Mercurial > jdk8-mips64-public > hotspot / file revision

 /*

  * Copyright (c) 2003, 2007, Oracle and/or its affiliates. All rights reserved.

  * Copyright 2007, 2008, 2009, 2010 Red Hat, Inc.

  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

  *

  * This code is free software; you can redistribute it and/or modify it

  * under the terms of the GNU General Public License version 2 only, as

  * published by the Free Software Foundation.

  *

  * This code is distributed in the hope that it will be useful, but WITHOUT

  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

  * version 2 for more details (a copy is included in the LICENSE file that

  * accompanied this code).

  *

  * You should have received a copy of the GNU General Public License version

  * 2 along with this work; if not, write to the Free Software Foundation,

  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

  *

  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

  * or visit www.oracle.com if you need additional information or have any

  * questions.

  *

  */

 // do not include precompiled header file

 #include "incls/_os_linux_zero.cpp.incl"

 address os::current_stack_pointer() {

   address dummy = (address) &dummy;

   return dummy;

 }

 frame os::get_sender_for_C_frame(frame* fr) {

   ShouldNotCallThis();

 }

 frame os::current_frame() {

   // The only thing that calls this is the stack printing code in

   // VMError::report:

   //   - Step 110 (printing stack bounds) uses the sp in the frame

   //     to determine the amount of free space on the stack.  We

   //     set the sp to a close approximation of the real value in

   //     order to allow this step to complete.

   //   - Step 120 (printing native stack) tries to walk the stack.

   //     The frame we create has a NULL pc, which is ignored as an

   //     invalid frame.

   frame dummy = frame();

   dummy.set_sp((intptr_t *) current_stack_pointer());

   return dummy;

 }

 char* os::non_memory_address_word() {

   // Must never look like an address returned by reserve_memory,

   // even in its subfields (as defined by the CPU immediate fields,

   // if the CPU splits constants across multiple instructions).

 #ifdef SPARC

   // On SPARC, 0 != %hi(any real address), because there is no

   // allocation in the first 1Kb of the virtual address space.

   return (char *) 0;

 #else

   // This is the value for x86; works pretty well for PPC too.

   return (char *) -1;

 #endif // SPARC

 }

 void os::initialize_thread() {

   // Nothing to do.

 }

 address os::Linux::ucontext_get_pc(ucontext_t* uc) {

   ShouldNotCallThis();

 }

 ExtendedPC os::fetch_frame_from_context(void* ucVoid,

                                         intptr_t** ret_sp,

                                         intptr_t** ret_fp) {

   ShouldNotCallThis();

 }

 frame os::fetch_frame_from_context(void* ucVoid) {

   ShouldNotCallThis();

 }

 extern "C" int

 JVM_handle_linux_signal(int sig,

                         siginfo_t* info,

                         void* ucVoid,

                         int abort_if_unrecognized) {

   ucontext_t* uc = (ucontext_t*) ucVoid;

   Thread* t = ThreadLocalStorage::get_thread_slow();

   SignalHandlerMark shm(t);

   // Note: it's not uncommon that JNI code uses signal/sigset to

   // install then restore certain signal handler (e.g. to temporarily

   // block SIGPIPE, or have a SIGILL handler when detecting CPU

   // type). When that happens, JVM_handle_linux_signal() might be

   // invoked with junk info/ucVoid. To avoid unnecessary crash when

   // libjsig is not preloaded, try handle signals that do not require

   // siginfo/ucontext first.

   if (sig == SIGPIPE || sig == SIGXFSZ) {

     // allow chained handler to go first

     if (os::Linux::chained_handler(sig, info, ucVoid)) {

       return true;

     } else {

       if (PrintMiscellaneous && (WizardMode || Verbose)) {

         char buf[64];

         warning("Ignoring %s - see bugs 4229104 or 646499219",

                 os::exception_name(sig, buf, sizeof(buf)));

       }

       return true;

     }

   }

   JavaThread* thread = NULL;

   VMThread* vmthread = NULL;

   if (os::Linux::signal_handlers_are_installed) {

     if (t != NULL ){

       if(t->is_Java_thread()) {

         thread = (JavaThread*)t;

       }

       else if(t->is_VM_thread()){

         vmthread = (VMThread *)t;

       }

     }

   }

   if (info != NULL && thread != NULL) {

     // Handle ALL stack overflow variations here

     if (sig == SIGSEGV) {

       address addr = (address) info->si_addr;

       // check if fault address is within thread stack

       if (addr < thread->stack_base() &&

           addr >= thread->stack_base() - thread->stack_size()) {

         // stack overflow

         if (thread->in_stack_yellow_zone(addr)) {

           thread->disable_stack_yellow_zone();

           ShouldNotCallThis();

         }

         else if (thread->in_stack_red_zone(addr)) {

           thread->disable_stack_red_zone();

           ShouldNotCallThis();

         }

         else {

           // Accessing stack address below sp may cause SEGV if

           // current thread has MAP_GROWSDOWN stack. This should

           // only happen when current thread was created by user

           // code with MAP_GROWSDOWN flag and then attached to VM.

