1 /*
2 * Copyright (c) 2003, 2013, 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(__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/thread.inline.hpp"
58 #include "runtime/timer.hpp"
59 #include "utilities/events.hpp"
60 #include "utilities/vmError.hpp"
61
62 address os::current_stack_pointer() {
63 address dummy = (address) &dummy;
64 return dummy;
65 }
66
67 frame os::get_sender_for_C_frame(frame* fr) {
68 ShouldNotCallThis();
69 return frame();
70 }
71
72 frame os::current_frame() {
73 // The only thing that calls this is the stack printing code in
74 // VMError::report:
75 // - Step 110 (printing stack bounds) uses the sp in the frame
76 // to determine the amount of free space on the stack. We
77 // set the sp to a close approximation of the real value in
78 // order to allow this step to complete.
79 // - Step 120 (printing native stack) tries to walk the stack.
80 // The frame we create has a NULL pc, which is ignored as an
81 // invalid frame.
82 frame dummy = frame();
83 dummy.set_sp((intptr_t *) current_stack_pointer());
84 return dummy;
85 }
86
87 char* os::non_memory_address_word() {
88 // Must never look like an address returned by reserve_memory,
89 // even in its subfields (as defined by the CPU immediate fields,
90 // if the CPU splits constants across multiple instructions).
91 #ifdef SPARC
92 // On SPARC, 0 != %hi(any real address), because there is no
93 // allocation in the first 1Kb of the virtual address space.
94 return (char *) 0;
95 #else
96 // This is the value for x86; works pretty well for PPC too.
97 return (char *) -1;
98 #endif // SPARC
99 }
100
101 void os::initialize_thread(Thread* thr) {
102 // Nothing to do.
103 }
104
105 address os::Bsd::ucontext_get_pc(ucontext_t* uc) {
106 ShouldNotCallThis();
107 return NULL;
108 }
109
110 void os::Bsd::ucontext_set_pc(ucontext_t * uc, address pc) {
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 return ExtendedPC();
119 }
120
121 frame os::fetch_frame_from_context(void* ucVoid) {
122 ShouldNotCallThis();
123 return frame();
124 }
125
126 extern "C" JNIEXPORT int
127 JVM_handle_bsd_signal(int sig,
128 siginfo_t* info,
129 void* ucVoid,
130 int abort_if_unrecognized) {
131 ucontext_t* uc = (ucontext_t*) ucVoid;
132
133 Thread* t = ThreadLocalStorage::get_thread_slow();
134
135 SignalHandlerMark shm(t);
136
137 // Note: it's not uncommon that JNI code uses signal/sigset to
138 // install then restore certain signal handler (e.g. to temporarily
139 // block SIGPIPE, or have a SIGILL handler when detecting CPU
140 // type). When that happens, JVM_handle_bsd_signal() might be
141 // invoked with junk info/ucVoid. To avoid unnecessary crash when
142 // libjsig is not preloaded, try handle signals that do not require
143 // siginfo/ucontext first.
144
145 if (sig == SIGPIPE || sig == SIGXFSZ) {
146 // allow chained handler to go first
147 if (os::Bsd::chained_handler(sig, info, ucVoid)) {
148 return true;
149 } else {
150 if (PrintMiscellaneous && (WizardMode || Verbose)) {
151 char buf[64];
152 warning("Ignoring %s - see bugs 4229104 or 646499219",
153 os::exception_name(sig, buf, sizeof(buf)));
154 }
155 return true;
156 }
157 }
158
159 JavaThread* thread = NULL;
160 VMThread* vmthread = NULL;
161 if (os::Bsd::signal_handlers_are_installed) {
162 if (t != NULL ){
163 if(t->is_Java_thread()) {
164 thread = (JavaThread*)t;
165 }
166 else if(t->is_VM_thread()){
167 vmthread = (VMThread *)t;
168 }
169 }
170 }
171
172 if (info != NULL && thread != NULL) {
173 // Handle ALL stack overflow variations here
174 if (sig == SIGSEGV || sig == SIGBUS) {
175 address addr = (address) info->si_addr;
176
177 // check if fault address is within thread stack
178 if (addr < thread->stack_base() &&
179 addr >= thread->stack_base() - thread->stack_size()) {
180 // stack overflow
181 if (thread->in_stack_yellow_zone(addr)) {
182 thread->disable_stack_yellow_zone();
183 ShouldNotCallThis();
184 }
185 else if (thread->in_stack_red_zone(addr)) {
186 thread->disable_stack_red_zone();
187 ShouldNotCallThis();
188 }
189 }
190 }
191
192 /*if (thread->thread_state() == _thread_in_Java) {
193 ShouldNotCallThis();
194 }
195 else*/ if (thread->thread_state() == _thread_in_vm &&
196 sig == SIGBUS && thread->doing_unsafe_access()) {
197 ShouldNotCallThis();
198 }
199
200 // jni_fast_Get<Primitive>Field can trap at certain pc's if a GC
201 // kicks in and the heap gets shrunk before the field access.
