1 /*
  2  * Copyright (c) 2003, 2020, 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 "memory/metaspaceShared.hpp"
 27 #include "runtime/frame.inline.hpp"
 28 #include "runtime/thread.inline.hpp"
 29 
 30 frame JavaThread::pd_last_frame() {
 31   assert(has_last_Java_frame(), "must have last_Java_sp() when suspended");
 32   vmassert(_anchor.last_Java_pc() != NULL, "not walkable");
 33   return frame(_anchor.last_Java_sp(), _anchor.last_Java_fp(), _anchor.last_Java_pc());
 34 }
 35 
 36 // For Forte Analyzer AsyncGetCallTrace profiling support - thread is
 37 // currently interrupted by SIGPROF
 38 bool JavaThread::pd_get_top_frame_for_signal_handler(frame* fr_addr,
 39   void* ucontext, bool isInJava) {
 40 
 41   assert(Thread::current() == this, "caller must be current thread");
 42   return pd_get_top_frame(fr_addr, ucontext, isInJava);
 43 }
 44 
 45 bool JavaThread::pd_get_top_frame_for_profiling(frame* fr_addr, void* ucontext, bool isInJava) {
 46   return pd_get_top_frame(fr_addr, ucontext, isInJava);
 47 }
 48 
 49 bool JavaThread::pd_get_top_frame(frame* fr_addr, void* ucontext, bool isInJava) {
 50 
 51   assert(this->is_Java_thread(), "must be JavaThread");
 52 
 53   JavaThread* jt = (JavaThread *)this;
 54 
 55   // If we have a last_Java_frame, then we should use it even if
 56   // isInJava == true.  It should be more reliable than CONTEXT info.
 57   if (jt->has_last_Java_frame() && jt->frame_anchor()->walkable()) {
 58     *fr_addr = jt->pd_last_frame();
 59     return true;
 60   }
 61 
 62   // At this point, we don't have a last_Java_frame, so
 63   // we try to glean some information out of the CONTEXT
 64   // if we were running Java code when SIGPROF came in.
 65   if (isInJava) {
 66     CONTEXT* uc = (CONTEXT*)ucontext;
 67 
 68 #ifdef AMD64
 69     intptr_t* ret_fp = (intptr_t*) uc->Rbp;
 70     intptr_t* ret_sp = (intptr_t*) uc->Rsp;
 71     address addr = (address)uc->Rip;
 72 #else
 73     intptr_t* ret_fp = (intptr_t*) uc->Ebp;
 74     intptr_t* ret_sp = (intptr_t*) uc->Esp;
 75     address addr = (address)uc->Eip;
 76 #endif // AMD64
 77     if (addr == NULL || ret_sp == NULL ) {
 78       // CONTEXT wasn't useful
 79       return false;
 80     }
 81 
 82     if (MetaspaceShared::is_in_trampoline_frame(addr)) {
 83       // In the middle of a trampoline call. Bail out for safety.
 84       // This happens rarely so shouldn't affect profiling.
 85       return false;
 86     }
 87 
 88     frame ret_frame(ret_sp, ret_fp, addr);
 89     if (!ret_frame.safe_for_sender(jt)) {
 90 #if COMPILER2_OR_JVMCI
 91       // C2 and JVMCI use ebp as a general register see if NULL fp helps
 92       frame ret_frame2(ret_sp, NULL, addr);
 93       if (!ret_frame2.safe_for_sender(jt)) {
 94         // nothing else to try if the frame isn't good
 95         return false;
 96       }
 97       ret_frame = ret_frame2;
 98 #else
 99       // nothing else to try if the frame isn't good
100       return false;
101 #endif // COMPILER2_OR_JVMCI
102     }
103     *fr_addr = ret_frame;
104     return true;
105   }
106 
107   // nothing else to try
108   return false;
109 }
110 
111 void JavaThread::cache_global_variables() { }