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Help required with a script


Hello,
This is the script which I had written to gather information on migration of
task to other CPU. I also wanted to report the appropriate errors, so I had
used 4 kernel.statement probes. But the problem is that all 4
kernel.statement probes get executed simultaneously, which should not happen
according to the original code. Please help in tracing the problem. Thanks.
Uname -r for the kernel is : 2.6.26.5-rt9


#! /usr/bin/env stap

probe kernel.function("__migrate_task")
{
        printf("\n__migrate_task called for process: \npid : %d\nSource CPU
: %d\tDestination CPU : %d",$p->pid,$src_cpu,$dest_cpu);
              printf("\nState: %d",task_state(task_current()))
              print_stack(backtrace())
}

/*
 *  6293:          if (unlikely(cpu_is_offline(dest_cpu)))
 *  6294:                 return ret; 
 */

probe kernel.statement("*@kernel/sched.c:6294")
{
                printf("\nError: Process failed to migrate. Destination CPU
(CPU %d) is offline.\n\n",$dest_cpu);
}

/*
 * 6307:    if (task_cpu(p) != src_cpu)
 * 6308:                goto done;
 */

probe kernel.statement("*@kernel/sched.c:6308")
{
                printf("\nTask already migrated to CPU %d\n\n",$dest_cpu);
}

/*
 * 6310:    if (!cpu_isset(dest_cpu, p->cpus_allowed))
 * 6311:               goto fail;
 */

probe kernel.statement("*@kernel/sched.c:6311")
{
                printf("\nError: Process failed to migrate to CPU %d. CPU
affinity of current task has changed.",$dest_cpu);
}

/*
 *  6317: set_task_cpu(p, dest_cpu);
 */

probe kernel.statement("*@kernel/sched.c:6317")
{
                printf("\nSuccess: Task successfully migrated\n\n");
}
-- 
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