(SR_SUSPEND_REQUEST, SR_RUNNING);
943 }
944
945 State suspended() {
946 return switch_state(SR_SUSPEND_REQUEST, SR_SUSPENDED);
947 }
948
949 State request_wakeup() {
950 return switch_state(SR_SUSPENDED, SR_WAKEUP_REQUEST);
951 }
952
953 State running() {
954 return switch_state(SR_WAKEUP_REQUEST, SR_RUNNING);
955 }
956
957 bool is_running() const {
958 return _state == SR_RUNNING;
959 }
960
961 bool is_suspend_request() const {
962 return _state == SR_SUSPEND_REQUEST;
963 }
964
965 bool is_suspended() const {
966 return _state == SR_SUSPENDED;
967 }
968 };
969 #endif
970
971
972 protected:
973 static long _rand_seed; // seed for random number generator
974 static int _processor_count; // number of processors
975
976 static char* format_boot_path(const char* format_string,
977 const char* home,
978 int home_len,
979 char fileSep,
980 char pathSep);
981 static bool set_boot_path(char fileSep, char pathSep);
982 static char** split_path(const char* path, int* n);
983
984 };
985
986 // Note that "PAUSE" is almost always used with synchronization
987 // so arguably we should provide Atomic::SpinPause() instead
988 // of the global SpinPause() with C linkage.
989 // It'd also be eligible for inlining on many platforms.
990
991 extern "C" int SpinPause();
992
993 #endif // SHARE_VM_RUNTIME_OS_HPP