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