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Subject: Re: [PATCH] blk: optimization for classic polling
To:     Keith Busch <keith.busch@intel.com>,
        Nitesh Shetty <nj.shetty@samsung.com>
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From:   Sagi Grimberg <sagi@grimberg.me>
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Date:   Thu, 8 Feb 2018 18:03:33 +0200
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> I think it'd be simpler to have blk_poll set it back to running if
> need_resched is true rather than repeat this patter across all the
> callers:
> 
> ---
> diff --git a/block/blk-mq.c b/block/blk-mq.c
> index df93102e2149..40285fe1c8ad 100644
> --- a/block/blk-mq.c
> +++ b/block/blk-mq.c
> @@ -3164,6 +3164,7 @@ static bool __blk_mq_poll(struct blk_mq_hw_ctx *hctx, struct request *rq)
>   		cpu_relax();
>   	}
>   
> +	set_current_state(TASK_RUNNING);
>   	return false;
>   }
>   
> --

Nice!