From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andrew Morton <akpm@osdl.org>
Subject: Re: [PATCH 7/7] FS-Cache: CacheFiles: A cache that backs onto a
 mounted filesystem
Date: Thu, 20 Apr 2006 17:57:48 -0700
Message-ID: <20060420175748.64f592c0.akpm@osdl.org>
References: <20060420165927.9968.33912.stgit@warthog.cambridge.redhat.com>
	<20060420165941.9968.13602.stgit@warthog.cambridge.redhat.com>
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To: David Howells <dhowells@redhat.com>
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David Howells <dhowells@redhat.com> wrote:
>
> +		/* let keventd have some air occasionally */
>  +		max--;
>  +		if (max < 0 || need_resched()) {
>  +			if (!list_empty(&object->read_list))
>  +				schedule_work(&object->read_work);
>  +			_leave(" [maxed out]");
>  +			return;
>  +		}

That's perhaps not a terribly effective way of multiplexing keventd cycles.
If someone has done a schedule_work(), that will stick an entry onto
keventd's worklist, but it won't necessarily set need_resched().

We'd need to extend the workqueue API to be able to determine whether
there's other work pending.