jdk8-mips64-public/hotspot: src/os_cpu/linux_mips/vm/os_linux

src/os_cpu/linux_mips/vm/os_linux_mips.cpp@1ccc5a3b3671 (annotated)

src/os_cpu/linux_mips/vm/os_linux_mips.cpp

Thu, 11 Oct 2018 09:53:13 +0800

author: huangxuguang
date: Thu, 11 Oct 2018 09:53:13 +0800
changeset 9251: 1ccc5a3b3671
parent 9228: 617b86d17edb
child 9256: e2410d272556
permissions: -rw-r--r--

 /*
  * Copyright (c) 1999, 2014, Oracle and/or its affiliates. All rights reserved.
  * Copyright (c) 2015, 2018, Loongson Technology. All rights reserved.
  * 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.
  *
  */
 // no precompiled headers
 #include "asm/macroAssembler.hpp"
 #include "classfile/classLoader.hpp"
 #include "classfile/systemDictionary.hpp"
 #include "classfile/vmSymbols.hpp"
 #include "code/icBuffer.hpp"
 #include "code/vtableStubs.hpp"
 #include "interpreter/interpreter.hpp"
 #include "jvm_linux.h"
 #include "memory/allocation.inline.hpp"
 #include "mutex_linux.inline.hpp"
 #include "os_share_linux.hpp"
 #include "prims/jniFastGetField.hpp"
 #include "prims/jvm.h"
 #include "prims/jvm_misc.hpp"
 #include "runtime/arguments.hpp"
 #include "runtime/extendedPC.hpp"
 #include "runtime/frame.inline.hpp"
 #include "runtime/interfaceSupport.hpp"
 #include "runtime/java.hpp"
 #include "runtime/javaCalls.hpp"
 #include "runtime/mutexLocker.hpp"
 #include "runtime/osThread.hpp"
 #include "runtime/sharedRuntime.hpp"
 #include "runtime/stubRoutines.hpp"
 #include "runtime/thread.inline.hpp"
 #include "runtime/timer.hpp"
 #include "utilities/events.hpp"
 #include "utilities/vmError.hpp"
 #include "utilities/debug.hpp"
 #include "compiler/disassembler.hpp"
 // put OS-includes here
 # include <sys/types.h>
 # include <sys/mman.h>
 # include <pthread.h>
 # include <signal.h>
 # include <errno.h>
 # include <dlfcn.h>
 # include <stdlib.h>
 # include <stdio.h>
 # include <unistd.h>
 # include <sys/resource.h>
 # include <pthread.h>
 # include <sys/stat.h>
 # include <sys/time.h>
 # include <sys/utsname.h>
 # include <sys/socket.h>
 # include <sys/wait.h>
 # include <pwd.h>
 # include <poll.h>
 # include <ucontext.h>
 # include <fpu_control.h>
 #define REG_SP 29
 #define REG_FP 30
 address os::current_stack_pointer() {
   register void *sp __asm__ ("$29");
   return (address) sp;
 }
 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).
   return (char*) -1;
 }
 void os::initialize_thread(Thread* thr) {
 // Nothing to do.
 }
 address os::Linux::ucontext_get_pc(ucontext_t * uc) {
   //return (address)uc->uc_mcontext.gregs[REG_PC];
   return (address)uc->uc_mcontext.pc;
 }
 intptr_t* os::Linux::ucontext_get_sp(ucontext_t * uc) {
   return (intptr_t*)uc->uc_mcontext.gregs[REG_SP];
 }
 intptr_t* os::Linux::ucontext_get_fp(ucontext_t * uc) {
   return (intptr_t*)uc->uc_mcontext.gregs[REG_FP];
 }
 // For Forte Analyzer AsyncGetCallTrace profiling support - thread
 // is currently interrupted by SIGPROF.
 // os::Solaris::fetch_frame_from_ucontext() tries to skip nested signal
 // frames. Currently we don't do that on Linux, so it's the same as
 // os::fetch_frame_from_context().
