thread_linux_arm.cpp revision 13370:731370f39fcd 
1/*
2 * Copyright (c) 2008, 2017, 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 "gc/shared/barrierSet.inline.hpp"
27#include "gc/shared/cardTableModRefBS.inline.hpp"
28#include "gc/shared/collectedHeap.hpp"
29#include "memory/metaspaceShared.hpp"
30#include "runtime/frame.inline.hpp"
31
32void JavaThread::cache_global_variables() {
33  BarrierSet* bs = Universe::heap()->barrier_set();
34
35  const bool allow_shared_alloc =
36    Universe::heap()->supports_inline_contig_alloc();
37
38  if (allow_shared_alloc) {
39    _heap_top_addr = (address) Universe::heap()->top_addr();
40  } else {
41    _heap_top_addr = NULL;
42  }
43
44  if (bs->is_a(BarrierSet::CardTableModRef)) {
45    _card_table_base = (address) (barrier_set_cast<CardTableModRefBS>(bs)->byte_map_base);
46  } else {
47    _card_table_base = NULL;
48  }
49
50}
51
52// For Forte Analyzer AsyncGetCallTrace profiling support - thread is
53// currently interrupted by SIGPROF
54bool JavaThread::pd_get_top_frame_for_signal_handler(frame* fr_addr,
55  void* ucontext, bool isInJava) {
56  assert(Thread::current() == this, "caller must be current thread");
57  return pd_get_top_frame(fr_addr, ucontext, isInJava);
58}
59
60bool JavaThread::pd_get_top_frame_for_profiling(frame* fr_addr, void* ucontext, bool isInJava) {
61  return pd_get_top_frame(fr_addr, ucontext, isInJava);
62}
63
64bool JavaThread::pd_get_top_frame(frame* fr_addr, void* ucontext, bool isInJava) {
65  assert(this->is_Java_thread(), "must be JavaThread");
66
67  JavaThread* jt = (JavaThread *)this;
68
69  // If we have a last_Java_frame, then we should use it even if
70  // isInJava == true.  It should be more reliable than ucontext info.
71  if (jt->has_last_Java_frame() AARCH64_ONLY(&& jt->last_Java_pc() != NULL)) {
72    *fr_addr = jt->pd_last_frame();
73    return true;
74  }
75
76  // Could be in a code section that plays with the stack, like
77  // MacroAssembler::verify_heapbase()
78  if (jt->in_top_frame_unsafe_section()) {
79    return false;
80  }
81
82  // At this point, we don't have a last_Java_frame, so
83  // we try to glean some information out of the ucontext
84  // if we were running Java code when SIGPROF came in.
85  if (isInJava) {
86    ucontext_t* uc = (ucontext_t*) ucontext;
87
88    intptr_t* ret_fp;
89    intptr_t* ret_sp;
90    ExtendedPC addr = os::Linux::fetch_frame_from_ucontext(this, uc,
91      &ret_sp, &ret_fp);
92    if (addr.pc() == NULL || ret_sp == NULL ) {
93      // ucontext wasn't useful
94      return false;
95    }
96
97    if (MetaspaceShared::is_in_trampoline_frame(addr.pc())) {
98      // In the middle of a trampoline call. Bail out for safety.
99      // This happens rarely so shouldn't affect profiling.
100      return false;
101    }
102
103    frame ret_frame(ret_sp, ret_fp, addr.pc());
104    if (!ret_frame.safe_for_sender(jt)) {
105#ifdef COMPILER2
106      // C2 uses ebp as a general register see if NULL fp helps
107      frame ret_frame2(ret_sp, NULL, addr.pc());
108      if (!ret_frame2.safe_for_sender(jt)) {
109        // nothing else to try if the frame isn't good
110        return false;
111      }
112      ret_frame = ret_frame2;
113#else
114      // nothing else to try if the frame isn't good
115      return false;
116#endif /* COMPILER2 */
117    }
118    *fr_addr = ret_frame;
119    return true;
120  }
121
122  // nothing else to try
123  return false;
124}
125