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