Mercurial > hg > graal-compiler
annotate src/os_cpu/linux_x86/vm/os_linux_x86.cpp @ 13730:168976cae9ce
fix invalid MemoryPhiNodes at loop begins
author | Lukas Stadler <lukas.stadler@jku.at> |
---|---|
date | Wed, 22 Jan 2014 15:27:31 +0100 |
parents | cefad50507d8 |
children | d8041d695d19 |
rev | line source |
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0 | 1 /* |
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2 * Copyright (c) 1999, 2012, Oracle and/or its affiliates. All rights reserved. |
0 | 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 * | |
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19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
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20 * or visit www.oracle.com if you need additional information or have any |
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21 * questions. |
0 | 22 * |
23 */ | |
24 | |
1972 | 25 // no precompiled headers |
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26 #include "asm/macroAssembler.hpp" |
1972 | 27 #include "classfile/classLoader.hpp" |
28 #include "classfile/systemDictionary.hpp" | |
29 #include "classfile/vmSymbols.hpp" | |
30 #include "code/icBuffer.hpp" | |
31 #include "code/vtableStubs.hpp" | |
32 #include "interpreter/interpreter.hpp" | |
33 #include "jvm_linux.h" | |
34 #include "memory/allocation.inline.hpp" | |
35 #include "mutex_linux.inline.hpp" | |
36 #include "os_share_linux.hpp" | |
37 #include "prims/jniFastGetField.hpp" | |
38 #include "prims/jvm.h" | |
39 #include "prims/jvm_misc.hpp" | |
40 #include "runtime/arguments.hpp" | |
41 #include "runtime/extendedPC.hpp" | |
42 #include "runtime/frame.inline.hpp" | |
43 #include "runtime/interfaceSupport.hpp" | |
44 #include "runtime/java.hpp" | |
45 #include "runtime/javaCalls.hpp" | |
46 #include "runtime/mutexLocker.hpp" | |
47 #include "runtime/osThread.hpp" | |
48 #include "runtime/sharedRuntime.hpp" | |
49 #include "runtime/stubRoutines.hpp" | |
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50 #include "runtime/thread.inline.hpp" |
1972 | 51 #include "runtime/timer.hpp" |
52 #include "utilities/events.hpp" | |
53 #include "utilities/vmError.hpp" | |
0 | 54 |
55 // put OS-includes here | |
56 # include <sys/types.h> | |
57 # include <sys/mman.h> | |
58 # include <pthread.h> | |
59 # include <signal.h> | |
60 # include <errno.h> | |
61 # include <dlfcn.h> | |
62 # include <stdlib.h> | |
63 # include <stdio.h> | |
64 # include <unistd.h> | |
65 # include <sys/resource.h> | |
66 # include <pthread.h> | |
67 # include <sys/stat.h> | |
68 # include <sys/time.h> | |
69 # include <sys/utsname.h> | |
70 # include <sys/socket.h> | |
71 # include <sys/wait.h> | |
72 # include <pwd.h> | |
73 # include <poll.h> | |
74 # include <ucontext.h> | |
75 # include <fpu_control.h> | |
76 | |
77 #ifdef AMD64 | |
78 #define REG_SP REG_RSP | |
79 #define REG_PC REG_RIP | |
80 #define REG_FP REG_RBP | |
81 #define SPELL_REG_SP "rsp" | |
82 #define SPELL_REG_FP "rbp" | |
83 #else | |
84 #define REG_SP REG_UESP | |
85 #define REG_PC REG_EIP | |
86 #define REG_FP REG_EBP | |
87 #define SPELL_REG_SP "esp" | |
88 #define SPELL_REG_FP "ebp" | |
89 #endif // AMD64 | |
90 | |
91 address os::current_stack_pointer() { | |
50
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92 #ifdef SPARC_WORKS |
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93 register void *esp; |
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94 __asm__("mov %%"SPELL_REG_SP", %0":"=r"(esp)); |
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95 return (address) ((char*)esp + sizeof(long)*2); |
10398 | 96 #elif defined(__clang__) |
97 intptr_t* esp; | |
98 __asm__ __volatile__ ("mov %%"SPELL_REG_SP", %0":"=r"(esp):); | |
99 return (address) esp; | |
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100 #else |
0 | 101 register void *esp __asm__ (SPELL_REG_SP); |
102 return (address) esp; | |
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103 #endif |
0 | 104 } |
105 | |
106 char* os::non_memory_address_word() { | |
107 // Must never look like an address returned by reserve_memory, | |
108 // even in its subfields (as defined by the CPU immediate fields, | |
109 // if the CPU splits constants across multiple instructions). | |
110 | |
111 return (char*) -1; | |
112 } | |
113 | |
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114 void os::initialize_thread(Thread* thr) { |
0 | 115 // Nothing to do. |
116 } | |
117 | |
118 address os::Linux::ucontext_get_pc(ucontext_t * uc) { | |
119 return (address)uc->uc_mcontext.gregs[REG_PC]; | |
120 } | |
121 | |
122 intptr_t* os::Linux::ucontext_get_sp(ucontext_t * uc) { | |
123 return (intptr_t*)uc->uc_mcontext.gregs[REG_SP]; | |
124 } | |
125 | |
126 intptr_t* os::Linux::ucontext_get_fp(ucontext_t * uc) { | |
127 return (intptr_t*)uc->uc_mcontext.gregs[REG_FP]; | |
128 } | |
129 | |
130 // For Forte Analyzer AsyncGetCallTrace profiling support - thread | |
131 // is currently interrupted by SIGPROF. | |
132 // os::Solaris::fetch_frame_from_ucontext() tries to skip nested signal | |
133 // frames. Currently we don't do that on Linux, so it's the same as | |
134 // os::fetch_frame_from_context(). | |
