Messages in this thread | | | Date | Fri, 09 Jan 2004 02:12:00 +1100 | From | Nick Piggin <> | Subject | Re: [patch] RCU for low latency [1/2] |
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Dipankar Sarma wrote:
>Provide a rq_has_rt_task() interface to detect runqueues with >real time priority tasks. Useful for RCU optimizations. >
Can you make rq_has_rt_task the slow path? Adding things like this can actually be noticable on microbenchmarks (eg. pipe based ctx switching). Its probably cache artifacts that I see, but it wouldn't hurt to keep the scheduler as tight as possible.
I think this should cover it.
int rq_has_rt_task(int cpu) { runqueue_t *rq = cpu_rq(cpu); return (sched_find_first_bit(rq->active) < MAX_RT_PRIO); }
Any good?
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