never@1445: /*
stefank@2314:  * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved.
twisti@1611:  * Copyright 2007, 2008, 2009, 2010 Red Hat, Inc.
never@1445:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
never@1445:  *
never@1445:  * This code is free software; you can redistribute it and/or modify it
never@1445:  * under the terms of the GNU General Public License version 2 only, as
never@1445:  * published by the Free Software Foundation.
never@1445:  *
never@1445:  * This code is distributed in the hope that it will be useful, but WITHOUT
never@1445:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
never@1445:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
never@1445:  * version 2 for more details (a copy is included in the LICENSE file that
never@1445:  * accompanied this code).
never@1445:  *
never@1445:  * You should have received a copy of the GNU General Public License version
never@1445:  * 2 along with this work; if not, write to the Free Software Foundation,
never@1445:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
never@1445:  *
trims@1907:  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
trims@1907:  * or visit www.oracle.com if you need additional information or have any
trims@1907:  * questions.
never@1445:  *
never@1445:  */
never@1445: 
stefank@2314: // no precompiled headers
stefank@2314: #include "assembler_zero.inline.hpp"
stefank@2314: #include "classfile/classLoader.hpp"
stefank@2314: #include "classfile/systemDictionary.hpp"
stefank@2314: #include "classfile/vmSymbols.hpp"
stefank@2314: #include "code/icBuffer.hpp"
stefank@2314: #include "code/vtableStubs.hpp"
stefank@2314: #include "interpreter/interpreter.hpp"
stefank@2314: #include "jvm_linux.h"
stefank@2314: #include "memory/allocation.inline.hpp"
stefank@2314: #include "mutex_linux.inline.hpp"
stefank@2314: #include "nativeInst_zero.hpp"
stefank@2314: #include "os_share_linux.hpp"
stefank@2314: #include "prims/jniFastGetField.hpp"
stefank@2314: #include "prims/jvm.h"
stefank@2314: #include "prims/jvm_misc.hpp"
stefank@2314: #include "runtime/arguments.hpp"
stefank@2314: #include "runtime/extendedPC.hpp"
stefank@2314: #include "runtime/frame.inline.hpp"
stefank@2314: #include "runtime/interfaceSupport.hpp"
stefank@2314: #include "runtime/java.hpp"
stefank@2314: #include "runtime/javaCalls.hpp"
stefank@2314: #include "runtime/mutexLocker.hpp"
stefank@2314: #include "runtime/osThread.hpp"
stefank@2314: #include "runtime/sharedRuntime.hpp"
stefank@2314: #include "runtime/stubRoutines.hpp"
stefank@2314: #include "runtime/timer.hpp"
stefank@2314: #include "thread_linux.inline.hpp"
stefank@2314: #include "utilities/events.hpp"
stefank@2314: #include "utilities/vmError.hpp"
stefank@2314: #ifdef COMPILER1
stefank@2314: #include "c1/c1_Runtime1.hpp"
stefank@2314: #endif
stefank@2314: #ifdef COMPILER2
stefank@2314: #include "opto/runtime.hpp"
stefank@2314: #endif
never@1445: 
never@1445: address os::current_stack_pointer() {
never@1445:   address dummy = (address) &dummy;
never@1445:   return dummy;
never@1445: }
never@1445: 
never@1445: frame os::get_sender_for_C_frame(frame* fr) {
never@1445:   ShouldNotCallThis();
never@1445: }
never@1445: 
never@1445: frame os::current_frame() {
never@1445:   // The only thing that calls this is the stack printing code in
never@1445:   // VMError::report:
never@1445:   //   - Step 110 (printing stack bounds) uses the sp in the frame
never@1445:   //     to determine the amount of free space on the stack.  We
never@1445:   //     set the sp to a close approximation of the real value in
never@1445:   //     order to allow this step to complete.
never@1445:   //   - Step 120 (printing native stack) tries to walk the stack.
never@1445:   //     The frame we create has a NULL pc, which is ignored as an
never@1445:   //     invalid frame.
never@1445:   frame dummy = frame();
never@1445:   dummy.set_sp((intptr_t *) current_stack_pointer());
never@1445:   return dummy;
never@1445: }
never@1445: 
never@1445: char* os::non_memory_address_word() {
never@1445:   // Must never look like an address returned by reserve_memory,
never@1445:   // even in its subfields (as defined by the CPU immediate fields,
never@1445:   // if the CPU splits constants across multiple instructions).
never@1445: #ifdef SPARC
never@1445:   // On SPARC, 0 != %hi(any real address), because there is no
never@1445:   // allocation in the first 1Kb of the virtual address space.