 ExtendedPC os::Linux::fetch_frame_from_ucontext(Thread* thread,
   ucontext_t* uc, intptr_t** ret_sp, intptr_t** ret_fp) {
   assert(thread != NULL, "just checking");
   assert(ret_sp != NULL, "just checking");
   assert(ret_fp != NULL, "just checking");
   return os::fetch_frame_from_context(uc, ret_sp, ret_fp);
 }
 ExtendedPC os::fetch_frame_from_context(void* ucVoid,
                     intptr_t** ret_sp, intptr_t** ret_fp) {
   ExtendedPC  epc;
   ucontext_t* uc = (ucontext_t*)ucVoid;
   if (uc != NULL) {
     epc = ExtendedPC(os::Linux::ucontext_get_pc(uc));
     if (ret_sp) *ret_sp = os::Linux::ucontext_get_sp(uc);
     if (ret_fp) *ret_fp = os::Linux::ucontext_get_fp(uc);
   } else {
     // construct empty ExtendedPC for return value checking
     epc = ExtendedPC(NULL);
     if (ret_sp) *ret_sp = (intptr_t *)NULL;
     if (ret_fp) *ret_fp = (intptr_t *)NULL;
   }
   return epc;
 }
 frame os::fetch_frame_from_context(void* ucVoid) {
   intptr_t* sp;
   intptr_t* fp;
   ExtendedPC epc = fetch_frame_from_context(ucVoid, &sp, &fp);
   return frame(sp, fp, epc.pc());
 }
 // By default, gcc always save frame pointer (%ebp/%rbp) on stack. It may get
 // turned off by -fomit-frame-pointer,
 frame os::get_sender_for_C_frame(frame* fr) {
   return frame(fr->sender_sp(), fr->link(), fr->sender_pc());
 }
 //intptr_t* _get_previous_fp() {
 jint* os::get_previous_fp() {
   int *pc;
   int sp;
   int *pc_limit = (int*)(void*)&os::get_previous_fp;
   int insn;
   {
     l_pc:;
     pc = (int*)&&l_pc;
     __asm__ __volatile__ ("move %0,  $sp" : "=r" (sp));
   }
   do {
     --pc;
     insn = *pc;
     switch(bitfield(insn, 16, 16)) {
       case 0x27bd:  /* addiu $sp,$sp,-i */
       case 0x23bd:  /* addi $sp,$sp,-i */
       case 0x67bd:  /* daddiu $sp,$sp,-i */
       case 0x63bd:  /* daddi $sp,$sp,-i */
         assert ((short)bitfield(insn, 0, 16)<0, "bad frame");
         sp -= (short)bitfield(insn, 0, 16);
         return (jint*)sp;
     }
   } while (pc>pc_limit);
   ShouldNotReachHere();
 }
 frame os::current_frame() {
   intptr_t* fp = (intptr_t*)get_previous_fp();
   frame myframe((intptr_t*)os::current_stack_pointer(),
                 (intptr_t*)fp,
                 CAST_FROM_FN_PTR(address, os::current_frame));
   if (os::is_first_C_frame(&myframe)) {
     // stack is not walkable
     return frame();
   } else {
     return os::get_sender_for_C_frame(&myframe);
   }
 }
 //x86 add 2 new assemble function here!
 extern "C" int
 JVM_handle_linux_signal(int sig,
                         siginfo_t* info,
                         void* ucVoid,
                         int abort_if_unrecognized) {
 #ifdef PRINT_SIGNAL_HANDLE
   tty->print_cr("Signal: signo=%d, sicode=%d, sierrno=%d, siaddr=%lx",
       info->si_signo,
       info->si_code,
       info->si_errno,
       info->si_addr);
 #endif
   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)) {
         warning("Ignoring SIGPIPE - see bug 4229104");
       }
       return true;
     }
   }
   JavaThread* thread = NULL;
   VMThread* vmthread = NULL;
   if (os::Linux::signal_handlers_are_installed) {
     if (t != NULL ){
       if(t->is_Java_thread()) {
 #ifdef PRINT_SIGNAL_HANDLE
         tty->print_cr("this thread is a java thread");
 #endif
         thread = (JavaThread*)t;
       }
       else if(t->is_VM_thread()){
 #ifdef PRINT_SIGNAL_HANDLE
         tty->print_cr("this thread is a VM thread\n");
 #endif
         vmthread = (VMThread *)t;
       }
     }
   }
   // decide if this trap can be handled by a stub
   address stub = NULL;
   address pc   = NULL;
   pc = (address) os::Linux::ucontext_get_pc(uc);
 #ifdef PRINT_SIGNAL_HANDLE
   tty->print_cr("pc=%lx", pc);
   os::print_context(tty, uc);
 #endif
   //%note os_trap_1
   if (info != NULL && uc != NULL && thread != NULL) {
     pc = (address) os::Linux::ucontext_get_pc(uc);
     // Handle ALL stack overflow variations here
     if (sig == SIGSEGV) {
       address addr = (address) info->si_addr;
 #ifdef PRINT_SIGNAL_HANDLE
       tty->print("handle all stack overflow variations: ");
       /*tty->print("addr = %lx, stack base = %lx, stack top = %lx\n",
         addr,
         thread->stack_base(),
         thread->stack_base() - thread->stack_size());
         */
 #endif
       // check if fault address is within thread stack
       if (addr < thread->stack_base() &&
           addr >= thread->stack_base() - thread->stack_size()) {
         // stack overflow
 #ifdef PRINT_SIGNAL_HANDLE
         tty->print("stack exception check \n");
 #endif
         if (thread->in_stack_yellow_zone(addr)) {
 #ifdef PRINT_SIGNAL_HANDLE
           tty->print("exception addr is in yellow zone\n");
 #endif
           thread->disable_stack_yellow_zone();
           if (thread->thread_state() == _thread_in_Java) {
             // Throw a stack overflow exception.  Guard pages will be reenabled
             // while unwinding the stack.
 #ifdef PRINT_SIGNAL_HANDLE
             tty->print("this thread is in java\n");
 #endif
             stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::STACK_OVERFLOW);
           } else {
             // Thread was in the vm or native code.  Return and try to finish.
