1 /* 2 * Copyright (c) 2018, 2019, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 */ 23 24 #include "precompiled.hpp" 25 #include "code/nmethod.hpp" 26 #include "gc/z/zBarrierSetNMethod.hpp" 27 #include "gc/z/zGlobals.hpp" 28 #include "gc/z/zLock.inline.hpp" 29 #include "gc/z/zOopClosures.hpp" 30 #include "gc/z/zNMethod.hpp" 31 #include "gc/z/zThreadLocalData.hpp" 32 #include "logging/log.hpp" 33 34 bool ZBarrierSetNMethod::nmethod_entry_barrier(nmethod* nm) { 35 ZLocker<ZReentrantLock> locker(ZNMethod::lock_for_nmethod(nm)); 36 log_trace(nmethod, barrier)("Entered critical zone for %p", nm); 37 38 if (!is_armed(nm)) { 39 // Some other thread got here first and healed the oops 40 // and disarmed the nmethod. 41 return true; 42 } 43 44 if (nm->is_unloading()) { 45 // We don't need to take the lock when unlinking nmethods from 46 // the Method, because it is only concurrently unlinked by 47 // the entry barrier, which acquires the per nmethod lock. 48 nm->unlink_from_method(); 49 50 // We can end up calling nmethods that are unloading 51 // since we clear compiled ICs lazily. Returning false 52 // will re-resovle the call and update the compiled IC. 53 return false; 54 } 55 56 // Heal oops and disarm 57 ZNMethodOopClosure cl; 58 ZNMethod::nmethod_oops_do(nm, &cl); 59 disarm(nm); 60 61 return true; 62 } 63 64 int* ZBarrierSetNMethod::disarmed_value_address() const { 65 const uintptr_t mask_addr = reinterpret_cast<uintptr_t>(&ZAddressBadMask); 66 const uintptr_t disarmed_addr = mask_addr + ZNMethodDisarmedOffset; 67 return reinterpret_cast<int*>(disarmed_addr); 68 } 69 70 ByteSize ZBarrierSetNMethod::thread_disarmed_offset() const { 71 return ZThreadLocalData::nmethod_disarmed_offset(); 72 }