never@1445:   return (char *) 0;
never@1445: #else
never@1445:   // This is the value for x86; works pretty well for PPC too.
never@1445:   return (char *) -1;
never@1445: #endif // SPARC
never@1445: }
never@1445: 
never@1445: void os::initialize_thread() {
never@1445:   // Nothing to do.
never@1445: }
never@1445: 
never@1445: address os::Linux::ucontext_get_pc(ucontext_t* uc) {
never@1445:   ShouldNotCallThis();
never@1445: }
never@1445: 
never@1445: ExtendedPC os::fetch_frame_from_context(void* ucVoid,
never@1445:                                         intptr_t** ret_sp,
never@1445:                                         intptr_t** ret_fp) {
never@1445:   ShouldNotCallThis();
never@1445: }
never@1445: 
never@1445: frame os::fetch_frame_from_context(void* ucVoid) {
never@1445:   ShouldNotCallThis();
never@1445: }
never@1445: 
never@1445: extern "C" int
never@1445: JVM_handle_linux_signal(int sig,
never@1445:                         siginfo_t* info,
never@1445:                         void* ucVoid,
never@1445:                         int abort_if_unrecognized) {
never@1445:   ucontext_t* uc = (ucontext_t*) ucVoid;
never@1445: 
never@1445:   Thread* t = ThreadLocalStorage::get_thread_slow();
never@1445: 
never@1445:   SignalHandlerMark shm(t);
never@1445: 
never@1445:   // Note: it's not uncommon that JNI code uses signal/sigset to
never@1445:   // install then restore certain signal handler (e.g. to temporarily
never@1445:   // block SIGPIPE, or have a SIGILL handler when detecting CPU
never@1445:   // type). When that happens, JVM_handle_linux_signal() might be
never@1445:   // invoked with junk info/ucVoid. To avoid unnecessary crash when
never@1445:   // libjsig is not preloaded, try handle signals that do not require
never@1445:   // siginfo/ucontext first.
never@1445: 
never@1445:   if (sig == SIGPIPE || sig == SIGXFSZ) {
never@1445:     // allow chained handler to go first
never@1445:     if (os::Linux::chained_handler(sig, info, ucVoid)) {
never@1445:       return true;
never@1445:     } else {
never@1445:       if (PrintMiscellaneous && (WizardMode || Verbose)) {
never@1445:         char buf[64];
never@1445:         warning("Ignoring %s - see bugs 4229104 or 646499219",
never@1445:                 os::exception_name(sig, buf, sizeof(buf)));
never@1445:       }
never@1445:       return true;
never@1445:     }
never@1445:   }
never@1445: 
never@1445:   JavaThread* thread = NULL;
never@1445:   VMThread* vmthread = NULL;
never@1445:   if (os::Linux::signal_handlers_are_installed) {
never@1445:     if (t != NULL ){
never@1445:       if(t->is_Java_thread()) {
never@1445:         thread = (JavaThread*)t;
never@1445:       }
never@1445:       else if(t->is_VM_thread()){
never@1445:         vmthread = (VMThread *)t;
never@1445:       }
never@1445:     }
never@1445:   }
never@1445: 
never@1445:   if (info != NULL && thread != NULL) {
never@1445:     // Handle ALL stack overflow variations here
never@1445:     if (sig == SIGSEGV) {
never@1445:       address addr = (address) info->si_addr;
never@1445: 
never@1445:       // check if fault address is within thread stack
never@1445:       if (addr < thread->stack_base() &&
never@1445:           addr >= thread->stack_base() - thread->stack_size()) {
never@1445:         // stack overflow
never@1445:         if (thread->in_stack_yellow_zone(addr)) {
never@1445:           thread->disable_stack_yellow_zone();
never@1445:           ShouldNotCallThis();
never@1445:         }
never@1445:         else if (thread->in_stack_red_zone(addr)) {
never@1445:           thread->disable_stack_red_zone();
never@1445:           ShouldNotCallThis();
never@1445:         }
never@1445:         else {
never@1445:           // Accessing stack address below sp may cause SEGV if
never@1445:           // current thread has MAP_GROWSDOWN stack. This should
never@1445:           // only happen when current thread was created by user
never@1445:           // code with MAP_GROWSDOWN flag and then attached to VM.
never@1445:           // See notes in os_linux.cpp.
