From mboxrd@z Thu Jan  1 00:00:00 1970
From: corbet@lwn.net (Jonathan Corbet)
Subject: Re: [RFC/PATCH 2/8] revoke: inode revoke lock V7
Date: Tue, 18 Dec 2007 09:31:49 -0700
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To: Pekka J Enberg <penberg@cs.helsinki.fi>
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In-reply-to: Your message of "Fri, 14 Dec 2007 17:16:17 +0200."
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This is a relatively minor detail in the rather bigger context of this
patch, but...

> @@ -642,6 +644,7 @@ struct inode {
>  	struct list_head	inotify_watches; /* watches on this inode */
>  	struct mutex		inotify_mutex;	/* protects the watches list */
>  #endif
> +	wait_queue_head_t	i_revoke_wait;

That seems like a relatively hefty addition to every inode in the system
when revoke - I think - will be a fairly rare operation.  Would there be
any significant cost to using a single, global revoke-wait queue instead
of growing the inode structure?

jon