           // See notes in os_linux.cpp.

           if (thread->osthread()->expanding_stack() == 0) {

             thread->osthread()->set_expanding_stack();

             if (os::Linux::manually_expand_stack(thread, addr)) {

               thread->osthread()->clear_expanding_stack();

               return true;

             }

             thread->osthread()->clear_expanding_stack();

           }

           else {

             fatal("recursive segv. expanding stack.");

           }

         }

       }

     }

     /*if (thread->thread_state() == _thread_in_Java) {

       ShouldNotCallThis();

     }

     else*/ if (thread->thread_state() == _thread_in_vm &&

                sig == SIGBUS && thread->doing_unsafe_access()) {

       ShouldNotCallThis();

     }

     // jni_fast_Get<Primitive>Field can trap at certain pc's if a GC

     // kicks in and the heap gets shrunk before the field access.

     /*if (sig == SIGSEGV || sig == SIGBUS) {

       address addr = JNI_FastGetField::find_slowcase_pc(pc);

       if (addr != (address)-1) {

         stub = addr;

       }

     }*/

     // Check to see if we caught the safepoint code in the process

     // of write protecting the memory serialization page.  It write

     // enables the page immediately after protecting it so we can

     // just return to retry the write.

     if (sig == SIGSEGV &&

         os::is_memory_serialize_page(thread, (address) info->si_addr)) {

       // Block current thread until permission is restored.

       os::block_on_serialize_page_trap();

       return true;

     }

   }

   // signal-chaining

   if (os::Linux::chained_handler(sig, info, ucVoid)) {

      return true;

   }

   if (!abort_if_unrecognized) {

     // caller wants another chance, so give it to him

     return false;

   }

 #ifndef PRODUCT

   if (sig == SIGSEGV) {

     fatal("\n#"

           "\n#    /--------------------\\"

           "\n#    | segmentation fault |"

           "\n#    \\---\\ /--------------/"

           "\n#        /"

           "\n#    [-]        |\\_/|    "

           "\n#    (+)=C      |o o|__  "

           "\n#    | |        =-*-=__\\ "

           "\n#    OOO        c_c_(___)");

   }

 #endif // !PRODUCT

   const char *fmt = "caught unhandled signal %d";

   char buf[64];

   sprintf(buf, fmt, sig);

   fatal(buf);

 }

 void os::Linux::init_thread_fpu_state(void) {

   // Nothing to do

 }

 int os::Linux::get_fpu_control_word() {

   ShouldNotCallThis();

 }

 void os::Linux::set_fpu_control_word(int fpu) {

   ShouldNotCallThis();

 }

 bool os::is_allocatable(size_t bytes) {

 #ifdef _LP64

   return true;

 #else

   if (bytes < 2 * G) {

     return true;

   }

   char* addr = reserve_memory(bytes, NULL);

   if (addr != NULL) {

     release_memory(addr, bytes);

   }

   return addr != NULL;

 #endif // _LP64

 }

 ///////////////////////////////////////////////////////////////////////////////

 // thread stack

 size_t os::Linux::min_stack_allowed = 64 * K;

 bool os::Linux::supports_variable_stack_size() {

   return true;

 }

 size_t os::Linux::default_stack_size(os::ThreadType thr_type) {

 #ifdef _LP64

   size_t s = (thr_type == os::compiler_thread ? 4 * M : 1 * M);

 #else

   size_t s = (thr_type == os::compiler_thread ? 2 * M : 512 * K);

 #endif // _LP64

   return s;

 }

 size_t os::Linux::default_guard_size(os::ThreadType thr_type) {

   // Only enable glibc guard pages for non-Java threads

   // (Java threads have HotSpot guard pages)

   return (thr_type == java_thread ? 0 : page_size());

 }

 static void current_stack_region(address *bottom, size_t *size) {

   pthread_attr_t attr;

   int res = pthread_getattr_np(pthread_self(), &attr);

   if (res != 0) {

     if (res == ENOMEM) {

       vm_exit_out_of_memory(0, "pthread_getattr_np");

     }

     else {

       fatal(err_msg("pthread_getattr_np failed with errno = %d", res));

     }

   }

   address stack_bottom;

   size_t stack_bytes;

   res = pthread_attr_getstack(&attr, (void **) &stack_bottom, &stack_bytes);

   if (res != 0) {

     fatal(err_msg("pthread_attr_getstack failed with errno = %d", res));

   }

   address stack_top = stack_bottom + stack_bytes;

   // The block of memory returned by pthread_attr_getstack() includes

   // guard pages where present.  We need to trim these off.

   size_t page_bytes = os::Linux::page_size();

   assert(((intptr_t) stack_bottom & (page_bytes - 1)) == 0, "unaligned stack");

   size_t guard_bytes;

   res = pthread_attr_getguardsize(&attr, &guard_bytes);

   if (res != 0) {

     fatal(err_msg("pthread_attr_getguardsize failed with errno = %d", res));

   }

   int guard_pages = align_size_up(guard_bytes, page_bytes) / page_bytes;

   assert(guard_bytes == guard_pages * page_bytes, "unaligned guard");

 #ifdef IA64

   // IA64 has two stacks sharing the same area of memory, a normal

   // stack growing downwards and a register stack growing upwards.