202 /*if (sig == SIGSEGV || sig == SIGBUS) {
203 address addr = JNI_FastGetField::find_slowcase_pc(pc);
204 if (addr != (address)-1) {
205 stub = addr;
206 }
207 }*/
208
209 // Check to see if we caught the safepoint code in the process
210 // of write protecting the memory serialization page. It write
211 // enables the page immediately after protecting it so we can
212 // just return to retry the write.
213 if ((sig == SIGSEGV || sig == SIGBUS) &&
214 os::is_memory_serialize_page(thread, (address) info->si_addr)) {
215 // Block current thread until permission is restored.
216 os::block_on_serialize_page_trap();
217 return true;
218 }
219 }
220
221 // signal-chaining
222 if (os::Bsd::chained_handler(sig, info, ucVoid)) {
223 return true;
224 }
225
226 if (!abort_if_unrecognized) {
227 // caller wants another chance, so give it to him
228 return false;
229 }
230
231 #ifndef PRODUCT
232 if (sig == SIGSEGV) {
233 fatal("\n#"
234 "\n# /--------------------\\"
235 "\n# | segmentation fault |"
236 "\n# \\---\\ /--------------/"
237 "\n# /"
238 "\n# [-] |\\_/| "
239 "\n# (+)=C |o o|__ "
240 "\n# | | =-*-=__\\ "
241 "\n# OOO c_c_(___)");
242 }
243 #endif // !PRODUCT
244
245 const char *fmt =
246 "caught unhandled signal " INT32_FORMAT " at address " PTR_FORMAT;
247 char buf[128];
248
249 sprintf(buf, fmt, sig, info->si_addr);
250 fatal(buf);
251 return false;
252 }
253
254 void os::Bsd::init_thread_fpu_state(void) {
255 // Nothing to do
256 }
257
258 bool os::is_allocatable(size_t bytes) {
259 #ifdef _LP64
260 return true;
261 #else
262 if (bytes < 2 * G) {
263 return true;
264 }
265
266 char* addr = reserve_memory(bytes, NULL);
267
268 if (addr != NULL) {
269 release_memory(addr, bytes);
270 }
271
272 return addr != NULL;
273 #endif // _LP64
274 }
275
276 ///////////////////////////////////////////////////////////////////////////////
277 // thread stack
278
279 size_t os::Bsd::min_stack_allowed = 64 * K;
280
281 bool os::Bsd::supports_variable_stack_size() {
282 return true;
283 }
284
285 size_t os::Bsd::default_stack_size(os::ThreadType thr_type) {
286 #ifdef _LP64
287 size_t s = (thr_type == os::compiler_thread ? 4 * M : 1 * M);
288 #else
289 size_t s = (thr_type == os::compiler_thread ? 2 * M : 512 * K);
290 #endif // _LP64
291 return s;
292 }
293
294 size_t os::Bsd::default_guard_size(os::ThreadType thr_type) {
295 // Only enable glibc guard pages for non-Java threads
296 // (Java threads have HotSpot guard pages)
297 return (thr_type == java_thread ? 0 : page_size());
298 }
299
300 static void current_stack_region(address *bottom, size_t *size) {
301 address stack_bottom;
302 address stack_top;
303 size_t stack_bytes;
304
305 #ifdef __APPLE__
306 pthread_t self = pthread_self();
307 stack_top = (address) pthread_get_stackaddr_np(self);
308 stack_bytes = pthread_get_stacksize_np(self);
309 stack_bottom = stack_top - stack_bytes;
310 #elif defined(__OpenBSD__)
311 stack_t ss;
312 int rslt = pthread_stackseg_np(pthread_self(), &ss);
313
314 if (rslt != 0)
315 fatal(err_msg("pthread_stackseg_np failed with err = " INT32_FORMAT,
316 rslt));
317
318 stack_top = (address) ss.ss_sp;
319 stack_bytes = ss.ss_size;
320 stack_bottom = stack_top - stack_bytes;
321 #else
322 pthread_attr_t attr;
323
324 int rslt = pthread_attr_init(&attr);
325
326 // JVM needs to know exact stack location, abort if it fails
327 if (rslt != 0)
328 fatal(err_msg("pthread_attr_init failed with err = " INT32_FORMAT, rslt));
329
330 rslt = pthread_attr_get_np(pthread_self(), &attr);
331
332 if (rslt != 0)
333 fatal(err_msg("pthread_attr_get_np failed with err = " INT32_FORMAT,
334 rslt));
335
336 if (pthread_attr_getstackaddr(&attr, (void **) &stack_bottom) != 0 ||
