1 /*
2 * Copyright (c) 1997, 2010, 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 #endif
36 #ifdef TARGET_OS_FAMILY_solaris
37 # include "jvm_solaris.h"
38 #endif
39 #ifdef TARGET_OS_FAMILY_windows
40 # include "jvm_windows.h"
41 #endif
42
43 // os defines the interface to operating system; this includes traditional
44 // OS services (time, I/O) as well as other functionality with system-
45 // dependent code.
46
47 typedef void (*dll_func)(...);
48
49 class Thread;
50 class JavaThread;
51 class Event;
52 class DLL;
53 class FileHandle;
54 template<class E> class GrowableArray;
55
56 // %%%%% Moved ThreadState, START_FN, OSThread to new osThread.hpp. -- Rose
57
58 // Platform-independent error return values from OS functions
59 enum OSReturn {
60 OS_OK = 0, // Operation was successful
61 OS_ERR = -1, // Operation failed
62 OS_INTRPT = -2, // Operation was interrupted
63 OS_TIMEOUT = -3, // Operation timed out
64 OS_NOMEM = -5, // Operation failed for lack of memory
65 OS_NORESOURCE = -6 // Operation failed for lack of nonmemory resource
66 };
67
68 enum ThreadPriority { // JLS 20.20.1-3
69 NoPriority = -1, // Initial non-priority value
70 MinPriority = 1, // Minimum priority
71 NormPriority = 5, // Normal (non-daemon) priority
72 NearMaxPriority = 9, // High priority, used for VMThread
73 MaxPriority = 10 // Highest priority, used for WatcherThread
74 // ensures that VMThread doesn't starve profiler
75 };
76
77 // Typedef for structured exception handling support
78 typedef void (*java_call_t)(JavaValue* value, methodHandle* method, JavaCallArguments* args, Thread* thread);
79
80 class os: AllStatic {
81 public:
82 enum { page_sizes_max = 9 }; // Size of _page_sizes array (8 plus a sentinel)
83
84 private:
85 static OSThread* _starting_thread;
86 static address _polling_page;
87 static volatile int32_t * _mem_serialize_page;
88 static uintptr_t _serialize_page_mask;
89 public:
90 static size_t _page_sizes[page_sizes_max];
91
92 private:
93 static void init_page_sizes(size_t default_page_size) {
94 _page_sizes[0] = default_page_size;
95 _page_sizes[1] = 0; // sentinel
96 }
97
98 public:
99
100 static void init(void); // Called before command line parsing
101 static jint init_2(void); // Called after command line parsing
102 static void init_3(void); // Called at the end of vm init
103
104 // File names are case-insensitive on windows only
105 // Override me as needed
106 static int file_name_strcmp(const char* s1, const char* s2);
107
108 static bool getenv(const char* name, char* buffer, int len);
109 static bool have_special_privileges();
110
111 static jlong javaTimeMillis();
112 static jlong javaTimeNanos();
113 static void javaTimeNanos_info(jvmtiTimerInfo *info_ptr);
114 static void run_periodic_checks();
115
116
117 // Returns the elapsed time in seconds since the vm started.
118 static double elapsedTime();
119
120 // Returns real time in seconds since an arbitrary point
121 // in the past.
122 static bool getTimesSecs(double* process_real_time,
123 double* process_user_time,
124 double* process_system_time);
125
126 // Interface to the performance counter
127 static jlong elapsed_counter();
128 static jlong elapsed_frequency();
129
130 // The "virtual time" of a thread is the amount of time a thread has
131 // actually run. The first function indicates whether the OS supports
132 // this functionality for the current thread, and if so:
133 // * the second enables vtime tracking (if that is required).
134 // * the third tells whether vtime is enabled.
135 // * the fourth returns the elapsed virtual time for the current
136 // thread.
137 static bool supports_vtime();
138 static bool enable_vtime();
139 static bool vtime_enabled();
140 static double elapsedVTime();
141
142 // Return current local time in a string (YYYY-MM-DD HH:MM:SS).
143 // It is MT safe, but not async-safe, as reading time zone
144 // information may require a lock on some platforms.
145 static char* local_time_string(char *buf, size_t buflen);
146 static struct tm* localtime_pd (const time_t* clock, struct tm* res);
147 // Fill in buffer with current local time as an ISO-8601 string.
148 // E.g., YYYY-MM-DDThh:mm:ss.mmm+zzzz.
