Re: [PATCH net-next v2] net: skb: prevent the split of kfree_skb_reason() by gcc

From: Menglong Dong
Date: Mon Aug 15 2022 - 02:21:25 EST


Hello,

On Fri, Aug 12, 2022 at 4:50 PM Miguel Ojeda
<miguel.ojeda.sandonis@xxxxxxxxx> wrote:
>
> On Fri, Aug 12, 2022 at 4:50 AM <menglong8.dong@xxxxxxxxx> wrote:
> >
> > #define __noreturn __attribute__((__noreturn__))
> >
> > +#define __nofnsplit __attribute__((__optimize__("O1")))
>
> This is still in the wrong place...
>
> Also, from what the bot says, Clang does not support it. I took a
> look, and that seems to be the case. ICC doesn't, either. Thus you
> would need to guard it and also add the docs as needed, like the other
> attributes.
>
> (Not saying that solving the issue with the attribute is a good idea,
> but if you really wanted to add one, it should be done properly)
>

I have dug it deeper, and found that this function-split optimization
is only used by GCC. Therefore, I think I need only to consider it
for GCC.

I'll send a V3, thanks~

Menglong Dong

> Cheers,
> Miguel