1/*
2 * Copyright (c) 2012, 2019, 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 "code/debugInfoRec.hpp"
27#include "code/nmethod.hpp"
28#include "code/pcDesc.hpp"
29#include "jfr/periodic/sampling/jfrCallTrace.hpp"
30#include "jfr/utilities/jfrTypes.hpp"
31#include "oops/method.hpp"
32#include "runtime/javaCalls.hpp"
33#include "runtime/frame.inline.hpp"
34#include "runtime/registerMap.hpp"
35#include "runtime/thread.inline.hpp"
36
37bool JfrGetCallTrace::find_top_frame(frame& top_frame, Method** method, frame& first_frame) {
38 assert(top_frame.cb() != NULL, "invariant");
39 RegisterMap map(_thread, false);
40 frame candidate = top_frame;
41 for (u4 i = 0; i < MAX_STACK_DEPTH * 2; ++i) {
42 if (candidate.is_entry_frame()) {
43 JavaCallWrapper *jcw = candidate.entry_frame_call_wrapper_if_safe(_thread);
44 if (jcw == NULL || jcw->is_first_frame()) {
45 return false;
46 }
47 }
48
49 if (candidate.is_interpreted_frame()) {
50 JavaThreadState state = _thread->thread_state();
51 const bool known_valid = (state == _thread_in_native || state == _thread_in_vm || state == _thread_blocked);
52 if (known_valid || candidate.is_interpreted_frame_valid(_thread)) {
53 Method* im = candidate.interpreter_frame_method();
54 if (known_valid && !Method::is_valid_method(im)) {
55 return false;
56 }
57 *method = im;
58 first_frame = candidate;
59 return true;
60 }
61 }
62
63 if (candidate.cb()->is_nmethod()) {
64 // first check to make sure that we have a sane stack,
65 // the PC is actually inside the code part of the codeBlob,
66 // and we are past is_frame_complete_at (stack has been setup)
67 if (!candidate.safe_for_sender(_thread)) {
68 return false;
69 }
70 nmethod* nm = (nmethod*)candidate.cb();
71 *method = nm->method();
72
73 if (_in_java) {
74 PcDesc* pc_desc = nm->pc_desc_near(candidate.pc() + 1);
75 if (pc_desc == NULL || pc_desc->scope_decode_offset() == DebugInformationRecorder::serialized_null) {
76 return false;
77 }
78 candidate.set_pc(pc_desc->real_pc(nm));
79 assert(nm->pc_desc_at(candidate.pc()) != NULL, "invalid pc");
80 }
81 first_frame = candidate;
82 return true;
83 }
84
85 if (!candidate.safe_for_sender(_thread) ||
86 candidate.is_stub_frame() ||
87 candidate.cb()->frame_size() <= 0) {
88 return false;
89 }
90
91 candidate = candidate.sender(&map);
92 if (candidate.cb() == NULL) {
93 return false;
94 }
95 }
96 return false;
97}
98
99bool JfrGetCallTrace::get_topframe(void* ucontext, frame& topframe) {
100 if (!_thread->pd_get_top_frame_for_profiling(&topframe, ucontext, _in_java)) {
101 return false;
102 }
103
104 if (topframe.cb() == NULL) {
105 return false;
106 }
107
108 frame first_java_frame;
109 Method* method = NULL;
110 if (find_top_frame(topframe, &method, first_java_frame)) {
111 if (method == NULL) {
112 return false;
113 }
114 topframe = first_java_frame;
115 return true;
116 }
117 return false;
118}
119