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Subject: Re: Re [PATCH] Adding multiple workers to the loop device.
To:     "muraliraja.muniraju" <muraliraja.muniraju@rubrik.com>
Cc:     Chaitanya.Kulkarni@wdc.com, Jens Axboe <axboe@kernel.dk>,
        linux-block@vger.kernel.org, linux-kernel@vger.kernel.org
References: <DM6PR04MB5754D8E261B4200AA62D442D860D0@DM6PR04MB5754.namprd04.prod.outlook.com>
 <20200121201014.52345-1-muraliraja.muniraju@rubrik.com>
From:   Bart Van Assche <bvanassche@acm.org>
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Date:   Tue, 21 Jan 2020 20:01:44 -0800
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On 2020-01-21 12:10, muraliraja.muniraju wrote:
> +	for (i = 0; i < lo->num_loop_workers; i++) {
> +		kthread_init_worker(&(lo->workers[i]));
> +		lo->worker_tasks[i] = kthread_run(
> +				loop_kthread_worker_fn, &(lo->workers[i]),
> +				"loop%d(%d)", lo->lo_number, i);
> +		if (IS_ERR((lo->worker_tasks[i])))
> +			goto err;
> +		set_user_nice(lo->worker_tasks[i], MIN_NICE);
> +	}

Unless if there is a really good reason, the workqueue mechanism should
be used instead of creating kthreads. And again unless if there is a
really good reason, one of the system workqueues (e.g. system_wq) should
be used instead of creating dedicated workqueues.

Bart.