1 /*
   2  * Copyright (c) 1997, 2018, Oracle and/or its affiliates. All rights reserved.
   3  * Copyright (c) 2012, 2014 SAP SE. All rights reserved.
   4  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   5  *
   6  * This code is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU General Public License version 2 only, as
   8  * published by the Free Software Foundation.
   9  *
  10  * This code is distributed in the hope that it will be useful, but WITHOUT
  11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  13  * version 2 for more details (a copy is included in the LICENSE file that
  14  * accompanied this code).
  15  *
  16  * You should have received a copy of the GNU General Public License version
  17  * 2 along with this work; if not, write to the Free Software Foundation,
  18  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  19  *
  20  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  21  * or visit www.oracle.com if you need additional information or have any
  22  * questions.
  23  *
  24  */
  25 
  26 #include "precompiled.hpp"
  27 #include "runtime/frame.inline.hpp"
  28 #include "runtime/thread.hpp"
  29 
  30 frame JavaThread::pd_last_frame() {
  31   assert(has_last_Java_frame(), "must have last_Java_sp() when suspended");
  32 
  33   intptr_t* sp = last_Java_sp();
  34   address pc = _anchor.last_Java_pc();
  35 
  36   // Last_Java_pc ist not set, if we come here from compiled code.
  37   if (pc == NULL) {
  38     pc = (address) *(sp + 2);
  39   }
  40 
  41   return frame(sp, pc);
  42 }
  43 
  44 bool JavaThread::pd_get_top_frame_for_profiling(frame* fr_addr, void* ucontext, bool isInJava) {
  45   assert(this->is_Java_thread(), "must be JavaThread");
  46 
  47   // If we have a last_Java_frame, then we should use it even if
  48   // isInJava == true.  It should be more reliable than ucontext info.
  49   if (has_last_Java_frame() && frame_anchor()->walkable()) {
  50     *fr_addr = pd_last_frame();
  51     return true;
  52   }
  53 
  54   // At this point, we don't have a last_Java_frame, so
  55   // we try to glean some information out of the ucontext
  56   // if we were running Java code when SIGPROF came in.
  57   if (isInJava) {
  58     ucontext_t* uc = (ucontext_t*) ucontext;
  59     frame ret_frame((intptr_t*)uc->uc_mcontext.regs->gpr[1/*REG_SP*/],
  60                      (address)uc->uc_mcontext.regs->nip);
  61 
  62     if (ret_frame.pc() == NULL) {
  63       // ucontext wasn't useful
  64       return false;
  65     }
  66 
  67     if (ret_frame.is_interpreted_frame()) {
  68        frame::ijava_state* istate = ret_frame.get_ijava_state();
  69        if (!((Method*)(istate->method))->is_metaspace_object()) {
  70          return false;
  71        }
  72        uint64_t reg_bcp = uc->uc_mcontext.regs->gpr[14/*R14_bcp*/];
  73        uint64_t istate_bcp = istate->bcp;
  74        uint64_t code_start = (uint64_t)(((Method*)(istate->method))->code_base());
  75        uint64_t code_end = (uint64_t)(((Method*)istate->method)->code_base() + ((Method*)istate->method)->code_size());
  76        if (istate_bcp >= code_start && istate_bcp < code_end) {
  77          // we have a valid bcp, don't touch it, do nothing
  78        } else if (reg_bcp >= code_start && reg_bcp < code_end) {
  79          istate->bcp = reg_bcp;
  80       } else {
  81          return false;
  82        }
  83     }
  84     if (!ret_frame.safe_for_sender(this)) {
  85       // nothing else to try if the frame isn't good
  86       return false;
  87     }
  88     *fr_addr = ret_frame;
  89     return true;
  90   }
  91   // nothing else to try
  92   return false;
  93 }
  94 
  95 // Forte Analyzer AsyncGetCallTrace profiling support is not implemented on Linux/PPC.
  96 bool JavaThread::pd_get_top_frame_for_signal_handler(frame* fr_addr, void* ucontext, bool isInJava) {
  97   assert(this->is_Java_thread(), "must be JavaThread");
  98   return pd_get_top_frame_for_profiling(fr_addr, ucontext, isInJava);
  99 }
 100 
 101 void JavaThread::cache_global_variables() { }