1 /*
2 * Copyright (c) 2003, 2012, 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 ExtendedPC os::fetch_frame_from_context(void* ucVoid,
111 intptr_t** ret_sp,
112 intptr_t** ret_fp) {
113 ShouldNotCallThis();
114 return ExtendedPC();
115 }
116
117 frame os::fetch_frame_from_context(void* ucVoid) {
118 ShouldNotCallThis();
119 return frame();
120 }
121
122 extern "C" JNIEXPORT int
123 JVM_handle_bsd_signal(int sig,
124 siginfo_t* info,
125 void* ucVoid,
126 int abort_if_unrecognized) {
127 ucontext_t* uc = (ucontext_t*) ucVoid;
128
129 Thread* t = ThreadLocalStorage::get_thread_slow();
130
131 SignalHandlerMark shm(t);
132
133 // Note: it's not uncommon that JNI code uses signal/sigset to
134 // install then restore certain signal handler (e.g. to temporarily
135 // block SIGPIPE, or have a SIGILL handler when detecting CPU
136 // type). When that happens, JVM_handle_bsd_signal() might be
137 // invoked with junk info/ucVoid. To avoid unnecessary crash when
138 // libjsig is not preloaded, try handle signals that do not require
139 // siginfo/ucontext first.
140
141 if (sig == SIGPIPE || sig == SIGXFSZ) {
142 // allow chained handler to go first
143 if (os::Bsd::chained_handler(sig, info, ucVoid)) {
144 return true;
145 } else {
146 if (PrintMiscellaneous && (WizardMode || Verbose)) {
147 char buf[64];
148 warning("Ignoring %s - see bugs 4229104 or 646499219",
149 os::exception_name(sig, buf, sizeof(buf)));
150 }
151 return true;
152 }
153 }
154
155 JavaThread* thread = NULL;
156 VMThread* vmthread = NULL;
157 if (os::Bsd::signal_handlers_are_installed) {
158 if (t != NULL ){
159 if(t->is_Java_thread()) {
160 thread = (JavaThread*)t;
161 }
162 else if(t->is_VM_thread()){
163 vmthread = (VMThread *)t;
164 }
165 }
166 }
167
168 if (info != NULL && thread != NULL) {
169 // Handle ALL stack overflow variations here
170 if (sig == SIGSEGV || sig == SIGBUS) {
171 address addr = (address) info->si_addr;
172
173 // check if fault address is within thread stack
174 if (addr < thread->stack_base() &&
175 addr >= thread->stack_base() - thread->stack_size()) {
176 // stack overflow
177 if (thread->in_stack_yellow_zone(addr)) {
178 thread->disable_stack_yellow_zone();
179 ShouldNotCallThis();
180 }
181 else if (thread->in_stack_red_zone(addr)) {
182 thread->disable_stack_red_zone();
183 ShouldNotCallThis();
184 }
185 }
186 }
187
188 /*if (thread->thread_state() == _thread_in_Java) {
189 ShouldNotCallThis();
190 }
191 else*/ if (thread->thread_state() == _thread_in_vm &&
192 sig == SIGBUS && thread->doing_unsafe_access()) {
193 ShouldNotCallThis();
194 }
195
196 // jni_fast_Get<Primitive>Field can trap at certain pc's if a GC
197 // kicks in and the heap gets shrunk before the field access.
198 /*if (sig == SIGSEGV || sig == SIGBUS) {
199 address addr = JNI_FastGetField::find_slowcase_pc(pc);
200 if (addr != (address)-1) {
201 stub = addr;
202 }
203 }*/
204
205 // Check to see if we caught the safepoint code in the process
206 // of write protecting the memory serialization page. It write
207 // enables the page immediately after protecting it so we can
208 // just return to retry the write.
209 if ((sig == SIGSEGV || sig == SIGBUS) &&
210 os::is_memory_serialize_page(thread, (address) info->si_addr)) {
211 // Block current thread until permission is restored.