135 ExtendedPC os::Linux::fetch_frame_from_ucontext(Thread* thread, | |
136 ucontext_t* uc, intptr_t** ret_sp, intptr_t** ret_fp) { | |
137 | |
138 assert(thread != NULL, "just checking"); | |
139 assert(ret_sp != NULL, "just checking"); | |
140 assert(ret_fp != NULL, "just checking"); | |
141 | |
142 return os::fetch_frame_from_context(uc, ret_sp, ret_fp); | |
143 } | |
144 | |
145 ExtendedPC os::fetch_frame_from_context(void* ucVoid, | |
146 intptr_t** ret_sp, intptr_t** ret_fp) { | |
147 | |
148 ExtendedPC epc; | |
149 ucontext_t* uc = (ucontext_t*)ucVoid; | |
150 | |
151 if (uc != NULL) { | |
152 epc = ExtendedPC(os::Linux::ucontext_get_pc(uc)); | |
153 if (ret_sp) *ret_sp = os::Linux::ucontext_get_sp(uc); | |
154 if (ret_fp) *ret_fp = os::Linux::ucontext_get_fp(uc); | |
155 } else { | |
156 // construct empty ExtendedPC for return value checking | |
157 epc = ExtendedPC(NULL); | |
158 if (ret_sp) *ret_sp = (intptr_t *)NULL; | |
159 if (ret_fp) *ret_fp = (intptr_t *)NULL; | |
160 } | |
161 | |
162 return epc; | |
163 } | |
164 | |
165 frame os::fetch_frame_from_context(void* ucVoid) { | |
166 intptr_t* sp; | |
167 intptr_t* fp; | |
168 ExtendedPC epc = fetch_frame_from_context(ucVoid, &sp, &fp); | |
169 return frame(sp, fp, epc.pc()); | |
170 } | |
171 | |
172 // By default, gcc always save frame pointer (%ebp/%rbp) on stack. It may get | |
173 // turned off by -fomit-frame-pointer, | |
174 frame os::get_sender_for_C_frame(frame* fr) { | |
175 return frame(fr->sender_sp(), fr->link(), fr->sender_pc()); | |
176 } | |
177 | |
178 intptr_t* _get_previous_fp() { | |
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179 #ifdef SPARC_WORKS |
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180 register intptr_t **ebp; |
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181 __asm__("mov %%"SPELL_REG_FP", %0":"=r"(ebp)); |
10398 | 182 #elif defined(__clang__) |
183 intptr_t **ebp; | |
184 __asm__ __volatile__ ("mov %%"SPELL_REG_FP", %0":"=r"(ebp):); | |
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185 #else |
0 | 186 register intptr_t **ebp __asm__ (SPELL_REG_FP); |
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187 #endif |
0 | 188 return (intptr_t*) *ebp; // we want what it points to. |
189 } | |
190 | |
191 | |
192 frame os::current_frame() { | |
193 intptr_t* fp = _get_previous_fp(); | |
194 frame myframe((intptr_t*)os::current_stack_pointer(), | |
195 (intptr_t*)fp, | |
196 CAST_FROM_FN_PTR(address, os::current_frame)); | |
197 if (os::is_first_C_frame(&myframe)) { | |
198 // stack is not walkable | |
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199 return frame(); |
0 | 200 } else { |
201 return os::get_sender_for_C_frame(&myframe); | |
202 } | |
203 } | |
204 | |
205 // Utility functions | |
206 | |
207 // From IA32 System Programming Guide | |
208 enum { | |
209 trap_page_fault = 0xE | |
210 }; | |
211 | |
2191 | 212 extern "C" JNIEXPORT int |
0 | 213 JVM_handle_linux_signal(int sig, |
214 siginfo_t* info, | |
215 void* ucVoid, | |
216 int abort_if_unrecognized) { | |
217 ucontext_t* uc = (ucontext_t*) ucVoid; | |
218 | |
219 Thread* t = ThreadLocalStorage::get_thread_slow(); | |
220 | |
11151 | 221 // Must do this before SignalHandlerMark, if crash protection installed we will longjmp away |
222 // (no destructors can be run) | |
223 os::WatcherThreadCrashProtection::check_crash_protection(sig, t); | |
224 | |
0 | 225 SignalHandlerMark shm(t); |
226 | |
227 // Note: it's not uncommon that JNI code uses signal/sigset to install | |
228 // then restore certain signal handler (e.g. to temporarily block SIGPIPE, | |
229 // or have a SIGILL handler when detecting CPU type). When that happens, | |
230 // JVM_handle_linux_signal() might be invoked with junk info/ucVoid. To | |
231 // avoid unnecessary crash when libjsig is not preloaded, try handle signals | |
232 // that do not require siginfo/ucontext first. | |
233 | |
234 if (sig == SIGPIPE || sig == SIGXFSZ) { | |
235 // allow chained handler to go first | |
236 if (os::Linux::chained_handler(sig, info, ucVoid)) { | |
237 return true; | |
238 } else { | |
239 if (PrintMiscellaneous && (WizardMode || Verbose)) { | |
240 char buf[64]; | |
241 warning("Ignoring %s - see bugs 4229104 or 646499219", | |
242 os::exception_name(sig, buf, sizeof(buf))); | |
243 } | |
244 return true; | |
245 } | |
246 } | |
247 | |
248 JavaThread* thread = NULL; | |
249 VMThread* vmthread = NULL; | |
250 if (os::Linux::signal_handlers_are_installed) { | |
251 if (t != NULL ){ | |
252 if(t->is_Java_thread()) { | |
253 thread = (JavaThread*)t; | |
254 } | |
255 else if(t->is_VM_thread()){ | |
256 vmthread = (VMThread *)t; | |
257 } | |
258 } | |
259 } | |
260 /* | |
261 NOTE: does not seem to work on linux. | |
262 if (info == NULL || info->si_code <= 0 || info->si_code == SI_NOINFO) { | |
263 // can't decode this kind of signal | |
264 info = NULL; | |
265 } else { | |
266 assert(sig == info->si_signo, "bad siginfo"); | |
267 } | |
268 */ | |
269 // decide if this trap can be handled by a stub | |
270 address stub = NULL; | |
271 | |
272 address pc = NULL; | |
273 | |
274 //%note os_trap_1 | |
275 if (info != NULL && uc != NULL && thread != NULL) { | |
