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    Subject[patch] signal-latency-2.5.69-B0

    the attached patch, against BK-curr, further optimizes the 'kick wakeup'
    scheduler feature:

    - do not kick any CPU on UP

    - no need to mark the target task for reschedule - it's enough to send an
    interrupt to that CPU, that will initiate a signal processing pass.

    tested on x86 SMP and UP.

    Ingo

    --- linux/kernel/sched.c.orig
    +++ linux/kernel/sched.c
    @@ -500,9 +500,12 @@ repeat_lock_task:
    resched_task(rq->curr);
    }
    success = 1;
    - } else
    - if (unlikely(kick) && task_running(rq, p))
    - resched_task(rq->curr);
    + }
    +#if CONFIG_SMP
    + else
    + if (unlikely(kick) && task_running(rq, p) && (p->thread_info->cpu != smp_processor_id()))
    + smp_send_reschedule(p->thread_info->cpu);
    +#endif
    p->state = TASK_RUNNING;
    }
    task_rq_unlock(rq, &flags);
    -
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