 #ifdef PRINT_SIGNAL_HANDLE
             tty->print("this thread is in vm or native codes and return\n");
 #endif
             return 1;
           }
         } else if (thread->in_stack_red_zone(addr)) {
           // Fatal red zone violation.  Disable the guard pages and fall through
           // to handle_unexpected_exception way down below.
 #ifdef PRINT_SIGNAL_HANDLE
           tty->print("exception addr is in red zone\n");
 #endif
           thread->disable_stack_red_zone();
           tty->print_raw_cr("An irrecoverable stack overflow has occurred.");
           // This is a likely cause, but hard to verify. Let's just print
           // it as a hint.
           tty->print_raw_cr("Please check if any of your loaded .so files has "
                             "enabled executable stack (see man page execstack(8))");
         } 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.
 #ifdef PRINT_SIGNAL_HANDLE
           tty->print("exception addr is neither in yellow zone nor in the red one\n");
 #endif
           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 1;
              }
              thread->osthread()->clear_expanding_stack();
           } else {
              fatal("recursive segv. expanding stack.");
           }
         }
       } //addr <
     } //sig == SIGSEGV
     if (thread->thread_state() == _thread_in_Java) {
       // Java thread running in Java code => find exception handler if any
       // a fault inside compiled code, the interpreter, or a stub
 #ifdef PRINT_SIGNAL_HANDLE
       tty->print("java thread running in java code\n");
 #endif
       // Handle signal from NativeJump::patch_verified_entry().
       if (sig == SIGILL & nativeInstruction_at(pc)->is_sigill_zombie_not_entrant()) {
 #ifdef PRINT_SIGNAL_HANDLE
         tty->print_cr("verified entry = %lx, sig=%d", nativeInstruction_at(pc), sig);
 #endif
         stub = SharedRuntime::get_handle_wrong_method_stub();
       } else if (sig == SIGSEGV && os::is_poll_address((address)info->si_addr)) {
 #ifdef PRINT_SIGNAL_HANDLE
         tty->print_cr("polling address = %lx, sig=%d", os::get_polling_page(), sig);
 #endif
         stub = SharedRuntime::get_poll_stub(pc);
       } else if (sig == SIGBUS /* && info->si_code == BUS_OBJERR */) {
         // BugId 4454115: A read from a MappedByteBuffer can fault
         // here if the underlying file has been truncated.
         // Do not crash the VM in such a case.
         CodeBlob* cb = CodeCache::find_blob_unsafe(pc);
         nmethod* nm = cb->is_nmethod() ? (nmethod*)cb : NULL;
 #ifdef PRINT_SIGNAL_HANDLE
         tty->print("cb = %lx, nm = %lx\n", cb, nm);
 #endif
         if (nm != NULL && nm->has_unsafe_access()) {
           stub = StubRoutines::handler_for_unsafe_access();
         }
       } else if (sig == SIGFPE /* && info->si_code == FPE_INTDIV */) {
         // HACK: si_code does not work on linux 2.2.12-20!!!
         int op = pc[0] & 0x3f;
         int op1 = pc[3] & 0x3f;
         //FIXME, Must port to mips code!!
         switch (op) {
           case 0x1e:  //ddiv
           case 0x1f:  //ddivu
           case 0x1a:  //div
           case 0x1b:  //divu
           case 0x34:  //trap
             /* In MIPS, div_by_zero exception can only be triggered by explicit 'trap'.
              * Ref: [c1_LIRAssembler_mips.cpp] arithmetic_idiv()
              */
             stub = SharedRuntime::continuation_for_implicit_exception(thread,
                                     pc,
                                     SharedRuntime::IMPLICIT_DIVIDE_BY_ZERO);
             break;
           default:
             // TODO: handle more cases if we are using other x86 instructions
             //   that can generate SIGFPE signal on linux.
             tty->print_cr("unknown opcode 0x%X -0x%X with SIGFPE.", op, op1);
             //fatal("please update this code.");
         }
       } else if (sig == SIGSEGV &&
           !MacroAssembler::needs_explicit_null_check((intptr_t)info->si_addr)) {
 #ifdef PRINT_SIGNAL_HANDLE
         tty->print("continuation for implicit exception\n");
 #endif
         // Determination of interpreter/vtable stub/compiled code null exception
         stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_NULL);
 #ifdef PRINT_SIGNAL_HANDLE
         tty->print_cr("continuation_for_implicit_exception stub: %lx", stub);
 #endif
       } else if (/*thread->thread_state() == _thread_in_Java && */sig == SIGILL) {
         //Since kernel does not have emulation of PS instructions yet, the emulation must be handled here.
