thread_linux_x86.cpp revision 11846:ef326749824a 
1/*
2 * Copyright (c) 2003, 2013, 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// For Forte Analyzer AsyncGetCallTrace profiling support - thread is
31// currently interrupted by SIGPROF
32bool JavaThread::pd_get_top_frame_for_signal_handler(frame* fr_addr,
33  void* ucontext, bool isInJava) {
34
35  assert(Thread::current() == this, "caller must be current thread");
36  return pd_get_top_frame(fr_addr, ucontext, isInJava);
37}
38
39bool JavaThread::pd_get_top_frame_for_profiling(frame* fr_addr, void* ucontext, bool isInJava) {
40  return pd_get_top_frame(fr_addr, ucontext, isInJava);
41}
42
43bool JavaThread::pd_get_top_frame(frame* fr_addr, void* ucontext, bool isInJava) {
44  assert(this->is_Java_thread(), "must be JavaThread");
45  JavaThread* jt = (JavaThread *)this;
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 (jt->has_last_Java_frame() && jt->frame_anchor()->walkable()) {
50    *fr_addr = jt->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
60    intptr_t* ret_fp;
61    intptr_t* ret_sp;
62    ExtendedPC addr = os::Linux::fetch_frame_from_ucontext(this, uc,
63      &ret_sp, &ret_fp);
64    if (addr.pc() == NULL || ret_sp == NULL ) {
65      // ucontext wasn't useful
66      return false;
67    }
68
69#if INCLUDE_CDS
70    if (UseSharedSpaces && MetaspaceShared::is_in_shared_region(addr.pc(), MetaspaceShared::md)) {
71      // In the middle of a trampoline call. Bail out for safety.
72      // This happens rarely so shouldn't affect profiling.
73      return false;
74    }
75#endif
76
77    frame ret_frame(ret_sp, ret_fp, addr.pc());
78    if (!ret_frame.safe_for_sender(jt)) {
79#if defined(COMPILER2) || INCLUDE_JVMCI
80      // C2 and JVMCI use ebp as a general register see if NULL fp helps
81      frame ret_frame2(ret_sp, NULL, addr.pc());
82      if (!ret_frame2.safe_for_sender(jt)) {
83        // nothing else to try if the frame isn't good
84        return false;
85      }
86      ret_frame = ret_frame2;
87#else
88      // nothing else to try if the frame isn't good
89      return false;
90#endif /* COMPILER2 || INCLUDE_JVMCI */
91    }
92    *fr_addr = ret_frame;
93    return true;
94  }
95
96  // nothing else to try
97  return false;
98}
99
100void JavaThread::cache_global_variables() { }
101
102