never@1445:           if (thread->osthread()->expanding_stack() == 0) {
never@1445:             thread->osthread()->set_expanding_stack();
never@1445:             if (os::Linux::manually_expand_stack(thread, addr)) {
never@1445:               thread->osthread()->clear_expanding_stack();
never@1445:               return true;
never@1445:             }
never@1445:             thread->osthread()->clear_expanding_stack();
never@1445:           }
never@1445:           else {
never@1445:             fatal("recursive segv. expanding stack.");
never@1445:           }
never@1445:         }
never@1445:       }
never@1445:     }
never@1445: 
never@1445:     /*if (thread->thread_state() == _thread_in_Java) {
never@1445:       ShouldNotCallThis();
never@1445:     }
never@1445:     else*/ if (thread->thread_state() == _thread_in_vm &&
never@1445:                sig == SIGBUS && thread->doing_unsafe_access()) {
never@1445:       ShouldNotCallThis();
never@1445:     }
never@1445: 
never@1445:     // jni_fast_Get<Primitive>Field can trap at certain pc's if a GC
never@1445:     // kicks in and the heap gets shrunk before the field access.
never@1445:     /*if (sig == SIGSEGV || sig == SIGBUS) {
never@1445:       address addr = JNI_FastGetField::find_slowcase_pc(pc);
never@1445:       if (addr != (address)-1) {
never@1445:         stub = addr;
never@1445:       }
never@1445:     }*/
never@1445: 
never@1445:     // Check to see if we caught the safepoint code in the process
never@1445:     // of write protecting the memory serialization page.  It write
never@1445:     // enables the page immediately after protecting it so we can
never@1445:     // just return to retry the write.
never@1445:     if (sig == SIGSEGV &&
never@1445:         os::is_memory_serialize_page(thread, (address) info->si_addr)) {
never@1445:       // Block current thread until permission is restored.
never@1445:       os::block_on_serialize_page_trap();
never@1445:       return true;
never@1445:     }
never@1445:   }
never@1445: 
never@1445:   // signal-chaining
never@1445:   if (os::Linux::chained_handler(sig, info, ucVoid)) {
never@1445:      return true;
never@1445:   }
never@1445: 
never@1445:   if (!abort_if_unrecognized) {
never@1445:     // caller wants another chance, so give it to him
never@1445:     return false;
never@1445:   }
never@1445: 
never@1445: #ifndef PRODUCT
never@1445:   if (sig == SIGSEGV) {
never@1445:     fatal("\n#"
never@1445:           "\n#    /--------------------\\"
never@1445:           "\n#    | segmentation fault |"
never@1445:           "\n#    \\---\\ /--------------/"
never@1445:           "\n#        /"
never@1445:           "\n#    [-]        |\\_/|    "
never@1445:           "\n#    (+)=C      |o o|__  "
never@1445:           "\n#    | |        =-*-=__\\ "
never@1445:           "\n#    OOO        c_c_(___)");
never@1445:   }
never@1445: #endif // !PRODUCT
never@1445: 
never@1445:   const char *fmt = "caught unhandled signal %d";
never@1445:   char buf[64];
never@1445: 
never@1445:   sprintf(buf, fmt, sig);
never@1445:   fatal(buf);
never@1445: }
never@1445: 
never@1445: void os::Linux::init_thread_fpu_state(void) {
never@1445:   // Nothing to do
never@1445: }
never@1445: 
never@1445: int os::Linux::get_fpu_control_word() {
never@1445:   ShouldNotCallThis();
never@1445: }
never@1445: 
never@1445: void os::Linux::set_fpu_control_word(int fpu) {
never@1445:   ShouldNotCallThis();
never@1445: }
never@1445: 
never@1445: bool os::is_allocatable(size_t bytes) {
twisti@1611: #ifdef _LP64
twisti@1611:   return true;
twisti@1611: #else
twisti@1611:   if (bytes < 2 * G) {
twisti@1611:     return true;
twisti@1611:   }
twisti@1611: 
twisti@1611:   char* addr = reserve_memory(bytes, NULL);
twisti@1611: 
twisti@1611:   if (addr != NULL) {
twisti@1611:     release_memory(addr, bytes);
twisti@1611:   }
twisti@1611: 
twisti@1611:   return addr != NULL;
twisti@1611: #endif // _LP64
never@1445: }
never@1445: 
never@1445: ///////////////////////////////////////////////////////////////////////////////
never@1445: // thread stack
never@1445: 
never@1445: size_t os::Linux::min_stack_allowed = 64 * K;
never@1445: 
never@1445: bool os::Linux::supports_variable_stack_size() {
never@1445:   return true;
never@1445: }
never@1445: 
never@1445: size_t os::Linux::default_stack_size(os::ThreadType thr_type) {
never@1445: #ifdef _LP64
never@1445:   size_t s = (thr_type == os::compiler_thread ? 4 * M : 1 * M);
never@1445: #else
never@1445:   size_t s = (thr_type == os::compiler_thread ? 2 * M : 512 * K);
never@1445: #endif // _LP64
never@1445:   return s;
never@1445: }
never@1445: 
never@1445: size_t os::Linux::default_guard_size(os::ThreadType thr_type) {
