1 /* 2 * Copyright (c) 2008, 2016, 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 25 #include "precompiled.hpp" 26 #include "gc/shared/barrierSet.inline.hpp" 27 #include "gc/shared/cardTableModRefBS.inline.hpp" 28 #include "gc/shared/collectedHeap.hpp" 29 #include "memory/metaspaceShared.hpp" 30 #include "runtime/frame.inline.hpp" 31 32 void JavaThread::cache_global_variables() { 33 BarrierSet* bs = Universe::heap()->barrier_set(); 34 35 const bool allow_shared_alloc = 36 Universe::heap()->supports_inline_contig_alloc(); 37 38 if (allow_shared_alloc) { 39 _heap_top_addr = (address) Universe::heap()->top_addr(); 40 } else { 41 _heap_top_addr = NULL; 42 } 43 44 if (bs->is_a(BarrierSet::CardTableModRef)) { 45 _card_table_base = (address) (barrier_set_cast<CardTableModRefBS>(bs)->byte_map_base); 46 } else { 47 _card_table_base = NULL; 48 } 49 50 } 51 52 // For Forte Analyzer AsyncGetCallTrace profiling support - thread is 53 // currently interrupted by SIGPROF 54 bool JavaThread::pd_get_top_frame_for_signal_handler(frame* fr_addr, 55 void* ucontext, bool isInJava) { 56 assert(Thread::current() == this, "caller must be current thread"); 57 return pd_get_top_frame(fr_addr, ucontext, isInJava); 58 } 59 60 bool JavaThread::pd_get_top_frame_for_profiling(frame* fr_addr, void* ucontext, bool isInJava) { 61 return pd_get_top_frame(fr_addr, ucontext, isInJava); 62 } 63 64 bool JavaThread::pd_get_top_frame(frame* fr_addr, void* ucontext, bool isInJava) { 65 assert(this->is_Java_thread(), "must be JavaThread"); 66 67 JavaThread* jt = (JavaThread *)this; 68 69 // If we have a last_Java_frame, then we should use it even if 70 // isInJava == true. It should be more reliable than ucontext info. 71 if (jt->has_last_Java_frame() AARCH64_ONLY(&& jt->last_Java_pc() != NULL)) { 72 *fr_addr = jt->pd_last_frame(); 73 return true; 74 } 75 76 // Could be in a code section that plays with the stack, like 77 // MacroAssembler::verify_heapbase() 78 if (jt->in_top_frame_unsafe_section()) { 79 return false; 80 } 81 82 // At this point, we don't have a last_Java_frame, so 83 // we try to glean some information out of the ucontext 84 // if we were running Java code when SIGPROF came in. 85 if (isInJava) { 86 ucontext_t* uc = (ucontext_t*) ucontext; 87 88 intptr_t* ret_fp; 89 intptr_t* ret_sp; 90 ExtendedPC addr = os::Linux::fetch_frame_from_ucontext(this, uc, 91 &ret_sp, &ret_fp); 92 if (addr.pc() == NULL || ret_sp == NULL ) { 93 // ucontext wasn't useful 94 return false; 95 } 96 97 #if INCLUDE_CDS 98 if (UseSharedSpaces && MetaspaceShared::is_in_shared_region(addr.pc(), MetaspaceShared::md)) { 99 // In the middle of a trampoline call. Bail out for safety. 100 // This happens rarely so shouldn't affect profiling. 101 return false; 102 } 103 #endif 104 105 frame ret_frame(ret_sp, ret_fp, addr.pc()); 106 if (!ret_frame.safe_for_sender(jt)) { 107 #ifdef COMPILER2 108 // C2 uses ebp as a general register see if NULL fp helps 109 frame ret_frame2(ret_sp, NULL, addr.pc()); 110 if (!ret_frame2.safe_for_sender(jt)) { 111 // nothing else to try if the frame isn't good 112 return false; 113 } 114 ret_frame = ret_frame2; 115 #else 116 // nothing else to try if the frame isn't good 117 return false; 118 #endif /* COMPILER2 */ 119 } 120 *fr_addr = ret_frame; 121 return true; 122 } 123 124 // nothing else to try 125 return false; 126 }