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Date:   Mon, 21 Mar 2022 16:54:35 +0300
From:   Dan Carpenter <dan.carpenter@oracle.com>
To:     Jakob Koschel <jakobkoschel@gmail.com>
Cc:     Joseph Qi <joseph.qi@linux.alibaba.com>,
        Mark Fasheh <mark@fasheh.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        ocfs2-devel@oss.oracle.com, Joel Becker <jlbec@evilplan.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Geert Uytterhoeven <geert@linux-m68k.org>,
        Masahiro Yamada <masahiroy@kernel.org>,
        Miguel Ojeda <ojeda@kernel.org>,
        Mike Rapoport <rppt@kernel.org>,
        Brian Johannesmeyer <bjohannesmeyer@gmail.com>,
        Cristiano Giuffrida <c.giuffrida@vu.nl>,
        "Bos, H.J." <h.j.bos@vu.nl>
Subject: Re: [PATCH] ocfs2: fix check if list iterator did find an element
Message-ID: <20220321135435.GL336@kadam>
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On Mon, Mar 21, 2022 at 02:34:34PM +0100, Jakob Koschel wrote:
> >> @@ -556,11 +556,11 @@ static void *lockres_seq_start(struct seq_file *m, loff_t *pos)
> >> 		}
> >> 	}
> >> 
> >> -	list_for_each_entry(res, track_list, tracking) {
> >> -		if (&res->tracking == &dlm->tracking_list)
> >> -			res = NULL;
> >> -		else
> >> -			dlm_lockres_get(res);
> >> +	list_for_each_entry(iter, track_list, tracking) {
> >> +		if (&iter->tracking != &dlm->tracking_list) {

This is an open coded version of:

	if (!list_entry_is_head(iter, &dlm->tracking_list, tracking)) {

Ideally someone would come through with enough confidence to just delete
it but the second best option is to just make it readable...

regards,
dan carpenter

> >> +			dlm_lockres_get(iter);
> >> +			res = iter;
> >> +		}
> >> 		break;
> >> 	}