From mboxrd@z Thu Jan  1 00:00:00 1970
From: Christoph Hellwig <hch@infradead.org>
Subject: Re: [PATCH 1/4] target: Prevent cmd->se_queue_node double add
Date: Sat, 8 Oct 2011 21:24:14 -0400
Message-ID: <20111009012414.GA32104@infradead.org>
References: <1317358511-10664-1-git-send-email-nab@linux-iscsi.org>
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To: "Nicholas A. Bellinger" <nab@linux-iscsi.org>
Cc: target-devel <target-devel@vger.kernel.org>, linux-scsi <linux-scsi@vger.kernel.org>, Roland Dreier <roland@purestorage.com>, Andy Grover <agrover@redhat.com>

> +	/* If the cmd is already on the list, remove it before we add it */
> +	if (!list_empty(&cmd->se_queue_node))
> +		list_del(&cmd->se_queue_node);
> +	else
> +		atomic_inc(&qobj->queue_cnt);
> +

This is not an overly useful comment, as it states the obvious, aka what
we are doing here.  It is much better to explain why the semingly
unexpected (re-adding the same cmd) might be valid under certain
circumstances.  Even better would be asserts that we only do it under
those circumstances.