1 /*
 2  * Copyright (c) 2003, 2019, Oracle and/or its affiliates. All rights reserved.
 3  * Copyright (c) 2020, 2021, Huawei Technologies Co., Ltd. All rights reserved.
 4  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 5  *
 6  * This code is free software; you can redistribute it and/or modify it
 7  * under the terms of the GNU General Public License version 2 only, as
 8  * published by the Free Software Foundation.
 9  *
10  * This code is distributed in the hope that it will be useful, but WITHOUT
11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
13  * version 2 for more details (a copy is included in the LICENSE file that
14  * accompanied this code).
15  *
16  * You should have received a copy of the GNU General Public License version
17  * 2 along with this work; if not, write to the Free Software Foundation,
18  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
19  *
20  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
21  * or visit www.oracle.com if you need additional information or have any
22  * questions.
23  *
24  */
25 
26 #include "precompiled.hpp"
27 #include "runtime/frame.inline.hpp"
28 #include "runtime/thread.inline.hpp"
29 
30 frame JavaThread::pd_last_frame() {
31   assert(has_last_Java_frame(), "must have last_Java_sp() when suspended");
32   return frame(_anchor.last_Java_sp(), _anchor.last_Java_fp(), _anchor.last_Java_pc());
33 }
34 
35 // For Forte Analyzer AsyncGetCallTrace profiling support - thread is
36 // currently interrupted by SIGPROF
37 bool JavaThread::pd_get_top_frame_for_signal_handler(frame* fr_addr,
38   void* ucontext, bool isInJava) {
39 
40   assert(Thread::current() == this, "caller must be current thread");
41   return pd_get_top_frame(fr_addr, ucontext, isInJava);
42 }
43 
44 bool JavaThread::pd_get_top_frame_for_profiling(frame* fr_addr, void* ucontext, bool isInJava) {
45   return pd_get_top_frame(fr_addr, ucontext, isInJava);
46 }
47 
48 bool JavaThread::pd_get_top_frame(frame* fr_addr, void* ucontext, bool isInJava) {
49   // If we have a last_Java_frame, then we should use it even if
50   // isInJava == true.  It should be more reliable than ucontext info.
51   if (has_last_Java_frame() && frame_anchor()->walkable()) {
52     *fr_addr = pd_last_frame();
53     return true;
54   }
55 
56   // At this point, we don't have a last_Java_frame, so
57   // we try to glean some information out of the ucontext
58   // if we were running Java code when SIGPROF came in.
59   if (isInJava) {
60     ucontext_t* uc = (ucontext_t*) ucontext;
61 
62     intptr_t* ret_fp = NULL;
63     intptr_t* ret_sp = NULL;
64     address addr = os::fetch_frame_from_context(uc, &ret_sp, &ret_fp);
65     if (addr == NULL || ret_sp == NULL ) {
66       // ucontext wasn't useful
67       return false;
68     }
69 
70     frame ret_frame(ret_sp, ret_fp, addr);
71     if (!ret_frame.safe_for_sender(this)) {
72 #ifdef COMPILER2
73       frame ret_frame2(ret_sp, NULL, addr);
74       if (!ret_frame2.safe_for_sender(this)) {
75         // nothing else to try if the frame isn't good
76         return false;
77       }
78       ret_frame = ret_frame2;
79 #else
80       // nothing else to try if the frame isn't good
81       return false;
82 #endif /* COMPILER2 */
83     }
84     *fr_addr = ret_frame;
85     return true;
86   }
87 
88   // nothing else to try
89   return false;
90 }
91 
92 void JavaThread::cache_global_variables() { }