Thu, 19 Sep 2013 09:26:08 +0200
Merge
1 /*
2 * Copyright (c) 1997, 2013, 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 */
25 #ifndef SHARE_VM_RUNTIME_OS_HPP
26 #define SHARE_VM_RUNTIME_OS_HPP
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_bsd
45 # include "jvm_bsd.h"
46 # include <setjmp.h>
47 #endif
49 class AgentLibrary;
51 // os defines the interface to operating system; this includes traditional
52 // OS services (time, I/O) as well as other functionality with system-
53 // dependent code.
55 typedef void (*dll_func)(...);
57 class Thread;
58 class JavaThread;
59 class Event;
60 class DLL;
61 class FileHandle;
62 template<class E> class GrowableArray;
64 // %%%%% Moved ThreadState, START_FN, OSThread to new osThread.hpp. -- Rose
66 // Platform-independent error return values from OS functions
67 enum OSReturn {
68 OS_OK = 0, // Operation was successful
69 OS_ERR = -1, // Operation failed
70 OS_INTRPT = -2, // Operation was interrupted
71 OS_TIMEOUT = -3, // Operation timed out
72 OS_NOMEM = -5, // Operation failed for lack of memory
73 OS_NORESOURCE = -6 // Operation failed for lack of nonmemory resource
74 };
76 enum ThreadPriority { // JLS 20.20.1-3
77 NoPriority = -1, // Initial non-priority value
78 MinPriority = 1, // Minimum priority
79 NormPriority = 5, // Normal (non-daemon) priority
80 NearMaxPriority = 9, // High priority, used for VMThread
81 MaxPriority = 10, // Highest priority, used for WatcherThread
82 // ensures that VMThread doesn't starve profiler
83 CriticalPriority = 11 // Critical thread priority
84 };
86 // Executable parameter flag for os::commit_memory() and
87 // os::commit_memory_or_exit().
88 const bool ExecMem = true;
90 // Typedef for structured exception handling support
91 typedef void (*java_call_t)(JavaValue* value, methodHandle* method, JavaCallArguments* args, Thread* thread);
93 class os: AllStatic {
94 public:
95 enum { page_sizes_max = 9 }; // Size of _page_sizes array (8 plus a sentinel)
97 private:
98 static OSThread* _starting_thread;
99 static address _polling_page;
100 static volatile int32_t * _mem_serialize_page;
101 static uintptr_t _serialize_page_mask;
102 public:
103 static size_t _page_sizes[page_sizes_max];
105 private:
106 static void init_page_sizes(size_t default_page_size) {
107 _page_sizes[0] = default_page_size;
108 _page_sizes[1] = 0; // sentinel
109 }
111 static char* pd_reserve_memory(size_t bytes, char* addr = 0,
112 size_t alignment_hint = 0);
113 static char* pd_attempt_reserve_memory_at(size_t bytes, char* addr);
114 static void pd_split_reserved_memory(char *base, size_t size,
115 size_t split, bool realloc);
116 static bool pd_commit_memory(char* addr, size_t bytes, bool executable);
117 static bool pd_commit_memory(char* addr, size_t size, size_t alignment_hint,
118 bool executable);
119 // Same as pd_commit_memory() that either succeeds or calls
120 // vm_exit_out_of_memory() with the specified mesg.
121 static void pd_commit_memory_or_exit(char* addr, size_t bytes,
122 bool executable, const char* mesg);
123 static void pd_commit_memory_or_exit(char* addr, size_t size,
124 size_t alignment_hint,
125 bool executable, const char* mesg);
126 static bool pd_uncommit_memory(char* addr, size_t bytes);
127 static bool pd_release_memory(char* addr, size_t bytes);
129 static char* pd_map_memory(int fd, const char* file_name, size_t file_offset,
130 char *addr, size_t bytes, bool read_only = false,
131 bool allow_exec = false);
132 static char* pd_remap_memory(int fd, const char* file_name, size_t file_offset,
133 char *addr, size_t bytes, bool read_only,
134 bool allow_exec);
135 static bool pd_unmap_memory(char *addr, size_t bytes);
136 static void pd_free_memory(char *addr, size_t bytes, size_t alignment_hint);
137 static void pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint);
140 public:
141 static void init(void); // Called before command line parsing
142 static void init_before_ergo(void); // Called after command line parsing
143 // before VM ergonomics processing.