149 // Returns buffer, or NULL if it failed.
150 static char* iso8601_time(char* buffer, size_t buffer_length);
151
152 // Interface for detecting multiprocessor system
153 static inline bool is_MP() {
154 assert(_processor_count > 0, "invalid processor count");
155 return _processor_count > 1;
156 }
157 static julong available_memory();
158 static julong physical_memory();
159 static julong allocatable_physical_memory(julong size);
160 static bool is_server_class_machine();
161
162 // number of CPUs
163 static int processor_count() {
164 return _processor_count;
165 }
166 static void set_processor_count(int count) { _processor_count = count; }
167
168 // Returns the number of CPUs this process is currently allowed to run on.
169 // Note that on some OSes this can change dynamically.
170 static int active_processor_count();
171
172 // Bind processes to processors.
173 // This is a two step procedure:
174 // first you generate a distribution of processes to processors,
175 // then you bind processes according to that distribution.
176 // Compute a distribution for number of processes to processors.
177 // Stores the processor id's into the distribution array argument.
178 // Returns true if it worked, false if it didn't.
179 static bool distribute_processes(uint length, uint* distribution);
180 // Binds the current process to a processor.
181 // Returns true if it worked, false if it didn't.
182 static bool bind_to_processor(uint processor_id);
183
184 // Interface for stack banging (predetect possible stack overflow for
185 // exception processing) There are guard pages, and above that shadow
186 // pages for stack overflow checking.
187 static bool uses_stack_guard_pages();
188 static bool allocate_stack_guard_pages();
189 static void bang_stack_shadow_pages();
190 static bool stack_shadow_pages_available(Thread *thread, methodHandle method);
191
192 // OS interface to Virtual Memory
193
194 // Return the default page size.
195 static int vm_page_size();
196
197 // Return the page size to use for a region of memory. The min_pages argument
198 // is a hint intended to limit fragmentation; it says the returned page size
199 // should be <= region_max_size / min_pages. Because min_pages is a hint,
200 // this routine may return a size larger than region_max_size / min_pages.
201 //
202 // The current implementation ignores min_pages if a larger page size is an
203 // exact multiple of both region_min_size and region_max_size. This allows
204 // larger pages to be used when doing so would not cause fragmentation; in
205 // particular, a single page can be used when region_min_size ==
206 // region_max_size == a supported page size.
207 static size_t page_size_for_region(size_t region_min_size,
208 size_t region_max_size,
209 uint min_pages);
210
211 // Method for tracing page sizes returned by the above method; enabled by
212 // TracePageSizes. The region_{min,max}_size parameters should be the values
213 // passed to page_size_for_region() and page_size should be the result of that
214 // call. The (optional) base and size parameters should come from the
215 // ReservedSpace base() and size() methods.
216 static void trace_page_sizes(const char* str, const size_t region_min_size,
217 const size_t region_max_size,
218 const size_t page_size,
219 const char* base = NULL,
220 const size_t size = 0) PRODUCT_RETURN;
221
222 static int vm_allocation_granularity();
223 static char* reserve_memory(size_t bytes, char* addr = 0,
224 size_t alignment_hint = 0);
225 static char* attempt_reserve_memory_at(size_t bytes, char* addr);
226 static void split_reserved_memory(char *base, size_t size,
227 size_t split, bool realloc);
228 static bool commit_memory(char* addr, size_t bytes,
229 bool executable = false);
230 static bool commit_memory(char* addr, size_t size, size_t alignment_hint,
231 bool executable = false);
232 static bool uncommit_memory(char* addr, size_t bytes);
233 static bool release_memory(char* addr, size_t bytes);
234
235 enum ProtType { MEM_PROT_NONE, MEM_PROT_READ, MEM_PROT_RW, MEM_PROT_RWX };
236 static bool protect_memory(char* addr, size_t bytes, ProtType prot,
237 bool is_committed = true);
238
239 static bool guard_memory(char* addr, size_t bytes);
240 static bool unguard_memory(char* addr, size_t bytes);
241 static bool create_stack_guard_pages(char* addr, size_t bytes);
242 static bool remove_stack_guard_pages(char* addr, size_t bytes);
243
244 static char* map_memory(int fd, const char* file_name, size_t file_offset,
245 char *addr, size_t bytes, bool read_only = false,
246 bool allow_exec = false);
247 static char* remap_memory(int fd, const char* file_name, size_t file_offset,