         //The method is to trigger kernel emulation of float emulation.
         int inst = *(int*)pc;
         int ops = (inst >> 26) & 0x3f;
         int ops_fmt = (inst >> 21) & 0x1f;
         int op = inst & 0x3f;
         if (ops == Assembler::cop1_op && ops_fmt == Assembler::ps_fmt) {
           int ft, fs, fd;
           ft = (inst >> 16) & 0x1f;
           fs = (inst >> 11) & 0x1f;
           fd = (inst >> 6) & 0x1f;
           float ft_upper, ft_lower, fs_upper, fs_lower, fd_upper, fd_lower;
           double ft_value, fs_value, fd_value;
           ft_value = uc->uc_mcontext.fpregs.fp_r.fp_dregs[ft];
           fs_value = uc->uc_mcontext.fpregs.fp_r.fp_dregs[fs];
           __asm__ __volatile__ (
             "cvt.s.pl %0, %4\n\t"
             "cvt.s.pu %1, %4\n\t"
             "cvt.s.pl %2, %5\n\t"
             "cvt.s.pu %3, %5\n\t"
             : "=f" (fs_lower), "=f" (fs_upper), "=f" (ft_lower), "=f" (ft_upper)
             : "f" (fs_value), "f" (ft_value)
           );
           switch (op) {
             case Assembler::fadd_op:
               __asm__ __volatile__ (
                 "add.s  %1, %3, %5\n\t"
                 "add.s  %2, %4, %6\n\t"
                 "pll.ps %0, %1, %2\n\t"
                 : "=f" (fd_value), "=f" (fd_upper), "=f" (fd_lower)
                 : "f" (fs_upper), "f" (fs_lower), "f" (ft_upper), "f" (ft_lower)
               );
               uc->uc_mcontext.fpregs.fp_r.fp_dregs[fd] = fd_value;
               stub = pc + 4;
               break;
             case Assembler::fsub_op:
               //fd = fs - ft
               __asm__ __volatile__ (
                 "sub.s  %1, %3, %5\n\t"
                 "sub.s  %2, %4, %6\n\t"
                 "pll.ps %0, %1, %2\n\t"
                 : "=f" (fd_value), "=f" (fd_upper), "=f" (fd_lower)
                 : "f" (fs_upper), "f" (fs_lower), "f" (ft_upper), "f" (ft_lower)
               );
               uc->uc_mcontext.fpregs.fp_r.fp_dregs[fd] = fd_value;
               stub = pc + 4;
               break;
             case Assembler::fmul_op:
               __asm__ __volatile__ (
                 "mul.s  %1, %3, %5\n\t"
                 "mul.s  %2, %4, %6\n\t"
                 "pll.ps %0, %1, %2\n\t"
                 : "=f" (fd_value), "=f" (fd_upper), "=f" (fd_lower)
                 : "f" (fs_upper), "f" (fs_lower), "f" (ft_upper), "f" (ft_lower)
               );
               uc->uc_mcontext.fpregs.fp_r.fp_dregs[fd] = fd_value;
               stub = pc + 4;
               break;
             default:
               tty->print_cr("unknown cop1 opcode 0x%x with SIGILL.", op);
           }
         } else if (ops == Assembler::cop1x_op /*&& op == Assembler::nmadd_ps_op*/) {
           // madd.ps is not used, the code below were not tested
           int fr, ft, fs, fd;
           float fr_upper, fr_lower, fs_upper, fs_lower, ft_upper, ft_lower, fd_upper, fd_lower;
           double fr_value, ft_value, fs_value, fd_value;
           switch (op) {
             case Assembler::madd_ps_op:
               // fd = (fs * ft) + fr
               fr = (inst >> 21) & 0x1f;
               ft = (inst >> 16) & 0x1f;
               fs = (inst >> 11) & 0x1f;
               fd = (inst >> 6) & 0x1f;
               fr_value = uc->uc_mcontext.fpregs.fp_r.fp_dregs[fr];
               ft_value = uc->uc_mcontext.fpregs.fp_r.fp_dregs[ft];
               fs_value = uc->uc_mcontext.fpregs.fp_r.fp_dregs[fs];
               __asm__ __volatile__ (
                 "cvt.s.pu %3, %9\n\t"
                 "cvt.s.pl %4, %9\n\t"
                 "cvt.s.pu %5, %10\n\t"
                 "cvt.s.pl %6, %10\n\t"
                 "cvt.s.pu %7, %11\n\t"
                 "cvt.s.pl %8, %11\n\t"
                 "madd.s %1, %3, %5, %7\n\t"
                 "madd.s %2, %4, %6, %8\n\t"
                 "pll.ps %0, %1, %2\n\t"
                 : "=f" (fd_value), "=f" (fd_upper), "=f" (fd_lower), "=f" (fr_upper), "=f" (fr_lower), "=f" (fs_upper), "=f" (fs_lower), "=f" (ft_upper), "=f" (ft_lower)
                 : "f" (fr_value)/*9*/, "f" (fs_value)/*10*/, "f" (ft_value)/*11*/
               );
               uc->uc_mcontext.fpregs.fp_r.fp_dregs[fd] = fd_value;
               stub = pc + 4;
               break;
             default:
               tty->print_cr("unknown cop1x opcode 0x%x with SIGILL.", op);
           }
         }
       } //SIGILL
     } else if (thread->thread_state() == _thread_in_vm &&
                sig == SIGBUS && /* info->si_code == BUS_OBJERR && */
                thread->doing_unsafe_access()) {
 #ifdef PRINT_SIGNAL_HANDLE
       tty->print_cr("SIGBUS in vm thread \n");
 #endif
       stub = StubRoutines::handler_for_unsafe_access();
     }
     // 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)) {
 #ifdef PRINT_SIGNAL_HANDLE
       tty->print("jni fast get trap: ");
 #endif
       address addr = JNI_FastGetField::find_slowcase_pc(pc);
       if (addr != (address)-1) {
         stub = addr;
       }
 #ifdef PRINT_SIGNAL_HANDLE
       tty->print_cr("addr = %d, stub = %lx", addr, stub);
 #endif
     }
     // 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)) {
 #ifdef PRINT_SIGNAL_HANDLE
       tty->print("write protecting the memory serialiazation page\n");
 #endif
       // Block current thread until the memory serialize page permission restored.