144 static jint init_2(void); // Called after command line parsing
145 // and VM ergonomics processing
146 static void init_globals(void) { // Called from init_globals() in init.cpp
147 init_globals_ext();
148 }
149 static void init_3(void); // Called at the end of vm init
151 // File names are case-insensitive on windows only
152 // Override me as needed
153 static int file_name_strcmp(const char* s1, const char* s2);
155 static bool getenv(const char* name, char* buffer, int len);
156 static bool have_special_privileges();
158 static jlong javaTimeMillis();
159 static jlong javaTimeNanos();
160 static void javaTimeNanos_info(jvmtiTimerInfo *info_ptr);
161 static void run_periodic_checks();
164 // Returns the elapsed time in seconds since the vm started.
165 static double elapsedTime();
167 // Returns real time in seconds since an arbitrary point
168 // in the past.
169 static bool getTimesSecs(double* process_real_time,
170 double* process_user_time,
171 double* process_system_time);
173 // Interface to the performance counter
174 static jlong elapsed_counter();
175 static jlong elapsed_frequency();
177 // The "virtual time" of a thread is the amount of time a thread has
178 // actually run. The first function indicates whether the OS supports
179 // this functionality for the current thread, and if so:
180 // * the second enables vtime tracking (if that is required).
181 // * the third tells whether vtime is enabled.
182 // * the fourth returns the elapsed virtual time for the current
183 // thread.
184 static bool supports_vtime();
185 static bool enable_vtime();
186 static bool vtime_enabled();
187 static double elapsedVTime();
189 // Return current local time in a string (YYYY-MM-DD HH:MM:SS).
190 // It is MT safe, but not async-safe, as reading time zone
191 // information may require a lock on some platforms.
192 static char* local_time_string(char *buf, size_t buflen);
193 static struct tm* localtime_pd (const time_t* clock, struct tm* res);
194 // Fill in buffer with current local time as an ISO-8601 string.
195 // E.g., YYYY-MM-DDThh:mm:ss.mmm+zzzz.
196 // Returns buffer, or NULL if it failed.
197 static char* iso8601_time(char* buffer, size_t buffer_length);
199 // Interface for detecting multiprocessor system
200 static inline bool is_MP() {
201 assert(_processor_count > 0, "invalid processor count");
202 return _processor_count > 1 || AssumeMP;
203 }
204 static julong available_memory();
205 static julong physical_memory();
206 static bool has_allocatable_memory_limit(julong* limit);
207 static bool is_server_class_machine();
209 // number of CPUs
210 static int processor_count() {
211 return _processor_count;
212 }
213 static void set_processor_count(int count) { _processor_count = count; }
215 // Returns the number of CPUs this process is currently allowed to run on.
216 // Note that on some OSes this can change dynamically.
217 static int active_processor_count();
219 // Bind processes to processors.
220 // This is a two step procedure:
221 // first you generate a distribution of processes to processors,
222 // then you bind processes according to that distribution.
223 // Compute a distribution for number of processes to processors.
224 // Stores the processor id's into the distribution array argument.
225 // Returns true if it worked, false if it didn't.
226 static bool distribute_processes(uint length, uint* distribution);
227 // Binds the current process to a processor.
228 // Returns true if it worked, false if it didn't.
229 static bool bind_to_processor(uint processor_id);
231 // Give a name to the current thread.
232 static void set_native_thread_name(const char *name);
234 // Interface for stack banging (predetect possible stack overflow for
235 // exception processing) There are guard pages, and above that shadow
236 // pages for stack overflow checking.
237 static bool uses_stack_guard_pages();
238 static bool allocate_stack_guard_pages();
239 static void bang_stack_shadow_pages();
240 static bool stack_shadow_pages_available(Thread *thread, methodHandle method);
242 // OS interface to Virtual Memory
244 // Return the default page size.
245 static int vm_page_size();
247 // Return the page size to use for a region of memory. The min_pages argument
248 // is a hint intended to limit fragmentation; it says the returned page size
249 // should be <= region_max_size / min_pages. Because min_pages is a hint,
250 // this routine may return a size larger than region_max_size / min_pages.
251 //
252 // The current implementation ignores min_pages if a larger page size is an
253 // exact multiple of both region_min_size and region_max_size. This allows
254 // larger pages to be used when doing so would not cause fragmentation; in
255 // particular, a single page can be used when region_min_size ==
256 // region_max_size == a supported page size.
257 static size_t page_size_for_region(size_t region_min_size,
258 size_t region_max_size,
259 uint min_pages);
260 // Return the largest page size that can be used
261 static size_t max_page_size() {
262 // The _page_sizes array is sorted in descending order.
263 return _page_sizes[0];
264 }
266 // Methods for tracing page sizes returned by the above method; enabled by
267 // TracePageSizes. The region_{min,max}_size parameters should be the values
268 // passed to page_size_for_region() and page_size should be the result of that
269 // call. The (optional) base and size parameters should come from the
270 // ReservedSpace base() and size() methods.
