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/*___INFO__MARK_BEGIN__*/
/*************************************************************************
*
* The Contents of this file are made available subject to the terms of
* the Sun Industry Standards Source License Version 1.2
*
* Sun Microsystems Inc., March, 2001
*
*
* Sun Industry Standards Source License Version 1.2
* =================================================
* The contents of this file are subject to the Sun Industry Standards
* Source License Version 1.2 (the "License"); You may not use this file
* except in compliance with the License. You may obtain a copy of the
* License at http://gridengine.sunsource.net/Gridengine_SISSL_license.html
*
* Software provided under this License is provided on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING,
* WITHOUT LIMITATION, WARRANTIES THAT THE SOFTWARE IS FREE OF DEFECTS,
* MERCHANTABLE, FIT FOR A PARTICULAR PURPOSE, OR NON-INFRINGING.
* See the License for the specific provisions governing your rights and
* obligations concerning the Software.
*
* The Initial Developer of the Original Code is: Sun Microsystems, Inc.
*
* Copyright: 2003 by Sun Microsystems, Inc.
*
* All Rights Reserved.
*
************************************************************************/
/*___INFO__MARK_END__*/
#include "test_sge_lock_main.h"
#include <unistd.h>
#include <stdio.h>
#include "uti/sge_lock.h"
#include "uti/sge_time.h"
static void *thread_function_1(void *anArg);
static void *thread_function_2(void *anArg);
int get_thrd_demand(void)
{
long p = 2; /* min num of threads */
#if defined(SOLARIS)
p = sysconf(_SC_NPROCESSORS_ONLN);
#endif
return (int)p;
}
void *(*get_thrd_func(void))(void *anArg)
{
static int i = 0;
return ((i++ % 2) ? thread_function_1 : thread_function_2) ;
}
void *get_thrd_func_arg(void)
{
return NULL;
}
void set_thread_count(int count)
{
return;
}
/****** test_sge_lock_simple/thread_function_1() *********************************
* NAME
* thread_function_1() -- Thread function to execute
*
* SYNOPSIS
* static void* thread_function_1(void *anArg)
*
* FUNCTION
* Acquire multiple locks and sleep. Release the locks. After each 'sge_lock()'
* and 'sge_unlock()' sleep to increase the probability of interlocked execution.
*
* Note: This function for itself is perfectly reasonable. However, a race
* condition, and thus a potential deadlock, does emerge if this function is
* run in parallel with 'thread_function_2()'.
*
* The reason for this is, that 'thread_function_1()' and 'thread_function_2()'
* each follow their own local acquire/release protocol. As a consequence,
* 'thread_function_1()' and 'thread_function_2()' acquire and release their
* respective locks in different orders.
*
* This example does reveal how important it is to obey a GLOBAL acquire/release
* protocol.
*
* INPUTS
* void *anArg - thread function arguments
*
* RESULT
* static void* - none
*
* SEE ALSO
* test_sge_deadlock/get_thrd_func()
* test_sge_deadlock/thread_function_2()
*******************************************************************************/
static void *thread_function_1(void *anArg)
{
DENTER(TOP_LAYER, "thread_function");
SGE_LOCK(LOCK_GLOBAL, LOCK_READ);
sleep(3);
SGE_LOCK(LOCK_MASTER_CONF, LOCK_READ);
sleep(3);
DPRINTF(("Thread %u sleeping at %d\n", (unsigned int) sge_locker_id(), (int) sge_get_gmt()));
sleep(5);
SGE_UNLOCK(LOCK_MASTER_CONF, LOCK_READ);
sleep(3);
SGE_UNLOCK(LOCK_GLOBAL, LOCK_READ);
sleep(3);
DEXIT;
return (void *)NULL;
} /* thread_function_1 */
/****** test_sge_deadlock/thread_function_2() **********************************
* NAME
* thread_function_2() -- Thread function to execute
*
* SYNOPSIS
* static void* thread_function_2(void *anArg)
*
* FUNCTION
* Acquire multiple locks and sleep. Release the locks. After each 'sge_lock()'
* and 'sge_unlock()' sleep to increase the probability of interlocked execution.
*
* Note: This function for itself is perfectly reasonable. However, a race
* condition, and thus a potential deadlock, does emerge if this function is
* run in parallel with 'thread_function_1()'.
*
* The reason for this is, that 'thread_function_2()' and 'thread_function_1()'
* each follow their own local acquire/release protocol. As a consequence,
* 'thread_function_2()' and 'thread_function_1()' acquire and release their
* respective locks in different orders.
*
* This example does reveal how important it is to obey a GLOBAL acquire/release
* protocol.
*
* INPUTS
* void *anArg - thread function arguments
*
* RESULT
* static void* - none
*
* SEE ALSO
* test_sge_deadlock/get_thrd_func()
* test_sge_deadlock/thread_function_1()
*******************************************************************************/
static void *thread_function_2(void *anArg)
{
DENTER(TOP_LAYER, "thread_function");
SGE_LOCK(LOCK_MASTER_CONF, LOCK_READ);
sleep(3);
SGE_LOCK(LOCK_GLOBAL, LOCK_READ);
sleep(3);
DPRINTF(("Thread %u sleeping\n", (unsigned int) sge_locker_id()));
sleep(5);
SGE_UNLOCK(LOCK_GLOBAL, LOCK_READ);
sleep(3);
SGE_UNLOCK(LOCK_MASTER_CONF, LOCK_READ);
sleep(3);
DEXIT;
return (void *)NULL;
} /* thread_function_2 */
int validate(int thread_count) {
return 0;
}
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