From mboxrd@z Thu Jan  1 00:00:00 1970
From: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Subject: Re: [RFC PATCH linux 2/2] fs/proc: use a hash table for the directory
 entries
Date: Fri, 03 Oct 2014 15:07:14 +0200
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Cc: netdev <netdev@vger.kernel.org>,
	Linux Kernel <linux-kernel@vger.kernel.org>,
	David Miller <davem@davemloft.net>,
	"Eric W. Biederman" <ebiederm@xmission.com>,
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	rui.xiang@huawei.com, Al Viro <viro@zeniv.linux.org.uk>,
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	Cyrill Gorcunov <gorcunov@openvz.org>,
	kirill.shutemov@linux.intel.com,
	Grant Likely <grant.likely@secretlab.ca>,
	Theodore Ts'o <tytso@mit.edu>,
	Thierry Herbelot <thierry.herbelot@6wind.com>
To: Alexey Dobriyan <adobriyan@gmail.com>
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Le 03/10/2014 12:55, Alexey Dobriyan a =C3=A9crit :
> On Thu, Oct 2, 2014 at 6:25 PM, Nicolas Dichtel
> <nicolas.dichtel@6wind.com> wrote:
>> --- a/fs/proc/generic.c
>> +++ b/fs/proc/generic.c
>> @@ -81,10 +81,13 @@ static int __xlate_proc_name(const char *name, s=
truct proc_dir_entry **ret,
>
>> +       if (!S_ISDIR(de->mode))
>> +               return -EINVAL;
>
> There are way too many S_ISDIR checks.
> In lookup and readdir, it is guaranteed that PDE is directory.
>
> I'd say all of them aren't needed because non-directories have
> ->subdir =3D NULL and
> directories have ->subdir !=3D NULL which transforms into hashtable o=
r
> rbtree or whatever,
> so you only need to guarantee only directories appear where they are
> expected and
> fearlessly use your new data structure traversing directories.
To be honest, they was put during the debug stage and I hesitated to re=
move
them at the end.
I will remove them!


Thank you,
Nicolas