248 char *addr, size_t bytes, bool read_only,
249 bool allow_exec);
250 static bool unmap_memory(char *addr, size_t bytes);
251 static void free_memory(char *addr, size_t bytes);
252 static void realign_memory(char *addr, size_t bytes, size_t alignment_hint);
253
254 // NUMA-specific interface
255 static bool numa_has_static_binding();
256 static bool numa_has_group_homing();
257 static void numa_make_local(char *addr, size_t bytes, int lgrp_hint);
258 static void numa_make_global(char *addr, size_t bytes);
259 static size_t numa_get_groups_num();
260 static size_t numa_get_leaf_groups(int *ids, size_t size);
261 static bool numa_topology_changed();
262 static int numa_get_group_id();
263
264 // Page manipulation
265 struct page_info {
266 size_t size;
267 int lgrp_id;
268 };
269 static bool get_page_info(char *start, page_info* info);
270 static char* scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found);
271
272 static char* non_memory_address_word();
273 // reserve, commit and pin the entire memory region
274 static char* reserve_memory_special(size_t size, char* addr = NULL,
275 bool executable = false);
276 static bool release_memory_special(char* addr, size_t bytes);
277 static bool large_page_init();
278 static size_t large_page_size();
279 static bool can_commit_large_page_memory();
280 static bool can_execute_large_page_memory();
281
282 // OS interface to polling page
283 static address get_polling_page() { return _polling_page; }
284 static void set_polling_page(address page) { _polling_page = page; }
285 static bool is_poll_address(address addr) { return addr >= _polling_page && addr < (_polling_page + os::vm_page_size()); }
286 static void make_polling_page_unreadable();
287 static void make_polling_page_readable();
288
289 // Routines used to serialize the thread state without using membars
290 static void serialize_thread_states();
291
292 // Since we write to the serialize page from every thread, we
293 // want stores to be on unique cache lines whenever possible
294 // in order to minimize CPU cross talk. We pre-compute the
295 // amount to shift the thread* to make this offset unique to
296 // each thread.
297 static int get_serialize_page_shift_count() {
298 return SerializePageShiftCount;
299 }
300
301 static void set_serialize_page_mask(uintptr_t mask) {
302 _serialize_page_mask = mask;
303 }
304
305 static unsigned int get_serialize_page_mask() {
306 return _serialize_page_mask;
307 }
308
309 static void set_memory_serialize_page(address page);
310
311 static address get_memory_serialize_page() {
312 return (address)_mem_serialize_page;
313 }
314
315 static inline void write_memory_serialize_page(JavaThread *thread) {
316 uintptr_t page_offset = ((uintptr_t)thread >>
317 get_serialize_page_shift_count()) &
318 get_serialize_page_mask();
319 *(volatile int32_t *)((uintptr_t)_mem_serialize_page+page_offset) = 1;
320 }
321
322 static bool is_memory_serialize_page(JavaThread *thread, address addr) {
323 if (UseMembar) return false;
324 // Previously this function calculated the exact address of this
325 // thread's serialize page, and checked if the faulting address
326 // was equal. However, some platforms mask off faulting addresses
327 // to the page size, so now we just check that the address is
328 // within the page. This makes the thread argument unnecessary,
329 // but we retain the NULL check to preserve existing behaviour.
330 if (thread == NULL) return false;
331 address page = (address) _mem_serialize_page;
332 return addr >= page && addr < (page + os::vm_page_size());
333 }
334
335 static void block_on_serialize_page_trap();
336
337 // threads
338
339 enum ThreadType {
340 vm_thread,
341 cgc_thread, // Concurrent GC thread
342 pgc_thread, // Parallel GC thread
343 java_thread,
344 compiler_thread,
345 watcher_thread,
346 os_thread
347 };
348
349 static bool create_thread(Thread* thread,
350 ThreadType thr_type,
351 size_t stack_size = 0);
352 static bool create_main_thread(JavaThread* thread);
353 static bool create_attached_thread(JavaThread* thread);
354 static void pd_start_thread(Thread* thread);
355 static void start_thread(Thread* thread);
356
357 static void initialize_thread();
358 static void free_thread(OSThread* osthread);
359
360 // thread id on Linux/64bit is 64bit, on Windows and Solaris, it's 32bit
361 static intx current_thread_id();
362 static int current_process_id();
363 // hpi::read for calls from non native state
364 // For performance, hpi::read is only callable from _thread_in_native
365 static size_t read(int fd, void *buf, unsigned int nBytes);
366 static int sleep(Thread* thread, jlong ms, bool interruptable);
367 static int naked_sleep();
