1 /*
2 * Copyright (c) 2003, 2011, Oracle and/or its affiliates. All rights reserved.
3 * Copyright 2007, 2008, 2009, 2010 Red Hat, Inc.
4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
5 *
6 * This code is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License version 2 only, as
8 * published by the Free Software Foundation.
9 *
10 * This code is distributed in the hope that it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
13 * version 2 for more details (a copy is included in the LICENSE file that
14 * accompanied this code).
15 *
16 * You should have received a copy of the GNU General Public License version
17 * 2 along with this work; if not, write to the Free Software Foundation,
18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
19 *
20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
21 * or visit www.oracle.com if you need additional information or have any
22 * questions.
23 *
24 */
25
26 #if defined(_ALLBSD_SOURCE) && !defined(__APPLE__) && !defined(__NetBSD__)
27 # include <pthread_np.h> /* For pthread_attr_get_np */
28 #endif
29
30 // no precompiled headers
31 #include "assembler_zero.inline.hpp"
32 #include "classfile/classLoader.hpp"
33 #include "classfile/systemDictionary.hpp"
34 #include "classfile/vmSymbols.hpp"
35 #include "code/icBuffer.hpp"
36 #include "code/vtableStubs.hpp"
37 #include "interpreter/interpreter.hpp"
38 #include "jvm_bsd.h"
39 #include "memory/allocation.inline.hpp"
40 #include "mutex_bsd.inline.hpp"
41 #include "nativeInst_zero.hpp"
42 #include "os_share_bsd.hpp"
43 #include "prims/jniFastGetField.hpp"
44 #include "prims/jvm.h"
45 #include "prims/jvm_misc.hpp"
46 #include "runtime/arguments.hpp"
47 #include "runtime/extendedPC.hpp"
48 #include "runtime/frame.inline.hpp"
49 #include "runtime/interfaceSupport.hpp"
50 #include "runtime/java.hpp"
51 #include "runtime/javaCalls.hpp"
52 #include "runtime/mutexLocker.hpp"
53 #include "runtime/osThread.hpp"
54 #include "runtime/sharedRuntime.hpp"
55 #include "runtime/stubRoutines.hpp"
56 #include "runtime/timer.hpp"
57 #include "thread_bsd.inline.hpp"
58 #include "utilities/events.hpp"
59 #include "utilities/vmError.hpp"
60 #ifdef COMPILER1
61 #include "c1/c1_Runtime1.hpp"
62 #endif
63 #ifdef COMPILER2
64 #include "opto/runtime.hpp"
65 #endif
66
67 address os::current_stack_pointer() {
68 address dummy = (address) &dummy;
69 return dummy;
70 }
71
72 frame os::get_sender_for_C_frame(frame* fr) {
73 ShouldNotCallThis();
74 }
75
76 frame os::current_frame() {
77 // The only thing that calls this is the stack printing code in
78 // VMError::report:
79 // - Step 110 (printing stack bounds) uses the sp in the frame
80 // to determine the amount of free space on the stack. We
81 // set the sp to a close approximation of the real value in
82 // order to allow this step to complete.
83 // - Step 120 (printing native stack) tries to walk the stack.
84 // The frame we create has a NULL pc, which is ignored as an
85 // invalid frame.
86 frame dummy = frame();
87 dummy.set_sp((intptr_t *) current_stack_pointer());
88 return dummy;
89 }
90
91 char* os::non_memory_address_word() {
92 // Must never look like an address returned by reserve_memory,
93 // even in its subfields (as defined by the CPU immediate fields,
94 // if the CPU splits constants across multiple instructions).
95 #ifdef SPARC
96 // On SPARC, 0 != %hi(any real address), because there is no
97 // allocation in the first 1Kb of the virtual address space.
98 return (char *) 0;
99 #else
100 // This is the value for x86; works pretty well for PPC too.
101 return (char *) -1;
102 #endif // SPARC
103 }
104
105 void os::initialize_thread() {
106 // Nothing to do.