212 os::block_on_serialize_page_trap();
213 return true;
214 }
215 }
216
217 // signal-chaining
218 if (os::Bsd::chained_handler(sig, info, ucVoid)) {
219 return true;
220 }
221
222 if (!abort_if_unrecognized) {
223 // caller wants another chance, so give it to him
224 return false;
225 }
226
227 #ifndef PRODUCT
228 if (sig == SIGSEGV) {
229 fatal("\n#"
230 "\n# /--------------------\\"
231 "\n# | segmentation fault |"
232 "\n# \\---\\ /--------------/"
233 "\n# /"
234 "\n# [-] |\\_/| "
235 "\n# (+)=C |o o|__ "
236 "\n# | | =-*-=__\\ "
237 "\n# OOO c_c_(___)");
238 }
239 #endif // !PRODUCT
240
241 const char *fmt =
242 "caught unhandled signal " INT32_FORMAT " at address " PTR_FORMAT;
243 char buf[128];
244
245 sprintf(buf, fmt, sig, info->si_addr);
246 fatal(buf);
247 return false;
248 }
249
250 void os::Bsd::init_thread_fpu_state(void) {
251 // Nothing to do
252 }
253
254 bool os::is_allocatable(size_t bytes) {
255 #ifdef _LP64
256 return true;
257 #else
258 if (bytes < 2 * G) {
259 return true;
260 }
261
262 char* addr = reserve_memory(bytes, NULL);
263
264 if (addr != NULL) {
265 release_memory(addr, bytes);
266 }
267
268 return addr != NULL;
269 #endif // _LP64
270 }
271
272 ///////////////////////////////////////////////////////////////////////////////
273 // thread stack
274
275 size_t os::Bsd::min_stack_allowed = 64 * K;
276
277 bool os::Bsd::supports_variable_stack_size() {
278 return true;
279 }
280
281 size_t os::Bsd::default_stack_size(os::ThreadType thr_type) {
282 #ifdef _LP64
283 size_t s = (thr_type == os::compiler_thread ? 4 * M : 1 * M);
284 #else
285 size_t s = (thr_type == os::compiler_thread ? 2 * M : 512 * K);
286 #endif // _LP64
287 return s;
288 }
289
290 size_t os::Bsd::default_guard_size(os::ThreadType thr_type) {
291 // Only enable glibc guard pages for non-Java threads
292 // (Java threads have HotSpot guard pages)
293 return (thr_type == java_thread ? 0 : page_size());
294 }
295
296 static void current_stack_region(address *bottom, size_t *size) {
297 address stack_bottom;
298 address stack_top;
299 size_t stack_bytes;
300
301 #ifdef __APPLE__
302 pthread_t self = pthread_self();
303 stack_top = (address) pthread_get_stackaddr_np(self);
304 stack_bytes = pthread_get_stacksize_np(self);
305 stack_bottom = stack_top - stack_bytes;
306 #elif defined(__OpenBSD__)
307 stack_t ss;
308 int rslt = pthread_stackseg_np(pthread_self(), &ss);
309
310 if (rslt != 0)
311 fatal(err_msg("pthread_stackseg_np failed with err = " INT32_FORMAT,
312 rslt));
313
314 stack_top = (address) ss.ss_sp;
315 stack_bytes = ss.ss_size;
316 stack_bottom = stack_top - stack_bytes;
317 #else
318 pthread_attr_t attr;
319
320 int rslt = pthread_attr_init(&attr);
321
322 // JVM needs to know exact stack location, abort if it fails
323 if (rslt != 0)
324 fatal(err_msg("pthread_attr_init failed with err = " INT32_FORMAT, rslt));
325
326 rslt = pthread_attr_get_np(pthread_self(), &attr);
327
328 if (rslt != 0)
329 fatal(err_msg("pthread_attr_get_np failed with err = " INT32_FORMAT,
330 rslt));
331
332 if (pthread_attr_getstackaddr(&attr, (void **) &stack_bottom) != 0 ||
333 pthread_attr_getstacksize(&attr, &stack_bytes) != 0) {
334 fatal("Can not locate current stack attributes!");
335 }
336
337 pthread_attr_destroy(&attr);
338
339 stack_top = stack_bottom + stack_bytes;
340 #endif
341