271 static void trace_page_sizes(const char* str, const size_t* page_sizes,
272 int count) PRODUCT_RETURN;
273 static void trace_page_sizes(const char* str, const size_t region_min_size,
274 const size_t region_max_size,
275 const size_t page_size,
276 const char* base = NULL,
277 const size_t size = 0) PRODUCT_RETURN;
279 static int vm_allocation_granularity();
280 static char* reserve_memory(size_t bytes, char* addr = 0,
281 size_t alignment_hint = 0);
282 static char* reserve_memory(size_t bytes, char* addr,
283 size_t alignment_hint, MEMFLAGS flags);
284 static char* reserve_memory_aligned(size_t size, size_t alignment);
285 static char* attempt_reserve_memory_at(size_t bytes, char* addr);
286 static void split_reserved_memory(char *base, size_t size,
287 size_t split, bool realloc);
288 static bool commit_memory(char* addr, size_t bytes, bool executable);
289 static bool commit_memory(char* addr, size_t size, size_t alignment_hint,
290 bool executable);
291 // Same as commit_memory() that either succeeds or calls
292 // vm_exit_out_of_memory() with the specified mesg.
293 static void commit_memory_or_exit(char* addr, size_t bytes,
294 bool executable, const char* mesg);
295 static void commit_memory_or_exit(char* addr, size_t size,
296 size_t alignment_hint,
297 bool executable, const char* mesg);
298 static bool uncommit_memory(char* addr, size_t bytes);
299 static bool release_memory(char* addr, size_t bytes);
301 enum ProtType { MEM_PROT_NONE, MEM_PROT_READ, MEM_PROT_RW, MEM_PROT_RWX };
302 static bool protect_memory(char* addr, size_t bytes, ProtType prot,
303 bool is_committed = true);
305 static bool guard_memory(char* addr, size_t bytes);
306 static bool unguard_memory(char* addr, size_t bytes);
307 static bool create_stack_guard_pages(char* addr, size_t bytes);
308 static bool pd_create_stack_guard_pages(char* addr, size_t bytes);
309 static bool remove_stack_guard_pages(char* addr, size_t bytes);
311 static char* map_memory(int fd, const char* file_name, size_t file_offset,
312 char *addr, size_t bytes, bool read_only = false,
313 bool allow_exec = false);
314 static char* remap_memory(int fd, const char* file_name, size_t file_offset,
315 char *addr, size_t bytes, bool read_only,
316 bool allow_exec);
317 static bool unmap_memory(char *addr, size_t bytes);
318 static void free_memory(char *addr, size_t bytes, size_t alignment_hint);
319 static void realign_memory(char *addr, size_t bytes, size_t alignment_hint);
321 // NUMA-specific interface
322 static bool numa_has_static_binding();
323 static bool numa_has_group_homing();
324 static void numa_make_local(char *addr, size_t bytes, int lgrp_hint);
325 static void numa_make_global(char *addr, size_t bytes);
326 static size_t numa_get_groups_num();
327 static size_t numa_get_leaf_groups(int *ids, size_t size);
328 static bool numa_topology_changed();
329 static int numa_get_group_id();
331 // Page manipulation
332 struct page_info {
333 size_t size;
334 int lgrp_id;
335 };
336 static bool get_page_info(char *start, page_info* info);
337 static char* scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found);
339 static char* non_memory_address_word();
340 // reserve, commit and pin the entire memory region
341 static char* reserve_memory_special(size_t size, size_t alignment,
342 char* addr, bool executable);
343 static bool release_memory_special(char* addr, size_t bytes);
344 static void large_page_init();
345 static size_t large_page_size();
346 static bool can_commit_large_page_memory();
347 static bool can_execute_large_page_memory();
349 // OS interface to polling page
350 static address get_polling_page() { return _polling_page; }
351 static void set_polling_page(address page) { _polling_page = page; }
352 static bool is_poll_address(address addr) { return addr >= _polling_page && addr < (_polling_page + os::vm_page_size()); }
353 static void make_polling_page_unreadable();
354 static void make_polling_page_readable();
356 // Routines used to serialize the thread state without using membars
357 static void serialize_thread_states();
359 // Since we write to the serialize page from every thread, we
360 // want stores to be on unique cache lines whenever possible
361 // in order to minimize CPU cross talk. We pre-compute the
362 // amount to shift the thread* to make this offset unique to
363 // each thread.