107 }
108
109 address os::Bsd::ucontext_get_pc(ucontext_t* uc) {
110 ShouldNotCallThis();
111 }
112
113 ExtendedPC os::fetch_frame_from_context(void* ucVoid,
114 intptr_t** ret_sp,
115 intptr_t** ret_fp) {
116 ShouldNotCallThis();
117 }
118
119 frame os::fetch_frame_from_context(void* ucVoid) {
120 ShouldNotCallThis();
121 }
122
123 extern "C" JNIEXPORT int
124 JVM_handle_bsd_signal(int sig,
125 siginfo_t* info,
126 void* ucVoid,
127 int abort_if_unrecognized) {
128 ucontext_t* uc = (ucontext_t*) ucVoid;
129
130 Thread* t = ThreadLocalStorage::get_thread_slow();
131
132 SignalHandlerMark shm(t);
133
134 // Note: it's not uncommon that JNI code uses signal/sigset to
135 // install then restore certain signal handler (e.g. to temporarily
136 // block SIGPIPE, or have a SIGILL handler when detecting CPU
137 // type). When that happens, JVM_handle_bsd_signal() might be
138 // invoked with junk info/ucVoid. To avoid unnecessary crash when
139 // libjsig is not preloaded, try handle signals that do not require
140 // siginfo/ucontext first.
141
142 if (sig == SIGPIPE || sig == SIGXFSZ) {
143 // allow chained handler to go first
144 if (os::Bsd::chained_handler(sig, info, ucVoid)) {
145 return true;
146 } else {
147 if (PrintMiscellaneous && (WizardMode || Verbose)) {
148 char buf[64];
149 warning("Ignoring %s - see bugs 4229104 or 646499219",
150 os::exception_name(sig, buf, sizeof(buf)));
151 }
152 return true;
153 }
154 }
155
156 JavaThread* thread = NULL;
157 VMThread* vmthread = NULL;
158 if (os::Bsd::signal_handlers_are_installed) {
159 if (t != NULL ){
160 if(t->is_Java_thread()) {
161 thread = (JavaThread*)t;
162 }
163 else if(t->is_VM_thread()){
164 vmthread = (VMThread *)t;
165 }
166 }
167 }
168
169 if (info != NULL && thread != NULL) {
170 // Handle ALL stack overflow variations here
171 if (sig == SIGSEGV) {
172 address addr = (address) info->si_addr;
173
174 // check if fault address is within thread stack
175 if (addr < thread->stack_base() &&
176 addr >= thread->stack_base() - thread->stack_size()) {
177 // stack overflow
178 if (thread->in_stack_yellow_zone(addr)) {
179 thread->disable_stack_yellow_zone();
180 ShouldNotCallThis();
181 }
182 else if (thread->in_stack_red_zone(addr)) {
183 thread->disable_stack_red_zone();
184 ShouldNotCallThis();
185 }
186 #ifndef _ALLBSD_SOURCE
187 else {
188 // Accessing stack address below sp may cause SEGV if
189 // current thread has MAP_GROWSDOWN stack. This should
190 // only happen when current thread was created by user
191 // code with MAP_GROWSDOWN flag and then attached to VM.
192 // See notes in os_bsd.cpp.
193 if (thread->osthread()->expanding_stack() == 0) {
194 thread->osthread()->set_expanding_stack();
195 if (os::Bsd::manually_expand_stack(thread, addr)) {
196 thread->osthread()->clear_expanding_stack();
197 return true;
198 }
199 thread->osthread()->clear_expanding_stack();
200 }
201 else {
202 fatal("recursive segv. expanding stack.");
203 }
204 }
205 #endif
206 }
207 }
208
209 /*if (thread->thread_state() == _thread_in_Java) {
210 ShouldNotCallThis();
211 }
212 else*/ if (thread->thread_state() == _thread_in_vm &&
213 sig == SIGBUS && thread->doing_unsafe_access()) {
214 ShouldNotCallThis();
215 }
216
217 // jni_fast_Get<Primitive>Field can trap at certain pc's if a GC
218 // kicks in and the heap gets shrunk before the field access.