276 pc = (address) os::Linux::ucontext_get_pc(uc); | |
277 | |
11127 | 278 if (StubRoutines::is_safefetch_fault(pc)) { |
279 uc->uc_mcontext.gregs[REG_PC] = intptr_t(StubRoutines::continuation_for_safefetch_fault(pc)); | |
280 return 1; | |
0 | 281 } |
282 | |
11029 | 283 #ifndef AMD64 |
284 // Halt if SI_KERNEL before more crashes get misdiagnosed as Java bugs | |
285 // This can happen in any running code (currently more frequently in | |
286 // interpreter code but has been seen in compiled code) | |
287 if (sig == SIGSEGV && info->si_addr == 0 && info->si_code == SI_KERNEL) { | |
288 fatal("An irrecoverable SI_KERNEL SIGSEGV has occurred due " | |
289 "to unstable signal handling in this distribution."); | |
290 } | |
291 #endif // AMD64 | |
292 | |
0 | 293 // Handle ALL stack overflow variations here |
294 if (sig == SIGSEGV) { | |
295 address addr = (address) info->si_addr; | |
296 | |
297 // check if fault address is within thread stack | |
298 if (addr < thread->stack_base() && | |
299 addr >= thread->stack_base() - thread->stack_size()) { | |
300 // stack overflow | |
301 if (thread->in_stack_yellow_zone(addr)) { | |
302 thread->disable_stack_yellow_zone(); | |
303 if (thread->thread_state() == _thread_in_Java) { | |
304 // Throw a stack overflow exception. Guard pages will be reenabled | |
305 // while unwinding the stack. | |
306 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::STACK_OVERFLOW); | |
307 } else { | |
308 // Thread was in the vm or native code. Return and try to finish. | |
309 return 1; | |
310 } | |
311 } else if (thread->in_stack_red_zone(addr)) { | |
312 // Fatal red zone violation. Disable the guard pages and fall through | |
313 // to handle_unexpected_exception way down below. | |
314 thread->disable_stack_red_zone(); | |
315 tty->print_raw_cr("An irrecoverable stack overflow has occurred."); | |
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316 |
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317 // This is a likely cause, but hard to verify. Let's just print |
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318 // it as a hint. |
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319 tty->print_raw_cr("Please check if any of your loaded .so files has " |
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320 "enabled executable stack (see man page execstack(8))"); |
0 | 321 } else { |
322 // Accessing stack address below sp may cause SEGV if current | |
323 // thread has MAP_GROWSDOWN stack. This should only happen when | |
324 // current thread was created by user code with MAP_GROWSDOWN flag | |
325 // and then attached to VM. See notes in os_linux.cpp. | |
326 if (thread->osthread()->expanding_stack() == 0) { | |
327 thread->osthread()->set_expanding_stack(); | |
328 if (os::Linux::manually_expand_stack(thread, addr)) { | |
329 thread->osthread()->clear_expanding_stack(); | |
330 return 1; | |
331 } | |
332 thread->osthread()->clear_expanding_stack(); | |
333 } else { | |
334 fatal("recursive segv. expanding stack."); | |
335 } | |
336 } | |
337 } | |
338 } | |
339 | |
340 if (thread->thread_state() == _thread_in_Java) { | |
341 // Java thread running in Java code => find exception handler if any | |
342 // a fault inside compiled code, the interpreter, or a stub | |
343 | |
344 if (sig == SIGSEGV && os::is_poll_address((address)info->si_addr)) { | |
345 stub = SharedRuntime::get_poll_stub(pc); | |
346 } else if (sig == SIGBUS /* && info->si_code == BUS_OBJERR */) { | |
347 // BugId 4454115: A read from a MappedByteBuffer can fault | |
348 // here if the underlying file has been truncated. | |
349 // Do not crash the VM in such a case. | |
350 CodeBlob* cb = CodeCache::find_blob_unsafe(pc); | |
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351 nmethod* nm = (cb != NULL && cb->is_nmethod()) ? (nmethod*)cb : NULL; |
0 | 352 if (nm != NULL && nm->has_unsafe_access()) { |
353 stub = StubRoutines::handler_for_unsafe_access(); | |
354 } | |
355 } | |
356 else | |
357 | |
358 #ifdef AMD64 | |
359 if (sig == SIGFPE && | |
360 (info->si_code == FPE_INTDIV || info->si_code == FPE_FLTDIV)) { | |
361 stub = | |
362 SharedRuntime:: | |
363 continuation_for_implicit_exception(thread, | |
364 pc, | |
365 SharedRuntime:: | |
366 IMPLICIT_DIVIDE_BY_ZERO); | |
367 #else | |
368 if (sig == SIGFPE /* && info->si_code == FPE_INTDIV */) { | |
369 // HACK: si_code does not work on linux 2.2.12-20!!! | |
370 int op = pc[0]; | |
371 if (op == 0xDB) { | |
372 // FIST | |
373 // TODO: The encoding of D2I in i486.ad can cause an exception | |
374 // prior to the fist instruction if there was an invalid operation | |
375 // pending. We want to dismiss that exception. From the win_32 | |
376 // side it also seems that if it really was the fist causing | |
377 // the exception that we do the d2i by hand with different | |
378 // rounding. Seems kind of weird. | |
379 // NOTE: that we take the exception at the NEXT floating point instruction. | |
380 assert(pc[0] == 0xDB, "not a FIST opcode"); | |
381 assert(pc[1] == 0x14, "not a FIST opcode"); | |
382 assert(pc[2] == 0x24, "not a FIST opcode"); | |
383 return true; | |
384 } else if (op == 0xF7) { | |
