/*
* Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*
*/
#include "precompiled.hpp"
#include "runtime/frame.inline.hpp"
#include "thread_linux.inline.hpp"
// For Forte Analyzer AsyncGetCallTrace profiling support - thread is
// currently interrupted by SIGPROF
bool JavaThread::pd_get_top_frame_for_signal_handler(frame* fr_addr,
void* ucontext,
bool isInJava) {
assert(Thread::current() == this, "caller must be current thread");
assert(this->is_Java_thread(), "must be JavaThread");
JavaThread* jt = (JavaThread *)this;
if (!isInJava) {
// make_walkable flushes register windows and grabs last_Java_pc
// which can not be done if the ucontext sp matches last_Java_sp
// stack walking utilities assume last_Java_pc set if marked flushed
jt->frame_anchor()->make_walkable(jt);
}
// If we have a walkable last_Java_frame, then we should use it
// even if isInJava == true. It should be more reliable than
// ucontext info.
if (jt->has_last_Java_frame() && jt->frame_anchor()->walkable()) {
*fr_addr = jt->pd_last_frame();
return true;
}
ucontext_t* uc = (ucontext_t*) ucontext;
// At this point, we don't have a walkable last_Java_frame, so
// we try to glean some information out of the ucontext.
intptr_t* ret_sp;
ExtendedPC addr =
os::fetch_frame_from_context(uc, &ret_sp,
NULL /* ret_fp only used on X86 */);
if (addr.pc() == NULL || ret_sp == NULL) {
// ucontext wasn't useful
return false;
}
// we were running Java code when SIGPROF came in
if (isInJava) {
// If we have a last_Java_sp, then the SIGPROF signal caught us
// right when we were transitioning from _thread_in_Java to a new
// JavaThreadState. We use last_Java_sp instead of the sp from
// the ucontext since it should be more reliable.
if (jt->has_last_Java_frame()) {
ret_sp = jt->last_Java_sp();
}
// Implied else: we don't have a last_Java_sp so we use what we
// got from the ucontext.
frame ret_frame(ret_sp, frame::unpatchable, addr.pc());
if (!ret_frame.safe_for_sender(jt)) {
// nothing else to try if the frame isn't good
return false;
}
*fr_addr = ret_frame;
return true;
}
// At this point, we know we weren't running Java code. We might
// have a last_Java_sp, but we don't have a walkable frame.
// However, we might still be able to construct something useful
// if the thread was running native code.
if (jt->has_last_Java_frame()) {
assert(!jt->frame_anchor()->walkable(), "case covered above");
if (jt->thread_state() == _thread_in_native) {
frame ret_frame(jt->last_Java_sp(), frame::unpatchable, addr.pc());
if (!ret_frame.safe_for_sender(jt)) {
// nothing else to try if the frame isn't good
return false;
}
*fr_addr = ret_frame;
return true;
}
}
// nothing else to try
return false;
}
void JavaThread::cache_global_variables() { }