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Date:   Wed, 30 May 2018 09:11:59 -0400
From:   Johannes Weiner <hannes@cmpxchg.org>
To:     Josef Bacik <josef@toxicpanda.com>
Cc:     axboe@kernel.dk, kernel-team@fb.com, linux-block@vger.kernel.org,
        akpm@linux-foundation.org, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org, tj@kernel.org,
        linux-fsdevel@vger.kernel.org, Josef Bacik <jbacik@fb.com>
Subject: Re: [PATCH 06/13] blkcg: add generic throttling mechanism
Message-ID: <20180530131159.GB4035@cmpxchg.org>
References: <20180529211724.4531-1-josef@toxicpanda.com>
 <20180529211724.4531-7-josef@toxicpanda.com>
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On Tue, May 29, 2018 at 05:17:17PM -0400, Josef Bacik wrote:
> @@ -1099,6 +1099,11 @@ struct task_struct {
>  	unsigned int			memcg_nr_pages_over_high;
>  #endif
>  
> +#ifdef CONFIG_BLK_CGROUP
> +	struct request_queue		*throttle_queue;
> +	bool				use_memdelay;
> +#endif

Since you only touch use_memdelay from current, you can make this a
single bit and pack it with the other task flags farther up;
memcg_may_oom, no_cgroup_migration and friends.