never@1445:   // Only enable glibc guard pages for non-Java threads
never@1445:   // (Java threads have HotSpot guard pages)
never@1445:   return (thr_type == java_thread ? 0 : page_size());
never@1445: }
never@1445: 
never@1445: static void current_stack_region(address *bottom, size_t *size) {
never@1445:   pthread_attr_t attr;
never@1445:   int res = pthread_getattr_np(pthread_self(), &attr);
never@1445:   if (res != 0) {
never@1445:     if (res == ENOMEM) {
never@1445:       vm_exit_out_of_memory(0, "pthread_getattr_np");
never@1445:     }
never@1445:     else {
jcoomes@1877:       fatal(err_msg("pthread_getattr_np failed with errno = %d", res));
never@1445:     }
never@1445:   }
never@1445: 
never@1445:   address stack_bottom;
never@1445:   size_t stack_bytes;
never@1445:   res = pthread_attr_getstack(&attr, (void **) &stack_bottom, &stack_bytes);
never@1445:   if (res != 0) {
jcoomes@1877:     fatal(err_msg("pthread_attr_getstack failed with errno = %d", res));
never@1445:   }
never@1445:   address stack_top = stack_bottom + stack_bytes;
never@1445: 
never@1445:   // The block of memory returned by pthread_attr_getstack() includes
never@1445:   // guard pages where present.  We need to trim these off.
never@1445:   size_t page_bytes = os::Linux::page_size();
never@1445:   assert(((intptr_t) stack_bottom & (page_bytes - 1)) == 0, "unaligned stack");
never@1445: 
never@1445:   size_t guard_bytes;
never@1445:   res = pthread_attr_getguardsize(&attr, &guard_bytes);
never@1445:   if (res != 0) {
jcoomes@1877:     fatal(err_msg("pthread_attr_getguardsize failed with errno = %d", res));
never@1445:   }
never@1445:   int guard_pages = align_size_up(guard_bytes, page_bytes) / page_bytes;
never@1445:   assert(guard_bytes == guard_pages * page_bytes, "unaligned guard");
never@1445: 
never@1445: #ifdef IA64
never@1445:   // IA64 has two stacks sharing the same area of memory, a normal
never@1445:   // stack growing downwards and a register stack growing upwards.
never@1445:   // Guard pages, if present, are in the centre.  This code splits
never@1445:   // the stack in two even without guard pages, though in theory
never@1445:   // there's nothing to stop us allocating more to the normal stack
never@1445:   // or more to the register stack if one or the other were found
never@1445:   // to grow faster.
never@1445:   int total_pages = align_size_down(stack_bytes, page_bytes) / page_bytes;
never@1445:   stack_bottom += (total_pages - guard_pages) / 2 * page_bytes;
never@1445: #endif // IA64
never@1445: 
never@1445:   stack_bottom += guard_bytes;
never@1445: 
never@1445:   pthread_attr_destroy(&attr);
never@1445: 
never@1445:   // The initial thread has a growable stack, and the size reported
never@1445:   // by pthread_attr_getstack is the maximum size it could possibly
never@1445:   // be given what currently mapped.  This can be huge, so we cap it.
never@1445:   if (os::Linux::is_initial_thread()) {
never@1445:     stack_bytes = stack_top - stack_bottom;
never@1445: 
never@1445:     if (stack_bytes > JavaThread::stack_size_at_create())
never@1445:       stack_bytes = JavaThread::stack_size_at_create();
never@1445: 
never@1445:     stack_bottom = stack_top - stack_bytes;
never@1445:   }
never@1445: 
never@1445:   assert(os::current_stack_pointer() >= stack_bottom, "should do");
never@1445:   assert(os::current_stack_pointer() < stack_top, "should do");
never@1445: 
never@1445:   *bottom = stack_bottom;
never@1445:   *size = stack_top - stack_bottom;
never@1445: }
never@1445: 
never@1445: address os::current_stack_base() {
never@1445:   address bottom;
never@1445:   size_t size;
never@1445:   current_stack_region(&bottom, &size);
never@1445:   return bottom + size;
never@1445: }
never@1445: 
never@1445: size_t os::current_stack_size() {
never@1445:   // stack size includes normal stack and HotSpot guard pages
never@1445:   address bottom;
never@1445:   size_t size;
never@1445:   current_stack_region(&bottom, &size);
never@1445:   return size;
never@1445: }
never@1445: 
never@1445: /////////////////////////////////////////////////////////////////////////////
never@1445: // helper functions for fatal error handler
never@1445: 
never@1445: void os::print_context(outputStream* st, void* context) {
never@1445:   ShouldNotCallThis();
never@1445: }
never@1445: 
twisti@2312: void os::print_register_info(outputStream *st, void *context) {
twisti@2312:   ShouldNotCallThis();
twisti@2312: }
twisti@2312: 
never@1445: /////////////////////////////////////////////////////////////////////////////
never@1445: // Stubs for things that would be in linux_zero.s if it existed.
