thread_linux_x86.cpp revision 0:a61af66fc99e 
1/*
2 * Copyright 2003-2005 Sun Microsystems, Inc.  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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
20 * CA 95054 USA or visit www.sun.com if you need additional information or
21 * have any questions.
22 *
23 */
24
25#include "incls/_precompiled.incl"
26#include "incls/_thread_linux_x86.cpp.incl"
27
28// For Forte Analyzer AsyncGetCallTrace profiling support - thread is
29// currently interrupted by SIGPROF
30bool JavaThread::pd_get_top_frame_for_signal_handler(frame* fr_addr,
31  void* ucontext, bool isInJava) {
32
33  assert(Thread::current() == this, "caller must be current thread");
34  assert(this->is_Java_thread(), "must be JavaThread");
35
36  JavaThread* jt = (JavaThread *)this;
37
38  // If we have a last_Java_frame, then we should use it even if
39  // isInJava == true.  It should be more reliable than ucontext info.
40  if (jt->has_last_Java_frame()) {
41    *fr_addr = jt->pd_last_frame();
42    return true;
43  }
44
45  // At this point, we don't have a last_Java_frame, so
46  // we try to glean some information out of the ucontext
47  // if we were running Java code when SIGPROF came in.
48  if (isInJava) {
49    ucontext_t* uc = (ucontext_t*) ucontext;
50
51    intptr_t* ret_fp;
52    intptr_t* ret_sp;
53    ExtendedPC addr = os::Linux::fetch_frame_from_ucontext(this, uc,
54      &ret_sp, &ret_fp);
55    if (addr.pc() == NULL || ret_sp == NULL ) {
56      // ucontext wasn't useful
57      return false;
58    }
59
60    frame ret_frame(ret_sp, ret_fp, addr.pc());
61    if (!ret_frame.safe_for_sender(jt)) {
62#ifdef COMPILER2
63      // C2 uses ebp as a general register see if NULL fp helps
64      frame ret_frame2(ret_sp, NULL, addr.pc());
65      if (!ret_frame2.safe_for_sender(jt)) {
66        // nothing else to try if the frame isn't good
67        return false;
68      }
69      ret_frame = ret_frame2;
70#else
71      // nothing else to try if the frame isn't good
72      return false;
73#endif /* COMPILER2 */
74    }
75    *fr_addr = ret_frame;
76    return true;
77  }
78
79  // nothing else to try
80  return false;
81}
82