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From:   ebiederm@xmission.com (Eric W. Biederman)
To:     Yu Zhao <yuzhao@google.com>
Cc:     Alexey Gladkov <legion@kernel.org>,
        Rune Kleveland <rune.kleveland@infomedia.dk>,
        Jordan Glover <Golden_Miller83@protonmail.ch>,
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Date:   Mon, 18 Oct 2021 10:35:12 -0500
In-Reply-To: <CAOUHufbbPMzMLaPH8o+PKG64RQaO7=09nv1hBnQY8SRAW+Jd-g@mail.gmail.com>
        (Yu Zhao's message of "Sun, 17 Oct 2021 13:35:37 -0600")
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Subject: Re: [CFT][PATCH] ucounts: Fix signal ucount refcounting
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Yu Zhao <yuzhao@google.com> writes:

> On Sat, Oct 16, 2021 at 11:35 AM Eric W. Biederman
> <ebiederm@xmission.com> wrote:
>>
>> Alexey Gladkov <legion@kernel.org> writes:
>>
>> > On Fri, Oct 15, 2021 at 05:10:58PM -0500, Eric W. Biederman wrote:
>> >> +                    goto dec_unwind;
>> >> +    }
>> >> +    return ret;
>> >> +dec_unwind:
>> >> +    dec = atomic_long_add_return(1, &iter->ucount[type]);
>> >
>> > Should be -1 ?
>>
>> Yes it should.  I will fix and resend.
>
> Or just atomic_long_dec_return().

It would have to be atomic_long_sub_return().

Even then I would want to change all of kernel/ucount.c to use
the same helper function so discrepancies can easily be spotted.

It is a good idea, just not I think for this particular patch.

Eric