From mboxrd@z Thu Jan  1 00:00:00 1970
From: Tejun Heo <tj@kernel.org>
Subject: Re: [PATCH v7 1/3] llist: Add a lock-less list variant terminated by
 a sentinel node
Date: Mon, 3 Oct 2022 07:36:50 -1000
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Sender: Tejun Heo <htejun@gmail.com>
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To: Waiman Long <longman@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>, cgroups@vger.kernel.org, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, Ming Lei <ming.lei@redhat.com>, Andy Shevchenko <andriy.shevchenko@linux.intel.com>, Andrew Morton <akpm@linux-foundation.org>, Michal =?iso-8859-1?Q?Koutn=FD?= <mkoutny@suse.com>

Hello,

On Mon, Oct 03, 2022 at 01:32:49PM -0400, Waiman Long wrote:
> What my current thinking is to make llist works with both NULL and sentinel
> terminated lockless list. Users who wish to use the sentinel terminated
> version will have to use special sentinel version of LLIST_HEAD() macro and
> llist_del_all() and __llist_del_all() functions. In this way, I don't need
> to touch an existing users of llist while minimizing code redundancy. What
> do you think?

Wouldn't that be more error-prone in the long term? I'd just bite the bullet
and convert the empty tests. It is a hassle to find them but given that it's
just the head node testing, it hopefully wouldn't be too bad.

Thanks.

-- 
tejun