385 // IDIV | |
386 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_DIVIDE_BY_ZERO); | |
387 } else { | |
388 // TODO: handle more cases if we are using other x86 instructions | |
389 // that can generate SIGFPE signal on linux. | |
390 tty->print_cr("unknown opcode 0x%X with SIGFPE.", op); | |
391 fatal("please update this code."); | |
392 } | |
393 #endif // AMD64 | |
394 } else if (sig == SIGSEGV && | |
395 !MacroAssembler::needs_explicit_null_check((intptr_t)info->si_addr)) { | |
396 // Determination of interpreter/vtable stub/compiled code null exception | |
397 stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_NULL); | |
398 } | |
399 } else if (thread->thread_state() == _thread_in_vm && | |
400 sig == SIGBUS && /* info->si_code == BUS_OBJERR && */ | |
401 thread->doing_unsafe_access()) { | |
402 stub = StubRoutines::handler_for_unsafe_access(); | |
403 } | |
404 | |
405 // jni_fast_Get<Primitive>Field can trap at certain pc's if a GC kicks in | |
406 // and the heap gets shrunk before the field access. | |
407 if ((sig == SIGSEGV) || (sig == SIGBUS)) { | |
408 address addr = JNI_FastGetField::find_slowcase_pc(pc); | |
409 if (addr != (address)-1) { | |
410 stub = addr; | |
411 } | |
412 } | |
413 | |
414 // Check to see if we caught the safepoint code in the | |
415 // process of write protecting the memory serialization page. | |
416 // It write enables the page immediately after protecting it | |
417 // so we can just return to retry the write. | |
418 if ((sig == SIGSEGV) && | |
419 os::is_memory_serialize_page(thread, (address) info->si_addr)) { | |
420 // Block current thread until the memory serialize page permission restored. | |
421 os::block_on_serialize_page_trap(); | |
422 return true; | |
423 } | |
424 } | |
425 | |
426 #ifndef AMD64 | |
427 // Execution protection violation | |
428 // | |
429 // This should be kept as the last step in the triage. We don't | |
430 // have a dedicated trap number for a no-execute fault, so be | |
431 // conservative and allow other handlers the first shot. | |
432 // | |
433 // Note: We don't test that info->si_code == SEGV_ACCERR here. | |
434 // this si_code is so generic that it is almost meaningless; and | |
435 // the si_code for this condition may change in the future. | |
436 // Furthermore, a false-positive should be harmless. | |
437 if (UnguardOnExecutionViolation > 0 && | |
438 (sig == SIGSEGV || sig == SIGBUS) && | |
439 uc->uc_mcontext.gregs[REG_TRAPNO] == trap_page_fault) { | |
440 int page_size = os::vm_page_size(); | |
441 address addr = (address) info->si_addr; | |
442 address pc = os::Linux::ucontext_get_pc(uc); | |
443 // Make sure the pc and the faulting address are sane. | |
444 // | |
445 // If an instruction spans a page boundary, and the page containing | |
446 // the beginning of the instruction is executable but the following | |
447 // page is not, the pc and the faulting address might be slightly | |
448 // different - we still want to unguard the 2nd page in this case. | |
449 // | |
450 // 15 bytes seems to be a (very) safe value for max instruction size. | |
451 bool pc_is_near_addr = | |
452 (pointer_delta((void*) addr, (void*) pc, sizeof(char)) < 15); | |
453 bool instr_spans_page_boundary = | |
454 (align_size_down((intptr_t) pc ^ (intptr_t) addr, | |
455 (intptr_t) page_size) > 0); | |
456 | |
457 if (pc == addr || (pc_is_near_addr && instr_spans_page_boundary)) { | |
458 static volatile address last_addr = | |
459 (address) os::non_memory_address_word(); | |
460 | |
461 // In conservative mode, don't unguard unless the address is in the VM | |
462 if (addr != last_addr && | |
463 (UnguardOnExecutionViolation > 1 || os::address_is_in_vm(addr))) { | |
464 | |
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465 // Set memory to RWX and retry |
0 | 466 address page_start = |
467 (address) align_size_down((intptr_t) addr, (intptr_t) page_size); | |
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468 bool res = os::protect_memory((char*) page_start, page_size, |
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469 os::MEM_PROT_RWX); |
0 | 470 |
471 if (PrintMiscellaneous && Verbose) { | |
472 char buf[256]; | |
473 jio_snprintf(buf, sizeof(buf), "Execution protection violation " | |
474 "at " INTPTR_FORMAT | |
475 ", unguarding " INTPTR_FORMAT ": %s, errno=%d", addr, | |
476 page_start, (res ? "success" : "failed"), errno); | |
477 tty->print_raw_cr(buf); | |
478 } | |
479 stub = pc; | |
480 | |
481 // Set last_addr so if we fault again at the same address, we don't end | |
482 // up in an endless loop. | |
483 // | |
484 // There are two potential complications here. Two threads trapping at | |
485 // the same address at the same time could cause one of the threads to | |
486 // think it already unguarded, and abort the VM. Likely very rare. | |
487 // | |
488 // The other race involves two threads alternately trapping at | |
489 // different addresses and failing to unguard the page, resulting in | |
490 // an endless loop. This condition is probably even more unlikely than | |
491 // the first. | |
492 // | |
493 // Although both cases could be avoided by using locks or thread local | |
