1 /* 2 * Copyright (c) 2003, 2010, 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 "runtime/frame.inline.hpp" 27 #include "runtime/thread.inline.hpp" 28 29 // For Forte Analyzer AsyncGetCallTrace profiling support - thread is 30 // currently interrupted by SIGPROF 31 bool JavaThread::pd_get_top_frame_for_signal_handler(frame* fr_addr, 32 void* ucontext, 33 bool isInJava) { 34 assert(Thread::current() == this, "caller must be current thread"); 35 assert(this->is_Java_thread(), "must be JavaThread"); 36 37 JavaThread* jt = (JavaThread *)this; 38 39 if (!isInJava) { 40 // make_walkable flushes register windows and grabs last_Java_pc 41 // which can not be done if the ucontext sp matches last_Java_sp 42 // stack walking utilities assume last_Java_pc set if marked flushed 43 jt->frame_anchor()->make_walkable(jt); 44 } 45 46 // If we have a walkable last_Java_frame, then we should use it 47 // even if isInJava == true. It should be more reliable than 48 // ucontext info. 49 if (jt->has_last_Java_frame() && jt->frame_anchor()->walkable()) { 50 *fr_addr = jt->pd_last_frame(); 51 return true; 52 } 53 54 ucontext_t* uc = (ucontext_t*) ucontext; 55 56 // At this point, we don't have a walkable last_Java_frame, so 57 // we try to glean some information out of the ucontext. 58 intptr_t* ret_sp; 59 ExtendedPC addr = 60 os::fetch_frame_from_context(uc, &ret_sp, 61 NULL /* ret_fp only used on X86 */); 62 if (addr.pc() == NULL || ret_sp == NULL) { 63 // ucontext wasn't useful 64 return false; 65 } 66 67 // we were running Java code when SIGPROF came in 68 if (isInJava) { 69 // If we have a last_Java_sp, then the SIGPROF signal caught us 70 // right when we were transitioning from _thread_in_Java to a new 71 // JavaThreadState. We use last_Java_sp instead of the sp from 72 // the ucontext since it should be more reliable. 73 if (jt->has_last_Java_frame()) { 74 ret_sp = jt->last_Java_sp(); 75 } 76 // Implied else: we don't have a last_Java_sp so we use what we 77 // got from the ucontext. 78 79 frame ret_frame(ret_sp, frame::unpatchable, addr.pc()); 80 if (!ret_frame.safe_for_sender(jt)) { 81 // nothing else to try if the frame isn't good 82 return false; 83 } 84 *fr_addr = ret_frame; 85 return true; 86 } 87 88 // At this point, we know we weren't running Java code. We might 89 // have a last_Java_sp, but we don't have a walkable frame. 90 // However, we might still be able to construct something useful 91 // if the thread was running native code. 92 if (jt->has_last_Java_frame()) { 93 assert(!jt->frame_anchor()->walkable(), "case covered above"); 94 95 if (jt->thread_state() == _thread_in_native) { 96 frame ret_frame(jt->last_Java_sp(), frame::unpatchable, addr.pc()); 97 if (!ret_frame.safe_for_sender(jt)) { 98 // nothing else to try if the frame isn't good 99 return false; 100 } 101 *fr_addr = ret_frame; 102 return true; 103 } 104 } 105 106 // nothing else to try 107 return false; 108 } 109 110 void JavaThread::cache_global_variables() { } 111