368 static void infinite_sleep(); // never returns, use with CAUTION
369 static void yield(); // Yields to all threads with same priority
370 enum YieldResult {
371 YIELD_SWITCHED = 1, // caller descheduled, other ready threads exist & ran
372 YIELD_NONEREADY = 0, // No other runnable/ready threads.
373 // platform-specific yield return immediately
374 YIELD_UNKNOWN = -1 // Unknown: platform doesn't support _SWITCHED or _NONEREADY
375 // YIELD_SWITCHED and YIELD_NONREADY imply the platform supports a "strong"
376 // yield that can be used in lieu of blocking.
377 } ;
378 static YieldResult NakedYield () ;
379 static void yield_all(int attempts = 0); // Yields to all other threads including lower priority
380 static void loop_breaker(int attempts); // called from within tight loops to possibly influence time-sharing
381 static OSReturn set_priority(Thread* thread, ThreadPriority priority);
382 static OSReturn get_priority(const Thread* const thread, ThreadPriority& priority);
383
384 static void interrupt(Thread* thread);
385 static bool is_interrupted(Thread* thread, bool clear_interrupted);
386
387 static int pd_self_suspend_thread(Thread* thread);
388
389 static ExtendedPC fetch_frame_from_context(void* ucVoid, intptr_t** sp, intptr_t** fp);
390 static frame fetch_frame_from_context(void* ucVoid);
391
392 static ExtendedPC get_thread_pc(Thread *thread);
393 static void breakpoint();
394
395 static address current_stack_pointer();
396 static address current_stack_base();
397 static size_t current_stack_size();
398
399 static int message_box(const char* title, const char* message);
400 static char* do_you_want_to_debug(const char* message);
401
402 // run cmd in a separate process and return its exit code; or -1 on failures
403 static int fork_and_exec(char *cmd);
404
405 // Set file to send error reports.
406 static void set_error_file(const char *logfile);
407
408 // os::exit() is merged with vm_exit()
409 // static void exit(int num);
410
411 // Terminate the VM, but don't exit the process
412 static void shutdown();
413
414 // Terminate with an error. Default is to generate a core file on platforms
415 // that support such things. This calls shutdown() and then aborts.
416 static void abort(bool dump_core = true);
417
418 // Die immediately, no exit hook, no abort hook, no cleanup.
419 static void die();
420
421 // Reading directories.
422 static DIR* opendir(const char* dirname);
423 static int readdir_buf_size(const char *path);
424 static struct dirent* readdir(DIR* dirp, dirent* dbuf);
425 static int closedir(DIR* dirp);
426
427 // Dynamic library extension
428 static const char* dll_file_extension();
429
430 static const char* get_temp_directory();
431 static const char* get_current_directory(char *buf, int buflen);
432
433 // Builds a platform-specific full library path given a ld path and lib name
434 static void dll_build_name(char* buffer, size_t size,
435 const char* pathname, const char* fname);
436
437 // Symbol lookup, find nearest function name; basically it implements
438 // dladdr() for all platforms. Name of the nearest function is copied
439 // to buf. Distance from its base address is returned as offset.
440 // If function name is not found, buf[0] is set to '\0' and offset is
441 // set to -1.
442 static bool dll_address_to_function_name(address addr, char* buf,
443 int buflen, int* offset);
444
445 // Locate DLL/DSO. On success, full path of the library is copied to
446 // buf, and offset is set to be the distance between addr and the
447 // library's base address. On failure, buf[0] is set to '\0' and
448 // offset is set to -1.
449 static bool dll_address_to_library_name(address addr, char* buf,
450 int buflen, int* offset);
451
452 // Find out whether the pc is in the static code for jvm.dll/libjvm.so.
453 static bool address_is_in_vm(address addr);
454
455 // Loads .dll/.so and
456 // in case of error it checks if .dll/.so was built for the
457 // same architecture as Hotspot is running on
458 static void* dll_load(const char *name, char *ebuf, int ebuflen);
459
460 // lookup symbol in a shared library
461 static void* dll_lookup(void* handle, const char* name);
462
463 // Print out system information; they are called by fatal error handler.
464 // Output format may be different on different platforms.