494 // last_addr, these solutions are unnecessary complication: this | |
495 // handler is a best-effort safety net, not a complete solution. It is | |
496 // disabled by default and should only be used as a workaround in case | |
497 // we missed any no-execute-unsafe VM code. | |
498 | |
499 last_addr = addr; | |
500 } | |
501 } | |
502 } | |
503 #endif // !AMD64 | |
504 | |
505 if (stub != NULL) { | |
506 // save all thread context in case we need to restore it | |
507 if (thread != NULL) thread->set_saved_exception_pc(pc); | |
508 | |
509 uc->uc_mcontext.gregs[REG_PC] = (greg_t)stub; | |
510 return true; | |
511 } | |
512 | |
513 // signal-chaining | |
514 if (os::Linux::chained_handler(sig, info, ucVoid)) { | |
515 return true; | |
516 } | |
517 | |
518 if (!abort_if_unrecognized) { | |
519 // caller wants another chance, so give it to him | |
520 return false; | |
521 } | |
522 | |
523 if (pc == NULL && uc != NULL) { | |
524 pc = os::Linux::ucontext_get_pc(uc); | |
525 } | |
526 | |
527 // unmask current signal | |
528 sigset_t newset; | |
529 sigemptyset(&newset); | |
530 sigaddset(&newset, sig); | |
531 sigprocmask(SIG_UNBLOCK, &newset, NULL); | |
532 | |
533 VMError err(t, sig, pc, info, ucVoid); | |
534 err.report_and_die(); | |
535 | |
536 ShouldNotReachHere(); | |
537 } | |
538 | |
539 void os::Linux::init_thread_fpu_state(void) { | |
540 #ifndef AMD64 | |
541 // set fpu to 53 bit precision | |
542 set_fpu_control_word(0x27f); | |
543 #endif // !AMD64 | |
544 } | |
545 | |
546 int os::Linux::get_fpu_control_word(void) { | |
547 #ifdef AMD64 | |
548 return 0; | |
549 #else | |
550 int fpu_control; | |
551 _FPU_GETCW(fpu_control); | |
552 return fpu_control & 0xffff; | |
553 #endif // AMD64 | |
554 } | |
555 | |
556 void os::Linux::set_fpu_control_word(int fpu_control) { | |
557 #ifndef AMD64 | |
558 _FPU_SETCW(fpu_control); | |
559 #endif // !AMD64 | |
560 } | |
561 | |
562 // Check that the linux kernel version is 2.4 or higher since earlier | |
563 // versions do not support SSE without patches. | |
564 bool os::supports_sse() { | |
565 #ifdef AMD64 | |
566 return true; | |
567 #else | |
568 struct utsname uts; | |
569 if( uname(&uts) != 0 ) return false; // uname fails? | |
570 char *minor_string; | |
571 int major = strtol(uts.release,&minor_string,10); | |
572 int minor = strtol(minor_string+1,NULL,10); | |
573 bool result = (major > 2 || (major==2 && minor >= 4)); | |
574 #ifndef PRODUCT | |
575 if (PrintMiscellaneous && Verbose) { | |
576 tty->print("OS version is %d.%d, which %s support SSE/SSE2\n", | |
577 major,minor, result ? "DOES" : "does NOT"); | |
578 } | |
579 #endif | |
580 return result; | |
581 #endif // AMD64 | |
582 } | |
583 | |
584 bool os::is_allocatable(size_t bytes) { | |
585 #ifdef AMD64 | |
586 // unused on amd64? | |
587 return true; | |
588 #else | |
589 | |
590 if (bytes < 2 * G) { | |
591 return true; | |
592 } | |
593 | |
594 char* addr = reserve_memory(bytes, NULL); | |
595 | |
596 if (addr != NULL) { | |
597 release_memory(addr, bytes); | |
598 } | |
599 | |
600 return addr != NULL; | |
601 #endif // AMD64 | |
602 } | |
603 | |
604 //////////////////////////////////////////////////////////////////////////////// | |
605 // thread stack | |
606 | |
607 #ifdef AMD64 | |
608 size_t os::Linux::min_stack_allowed = 64 * K; | |
609 | |
610 // amd64: pthread on amd64 is always in floating stack mode | |
611 bool os::Linux::supports_variable_stack_size() { return true; } | |
612 #else | |
613 size_t os::Linux::min_stack_allowed = (48 DEBUG_ONLY(+4))*K; | |
614 | |
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615 #ifdef __GNUC__ |
0 | 616 #define GET_GS() ({int gs; __asm__ volatile("movw %%gs, %w0":"=q"(gs)); gs&0xffff;}) |
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617 #endif |
0 | 618 |
619 // Test if pthread library can support variable thread stack size. LinuxThreads | |
620 // in fixed stack mode allocates 2M fixed slot for each thread. LinuxThreads | |
621 // in floating stack mode and NPTL support variable stack size. | |
622 bool os::Linux::supports_variable_stack_size() { | |
623 if (os::Linux::is_NPTL()) { | |
624 // NPTL, yes | |
625 return true; | |
626 | |
627 } else { | |
628 // Note: We can't control default stack size when creating a thread. | |
629 // If we use non-default stack size (pthread_attr_setstacksize), both | |
630 // floating stack and non-floating stack LinuxThreads will return the | |
631 // same value. This makes it impossible to implement this function by | |
632 // detecting thread stack size directly. | |
633 // | |
634 // An alternative approach is to check %gs. Fixed-stack LinuxThreads | |
635 // do not use %gs, so its value is 0. Floating-stack LinuxThreads use | |
636 // %gs (either as LDT selector or GDT selector, depending on kernel) | |
637 // to access thread specific data. | |
638 // | |
639 // Note that %gs is a reserved glibc register since early 2001, so | |
640 // applications are not allowed to change its value (Ulrich Drepper from | |
641 // Redhat confirmed that all known offenders have been modified to use | |
642 // either %fs or TSD). In the worst case scenario, when VM is embedded in | |