219 /*if (sig == SIGSEGV || sig == SIGBUS) {
220 address addr = JNI_FastGetField::find_slowcase_pc(pc);
221 if (addr != (address)-1) {
222 stub = addr;
223 }
224 }*/
225
226 // Check to see if we caught the safepoint code in the process
227 // of write protecting the memory serialization page. It write
228 // enables the page immediately after protecting it so we can
229 // just return to retry the write.
230 if (sig == SIGSEGV &&
231 os::is_memory_serialize_page(thread, (address) info->si_addr)) {
232 // Block current thread until permission is restored.
233 os::block_on_serialize_page_trap();
234 return true;
235 }
236 }
237
238 // signal-chaining
239 if (os::Bsd::chained_handler(sig, info, ucVoid)) {
240 return true;
241 }
242
243 if (!abort_if_unrecognized) {
244 // caller wants another chance, so give it to him
245 return false;
246 }
247
248 #ifndef PRODUCT
249 if (sig == SIGSEGV) {
250 fatal("\n#"
251 "\n# /--------------------\\"
252 "\n# | segmentation fault |"
253 "\n# \\---\\ /--------------/"
254 "\n# /"
255 "\n# [-] |\\_/| "
256 "\n# (+)=C |o o|__ "
257 "\n# | | =-*-=__\\ "
258 "\n# OOO c_c_(___)");
259 }
260 #endif // !PRODUCT
261
262 const char *fmt = "caught unhandled signal %d";
263 char buf[64];
264
265 sprintf(buf, fmt, sig);
266 fatal(buf);
267 }
268
269 void os::Bsd::init_thread_fpu_state(void) {
270 // Nothing to do
271 }
272
273 #ifndef _ALLBSD_SOURCE
274 int os::Bsd::get_fpu_control_word() {
275 ShouldNotCallThis();
276 }
277
278 void os::Bsd::set_fpu_control_word(int fpu) {
279 ShouldNotCallThis();
280 }
281 #endif
282
283 bool os::is_allocatable(size_t bytes) {
284 #ifdef _LP64
285 return true;
286 #else
287 if (bytes < 2 * G) {
288 return true;
289 }
290
291 char* addr = reserve_memory(bytes, NULL);
292
293 if (addr != NULL) {
294 release_memory(addr, bytes);
295 }
296
297 return addr != NULL;
298 #endif // _LP64
299 }
300
301 ///////////////////////////////////////////////////////////////////////////////
302 // thread stack
303
304 size_t os::Bsd::min_stack_allowed = 64 * K;
305
306 bool os::Bsd::supports_variable_stack_size() {
307 return true;
308 }
309
310 size_t os::Bsd::default_stack_size(os::ThreadType thr_type) {
311 #ifdef _LP64
312 size_t s = (thr_type == os::compiler_thread ? 4 * M : 1 * M);
313 #else
314 size_t s = (thr_type == os::compiler_thread ? 2 * M : 512 * K);
315 #endif // _LP64
316 return s;
317 }
318
319 size_t os::Bsd::default_guard_size(os::ThreadType thr_type) {
320 // Only enable glibc guard pages for non-Java threads
321 // (Java threads have HotSpot guard pages)
322 return (thr_type == java_thread ? 0 : page_size());
323 }
324
325 static void current_stack_region(address *bottom, size_t *size) {
326 address stack_bottom;
327 address stack_top;
328 size_t stack_bytes;
329
330 #ifdef __APPLE__
331 pthread_t self = pthread_self();
332 stack_top = (address) pthread_get_stackaddr_np(self);
333 stack_bytes = pthread_get_stacksize_np(self);
334 stack_bottom = stack_top - stack_bytes;
335 #elif defined(__OpenBSD__)