       os::block_on_serialize_page_trap();
       return true;
     }
   }
   // Execution protection violation
   //
   // This should be kept as the last step in the triage.  We don't
   // have a dedicated trap number for a no-execute fault, so be
   // conservative and allow other handlers the first shot.
   //
   // Note: We don't test that info->si_code == SEGV_ACCERR here.
   // this si_code is so generic that it is almost meaningless; and
   // the si_code for this condition may change in the future.
   // Furthermore, a false-positive should be harmless.
   if (UnguardOnExecutionViolation > 0 &&
       //(sig == SIGSEGV || sig == SIGBUS) &&
       //uc->uc_mcontext.gregs[REG_TRAPNO] == trap_page_fault) {
     (sig == SIGSEGV || sig == SIGBUS
 #ifdef OPT_RANGECHECK
      || sig == SIGSYS
 #endif
     ) &&
       //(uc->uc_mcontext.cause == 2 || uc->uc_mcontext.cause == 3)) {
       (uc->uc_mcontext.hi1 == 2 || uc->uc_mcontext.hi1 == 3)) {
 #ifdef PRINT_SIGNAL_HANDLE
     tty->print_cr("execution protection violation\n");
 #endif
     int page_size = os::vm_page_size();
     address addr = (address) info->si_addr;
     address pc = os::Linux::ucontext_get_pc(uc);
     // Make sure the pc and the faulting address are sane.
     //
     // If an instruction spans a page boundary, and the page containing
     // the beginning of the instruction is executable but the following
     // page is not, the pc and the faulting address might be slightly
     // different - we still want to unguard the 2nd page in this case.
     //
     // 15 bytes seems to be a (very) safe value for max instruction size.
     bool pc_is_near_addr =
       (pointer_delta((void*) addr, (void*) pc, sizeof(char)) < 15);
     bool instr_spans_page_boundary =
       (align_size_down((intptr_t) pc ^ (intptr_t) addr,
                        (intptr_t) page_size) > 0);
     if (pc == addr || (pc_is_near_addr && instr_spans_page_boundary)) {
       static volatile address last_addr =
         (address) os::non_memory_address_word();
       // In conservative mode, don't unguard unless the address is in the VM
       if (addr != last_addr &&
           (UnguardOnExecutionViolation > 1 || os::address_is_in_vm(addr))) {
         // Set memory to RWX and retry
         address page_start =
           (address) align_size_down((intptr_t) addr, (intptr_t) page_size);
         bool res = os::protect_memory((char*) page_start, page_size,
                                       os::MEM_PROT_RWX);
         if (PrintMiscellaneous && Verbose) {
           char buf[256];
           jio_snprintf(buf, sizeof(buf), "Execution protection violation "
                        "at " INTPTR_FORMAT
                        ", unguarding " INTPTR_FORMAT ": %s, errno=%d", addr,
                        page_start, (res ? "success" : "failed"), errno);
           tty->print_raw_cr(buf);
         }
         stub = pc;
         // Set last_addr so if we fault again at the same address, we don't end
         // up in an endless loop.
         //
         // There are two potential complications here.  Two threads trapping at
         // the same address at the same time could cause one of the threads to
         // think it already unguarded, and abort the VM.  Likely very rare.
         //
         // The other race involves two threads alternately trapping at
         // different addresses and failing to unguard the page, resulting in
         // an endless loop.  This condition is probably even more unlikely than
         // the first.
         //
         // Although both cases could be avoided by using locks or thread local
         // last_addr, these solutions are unnecessary complication: this
         // handler is a best-effort safety net, not a complete solution.  It is
         // disabled by default and should only be used as a workaround in case
         // we missed any no-execute-unsafe VM code.
         last_addr = addr;
       }
     }
   }
   if (stub != NULL) {
 #ifdef PRINT_SIGNAL_HANDLE
     tty->print_cr("resolved stub=%lx\n",stub);
 #endif
     // save all thread context in case we need to restore it
     if (thread != NULL) thread->set_saved_exception_pc(pc);
     uc->uc_mcontext.pc = (greg_t)stub;
     return true;
   }
   // signal-chaining
   if (os::Linux::chained_handler(sig, info, ucVoid)) {
 #ifdef PRINT_SIGNAL_HANDLE
      tty->print_cr("signal chaining\n");
 #endif
      return true;
   }
   if (!abort_if_unrecognized) {
 #ifdef PRINT_SIGNAL_HANDLE
     tty->print_cr("abort becauce of unrecognized\n");
 #endif
     // caller wants another chance, so give it to him
     return false;
   }
   if (pc == NULL && uc != NULL) {
     pc = os::Linux::ucontext_get_pc(uc);
   }
   // unmask current signal
   sigset_t newset;
   sigemptyset(&newset);
   sigaddset(&newset, sig);
   sigprocmask(SIG_UNBLOCK, &newset, NULL);
 #ifdef PRINT_SIGNAL_HANDLE
   tty->print_cr("VMError in signal handler\n");
 #endif
   VMError err(t, sig, pc, info, ucVoid);
   err.report_and_die();
   ShouldNotReachHere();
 }
 // FCSR:...|24| 23 |22|21|...