643 // a native application that plays with %gs, we might see non-zero %gs | |
644 // even LinuxThreads is running in fixed stack mode. As the result, we'll | |
645 // return true and skip _thread_safety_check(), so we may not be able to | |
646 // detect stack-heap collisions. But otherwise it's harmless. | |
647 // | |
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648 #ifdef __GNUC__ |
0 | 649 return (GET_GS() != 0); |
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650 #else |
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651 return false; |
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652 #endif |
0 | 653 } |
654 } | |
655 #endif // AMD64 | |
656 | |
657 // return default stack size for thr_type | |
658 size_t os::Linux::default_stack_size(os::ThreadType thr_type) { | |
659 // default stack size (compiler thread needs larger stack) | |
660 #ifdef AMD64 | |
661 size_t s = (thr_type == os::compiler_thread ? 4 * M : 1 * M); | |
662 #else | |
663 size_t s = (thr_type == os::compiler_thread ? 2 * M : 512 * K); | |
664 #endif // AMD64 | |
665 return s; | |
666 } | |
667 | |
668 size_t os::Linux::default_guard_size(os::ThreadType thr_type) { | |
669 // Creating guard page is very expensive. Java thread has HotSpot | |
670 // guard page, only enable glibc guard page for non-Java threads. | |
671 return (thr_type == java_thread ? 0 : page_size()); | |
672 } | |
673 | |
674 // Java thread: | |
675 // | |
676 // Low memory addresses | |
677 // +------------------------+ | |
678 // | |\ JavaThread created by VM does not have glibc | |
679 // | glibc guard page | - guard, attached Java thread usually has | |
680 // | |/ 1 page glibc guard. | |
681 // P1 +------------------------+ Thread::stack_base() - Thread::stack_size() | |
682 // | |\ | |
683 // | HotSpot Guard Pages | - red and yellow pages | |
684 // | |/ | |
685 // +------------------------+ JavaThread::stack_yellow_zone_base() | |
686 // | |\ | |
687 // | Normal Stack | - | |
688 // | |/ | |
689 // P2 +------------------------+ Thread::stack_base() | |
690 // | |
691 // Non-Java thread: | |
692 // | |
693 // Low memory addresses | |
694 // +------------------------+ | |
695 // | |\ | |
696 // | glibc guard page | - usually 1 page | |
697 // | |/ | |
698 // P1 +------------------------+ Thread::stack_base() - Thread::stack_size() | |
699 // | |\ | |
700 // | Normal Stack | - | |
701 // | |/ | |
702 // P2 +------------------------+ Thread::stack_base() | |
703 // | |
704 // ** P1 (aka bottom) and size ( P2 = P1 - size) are the address and stack size returned from | |
705 // pthread_attr_getstack() | |
706 | |
707 static void current_stack_region(address * bottom, size_t * size) { | |
708 if (os::Linux::is_initial_thread()) { | |
709 // initial thread needs special handling because pthread_getattr_np() | |
710 // may return bogus value. | |
711 *bottom = os::Linux::initial_thread_stack_bottom(); | |
712 *size = os::Linux::initial_thread_stack_size(); | |
713 } else { | |
714 pthread_attr_t attr; | |
715 | |
716 int rslt = pthread_getattr_np(pthread_self(), &attr); | |
717 | |
718 // JVM needs to know exact stack location, abort if it fails | |
719 if (rslt != 0) { | |
720 if (rslt == ENOMEM) { | |
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721 vm_exit_out_of_memory(0, OOM_MMAP_ERROR, "pthread_getattr_np"); |
0 | 722 } else { |
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723 fatal(err_msg("pthread_getattr_np failed with errno = %d", rslt)); |
0 | 724 } |
725 } | |
726 | |
727 if (pthread_attr_getstack(&attr, (void **)bottom, size) != 0) { | |
728 fatal("Can not locate current stack attributes!"); | |
729 } | |
730 | |
731 pthread_attr_destroy(&attr); | |
732 | |
733 } | |
734 assert(os::current_stack_pointer() >= *bottom && | |
735 os::current_stack_pointer() < *bottom + *size, "just checking"); | |
736 } | |
737 | |
738 address os::current_stack_base() { | |
739 address bottom; | |
740 size_t size; | |
741 current_stack_region(&bottom, &size); | |
742 return (bottom + size); | |
743 } | |
744 | |
745 size_t os::current_stack_size() { | |
746 // stack size includes normal stack and HotSpot guard pages | |
747 address bottom; | |
748 size_t size; | |
749 current_stack_region(&bottom, &size); | |
750 return size; | |
751 } | |
752 | |
753 ///////////////////////////////////////////////////////////////////////////// | |
754 // helper functions for fatal error handler | |
755 | |
756 void os::print_context(outputStream *st, void *context) { | |
757 if (context == NULL) return; | |
758 | |
759 ucontext_t *uc = (ucontext_t*)context; | |
760 st->print_cr("Registers:"); | |
761 #ifdef AMD64 | |
762 st->print( "RAX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RAX]); | |
763 st->print(", RBX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RBX]); | |
764 st->print(", RCX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RCX]); | |
765 st->print(", RDX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RDX]); | |
766 st->cr(); | |
767 st->print( "RSP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RSP]); | |
768 st->print(", RBP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RBP]); | |
769 st->print(", RSI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RSI]); | |