364 static int get_serialize_page_shift_count() {
365 return SerializePageShiftCount;
366 }
368 static void set_serialize_page_mask(uintptr_t mask) {
369 _serialize_page_mask = mask;
370 }
372 static unsigned int get_serialize_page_mask() {
373 return _serialize_page_mask;
374 }
376 static void set_memory_serialize_page(address page);
378 static address get_memory_serialize_page() {
379 return (address)_mem_serialize_page;
380 }
382 static inline void write_memory_serialize_page(JavaThread *thread) {
383 uintptr_t page_offset = ((uintptr_t)thread >>
384 get_serialize_page_shift_count()) &
385 get_serialize_page_mask();
386 *(volatile int32_t *)((uintptr_t)_mem_serialize_page+page_offset) = 1;
387 }
389 static bool is_memory_serialize_page(JavaThread *thread, address addr) {
390 if (UseMembar) return false;
391 // Previously this function calculated the exact address of this
392 // thread's serialize page, and checked if the faulting address
393 // was equal. However, some platforms mask off faulting addresses
394 // to the page size, so now we just check that the address is
395 // within the page. This makes the thread argument unnecessary,
396 // but we retain the NULL check to preserve existing behaviour.
397 if (thread == NULL) return false;
398 address page = (address) _mem_serialize_page;
399 return addr >= page && addr < (page + os::vm_page_size());
400 }
402 static void block_on_serialize_page_trap();
404 // threads
406 enum ThreadType {
407 vm_thread,
408 cgc_thread, // Concurrent GC thread
409 pgc_thread, // Parallel GC thread
410 java_thread,
411 compiler_thread,
412 watcher_thread,
413 os_thread
414 };
416 static bool create_thread(Thread* thread,
417 ThreadType thr_type,
418 size_t stack_size = 0);
419 static bool create_main_thread(JavaThread* thread);
420 static bool create_attached_thread(JavaThread* thread);
421 static void pd_start_thread(Thread* thread);
422 static void start_thread(Thread* thread);
424 static void initialize_thread(Thread* thr);
425 static void free_thread(OSThread* osthread);
427 // thread id on Linux/64bit is 64bit, on Windows and Solaris, it's 32bit
428 static intx current_thread_id();
429 static int current_process_id();
430 static int sleep(Thread* thread, jlong ms, bool interruptable);
431 static int naked_sleep();
432 static void infinite_sleep(); // never returns, use with CAUTION
433 static void yield(); // Yields to all threads with same priority
434 enum YieldResult {
435 YIELD_SWITCHED = 1, // caller descheduled, other ready threads exist & ran
436 YIELD_NONEREADY = 0, // No other runnable/ready threads.
437 // platform-specific yield return immediately
438 YIELD_UNKNOWN = -1 // Unknown: platform doesn't support _SWITCHED or _NONEREADY
439 // YIELD_SWITCHED and YIELD_NONREADY imply the platform supports a "strong"
440 // yield that can be used in lieu of blocking.
441 } ;
442 static YieldResult NakedYield () ;
443 static void yield_all(int attempts = 0); // Yields to all other threads including lower priority
444 static void loop_breaker(int attempts); // called from within tight loops to possibly influence time-sharing
445 static OSReturn set_priority(Thread* thread, ThreadPriority priority);
446 static OSReturn get_priority(const Thread* const thread, ThreadPriority& priority);
448 static void interrupt(Thread* thread);
449 static bool is_interrupted(Thread* thread, bool clear_interrupted);
451 static int pd_self_suspend_thread(Thread* thread);
453 static ExtendedPC fetch_frame_from_context(void* ucVoid, intptr_t** sp, intptr_t** fp);
454 static frame fetch_frame_from_context(void* ucVoid);
456 static ExtendedPC get_thread_pc(Thread *thread);
457 static void breakpoint();
459 static address current_stack_pointer();
460 static address current_stack_base();
461 static size_t current_stack_size();
463 static void verify_stack_alignment() PRODUCT_RETURN;
465 static int message_box(const char* title, const char* message);
466 static char* do_you_want_to_debug(const char* message);
468 // run cmd in a separate process and return its exit code; or -1 on failures
469 static int fork_and_exec(char *cmd);
471 // Set file to send error reports.
472 static void set_error_file(const char *logfile);
474 // os::exit() is merged with vm_exit()
475 // static void exit(int num);
477 // Terminate the VM, but don't exit the process
478 static void shutdown();
480 // Terminate with an error. Default is to generate a core file on platforms
481 // that support such things. This calls shutdown() and then aborts.
482 static void abort(bool dump_core = true);
484 // Die immediately, no exit hook, no abort hook, no cleanup.