 //      ...|FS|FCC0|FO|FN|...
 void os::Linux::init_thread_fpu_state(void) {
   if (SetFSFOFN == 999)
     return;
   int fs = (SetFSFOFN / 100)? 1:0;
   int fo = ((SetFSFOFN % 100) / 10)? 1:0;
   int fn = (SetFSFOFN % 10)? 1:0;
   int mask = fs << 24 | fo << 22 | fn << 21;
   int fcsr = get_fpu_control_word();
   fcsr = fcsr | mask;
   set_fpu_control_word(fcsr);
   /*
   if (fcsr != get_fpu_control_word())
     tty->print_cr(" fail to set to %lx, get_fpu_control_word:%lx", fcsr, get_fpu_control_word());
   */
 }
 int os::Linux::get_fpu_control_word(void) {
   int fcsr;
   __asm__ __volatile__ (
       ".set noat;"
       "daddiu  %0, $0, 0;"
       "cfc1 %0, $31;"
       : "=r" (fcsr)
       );
   return fcsr;
 }
 void os::Linux::set_fpu_control_word(int fpu_control) {
   __asm__ __volatile__ (
       ".set noat;"
       "ctc1 %0, $31;"
       :
       : "r" (fpu_control)
       );
 }
 bool os::is_allocatable(size_t bytes) {
   if (bytes < 2 * G) {
     return true;
   }
   char* addr = reserve_memory(bytes, NULL);
   if (addr != NULL) {
     release_memory(addr, bytes);
   }
   return addr != NULL;
 }
 ////////////////////////////////////////////////////////////////////////////////
 // thread stack
 size_t os::Linux::min_stack_allowed  = 96 * K;
 // Test if pthread library can support variable thread stack size. LinuxThreads
 // in fixed stack mode allocates 2M fixed slot for each thread. LinuxThreads
 // in floating stack mode and NPTL support variable stack size.
 bool os::Linux::supports_variable_stack_size() {
   if (os::Linux::is_NPTL()) {
      // NPTL, yes
      return true;
   } else {
     // Note: We can't control default stack size when creating a thread.
     // If we use non-default stack size (pthread_attr_setstacksize), both
     // floating stack and non-floating stack LinuxThreads will return the
     // same value. This makes it impossible to implement this function by
     // detecting thread stack size directly.
     //
     // An alternative approach is to check %gs. Fixed-stack LinuxThreads
     // do not use %gs, so its value is 0. Floating-stack LinuxThreads use
     // %gs (either as LDT selector or GDT selector, depending on kernel)
     // to access thread specific data.
     //
     // Note that %gs is a reserved glibc register since early 2001, so
     // applications are not allowed to change its value (Ulrich Drepper from
     // Redhat confirmed that all known offenders have been modified to use
     // either %fs or TSD). In the worst case scenario, when VM is embedded in
     // a native application that plays with %gs, we might see non-zero %gs
     // even LinuxThreads is running in fixed stack mode. As the result, we'll
     // return true and skip _thread_safety_check(), so we may not be able to
     // detect stack-heap collisions. But otherwise it's harmless.
     //
     return false;
   }
 }
 // return default stack size for thr_type
 size_t os::Linux::default_stack_size(os::ThreadType thr_type) {
   // default stack size (compiler thread needs larger stack)
   size_t s = (thr_type == os::compiler_thread ? 2 * M : 512 * K);
   return s;
 }
 size_t os::Linux::default_guard_size(os::ThreadType thr_type) {
   // Creating guard page is very expensive. Java thread has HotSpot
   // guard page, only enable glibc guard page for non-Java threads.
   return (thr_type == java_thread ? 0 : page_size());
 }
 // Java thread:
 //
 //   Low memory addresses
 //    +------------------------+
 //    |                        |\  JavaThread created by VM does not have glibc
 //    |    glibc guard page    | - guard, attached Java thread usually has
 //    |                        |/  1 page glibc guard.
 // P1 +------------------------+ Thread::stack_base() - Thread::stack_size()
 //    |                        |\
 //    |  HotSpot Guard Pages   | - red and yellow pages
 //    |                        |/
 //    +------------------------+ JavaThread::stack_yellow_zone_base()
 //    |                        |\
 //    |      Normal Stack      | -
 //    |                        |/
 // P2 +------------------------+ Thread::stack_base()
 //
 // Non-Java thread:
 //
 //   Low memory addresses
 //    +------------------------+
 //    |                        |\
 //    |  glibc guard page      | - usually 1 page
 //    |                        |/
 // P1 +------------------------+ Thread::stack_base() - Thread::stack_size()
 //    |                        |\
 //    |      Normal Stack      | -
 //    |                        |/
 // P2 +------------------------+ Thread::stack_base()
 //
 // ** P1 (aka bottom) and size ( P2 = P1 - size) are the address and stack size returned from
 //    pthread_attr_getstack()
 static void current_stack_region(address * bottom, size_t * size) {
   if (os::Linux::is_initial_thread()) {
      // initial thread needs special handling because pthread_getattr_np()
      // may return bogus value.