770 st->print(", RDI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RDI]); | |
771 st->cr(); | |
772 st->print( "R8 =" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R8]); | |
773 st->print(", R9 =" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R9]); | |
774 st->print(", R10=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R10]); | |
775 st->print(", R11=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R11]); | |
776 st->cr(); | |
777 st->print( "R12=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R12]); | |
778 st->print(", R13=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R13]); | |
779 st->print(", R14=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R14]); | |
780 st->print(", R15=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_R15]); | |
781 st->cr(); | |
782 st->print( "RIP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_RIP]); | |
1907 | 783 st->print(", EFLAGS=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_EFL]); |
0 | 784 st->print(", CSGSFS=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_CSGSFS]); |
785 st->print(", ERR=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_ERR]); | |
786 st->cr(); | |
787 st->print(" TRAPNO=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_TRAPNO]); | |
788 #else | |
789 st->print( "EAX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_EAX]); | |
790 st->print(", EBX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_EBX]); | |
791 st->print(", ECX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_ECX]); | |
792 st->print(", EDX=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_EDX]); | |
793 st->cr(); | |
794 st->print( "ESP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_UESP]); | |
795 st->print(", EBP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_EBP]); | |
796 st->print(", ESI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_ESI]); | |
797 st->print(", EDI=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_EDI]); | |
798 st->cr(); | |
799 st->print( "EIP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_EIP]); | |
1907 | 800 st->print(", EFLAGS=" INTPTR_FORMAT, uc->uc_mcontext.gregs[REG_EFL]); |
0 | 801 st->print(", CR2=" INTPTR_FORMAT, uc->uc_mcontext.cr2); |
802 #endif // AMD64 | |
803 st->cr(); | |
804 st->cr(); | |
805 | |
806 intptr_t *sp = (intptr_t *)os::Linux::ucontext_get_sp(uc); | |
807 st->print_cr("Top of Stack: (sp=" PTR_FORMAT ")", sp); | |
808 print_hex_dump(st, (address)sp, (address)(sp + 8*sizeof(intptr_t)), sizeof(intptr_t)); | |
809 st->cr(); | |
810 | |
811 // Note: it may be unsafe to inspect memory near pc. For example, pc may | |
812 // point to garbage if entry point in an nmethod is corrupted. Leave | |
813 // this at the end, and hope for the best. | |
814 address pc = os::Linux::ucontext_get_pc(uc); | |
815 st->print_cr("Instructions: (pc=" PTR_FORMAT ")", pc); | |
1907 | 816 print_hex_dump(st, pc - 32, pc + 32, sizeof(char)); |
817 } | |
818 | |
819 void os::print_register_info(outputStream *st, void *context) { | |
820 if (context == NULL) return; | |
821 | |
822 ucontext_t *uc = (ucontext_t*)context; | |
823 | |
824 st->print_cr("Register to memory mapping:"); | |
825 st->cr(); | |
826 | |
827 // this is horrendously verbose but the layout of the registers in the | |
828 // context does not match how we defined our abstract Register set, so | |
829 // we can't just iterate through the gregs area | |
830 | |
831 // this is only for the "general purpose" registers | |
832 | |
833 #ifdef AMD64 | |
834 st->print("RAX="); print_location(st, uc->uc_mcontext.gregs[REG_RAX]); | |
835 st->print("RBX="); print_location(st, uc->uc_mcontext.gregs[REG_RBX]); | |
836 st->print("RCX="); print_location(st, uc->uc_mcontext.gregs[REG_RCX]); | |
837 st->print("RDX="); print_location(st, uc->uc_mcontext.gregs[REG_RDX]); | |
838 st->print("RSP="); print_location(st, uc->uc_mcontext.gregs[REG_RSP]); | |
839 st->print("RBP="); print_location(st, uc->uc_mcontext.gregs[REG_RBP]); | |
840 st->print("RSI="); print_location(st, uc->uc_mcontext.gregs[REG_RSI]); | |
841 st->print("RDI="); print_location(st, uc->uc_mcontext.gregs[REG_RDI]); | |
842 st->print("R8 ="); print_location(st, uc->uc_mcontext.gregs[REG_R8]); | |
843 st->print("R9 ="); print_location(st, uc->uc_mcontext.gregs[REG_R9]); | |
844 st->print("R10="); print_location(st, uc->uc_mcontext.gregs[REG_R10]); | |
845 st->print("R11="); print_location(st, uc->uc_mcontext.gregs[REG_R11]); | |
846 st->print("R12="); print_location(st, uc->uc_mcontext.gregs[REG_R12]); | |
847 st->print("R13="); print_location(st, uc->uc_mcontext.gregs[REG_R13]); | |
848 st->print("R14="); print_location(st, uc->uc_mcontext.gregs[REG_R14]); | |
849 st->print("R15="); print_location(st, uc->uc_mcontext.gregs[REG_R15]); | |
850 #else | |
851 st->print("EAX="); print_location(st, uc->uc_mcontext.gregs[REG_EAX]); | |
852 st->print("EBX="); print_location(st, uc->uc_mcontext.gregs[REG_EBX]); | |
853 st->print("ECX="); print_location(st, uc->uc_mcontext.gregs[REG_ECX]); | |
854 st->print("EDX="); print_location(st, uc->uc_mcontext.gregs[REG_EDX]); | |
855 st->print("ESP="); print_location(st, uc->uc_mcontext.gregs[REG_ESP]); | |