336 stack_t ss;
337 int rslt = pthread_stackseg_np(pthread_self(), &ss);
338
339 if (rslt != 0)
340 fatal(err_msg("pthread_stackseg_np failed with err = %d", rslt));
341
342 stack_top = (address) ss.ss_sp;
343 stack_bytes = ss.ss_size;
344 stack_bottom = stacktop - stack_bytes;
345 #elif defined(_ALLBSD_SOURCE)
346 pthread_attr_t attr;
347
348 int rslt = pthread_attr_init(&attr);
349
350 // JVM needs to know exact stack location, abort if it fails
351 if (rslt != 0)
352 fatal(err_msg("pthread_attr_init failed with err = %d", rslt));
353
354 rslt = pthread_attr_get_np(pthread_self(), &attr);
355
356 if (rslt != 0)
357 fatal(err_msg("pthread_attr_get_np failed with err = %d", rslt));
358
359 if (pthread_attr_getstackaddr(&attr, (void **) &stack_bottom) != 0 ||
360 pthread_attr_getstacksize(&attr, &stack_bytes) != 0) {
361 fatal("Can not locate current stack attributes!");
362 }
363
364 pthread_attr_destroy(&attr);
365
366 stack_top = stack_bottom + stack_bytes;
367 #else /* Linux */
368 pthread_attr_t attr;
369 int res = pthread_getattr_np(pthread_self(), &attr);
370 if (res != 0) {
371 if (res == ENOMEM) {
372 vm_exit_out_of_memory(0, "pthread_getattr_np");
373 }
374 else {
375 fatal(err_msg("pthread_getattr_np failed with errno = %d", res));
376 }
377 }
378
379 res = pthread_attr_getstack(&attr, (void **) &stack_bottom, &stack_bytes);
380 if (res != 0) {
381 fatal(err_msg("pthread_attr_getstack failed with errno = %d", res));
382 }
383 stack_top = stack_bottom + stack_bytes;
384
385 // The block of memory returned by pthread_attr_getstack() includes
386 // guard pages where present. We need to trim these off.
387 size_t page_bytes = os::Bsd::page_size();
388 assert(((intptr_t) stack_bottom & (page_bytes - 1)) == 0, "unaligned stack");
389
390 size_t guard_bytes;
391 res = pthread_attr_getguardsize(&attr, &guard_bytes);
392 if (res != 0) {
393 fatal(err_msg("pthread_attr_getguardsize failed with errno = %d", res));
394 }
395 int guard_pages = align_size_up(guard_bytes, page_bytes) / page_bytes;
396 assert(guard_bytes == guard_pages * page_bytes, "unaligned guard");
397
398 #ifdef IA64
399 // IA64 has two stacks sharing the same area of memory, a normal
400 // stack growing downwards and a register stack growing upwards.
401 // Guard pages, if present, are in the centre. This code splits
402 // the stack in two even without guard pages, though in theory
403 // there's nothing to stop us allocating more to the normal stack
404 // or more to the register stack if one or the other were found
405 // to grow faster.
406 int total_pages = align_size_down(stack_bytes, page_bytes) / page_bytes;
407 stack_bottom += (total_pages - guard_pages) / 2 * page_bytes;
408 #endif // IA64
409
410 stack_bottom += guard_bytes;
411
412 pthread_attr_destroy(&attr);
413
414 // The initial thread has a growable stack, and the size reported
415 // by pthread_attr_getstack is the maximum size it could possibly
416 // be given what currently mapped. This can be huge, so we cap it.