      *bottom = os::Linux::initial_thread_stack_bottom();
      *size   = os::Linux::initial_thread_stack_size();
   } else {
      pthread_attr_t attr;
      int rslt = pthread_getattr_np(pthread_self(), &attr);
      // JVM needs to know exact stack location, abort if it fails
      if (rslt != 0) {
        if (rslt == ENOMEM) {
          vm_exit_out_of_memory(0, OOM_MMAP_ERROR, "pthread_getattr_np");
        } else {
          fatal(err_msg("pthread_getattr_np failed with errno = %d", rslt));
        }
      }
      if (pthread_attr_getstack(&attr, (void **)bottom, size) != 0) {
          fatal("Can not locate current stack attributes!");
      }
      pthread_attr_destroy(&attr);
   }
   assert(os::current_stack_pointer() >= *bottom &&
          os::current_stack_pointer() < *bottom + *size, "just checking");
 }
 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_register_info(outputStream *st, void *context) {
   if (context == NULL) return;
   ucontext_t *uc = (ucontext_t*)context;
   st->print_cr("Register to memory mapping:");
   st->cr();
   // this is horrendously verbose but the layout of the registers in the
   //   // context does not match how we defined our abstract Register set, so
   //     // we can't just iterate through the gregs area
   //
   //       // this is only for the "general purpose" registers
   st->print("R0=" ); print_location(st, uc->uc_mcontext.gregs[0]);
   st->print("AT=" ); print_location(st, uc->uc_mcontext.gregs[1]);
   st->print("V0=" ); print_location(st, uc->uc_mcontext.gregs[2]);
   st->print("V1=" ); print_location(st, uc->uc_mcontext.gregs[3]);
   st->cr();
   st->print("A0=" ); print_location(st, uc->uc_mcontext.gregs[4]);
   st->print("A1=" ); print_location(st, uc->uc_mcontext.gregs[5]);
   st->print("A2=" ); print_location(st, uc->uc_mcontext.gregs[6]);
   st->print("A3=" ); print_location(st, uc->uc_mcontext.gregs[7]);
   st->cr();
   st->print("A4=" ); print_location(st, uc->uc_mcontext.gregs[8]);
   st->print("A5=" ); print_location(st, uc->uc_mcontext.gregs[9]);
   st->print("A6=" ); print_location(st, uc->uc_mcontext.gregs[10]);
   st->print("A7=" ); print_location(st, uc->uc_mcontext.gregs[11]);
   st->cr();
   st->print("T0=" ); print_location(st, uc->uc_mcontext.gregs[12]);
   st->print("T1=" ); print_location(st, uc->uc_mcontext.gregs[13]);
   st->print("T2=" ); print_location(st, uc->uc_mcontext.gregs[14]);
   st->print("T3=" ); print_location(st, uc->uc_mcontext.gregs[15]);
   st->cr();
   st->print("S0=" ); print_location(st, uc->uc_mcontext.gregs[16]);
   st->print("S1=" ); print_location(st, uc->uc_mcontext.gregs[17]);
   st->print("S2=" ); print_location(st, uc->uc_mcontext.gregs[18]);
   st->print("S3=" ); print_location(st, uc->uc_mcontext.gregs[19]);
   st->cr();
   st->print("S4=" ); print_location(st, uc->uc_mcontext.gregs[20]);
   st->print("S5=" ); print_location(st, uc->uc_mcontext.gregs[21]);
   st->print("S6=" ); print_location(st, uc->uc_mcontext.gregs[22]);
   st->print("S7=" ); print_location(st, uc->uc_mcontext.gregs[23]);
   st->cr();
   st->print("T8=" ); print_location(st, uc->uc_mcontext.gregs[24]);
   st->print("T9=" ); print_location(st, uc->uc_mcontext.gregs[25]);
   st->print("K0=" ); print_location(st, uc->uc_mcontext.gregs[26]);
   st->print("K1=" ); print_location(st, uc->uc_mcontext.gregs[27]);
   st->cr();
   st->print("GP=" ); print_location(st, uc->uc_mcontext.gregs[28]);
   st->print("SP=" ); print_location(st, uc->uc_mcontext.gregs[29]);
   st->print("FP=" ); print_location(st, uc->uc_mcontext.gregs[30]);
   st->print("RA=" ); print_location(st, uc->uc_mcontext.gregs[31]);
   st->cr();
 }
 void os::print_context(outputStream *st, void *context) {
