Java example source code file (method_invocation_tree.d)

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Java - Java tags/keywords

begin, end, method_entry_cnt, method_return_cnt, sample_name

The method_invocation_tree.d Java example source code

#!/usr/sbin/dtrace -Zs
/*
 * Copyright (c) 2006, Oracle and/or its affiliates. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *   - Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *
 *   - Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution.
 *
 *   - Neither the name of Oracle nor the names of its
 *     contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
 * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/*
*/

/*
 * Usage:
 *   1. method_invocation_tree.d -c "java ..."
 *   2. method_invocation_tree.d -p JAVA_PID
 *
 * This script prints tree of Java and JNI method invocations.
 *
 * Notes:
 *  - These probes are disabled by default since it incurs performance
 *    overhead to the application. To trace the method-entry and
 *    method-exit probes, you need to turn on the ExtendedDTraceProbes VM
 *    option.  
 *    You can either start the application with -XX:+ExtendedDTraceProbes
 *    option or use the jinfo command to enable it at runtime as follows:
 *
 *       jinfo -flag +ExtendedDTraceProbes <java_pid>
 *
 */

#pragma D option quiet
#pragma D option destructive
#pragma D option defaultargs
#pragma D option bufsize=16m
#pragma D option aggrate=100ms

self char *str_ptr;
self string class_name;
self string method_name;
self string signature;

self int indent;

BEGIN
{
    SAMPLE_NAME = "hotspot method invocation tracing";

    printf("BEGIN %s\n\n", SAMPLE_NAME);
}

hotspot$target:::*
/!self->indent/
{
    self->indent = 0;
}

/*
 * hotspot:::method-entry, hotspot:::method-return probe arguments:
 *  arg0: uintptr_t,    Java thread id
 *  arg1: char*,        a pointer to mUTF-8 string containing the name of
 *                          the class of the method being entered
 *  arg2: uintptr_t,    the length of the class name (in bytes)
 *  arg3: char*,        a pointer to mUTF-8 string data which contains the
 *                          name of the method being entered
 *  arg4: uintptr_t,    the length of the method name (in bytes)
 *  arg5: char*,        a pointer to mUTF-8 string data which contains the
 *                          signature of the method being entered
 *  arg6: uintptr_t,    the length of the signature(in bytes)
 */

hotspot$target:::method-return
{
    self->indent --;
    METHOD_RETURN_CNT ++
}

hotspot$target:::method-entry
{
    self->indent ++;
    METHOD_ENTRY_CNT ++;

    self->str_ptr = (char*) copyin(arg1, arg2+1);
    self->str_ptr[arg2] = '\0';
    self->class_name = (string) self->str_ptr;

    self->str_ptr = (char*) copyin(arg3, arg4+1);
    self->str_ptr[arg4] = '\0';
    self->method_name = (string) self->str_ptr;

    self->str_ptr = (char*) copyin(arg5, arg6+1);
    self->str_ptr[arg6] = '\0';
    self->signature = (string) self->str_ptr;

    printf("%-10u%*s%s:%s:%s\n",
        tid, self->indent, "", self->class_name,
        self->method_name, self->signature);

}

hotspot_jni$target:::*_entry
{
    printf("%-10u%*sJNI:%s\n", tid, self->indent+1, "", probename);
}

:::END
{
    printf("METHOD_ENTRY_CNT:  %10d\n", METHOD_ENTRY_CNT);
    printf("METHOD_RETURN_CNT: %10d\n", METHOD_RETURN_CNT);

    printf("\nEND of %s\n", SAMPLE_NAME);
}

syscall::rexit:entry,
syscall::exit:entry
/pid == $target/
{
   exit(0);
}