485 static void die();
487 // File i/o operations
488 static const int default_file_open_flags();
489 static int open(const char *path, int oflag, int mode);
490 static FILE* open(int fd, const char* mode);
491 static int close(int fd);
492 static jlong lseek(int fd, jlong offset, int whence);
493 static char* native_path(char *path);
494 static int ftruncate(int fd, jlong length);
495 static int fsync(int fd);
496 static int available(int fd, jlong *bytes);
498 //File i/o operations
500 static size_t read(int fd, void *buf, unsigned int nBytes);
501 static size_t restartable_read(int fd, void *buf, unsigned int nBytes);
502 static size_t write(int fd, const void *buf, unsigned int nBytes);
504 // Reading directories.
505 static DIR* opendir(const char* dirname);
506 static int readdir_buf_size(const char *path);
507 static struct dirent* readdir(DIR* dirp, dirent* dbuf);
508 static int closedir(DIR* dirp);
510 // Dynamic library extension
511 static const char* dll_file_extension();
513 static const char* get_temp_directory();
514 static const char* get_current_directory(char *buf, size_t buflen);
516 // Builds a platform-specific full library path given a ld path and lib name
517 // Returns true if buffer contains full path to existing file, false otherwise
518 static bool dll_build_name(char* buffer, size_t size,
519 const char* pathname, const char* fname);
521 // Symbol lookup, find nearest function name; basically it implements
522 // dladdr() for all platforms. Name of the nearest function is copied
523 // to buf. Distance from its base address is optionally returned as offset.
524 // If function name is not found, buf[0] is set to '\0' and offset is
525 // set to -1 (if offset is non-NULL).
526 static bool dll_address_to_function_name(address addr, char* buf,
527 int buflen, int* offset);
529 // Locate DLL/DSO. On success, full path of the library is copied to
530 // buf, and offset is optionally set to be the distance between addr
531 // and the library's base address. On failure, buf[0] is set to '\0'
532 // and offset is set to -1 (if offset is non-NULL).
533 static bool dll_address_to_library_name(address addr, char* buf,
534 int buflen, int* offset);
536 // Find out whether the pc is in the static code for jvm.dll/libjvm.so.
537 static bool address_is_in_vm(address addr);
539 // Loads .dll/.so and
540 // in case of error it checks if .dll/.so was built for the
541 // same architecture as Hotspot is running on
542 static void* dll_load(const char *name, char *ebuf, int ebuflen);
544 // lookup symbol in a shared library
545 static void* dll_lookup(void* handle, const char* name);
547 // Unload library
548 static void dll_unload(void *lib);
550 // Return the handle of this process
551 static void* get_default_process_handle();
553 // Check for static linked agent library
554 static bool find_builtin_agent(AgentLibrary *agent_lib, const char *syms[],
555 size_t syms_len);
557 // Find agent entry point
558 static void *find_agent_function(AgentLibrary *agent_lib, bool check_lib,
559 const char *syms[], size_t syms_len);
561 // Print out system information; they are called by fatal error handler.
562 // Output format may be different on different platforms.
563 static void print_os_info(outputStream* st);
564 static void print_os_info_brief(outputStream* st);
565 static void print_cpu_info(outputStream* st);
566 static void pd_print_cpu_info(outputStream* st);
567 static void print_memory_info(outputStream* st);
568 static void print_dll_info(outputStream* st);
569 static void print_environment_variables(outputStream* st, const char** env_list, char* buffer, int len);
570 static void print_context(outputStream* st, void* context);
571 static void print_register_info(outputStream* st, void* context);
572 static void print_siginfo(outputStream* st, void* siginfo);
573 static void print_signal_handlers(outputStream* st, char* buf, size_t buflen);
574 static void print_date_and_time(outputStream* st);
576 static void print_location(outputStream* st, intptr_t x, bool verbose = false);
577 static size_t lasterror(char *buf, size_t len);
578 static int get_last_error();
580 // Determines whether the calling process is being debugged by a user-mode debugger.
581 static bool is_debugger_attached();
583 // wait for a key press if PauseAtExit is set
584 static void wait_for_keypress_at_exit(void);
586 // The following two functions are used by fatal error handler to trace
587 // native (C) frames. They are not part of frame.hpp/frame.cpp because
588 // frame.hpp/cpp assume thread is JavaThread, and also because different
589 // OS/compiler may have different convention or provide different API to
590 // walk C frames.
591 //
592 // We don't attempt to become a debugger, so we only follow frames if that
593 // does not require a lookup in the unwind table, which is part of the binary
594 // file but may be unsafe to read after a fatal error. So on x86, we can
595 // only walk stack if %ebp is used as frame pointer; on ia64, it's not
596 // possible to walk C stack without having the unwind table.
