Re: [PATCH v3] staging: r8188eu: Use kzalloc() with GFP_ATOMIC in atomic context

Fabio M. De Francesco
2021-11-05T16:05:29Z

On Friday, November 5, 2021 4:36:33 PM CET Dan Carpenter wrote:
> Oh yeah, you're right. It never *just* does spinlocks (as stated in the
> commit message btw), it does spin_lock_bh() which bumps the soft IRQ
> count.

Thank you very much for checking and confirming.

> > To summarize, I think that using in_interrupt() in the old wrappers was
the
> > wiser choice.
>
> "Wiser" is not the right word. The wrappers were always stupid, but I
> guess they did work in this case so the fixes tag is correct.

Ah, sorry. I was not able to express my thought properly :(

I agree with you that the wrappers were a not a good idea and Larry did well
in removing them. Furthermore, I think that delegating the choice to use
GFP_KERNEL vs. GFP_ATOMIC depending on the return from in_interrupt() is very
bad design and it adds sensible overhead.

I used "wiser" is a stricter sense. I meant that, if wrappers were needed
(but they were not), in_interrupt() is "wiser" than "in_atomic()".

Regards,

Fabio M. De Francesco