never@1445: // You probably want to disassemble these monkeys to check they're ok.
never@1445: 
never@1445: extern "C" {
never@1445:   int SpinPause() {
never@1445:   }
never@1445: 
never@1445:   int SafeFetch32(int *adr, int errValue) {
never@1445:     int value = errValue;
never@1445:     value = *adr;
never@1445:     return value;
never@1445:   }
never@1445:   intptr_t SafeFetchN(intptr_t *adr, intptr_t errValue) {
never@1445:     intptr_t value = errValue;
never@1445:     value = *adr;
never@1445:     return value;
never@1445:   }
never@1445: 
never@1445:   void _Copy_conjoint_jshorts_atomic(jshort* from, jshort* to, size_t count) {
never@1445:     if (from > to) {
never@1445:       jshort *end = from + count;
never@1445:       while (from < end)
never@1445:         *(to++) = *(from++);
never@1445:     }
never@1445:     else if (from < to) {
never@1445:       jshort *end = from;
never@1445:       from += count - 1;
never@1445:       to   += count - 1;
never@1445:       while (from >= end)
never@1445:         *(to--) = *(from--);
never@1445:     }
never@1445:   }
never@1445:   void _Copy_conjoint_jints_atomic(jint* from, jint* to, size_t count) {
never@1445:     if (from > to) {
never@1445:       jint *end = from + count;
never@1445:       while (from < end)
never@1445:         *(to++) = *(from++);
never@1445:     }
never@1445:     else if (from < to) {
never@1445:       jint *end = from;
never@1445:       from += count - 1;
never@1445:       to   += count - 1;
never@1445:       while (from >= end)
never@1445:         *(to--) = *(from--);
never@1445:     }
never@1445:   }
never@1445:   void _Copy_conjoint_jlongs_atomic(jlong* from, jlong* to, size_t count) {
never@1445:     if (from > to) {
never@1445:       jlong *end = from + count;
never@1445:       while (from < end)
never@1445:         os::atomic_copy64(from++, to++);
never@1445:     }
never@1445:     else if (from < to) {
never@1445:       jlong *end = from;
never@1445:       from += count - 1;
never@1445:       to   += count - 1;
never@1445:       while (from >= end)
never@1445:         os::atomic_copy64(from--, to--);
never@1445:     }
never@1445:   }
never@1445: 
never@1445:   void _Copy_arrayof_conjoint_bytes(HeapWord* from,
never@1445:                                     HeapWord* to,
never@1445:                                     size_t    count) {
twisti@2084:     memmove(to, from, count);
never@1445:   }
never@1445:   void _Copy_arrayof_conjoint_jshorts(HeapWord* from,
never@1445:                                       HeapWord* to,
never@1445:                                       size_t    count) {
twisti@2084:     memmove(to, from, count * 2);
never@1445:   }
never@1445:   void _Copy_arrayof_conjoint_jints(HeapWord* from,
never@1445:                                     HeapWord* to,
never@1445:                                     size_t    count) {
twisti@2084:     memmove(to, from, count * 4);
never@1445:   }
never@1445:   void _Copy_arrayof_conjoint_jlongs(HeapWord* from,
never@1445:                                      HeapWord* to,
never@1445:                                      size_t    count) {
twisti@2084:     memmove(to, from, count * 8);
never@1445:   }
never@1445: };
never@1445: 
never@1445: /////////////////////////////////////////////////////////////////////////////
never@1445: // Implementations of atomic operations not supported by processors.
never@1445: //  -- http://gcc.gnu.org/onlinedocs/gcc-4.2.1/gcc/Atomic-Builtins.html
never@1445: 
never@1445: #ifndef _LP64
never@1445: extern "C" {
never@1445:   long long unsigned int __sync_val_compare_and_swap_8(
never@1445:     volatile void *ptr,
never@1445:     long long unsigned int oldval,
never@1445:     long long unsigned int newval) {
never@1445:     ShouldNotCallThis();
never@1445:   }
never@1445: };
never@1445: #endif // !_LP64