thread_linux_sparc.cpp revision 10844:c04ff0bb5b8e 
1/*
2 * Copyright (c) 2003, 2010, 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,
34                                                     bool isInJava) {
35  assert(Thread::current() == this, "caller must be current thread");
36  assert(this->is_Java_thread(), "must be JavaThread");
37
38  JavaThread* jt = (JavaThread *)this;
39
40  if (!isInJava) {
41    // make_walkable flushes register windows and grabs last_Java_pc
42    // which can not be done if the ucontext sp matches last_Java_sp
43    // stack walking utilities assume last_Java_pc set if marked flushed
44    jt->frame_anchor()->make_walkable(jt);
45  }
46
47  // If we have a walkable last_Java_frame, then we should use it
48  // even if isInJava == true. It should be more reliable than
49  // ucontext info.
50  if (jt->has_last_Java_frame() && jt->frame_anchor()->walkable()) {
51    *fr_addr = jt->pd_last_frame();
52    return true;
53  }
54
55  ucontext_t* uc = (ucontext_t*) ucontext;
56
57  // At this point, we don't have a walkable last_Java_frame, so
58  // we try to glean some information out of the ucontext.
59  intptr_t* ret_sp;
60  ExtendedPC addr =
61    os::fetch_frame_from_context(uc, &ret_sp,
62                                 NULL /* ret_fp only used on X86 */);
63  if (addr.pc() == NULL || ret_sp == NULL) {
64    // ucontext wasn't useful
65    return false;
66  }
67
68#if INCLUDE_CDS
69  if (UseSharedSpaces && MetaspaceShared::is_in_shared_region(addr.pc(), MetaspaceShared::md)) {
70    // In the middle of a trampoline call. Bail out for safety.
71    // This happens rarely so shouldn't affect profiling.
72    return false;
73  }
74#endif
75
76  // we were running Java code when SIGPROF came in
77  if (isInJava) {
78    // If we have a last_Java_sp, then the SIGPROF signal caught us
79    // right when we were transitioning from _thread_in_Java to a new
80    // JavaThreadState. We use last_Java_sp instead of the sp from
81    // the ucontext since it should be more reliable.
82    if (jt->has_last_Java_frame()) {
83      ret_sp = jt->last_Java_sp();
84    }
85    // Implied else: we don't have a last_Java_sp so we use what we
86    // got from the ucontext.
87
88    frame ret_frame(ret_sp, frame::unpatchable, addr.pc());
89    if (!ret_frame.safe_for_sender(jt)) {
90      // nothing else to try if the frame isn't good
91      return false;
92    }
93    *fr_addr = ret_frame;
94    return true;
95  }
96
97  // At this point, we know we weren't running Java code. We might
98  // have a last_Java_sp, but we don't have a walkable frame.
99  // However, we might still be able to construct something useful
100  // if the thread was running native code.
101  if (jt->has_last_Java_frame()) {
102    assert(!jt->frame_anchor()->walkable(), "case covered above");
103
104    if (jt->thread_state() == _thread_in_native) {
105      frame ret_frame(jt->last_Java_sp(), frame::unpatchable, addr.pc());
106      if (!ret_frame.safe_for_sender(jt)) {
107        // nothing else to try if the frame isn't good
108        return false;
109      }
110      *fr_addr = ret_frame;
111      return true;
112    }
113  }
114
115  // nothing else to try
116  return false;
117}
118
119void JavaThread::cache_global_variables() { }
120
121