   if (context == NULL) return;
   ucontext_t *uc = (ucontext_t*)context;
   st->print_cr("Registers:");
   st->print(  "R0=" INTPTR_FORMAT, uc->uc_mcontext.gregs[0]);
   st->print(", AT=" INTPTR_FORMAT, uc->uc_mcontext.gregs[1]);
   st->print(", V0=" INTPTR_FORMAT, uc->uc_mcontext.gregs[2]);
   st->print(", V1=" INTPTR_FORMAT, uc->uc_mcontext.gregs[3]);
   st->cr();
   st->print(  "A0=" INTPTR_FORMAT, uc->uc_mcontext.gregs[4]);
   st->print(", A1=" INTPTR_FORMAT, uc->uc_mcontext.gregs[5]);
   st->print(", A2=" INTPTR_FORMAT, uc->uc_mcontext.gregs[6]);
   st->print(", A3=" INTPTR_FORMAT, uc->uc_mcontext.gregs[7]);
   st->cr();
   st->print(  "A4=" INTPTR_FORMAT, uc->uc_mcontext.gregs[8]);
   st->print(", A5=" INTPTR_FORMAT, uc->uc_mcontext.gregs[9]);
   st->print(", A6=" INTPTR_FORMAT, uc->uc_mcontext.gregs[10]);
   st->print(", A7=" INTPTR_FORMAT, uc->uc_mcontext.gregs[11]);
   st->cr();
   st->print(  "T0=" INTPTR_FORMAT, uc->uc_mcontext.gregs[12]);
   st->print(", T1=" INTPTR_FORMAT, uc->uc_mcontext.gregs[13]);
   st->print(", T2=" INTPTR_FORMAT, uc->uc_mcontext.gregs[14]);
   st->print(", T3=" INTPTR_FORMAT, uc->uc_mcontext.gregs[15]);
   st->cr();
   st->print(  "S0=" INTPTR_FORMAT, uc->uc_mcontext.gregs[16]);
   st->print(", S1=" INTPTR_FORMAT, uc->uc_mcontext.gregs[17]);
   st->print(", S2=" INTPTR_FORMAT, uc->uc_mcontext.gregs[18]);
   st->print(", S3=" INTPTR_FORMAT, uc->uc_mcontext.gregs[19]);
   st->cr();
   st->print(  "S4=" INTPTR_FORMAT, uc->uc_mcontext.gregs[20]);
   st->print(", S5=" INTPTR_FORMAT, uc->uc_mcontext.gregs[21]);
   st->print(", S6=" INTPTR_FORMAT, uc->uc_mcontext.gregs[22]);
   st->print(", S7=" INTPTR_FORMAT, uc->uc_mcontext.gregs[23]);
   st->cr();
   st->print(  "T8=" INTPTR_FORMAT, uc->uc_mcontext.gregs[24]);
   st->print(", T9=" INTPTR_FORMAT, uc->uc_mcontext.gregs[25]);
   st->print(", K0=" INTPTR_FORMAT, uc->uc_mcontext.gregs[26]);
   st->print(", K1=" INTPTR_FORMAT, uc->uc_mcontext.gregs[27]);
   st->cr();
   st->print(  "GP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[28]);
   st->print(", SP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[29]);
   st->print(", FP=" INTPTR_FORMAT, uc->uc_mcontext.gregs[30]);
   st->print(", RA=" INTPTR_FORMAT, uc->uc_mcontext.gregs[31]);
   st->cr();
   st->cr();
   intptr_t *sp = (intptr_t *)os::Linux::ucontext_get_sp(uc);
   st->print_cr("Top of Stack: (sp=" PTR_FORMAT ")", sp);
   //print_hex_dump(st, (address)sp, (address)(sp + 8*sizeof(intptr_t)), sizeof(intptr_t));
   print_hex_dump(st, (address)sp-32, (address)(sp + 32), sizeof(intptr_t));
   st->cr();
   // Note: it may be unsafe to inspect memory near pc. For example, pc may
   // point to garbage if entry point in an nmethod is corrupted. Leave
   // this at the end, and hope for the best.
   address pc = os::Linux::ucontext_get_pc(uc);
   st->print_cr("Instructions: (pc=" PTR_FORMAT ")", pc);
   print_hex_dump(st, pc - 64, pc + 64, sizeof(char));
   Disassembler::decode(pc - 80, pc + 80, st);
 }
 void os::setup_fpu() {
   /*
   //no use for MIPS
   int fcsr;
   address fpu_cntrl = StubRoutines::addr_fpu_cntrl_wrd_std();
   __asm__ __volatile__ (
       ".set noat;"
       "cfc1 %0, $31;"
       "sw   %0, 0(%1);"
       : "=r" (fcsr)
       : "r" (fpu_cntrl)
       : "memory"
   );
   printf("fpu_cntrl:  %lx\n", fpu_cntrl);
   */
 }
 #ifndef PRODUCT
 void os::verify_stack_alignment() {
   assert(((intptr_t)os::current_stack_pointer() & (StackAlignmentInBytes-1)) == 0, "incorrect stack alignment");
 }
 #endif

Mercurial > jdk8-mips64-public > hotspot / annotate

src/os_cpu/linux_mips/vm/os_linux_mips.cpp@1ccc5a3b3671 (annotated)

src/os_cpu/linux_mips/vm/os_linux_mips.cpp