337 pthread_attr_getstacksize(&attr, &stack_bytes) != 0) {
338 fatal("Can not locate current stack attributes!");
339 }
340
341 pthread_attr_destroy(&attr);
342
343 stack_top = stack_bottom + stack_bytes;
344 #endif
345
346 assert(os::current_stack_pointer() >= stack_bottom, "should do");
347 assert(os::current_stack_pointer() < stack_top, "should do");
348
349 *bottom = stack_bottom;
350 *size = stack_top - stack_bottom;
351 }
352
353 address os::current_stack_base() {
354 address bottom;
355 size_t size;
356 current_stack_region(&bottom, &size);
357 return bottom + size;
358 }
359
360 size_t os::current_stack_size() {
361 // stack size includes normal stack and HotSpot guard pages
362 address bottom;
363 size_t size;
364 current_stack_region(&bottom, &size);
365 return size;
366 }
367
368 /////////////////////////////////////////////////////////////////////////////
369 // helper functions for fatal error handler
370
371 void os::print_context(outputStream* st, void* context) {
372 ShouldNotCallThis();
373 }
374
375 void os::print_register_info(outputStream *st, void *context) {
376 ShouldNotCallThis();
377 }
378
379 /////////////////////////////////////////////////////////////////////////////
380 // Stubs for things that would be in bsd_zero.s if it existed.
381 // You probably want to disassemble these monkeys to check they're ok.
382
383 extern "C" {
384 int SpinPause() {
385 return 1;
386 }
387
388 void _Copy_conjoint_jshorts_atomic(jshort* from, jshort* to, size_t count) {
389 if (from > to) {
390 jshort *end = from + count;
391 while (from < end)
392 *(to++) = *(from++);
393 }
394 else if (from < to) {
395 jshort *end = from;
396 from += count - 1;
397 to += count - 1;
398 while (from >= end)
399 *(to--) = *(from--);
400 }
401 }
402 void _Copy_conjoint_jints_atomic(jint* from, jint* to, size_t count) {
403 if (from > to) {
404 jint *end = from + count;
405 while (from < end)
406 *(to++) = *(from++);
407 }
408 else if (from < to) {
409 jint *end = from;
410 from += count - 1;
411 to += count - 1;
412 while (from >= end)
413 *(to--) = *(from--);
414 }
415 }
416 void _Copy_conjoint_jlongs_atomic(jlong* from, jlong* to, size_t count) {
417 if (from > to) {
418 jlong *end = from + count;
419 while (from < end)
420 os::atomic_copy64(from++, to++);
421 }
422 else if (from < to) {
423 jlong *end = from;
424 from += count - 1;
425 to += count - 1;
426 while (from >= end)
427 os::atomic_copy64(from--, to--);
428 }
429 }
430
431 void _Copy_arrayof_conjoint_bytes(HeapWord* from,
432 HeapWord* to,
433 size_t count) {
434 memmove(to, from, count);
435 }
436 void _Copy_arrayof_conjoint_jshorts(HeapWord* from,
437 HeapWord* to,
438 size_t count) {
439 memmove(to, from, count * 2);
440 }
441 void _Copy_arrayof_conjoint_jints(HeapWord* from,
442 HeapWord* to,
443 size_t count) {
444 memmove(to, from, count * 4);
445 }
446 void _Copy_arrayof_conjoint_jlongs(HeapWord* from,
447 HeapWord* to,
448 size_t count) {
449 memmove(to, from, count * 8);
450 }
451 };
452
453 /////////////////////////////////////////////////////////////////////////////
454 // Implementations of atomic operations not supported by processors.
455 // -- http://gcc.gnu.org/onlinedocs/gcc-4.2.1/gcc/Atomic-Builtins.html
456
457 #ifndef _LP64
458 extern "C" {
459 long long unsigned int __sync_val_compare_and_swap_8(
460 volatile void *ptr,
461 long long unsigned int oldval,
462 long long unsigned int newval) {
463 ShouldNotCallThis();
464 }
465 };
466 #endif // !_LP64
467
468 #ifndef PRODUCT
469 void os::verify_stack_alignment() {
470 }
471 #endif
472
473 int os::extra_bang_size_in_bytes() {
474 // Zero does not require an additional stack bang.
475 return 0;
476 }