465 static void print_os_info(outputStream* st);
466 static void print_cpu_info(outputStream* st);
467 static void print_memory_info(outputStream* st);
468 static void print_dll_info(outputStream* st);
469 static void print_environment_variables(outputStream* st, const char** env_list, char* buffer, int len);
470 static void print_context(outputStream* st, void* context);
471 static void print_siginfo(outputStream* st, void* siginfo);
472 static void print_signal_handlers(outputStream* st, char* buf, size_t buflen);
473 static void print_date_and_time(outputStream* st);
474
475 static void print_location(outputStream* st, intptr_t x, bool print_pc = false);
476
477 // The following two functions are used by fatal error handler to trace
478 // native (C) frames. They are not part of frame.hpp/frame.cpp because
479 // frame.hpp/cpp assume thread is JavaThread, and also because different
480 // OS/compiler may have different convention or provide different API to
481 // walk C frames.
482 //
483 // We don't attempt to become a debugger, so we only follow frames if that
484 // does not require a lookup in the unwind table, which is part of the binary
485 // file but may be unsafe to read after a fatal error. So on x86, we can
486 // only walk stack if %ebp is used as frame pointer; on ia64, it's not
487 // possible to walk C stack without having the unwind table.
488 static bool is_first_C_frame(frame *fr);
489 static frame get_sender_for_C_frame(frame *fr);
490
491 // return current frame. pc() and sp() are set to NULL on failure.
492 static frame current_frame();
493
494 static void print_hex_dump(outputStream* st, address start, address end, int unitsize);
495
496 // returns a string to describe the exception/signal;
497 // returns NULL if exception_code is not an OS exception/signal.
498 static const char* exception_name(int exception_code, char* buf, size_t buflen);
499
500 // Returns native Java library, loads if necessary
501 static void* native_java_library();
502
503 // Fills in path to jvm.dll/libjvm.so (this info used to find hpi).
504 static void jvm_path(char *buf, jint buflen);
505
506 // Returns true if we are running in a headless jre.
507 static bool is_headless_jre();
508
509 // JNI names
510 static void print_jni_name_prefix_on(outputStream* st, int args_size);
511 static void print_jni_name_suffix_on(outputStream* st, int args_size);
512
513 // File conventions
514 static const char* file_separator();
515 static const char* line_separator();
516 static const char* path_separator();
517
518 // Init os specific system properties values
519 static void init_system_properties_values();
520
521 // IO operations, non-JVM_ version.
522 static int stat(const char* path, struct stat* sbuf);
523 static bool dir_is_empty(const char* path);
524
525 // IO operations on binary files
526 static int create_binary_file(const char* path, bool rewrite_existing);
527 static jlong current_file_offset(int fd);
528 static jlong seek_to_file_offset(int fd, jlong offset);
529
530 // Thread Local Storage
531 static int allocate_thread_local_storage();
532 static void thread_local_storage_at_put(int index, void* value);
533 static void* thread_local_storage_at(int index);
534 static void free_thread_local_storage(int index);
535
536 // General allocation (must be MT-safe)
537 static void* malloc (size_t size);
538 static void* realloc (void *memblock, size_t size);
539 static void free (void *memblock);
540 static bool check_heap(bool force = false); // verify C heap integrity
541 static char* strdup(const char *); // Like strdup
542
543 #ifndef PRODUCT
544 static int num_mallocs; // # of calls to malloc/realloc
545 static size_t alloc_bytes; // # of bytes allocated
546 static int num_frees; // # of calls to free
547 #endif
548
549 // Printing 64 bit integers
550 static const char* jlong_format_specifier();
551 static const char* julong_format_specifier();
552
553 // Support for signals (see JVM_RaiseSignal, JVM_RegisterSignal)
554 static void signal_init();
555 static void signal_init_pd();
556 static void signal_notify(int signal_number);
557 static void* signal(int signal_number, void* handler);
558 static void signal_raise(int signal_number);
559 static int signal_wait();
560 static int signal_lookup();
561 static void* user_handler();
562 static void terminate_signal_thread();
563 static int sigexitnum_pd();
564
565 // random number generation
566 static long random(); // return 32bit pseudorandom number
567 static void init_random(long initval); // initialize random sequence
568
569 // Structured OS Exception support
570 static void os_exception_wrapper(java_call_t f, JavaValue* value, methodHandle* method, JavaCallArguments* args, Thread* thread);
571
572 // JVMTI & JVM monitoring and management support
573 // The thread_cpu_time() and current_thread_cpu_time() are only
574 // supported if is_thread_cpu_time_supported() returns true.