597 static bool is_first_C_frame(frame *fr);
598 static frame get_sender_for_C_frame(frame *fr);
600 // return current frame. pc() and sp() are set to NULL on failure.
601 static frame current_frame();
603 static void print_hex_dump(outputStream* st, address start, address end, int unitsize);
605 // returns a string to describe the exception/signal;
606 // returns NULL if exception_code is not an OS exception/signal.
607 static const char* exception_name(int exception_code, char* buf, size_t buflen);
609 // Returns native Java library, loads if necessary
610 static void* native_java_library();
612 // Fills in path to jvm.dll/libjvm.so (used by the Disassembler)
613 static void jvm_path(char *buf, jint buflen);
615 // Returns true if we are running in a headless jre.
616 static bool is_headless_jre();
618 // JNI names
619 static void print_jni_name_prefix_on(outputStream* st, int args_size);
620 static void print_jni_name_suffix_on(outputStream* st, int args_size);
622 // File conventions
623 static const char* file_separator();
624 static const char* line_separator();
625 static const char* path_separator();
627 // Init os specific system properties values
628 static void init_system_properties_values();
630 // IO operations, non-JVM_ version.
631 static int stat(const char* path, struct stat* sbuf);
632 static bool dir_is_empty(const char* path);
634 // IO operations on binary files
635 static int create_binary_file(const char* path, bool rewrite_existing);
636 static jlong current_file_offset(int fd);
637 static jlong seek_to_file_offset(int fd, jlong offset);
639 // Thread Local Storage
640 static int allocate_thread_local_storage();
641 static void thread_local_storage_at_put(int index, void* value);
642 static void* thread_local_storage_at(int index);
643 static void free_thread_local_storage(int index);
645 // Stack walk
646 static address get_caller_pc(int n = 0);
648 // General allocation (must be MT-safe)
649 static void* malloc (size_t size, MEMFLAGS flags, address caller_pc = 0);
650 static void* realloc (void *memblock, size_t size, MEMFLAGS flags, address caller_pc = 0);
651 static void free (void *memblock, MEMFLAGS flags = mtNone);
652 static bool check_heap(bool force = false); // verify C heap integrity
653 static char* strdup(const char *, MEMFLAGS flags = mtInternal); // Like strdup
655 #ifndef PRODUCT
656 static julong num_mallocs; // # of calls to malloc/realloc
657 static julong alloc_bytes; // # of bytes allocated
658 static julong num_frees; // # of calls to free
659 static julong free_bytes; // # of bytes freed
660 #endif
662 // SocketInterface (ex HPI SocketInterface )
663 static int socket(int domain, int type, int protocol);
664 static int socket_close(int fd);
665 static int socket_shutdown(int fd, int howto);
666 static int recv(int fd, char* buf, size_t nBytes, uint flags);
667 static int send(int fd, char* buf, size_t nBytes, uint flags);
668 static int raw_send(int fd, char* buf, size_t nBytes, uint flags);
669 static int timeout(int fd, long timeout);
670 static int listen(int fd, int count);
671 static int connect(int fd, struct sockaddr* him, socklen_t len);
672 static int bind(int fd, struct sockaddr* him, socklen_t len);
673 static int accept(int fd, struct sockaddr* him, socklen_t* len);
674 static int recvfrom(int fd, char* buf, size_t nbytes, uint flags,
675 struct sockaddr* from, socklen_t* fromlen);
676 static int get_sock_name(int fd, struct sockaddr* him, socklen_t* len);
677 static int sendto(int fd, char* buf, size_t len, uint flags,
678 struct sockaddr* to, socklen_t tolen);
679 static int socket_available(int fd, jint* pbytes);
681 static int get_sock_opt(int fd, int level, int optname,
682 char* optval, socklen_t* optlen);
683 static int set_sock_opt(int fd, int level, int optname,
684 const char* optval, socklen_t optlen);
685 static int get_host_name(char* name, int namelen);
687 static struct hostent* get_host_by_name(char* name);
689 // Support for signals (see JVM_RaiseSignal, JVM_RegisterSignal)
690 static void signal_init();
691 static void signal_init_pd();
692 static void signal_notify(int signal_number);
693 static void* signal(int signal_number, void* handler);
694 static void signal_raise(int signal_number);
695 static int signal_wait();
696 static int signal_lookup();
697 static void* user_handler();
698 static void terminate_signal_thread();
699 static int sigexitnum_pd();
701 // random number generation
702 static long random(); // return 32bit pseudorandom number
703 static void init_random(long initval); // initialize random sequence
705 // Structured OS Exception support
706 static void os_exception_wrapper(java_call_t f, JavaValue* value, methodHandle* method, JavaCallArguments* args, Thread* thread);
708 // On Windows this will create an actual minidump, on Linux/Solaris it will simply check core dump limits
709 static void check_or_create_dump(void* exceptionRecord, void* contextRecord, char* buffer, size_t bufferSize);
711 // Get the default path to the core file
712 // Returns the length of the string
713 static int get_core_path(char* buffer, size_t bufferSize);
715 // JVMTI & JVM monitoring and management support
716 // The thread_cpu_time() and current_thread_cpu_time() are only
717 // supported if is_thread_cpu_time_supported() returns true.
