1 /*
   2  * Copyright (c) 2003, 2018, Oracle and/or its affiliates. All rights reserved.
   3  * Copyright (c) 2014, Red Hat Inc. All rights reserved.
   4  * Copyright (c) 2015, Linaro Ltd. All rights reserved.
   5  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   6  *
   7  * This code is free software; you can redistribute it and/or modify it
   8  * under the terms of the GNU General Public License version 2 only, as
   9  * published by the Free Software Foundation.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  *
  25  */
  26 
  27 #include "precompiled.hpp"
  28 #include "memory/metaspaceShared.hpp"
  29 #include "runtime/frame.inline.hpp"
  30 #include "runtime/thread.inline.hpp"
  31 
  32 frame JavaThread::pd_last_frame() {
  33   assert(has_last_Java_frame(), "must have last_Java_sp() when suspended");
  34   return frame(_anchor.last_Java_sp(), _anchor.last_Java_fp(), _anchor.last_Java_pc());
  35 }
  36 
  37 // For Forte Analyzer AsyncGetCallTrace profiling support - thread is
  38 // currently interrupted by SIGPROF
  39 bool JavaThread::pd_get_top_frame_for_signal_handler(frame* fr_addr,
  40   void* ucontext, bool isInJava) {
  41 
  42   assert(Thread::current() == this, "caller must be current thread");
  43   return pd_get_top_frame(fr_addr, ucontext, isInJava);
  44 }
  45 
  46 bool JavaThread::pd_get_top_frame_for_profiling(frame* fr_addr, void* ucontext, bool isInJava) {
  47   return pd_get_top_frame(fr_addr, ucontext, isInJava);
  48 }
  49 
  50 bool JavaThread::pd_get_top_frame(frame* fr_addr, void* ucontext, bool isInJava) {
  51   assert(this->is_Java_thread(), "must be JavaThread");
  52   JavaThread* jt = (JavaThread *)this;
  53 
  54   // If we have a last_Java_frame, then we should use it even if
  55   // isInJava == true.  It should be more reliable than ucontext info.
  56   if (jt->has_last_Java_frame() && jt->frame_anchor()->walkable()) {
  57     *fr_addr = jt->pd_last_frame();
  58     return true;
  59   }
  60 
  61   // At this point, we don't have a last_Java_frame, so
  62   // we try to glean some information out of the ucontext
  63   // if we were running Java code when SIGPROF came in.
  64   if (isInJava) {
  65     ucontext_t* uc = (ucontext_t*) ucontext;
  66 
  67     intptr_t* ret_fp;
  68     intptr_t* ret_sp;
  69     ExtendedPC addr = os::Linux::fetch_frame_from_ucontext(this, uc,
  70       &ret_sp, &ret_fp);
  71     if (addr.pc() == NULL || ret_sp == NULL ) {
  72       // ucontext wasn't useful
  73       return false;
  74     }
  75 
  76     if (MetaspaceShared::is_in_trampoline_frame(addr.pc())) {
  77       // In the middle of a trampoline call. Bail out for safety.
  78       // This happens rarely so shouldn't affect profiling.
  79       return false;
  80     }
  81 
  82     frame ret_frame(ret_sp, ret_fp, addr.pc());
  83     if (!ret_frame.safe_for_sender(jt)) {
  84 #ifdef COMPILER2
  85       frame ret_frame2(ret_sp, NULL, addr.pc());
  86       if (!ret_frame2.safe_for_sender(jt)) {
  87         // nothing else to try if the frame isn't good
  88         return false;
  89       }
  90       ret_frame = ret_frame2;
  91 #else
  92       // nothing else to try if the frame isn't good
  93       return false;
  94 #endif /* COMPILER2 */
  95     }
  96     *fr_addr = ret_frame;
  97     return true;
  98   }
  99 
 100   // nothing else to try
 101   return false;
 102 }
 103 
 104 void JavaThread::cache_global_variables() { }
 105