   // Guard pages, if present, are in the centre.  This code splits

   // the stack in two even without guard pages, though in theory

   // there's nothing to stop us allocating more to the normal stack

   // or more to the register stack if one or the other were found

   // to grow faster.

   int total_pages = align_size_down(stack_bytes, page_bytes) / page_bytes;

   stack_bottom += (total_pages - guard_pages) / 2 * page_bytes;

 #endif // IA64

   stack_bottom += guard_bytes;

   pthread_attr_destroy(&attr);

   // The initial thread has a growable stack, and the size reported

   // by pthread_attr_getstack is the maximum size it could possibly

   // be given what currently mapped.  This can be huge, so we cap it.

   if (os::Linux::is_initial_thread()) {

     stack_bytes = stack_top - stack_bottom;

     if (stack_bytes > JavaThread::stack_size_at_create())

       stack_bytes = JavaThread::stack_size_at_create();

     stack_bottom = stack_top - stack_bytes;

   }

   assert(os::current_stack_pointer() >= stack_bottom, "should do");

   assert(os::current_stack_pointer() < stack_top, "should do");

   *bottom = stack_bottom;

   *size = stack_top - stack_bottom;

 }

 address os::current_stack_base() {

   address bottom;

   size_t size;

   current_stack_region(&bottom, &size);

   return bottom + size;

 }

 size_t os::current_stack_size() {

   // stack size includes normal stack and HotSpot guard pages

   address bottom;

   size_t size;

   current_stack_region(&bottom, &size);

   return size;

 }

 /////////////////////////////////////////////////////////////////////////////

 // helper functions for fatal error handler

 void os::print_context(outputStream* st, void* context) {

   ShouldNotCallThis();

 }

 /////////////////////////////////////////////////////////////////////////////

 // Stubs for things that would be in linux_zero.s if it existed.

 // You probably want to disassemble these monkeys to check they're ok.

 extern "C" {

   int SpinPause() {

   }

   int SafeFetch32(int *adr, int errValue) {

     int value = errValue;

     value = *adr;

     return value;

   }

   intptr_t SafeFetchN(intptr_t *adr, intptr_t errValue) {

     intptr_t value = errValue;

     value = *adr;

     return value;

   }

   void _Copy_conjoint_jshorts_atomic(jshort* from, jshort* to, size_t count) {

     if (from > to) {

       jshort *end = from + count;

       while (from < end)

         *(to++) = *(from++);

     }

     else if (from < to) {

       jshort *end = from;

       from += count - 1;

       to   += count - 1;

       while (from >= end)

         *(to--) = *(from--);

     }

   }

   void _Copy_conjoint_jints_atomic(jint* from, jint* to, size_t count) {

     if (from > to) {

       jint *end = from + count;

       while (from < end)

         *(to++) = *(from++);

     }

     else if (from < to) {

       jint *end = from;

       from += count - 1;

       to   += count - 1;

       while (from >= end)

         *(to--) = *(from--);

     }

   }

   void _Copy_conjoint_jlongs_atomic(jlong* from, jlong* to, size_t count) {

     if (from > to) {

       jlong *end = from + count;

       while (from < end)

         os::atomic_copy64(from++, to++);

     }

     else if (from < to) {

       jlong *end = from;

       from += count - 1;

       to   += count - 1;

       while (from >= end)

         os::atomic_copy64(from--, to--);

     }

   }

   void _Copy_arrayof_conjoint_bytes(HeapWord* from,

                                     HeapWord* to,

                                     size_t    count) {

     memmove(to, from, count);

   }

   void _Copy_arrayof_conjoint_jshorts(HeapWord* from,

                                       HeapWord* to,

                                       size_t    count) {

     memmove(to, from, count * 2);

   }

   void _Copy_arrayof_conjoint_jints(HeapWord* from,

                                     HeapWord* to,

                                     size_t    count) {

     memmove(to, from, count * 4);

   }

   void _Copy_arrayof_conjoint_jlongs(HeapWord* from,

                                      HeapWord* to,

                                      size_t    count) {

     memmove(to, from, count * 8);

   }

 };

 /////////////////////////////////////////////////////////////////////////////

 // Implementations of atomic operations not supported by processors.

 //  -- http://gcc.gnu.org/onlinedocs/gcc-4.2.1/gcc/Atomic-Builtins.html

 #ifndef _LP64

 extern "C" {

   long long unsigned int __sync_val_compare_and_swap_8(

     volatile void *ptr,

     long long unsigned int oldval,

     long long unsigned int newval) {

     ShouldNotCallThis();

   }

 };

 #endif // !_LP64