856 st->print("EBP="); print_location(st, uc->uc_mcontext.gregs[REG_EBP]); | |
857 st->print("ESI="); print_location(st, uc->uc_mcontext.gregs[REG_ESI]); | |
858 st->print("EDI="); print_location(st, uc->uc_mcontext.gregs[REG_EDI]); | |
859 #endif // AMD64 | |
860 | |
861 st->cr(); | |
0 | 862 } |
863 | |
864 void os::setup_fpu() { | |
865 #ifndef AMD64 | |
866 address fpu_cntrl = StubRoutines::addr_fpu_cntrl_wrd_std(); | |
867 __asm__ volatile ( "fldcw (%0)" : | |
868 : "r" (fpu_cntrl) : "memory"); | |
869 #endif // !AMD64 | |
870 } | |
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871 |
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872 #ifndef PRODUCT |
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873 void os::verify_stack_alignment() { |
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874 #ifdef AMD64 |
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875 assert(((intptr_t)os::current_stack_pointer() & (StackAlignmentInBytes-1)) == 0, "incorrect stack alignment"); |
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876 #endif |
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877 } |
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878 #endif |
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879 |
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880 |
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881 /* |
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882 * IA32 only: execute code at a high address in case buggy NX emulation is present. I.e. avoid CS limit |
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883 * updates (JDK-8023956). |
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884 */ |
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885 void os::workaround_expand_exec_shield_cs_limit() { |
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886 #if defined(IA32) |
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887 size_t page_size = os::vm_page_size(); |
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888 /* |
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889 * Take the highest VA the OS will give us and exec |
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890 * |
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891 * Although using -(pagesz) as mmap hint works on newer kernel as you would |
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892 * think, older variants affected by this work-around don't (search forward only). |
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893 * |
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894 * On the affected distributions, we understand the memory layout to be: |
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895 * |
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896 * TASK_LIMIT= 3G, main stack base close to TASK_LIMT. |
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897 * |
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898 * A few pages south main stack will do it. |
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899 * |
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900 * If we are embedded in an app other than launcher (initial != main stack), |
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901 * we don't have much control or understanding of the address space, just let it slide. |
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902 */ |
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903 char* hint = (char*) (Linux::initial_thread_stack_bottom() - |
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904 ((StackYellowPages + StackRedPages + 1) * page_size)); |
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905 char* codebuf = os::reserve_memory(page_size, hint); |
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906 if ( (codebuf == NULL) || (!os::commit_memory(codebuf, page_size, true)) ) { |
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907 return; // No matter, we tried, best effort. |
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908 } |
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909 if (PrintMiscellaneous && (Verbose || WizardMode)) { |
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910 tty->print_cr("[CS limit NX emulation work-around, exec code at: %p]", codebuf); |
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911 } |
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912 |
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913 // Some code to exec: the 'ret' instruction |
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914 codebuf[0] = 0xC3; |
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915 |
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916 // Call the code in the codebuf |
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917 __asm__ volatile("call *%0" : : "r"(codebuf)); |
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918 |
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919 // keep the page mapped so CS limit isn't reduced. |
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920 #endif |
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921 } |