718 // They are not supported on Solaris T1.
720 // Thread CPU Time - return the fast estimate on a platform
721 // On Solaris - call gethrvtime (fast) - user time only
722 // On Linux - fast clock_gettime where available - user+sys
723 // - otherwise: very slow /proc fs - user+sys
724 // On Windows - GetThreadTimes - user+sys
725 static jlong current_thread_cpu_time();
726 static jlong thread_cpu_time(Thread* t);
728 // Thread CPU Time with user_sys_cpu_time parameter.
729 //
730 // If user_sys_cpu_time is true, user+sys time is returned.
731 // Otherwise, only user time is returned
732 static jlong current_thread_cpu_time(bool user_sys_cpu_time);
733 static jlong thread_cpu_time(Thread* t, bool user_sys_cpu_time);
735 // Return a bunch of info about the timers.
736 // Note that the returned info for these two functions may be different
737 // on some platforms
738 static void current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr);
739 static void thread_cpu_time_info(jvmtiTimerInfo *info_ptr);
741 static bool is_thread_cpu_time_supported();
743 // System loadavg support. Returns -1 if load average cannot be obtained.
744 static int loadavg(double loadavg[], int nelem);
746 // Hook for os specific jvm options that we don't want to abort on seeing
747 static bool obsolete_option(const JavaVMOption *option);
749 // Extensions
750 #include "runtime/os_ext.hpp"
752 public:
753 class CrashProtectionCallback : public StackObj {
754 public:
755 virtual void call() = 0;
756 };
758 // Platform dependent stuff
759 #ifdef TARGET_OS_FAMILY_linux
760 # include "os_linux.hpp"
761 # include "os_posix.hpp"
762 #endif
763 #ifdef TARGET_OS_FAMILY_solaris
764 # include "os_solaris.hpp"
765 # include "os_posix.hpp"
766 #endif
767 #ifdef TARGET_OS_FAMILY_windows
768 # include "os_windows.hpp"
769 #endif
770 #ifdef TARGET_OS_FAMILY_bsd
771 # include "os_posix.hpp"
772 # include "os_bsd.hpp"
773 #endif
774 #ifdef TARGET_OS_ARCH_linux_x86
775 # include "os_linux_x86.hpp"
776 #endif
777 #ifdef TARGET_OS_ARCH_linux_sparc
778 # include "os_linux_sparc.hpp"
779 #endif
780 #ifdef TARGET_OS_ARCH_linux_zero
781 # include "os_linux_zero.hpp"
782 #endif
783 #ifdef TARGET_OS_ARCH_solaris_x86
784 # include "os_solaris_x86.hpp"
785 #endif
786 #ifdef TARGET_OS_ARCH_solaris_sparc
787 # include "os_solaris_sparc.hpp"
788 #endif
789 #ifdef TARGET_OS_ARCH_windows_x86
790 # include "os_windows_x86.hpp"
791 #endif
792 #ifdef TARGET_OS_ARCH_linux_arm
793 # include "os_linux_arm.hpp"
794 #endif
795 #ifdef TARGET_OS_ARCH_linux_ppc
796 # include "os_linux_ppc.hpp"
797 #endif
798 #ifdef TARGET_OS_ARCH_bsd_x86
799 # include "os_bsd_x86.hpp"
800 #endif
801 #ifdef TARGET_OS_ARCH_bsd_zero
802 # include "os_bsd_zero.hpp"
803 #endif
805 public:
806 #ifndef PLATFORM_PRINT_NATIVE_STACK
807 // No platform-specific code for printing the native stack.
808 static bool platform_print_native_stack(outputStream* st, void* context,
809 char *buf, int buf_size) {
810 return false;
811 }
812 #endif
814 // debugging support (mostly used by debug.cpp but also fatal error handler)
815 static bool find(address pc, outputStream* st = tty); // OS specific function to make sense out of an address
817 static bool dont_yield(); // when true, JVM_Yield() is nop
818 static void print_statistics();
820 // Thread priority helpers (implemented in OS-specific part)
821 static OSReturn set_native_priority(Thread* thread, int native_prio);
822 static OSReturn get_native_priority(const Thread* const thread, int* priority_ptr);
823 static int java_to_os_priority[CriticalPriority + 1];
824 // Hint to the underlying OS that a task switch would not be good.
