#!/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. CriticalSection.d -c "java ..."

 *    2. CriticalSection.d -p JAVA_PID

 *

 * The script inspect a JNI application for Critical Section violations.

 *

 * Critical section is the space between calls to JNI methods:

 *   - GetPrimitiveArrayCritical and ReleasePrimitiveArrayCritical; or

 *   - GetStringCritical and ReleaseStringCritical.

 *

 * Inside a critical section, native code must not call other JNI functions,

 * or any system call that may cause the current thread to block and wait

 * for another Java thread. (For example, the current thread must not call

 * read on a stream being written by another Java thread.)

 *

 */

#pragma D option quiet

#pragma D option destructive

#pragma D option defaultargs

#pragma D option bufsize=16m

#pragma D option aggrate=100ms

self int in_critical_section;

self string critical_section_name;

int CRITICAL_SECTION_VIOLATION_CNT;

:::BEGIN

{

    SAMPLE_NAME = "critical section violation checks";

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

}

/*

 *   Multiple pairs of GetPrimitiveArrayCritical/ReleasePrimitiveArrayCritical,

 *   GetStringCritical/ReleaseStringCritical may be nested

 */

hotspot_jni$target:::*_entry

/self->in_critical_section > 0 &&

  probename != "GetPrimitiveArrayCritical_entry" &&

  probename != "GetStringCritical_entry" &&

  probename != "ReleasePrimitiveArrayCritical_entry" &&

  probename != "ReleaseStringCritical_entry" &&

  probename != "GetPrimitiveArrayCritical_return" &&

  probename != "GetStringCritical_return" &&

  probename != "ReleasePrimitiveArrayCritical_return" &&

  probename != "ReleaseStringCritical_return"/

{

    printf("\nJNI call %s made from JNI critical region '%s'\n",

        probename, self->critical_section_name);

    printf("Jstack:\n");

    jstack(50, 500);

    CRITICAL_SECTION_VIOLATION_CNT ++;

}

syscall:::entry

/pid == $target && self->in_critical_section > 0/

{

    printf("\nSystem call %s made in JNI critical region '%s'\n",

        probefunc, self->critical_section_name);

    printf("Jstack:\n");

    jstack(50, 500);

    CRITICAL_SECTION_VIOLATION_CNT ++;

}

hotspot_jni$target:::ReleasePrimitiveArrayCritical_entry,

hotspot_jni$target:::ReleaseStringCritical_entry

/self->in_critical_section > 0/

{

    self->in_critical_section --;

}

hotspot_jni$target:::GetPrimitiveArrayCritical_return

{

    self->in_critical_section ++;

    self->critical_section_name = "GetPrimitiveArrayCritical";

}

hotspot_jni$target:::GetStringCritical_return

{

    self->in_critical_section ++;

    self->critical_section_name = "GetStringCritical";

}

:::END

{

    printf("%d critical section violations have been discovered\n",

        CRITICAL_SECTION_VIOLATION_CNT);

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

}