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Subject: Re: [Linaro-mm-sig] Re: [PATCH] epoll: try to be a _bit_ better about
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To: Linus Torvalds <torvalds@linux-foundation.org>,
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From: =?UTF-8?Q?Christian_K=C3=B6nig?= <ckoenig.leichtzumerken@gmail.com>
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Am 07.05.24 um 21:07 schrieb Linus Torvalds:
> On Tue, 7 May 2024 at 11:04, Daniel Vetter <daniel@ffwll.ch> wrote:
>> On Tue, May 07, 2024 at 09:46:31AM -0700, Linus Torvalds wrote:
>>
>>> I'd be perfectly ok with adding a generic "FISAME" VFS level ioctl
>>> too, if this is possibly a more common thing. and not just DRM wants
>>> it.
>>>
>>> Would something like that work for you?
>> Yes.
>>
>> Adding Simon and Pekka as two of the usual suspects for this kind of
>> stuff. Also example code (the int return value is just so that callers know
>> when kcmp isn't available, they all only care about equality):
>>
>> https://gitlab.freedesktop.org/mesa/mesa/-/blob/main/src/util/os_file.c#L239
> That example thing shows that we shouldn't make it a FISAME ioctl - we
> should make it a fcntl() instead, and it would just be a companion to
> F_DUPFD.
>
> Doesn't that strike everybody as a *much* cleaner interface? I think
> F_ISDUP would work very naturally indeed with F_DUPFD.
>
> Yes? No?

Sounds absolutely sane to me.

Christian.

>
>                         Linus