On 9/21/05, raja <vnagaraju@xxxxxxxxxxxx> wrote:
> Hi,
> I am trying to trace the race condition by creating 2 threads in
> kernel space. One thread incriments a global value and other
> decrements that value.
> But I am unable to trace the race condition.
> I am listing my code.Will you please help me.
>
>
> static int __init init_module_atomic(void);
> static void __exit exit_module_atomic(void);
>
No need for the above declaration ..........
> int value=0;
Can change this to unsigned long value .........
>
> int thread_function_1(void * data)
> {
> printk("Entered into Thread 1\n");
> int i;
> for(i=0;i<1000;i++)
> {
Can change this loop to for( ; ; ) to get the result more properly
> udelay(1000);
Change this to schedule();
> value++;
> printk("Value Is : %d\t",value);
> }
> printk("Exited From Thread 1\n");
> return 0;
> }
>
> int thread_function_2(void * data)
> {
> printk("Entered into Thread 2\n");
> int i;
> for(i=0;i<1000;i++)
> {
Change to for ( ; ; )
> udelay(100);
change to schedule()
> value--;
> printk("Value Is : %d\t",value);
> }
> printk("Exited From Thread 2\n");
> return 0;
> }
>
In your code you won't be able to see just as your thread_1 terminates
quickly before starting thread_2 and udelay is stalling the whole CPU
and won't allow CPU to do other stuffs, so changing it to schedule()
will give you better result ...........
--
Fawad Lateef
--
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