825 // Void return because it's a hint and can fail.
826 static void hint_no_preempt();
828 // Used at creation if requested by the diagnostic flag PauseAtStartup.
829 // Causes the VM to wait until an external stimulus has been applied
830 // (for Unix, that stimulus is a signal, for Windows, an external
831 // ResumeThread call)
832 static void pause();
834 // Builds a platform dependent Agent_OnLoad_<libname> function name
835 // which is used to find statically linked in agents.
836 static char* build_agent_function_name(const char *sym, const char *cname,
837 bool is_absolute_path);
839 class SuspendedThreadTaskContext {
840 public:
841 SuspendedThreadTaskContext(Thread* thread, void *ucontext) : _thread(thread), _ucontext(ucontext) {}
842 Thread* thread() const { return _thread; }
843 void* ucontext() const { return _ucontext; }
844 private:
845 Thread* _thread;
846 void* _ucontext;
847 };
849 class SuspendedThreadTask {
850 public:
851 SuspendedThreadTask(Thread* thread) : _thread(thread), _done(false) {}
852 virtual ~SuspendedThreadTask() {}
853 void run();
854 bool is_done() { return _done; }
855 virtual void do_task(const SuspendedThreadTaskContext& context) = 0;
856 protected:
857 private:
858 void internal_do_task();
859 Thread* _thread;
860 bool _done;
861 };
863 #ifndef TARGET_OS_FAMILY_windows
864 // Suspend/resume support
865 // Protocol:
866 //
867 // a thread starts in SR_RUNNING
868 //
869 // SR_RUNNING can go to
870 // * SR_SUSPEND_REQUEST when the WatcherThread wants to suspend it
871 // SR_SUSPEND_REQUEST can go to
872 // * SR_RUNNING if WatcherThread decides it waited for SR_SUSPENDED too long (timeout)
873 // * SR_SUSPENDED if the stopped thread receives the signal and switches state
874 // SR_SUSPENDED can go to
875 // * SR_WAKEUP_REQUEST when the WatcherThread has done the work and wants to resume
876 // SR_WAKEUP_REQUEST can go to
877 // * SR_RUNNING when the stopped thread receives the signal
878 // * SR_WAKEUP_REQUEST on timeout (resend the signal and try again)
879 class SuspendResume {
880 public:
881 enum State {
882 SR_RUNNING,
883 SR_SUSPEND_REQUEST,
884 SR_SUSPENDED,
885 SR_WAKEUP_REQUEST
886 };
888 private:
889 volatile State _state;
891 private:
892 /* try to switch state from state "from" to state "to"
893 * returns the state set after the method is complete
894 */
895 State switch_state(State from, State to);
897 public:
898 SuspendResume() : _state(SR_RUNNING) { }
900 State state() const { return _state; }
902 State request_suspend() {
903 return switch_state(SR_RUNNING, SR_SUSPEND_REQUEST);
904 }
906 State cancel_suspend() {
907 return switch_state(SR_SUSPEND_REQUEST, SR_RUNNING);
908 }
910 State suspended() {
911 return switch_state(SR_SUSPEND_REQUEST, SR_SUSPENDED);
912 }
914 State request_wakeup() {
915 return switch_state(SR_SUSPENDED, SR_WAKEUP_REQUEST);
916 }
918 State running() {
919 return switch_state(SR_WAKEUP_REQUEST, SR_RUNNING);
920 }
922 bool is_running() const {
923 return _state == SR_RUNNING;
924 }
926 bool is_suspend_request() const {
927 return _state == SR_SUSPEND_REQUEST;
928 }
930 bool is_suspended() const {
931 return _state == SR_SUSPENDED;
932 }
933 };
934 #endif
937 protected:
938 static long _rand_seed; // seed for random number generator
939 static int _processor_count; // number of processors
941 static char* format_boot_path(const char* format_string,
942 const char* home,
943 int home_len,
944 char fileSep,
945 char pathSep);
946 static bool set_boot_path(char fileSep, char pathSep);
947 static char** split_path(const char* path, int* n);
949 };
951 // Note that "PAUSE" is almost always used with synchronization
952 // so arguably we should provide Atomic::SpinPause() instead
953 // of the global SpinPause() with C linkage.
954 // It'd also be eligible for inlining on many platforms.
956 extern "C" int SpinPause();
958 #endif // SHARE_VM_RUNTIME_OS_HPP