575 // They are not supported on Solaris T1.
576
577 // Thread CPU Time - return the fast estimate on a platform
578 // On Solaris - call gethrvtime (fast) - user time only
579 // On Linux - fast clock_gettime where available - user+sys
580 // - otherwise: very slow /proc fs - user+sys
581 // On Windows - GetThreadTimes - user+sys
582 static jlong current_thread_cpu_time();
583 static jlong thread_cpu_time(Thread* t);
584
585 // Thread CPU Time with user_sys_cpu_time parameter.
586 //
587 // If user_sys_cpu_time is true, user+sys time is returned.
588 // Otherwise, only user time is returned
589 static jlong current_thread_cpu_time(bool user_sys_cpu_time);
590 static jlong thread_cpu_time(Thread* t, bool user_sys_cpu_time);
591
592 // Return a bunch of info about the timers.
593 // Note that the returned info for these two functions may be different
594 // on some platforms
595 static void current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr);
596 static void thread_cpu_time_info(jvmtiTimerInfo *info_ptr);
597
598 static bool is_thread_cpu_time_supported();
599
600 // System loadavg support. Returns -1 if load average cannot be obtained.
601 static int loadavg(double loadavg[], int nelem);
602
603 // Hook for os specific jvm options that we don't want to abort on seeing
604 static bool obsolete_option(const JavaVMOption *option);
605
606 // Platform dependent stuff
607 #ifdef TARGET_OS_FAMILY_linux
608 # include "os_linux.hpp"
609 #endif
610 #ifdef TARGET_OS_FAMILY_solaris
611 # include "os_solaris.hpp"
612 #endif
613 #ifdef TARGET_OS_FAMILY_windows
614 # include "os_windows.hpp"
615 #endif
616 #ifdef TARGET_OS_ARCH_linux_x86
617 # include "os_linux_x86.hpp"
618 #endif
619 #ifdef TARGET_OS_ARCH_linux_sparc
620 # include "os_linux_sparc.hpp"
621 #endif
622 #ifdef TARGET_OS_ARCH_linux_zero
623 # include "os_linux_zero.hpp"
624 #endif
625 #ifdef TARGET_OS_ARCH_solaris_x86
626 # include "os_solaris_x86.hpp"
627 #endif
628 #ifdef TARGET_OS_ARCH_solaris_sparc
629 # include "os_solaris_sparc.hpp"
630 #endif
631 #ifdef TARGET_OS_ARCH_windows_x86
632 # include "os_windows_x86.hpp"
633 #endif
634
635
636 // debugging support (mostly used by debug.cpp but also fatal error handler)
637 static bool find(address pc, outputStream* st = tty); // OS specific function to make sense out of an address
638
639 static bool dont_yield(); // when true, JVM_Yield() is nop
640 static void print_statistics();
641
642 // Thread priority helpers (implemented in OS-specific part)
643 static OSReturn set_native_priority(Thread* thread, int native_prio);
644 static OSReturn get_native_priority(const Thread* const thread, int* priority_ptr);
645 static int java_to_os_priority[MaxPriority + 1];
646 // Hint to the underlying OS that a task switch would not be good.
647 // Void return because it's a hint and can fail.
648 static void hint_no_preempt();
649
650 // Used at creation if requested by the diagnostic flag PauseAtStartup.
651 // Causes the VM to wait until an external stimulus has been applied
652 // (for Unix, that stimulus is a signal, for Windows, an external
653 // ResumeThread call)
654 static void pause();
655
656 protected:
657 static long _rand_seed; // seed for random number generator
658 static int _processor_count; // number of processors
659
660 static char* format_boot_path(const char* format_string,
661 const char* home,
662 int home_len,
663 char fileSep,
664 char pathSep);
665 static bool set_boot_path(char fileSep, char pathSep);
666 static char** split_path(const char* path, int* n);
667 };
668
669 // Note that "PAUSE" is almost always used with synchronization
670 // so arguably we should provide Atomic::SpinPause() instead
671 // of the global SpinPause() with C linkage.
672 // It'd also be eligible for inlining on many platforms.
673
674 extern "C" int SpinPause () ;
675 extern "C" int SafeFetch32 (int * adr, int errValue) ;
676 extern "C" intptr_t SafeFetchN (intptr_t * adr, intptr_t errValue) ;
677
678 #endif // SHARE_VM_RUNTIME_OS_HPP