342 assert(os::current_stack_pointer() >= stack_bottom, "should do");
343 assert(os::current_stack_pointer() < stack_top, "should do");
344
345 *bottom = stack_bottom;
346 *size = stack_top - stack_bottom;
347 }
348
349 address os::current_stack_base() {
350 address bottom;
351 size_t size;
352 current_stack_region(&bottom, &size);
353 return bottom + size;
354 }
355
356 size_t os::current_stack_size() {
357 // stack size includes normal stack and HotSpot guard pages
358 address bottom;
359 size_t size;
360 current_stack_region(&bottom, &size);
361 return size;
362 }
363
364 /////////////////////////////////////////////////////////////////////////////
365 // helper functions for fatal error handler
366
367 void os::print_context(outputStream* st, void* context) {
368 ShouldNotCallThis();
369 }
370
371 void os::print_register_info(outputStream *st, void *context) {
372 ShouldNotCallThis();
373 }
374
375 /////////////////////////////////////////////////////////////////////////////
376 // Stubs for things that would be in bsd_zero.s if it existed.
377 // You probably want to disassemble these monkeys to check they're ok.
378
379 extern "C" {
380 int SpinPause() {
381 return 1;
382 }
383
384 void _Copy_conjoint_jshorts_atomic(jshort* from, jshort* to, size_t count) {
385 if (from > to) {
386 jshort *end = from + count;
387 while (from < end)
388 *(to++) = *(from++);
389 }
390 else if (from < to) {
391 jshort *end = from;
392 from += count - 1;
393 to += count - 1;
394 while (from >= end)
395 *(to--) = *(from--);
396 }
397 }
398 void _Copy_conjoint_jints_atomic(jint* from, jint* to, size_t count) {
399 if (from > to) {
400 jint *end = from + count;
401 while (from < end)
402 *(to++) = *(from++);
403 }
404 else if (from < to) {
405 jint *end = from;
406 from += count - 1;
407 to += count - 1;
408 while (from >= end)
409 *(to--) = *(from--);
410 }
411 }
412 void _Copy_conjoint_jlongs_atomic(jlong* from, jlong* to, size_t count) {
413 if (from > to) {
414 jlong *end = from + count;
415 while (from < end)
416 os::atomic_copy64(from++, to++);
417 }
418 else if (from < to) {
419 jlong *end = from;
420 from += count - 1;
421 to += count - 1;
422 while (from >= end)
423 os::atomic_copy64(from--, to--);
424 }
425 }
426
427 void _Copy_arrayof_conjoint_bytes(HeapWord* from,
428 HeapWord* to,
429 size_t count) {
430 memmove(to, from, count);
431 }
432 void _Copy_arrayof_conjoint_jshorts(HeapWord* from,
433 HeapWord* to,
434 size_t count) {
435 memmove(to, from, count * 2);
436 }
437 void _Copy_arrayof_conjoint_jints(HeapWord* from,
438 HeapWord* to,
439 size_t count) {
440 memmove(to, from, count * 4);
441 }
442 void _Copy_arrayof_conjoint_jlongs(HeapWord* from,
443 HeapWord* to,
444 size_t count) {
445 memmove(to, from, count * 8);
446 }
447 };
448
449 /////////////////////////////////////////////////////////////////////////////
450 // Implementations of atomic operations not supported by processors.
451 // -- http://gcc.gnu.org/onlinedocs/gcc-4.2.1/gcc/Atomic-Builtins.html
452
453 #ifndef _LP64
454 extern "C" {
455 long long unsigned int __sync_val_compare_and_swap_8(
456 volatile void *ptr,
457 long long unsigned int oldval,
458 long long unsigned int newval) {
459 ShouldNotCallThis();
460 }
461 };
462 #endif // !_LP64
463
464 #ifndef PRODUCT
465 void os::verify_stack_alignment() {
466 }
467 #endif