417 if (os::Bsd::is_initial_thread()) {
418 stack_bytes = stack_top - stack_bottom;
419
420 if (stack_bytes > JavaThread::stack_size_at_create())
421 stack_bytes = JavaThread::stack_size_at_create();
422
423 stack_bottom = stack_top - stack_bytes;
424 }
425 #endif
426
427 assert(os::current_stack_pointer() >= stack_bottom, "should do");
428 assert(os::current_stack_pointer() < stack_top, "should do");
429
430 *bottom = stack_bottom;
431 *size = stack_top - stack_bottom;
432 }
433
434 address os::current_stack_base() {
435 address bottom;
436 size_t size;
437 current_stack_region(&bottom, &size);
438 return bottom + size;
439 }
440
441 size_t os::current_stack_size() {
442 // stack size includes normal stack and HotSpot guard pages
443 address bottom;
444 size_t size;
445 current_stack_region(&bottom, &size);
446 return size;
447 }
448
449 /////////////////////////////////////////////////////////////////////////////
450 // helper functions for fatal error handler
451
452 void os::print_context(outputStream* st, void* context) {
453 ShouldNotCallThis();
454 }
455
456 void os::print_register_info(outputStream *st, void *context) {
457 ShouldNotCallThis();
458 }
459
460 /////////////////////////////////////////////////////////////////////////////
461 // Stubs for things that would be in bsd_zero.s if it existed.
462 // You probably want to disassemble these monkeys to check they're ok.
463
464 extern "C" {
465 int SpinPause() {
466 }
467
468 int SafeFetch32(int *adr, int errValue) {
469 int value = errValue;
470 value = *adr;
471 return value;
472 }
473 intptr_t SafeFetchN(intptr_t *adr, intptr_t errValue) {
474 intptr_t value = errValue;
475 value = *adr;
476 return value;
477 }
478
479 void _Copy_conjoint_jshorts_atomic(jshort* from, jshort* to, size_t count) {
480 if (from > to) {
481 jshort *end = from + count;
482 while (from < end)
483 *(to++) = *(from++);
484 }
485 else if (from < to) {
486 jshort *end = from;
487 from += count - 1;
488 to += count - 1;
489 while (from >= end)
490 *(to--) = *(from--);
491 }
492 }
493 void _Copy_conjoint_jints_atomic(jint* from, jint* to, size_t count) {
494 if (from > to) {
495 jint *end = from + count;
496 while (from < end)
497 *(to++) = *(from++);
498 }
499 else if (from < to) {
500 jint *end = from;
501 from += count - 1;
502 to += count - 1;
503 while (from >= end)
504 *(to--) = *(from--);
505 }
506 }
507 void _Copy_conjoint_jlongs_atomic(jlong* from, jlong* to, size_t count) {
508 if (from > to) {
509 jlong *end = from + count;
510 while (from < end)
511 os::atomic_copy64(from++, to++);
512 }
513 else if (from < to) {
514 jlong *end = from;
515 from += count - 1;
516 to += count - 1;
517 while (from >= end)
518 os::atomic_copy64(from--, to--);
519 }
520 }
521
522 void _Copy_arrayof_conjoint_bytes(HeapWord* from,
523 HeapWord* to,
524 size_t count) {
525 memmove(to, from, count);
526 }
527 void _Copy_arrayof_conjoint_jshorts(HeapWord* from,
528 HeapWord* to,
529 size_t count) {
530 memmove(to, from, count * 2);
531 }
532 void _Copy_arrayof_conjoint_jints(HeapWord* from,
533 HeapWord* to,
534 size_t count) {
535 memmove(to, from, count * 4);
536 }
537 void _Copy_arrayof_conjoint_jlongs(HeapWord* from,
538 HeapWord* to,
539 size_t count) {
540 memmove(to, from, count * 8);
541 }
542 };
543
544 /////////////////////////////////////////////////////////////////////////////
545 // Implementations of atomic operations not supported by processors.
546 // -- http://gcc.gnu.org/onlinedocs/gcc-4.2.1/gcc/Atomic-Builtins.html
547
548 #ifndef _LP64
549 extern "C" {
550 long long unsigned int __sync_val_compare_and_swap_8(
551 volatile void *ptr,
552 long long unsigned int oldval,
553 long long unsigned int newval) {
554 ShouldNotCallThis();
555 }
556 };
557 #endif // !_LP64