Re: Proposal: HAVE_SEPARATE_IRQ_STACK?

From: Jason A. Donenfeld
Date: Thu Nov 10 2016 - 12:40:08 EST


Hi Thomas,

On Thu, Nov 10, 2016 at 2:00 PM, Thomas Gleixner <tglx@xxxxxxxxxxxxx> wrote:
> Do not even think about going there. That's going to be a major
> mess.

Lol! Okay. Thank you for reigning in my clearly reckless
propensities... Sometimes playing in traffic is awfully tempting.

>
> As a short time workaround you can increase THREAD_SIZE_ORDER for now and
> then fix it proper with switching to seperate irq stacks.

Okay. I think in the end I'll kmalloc, accept the 16% slowdown [1],
and focus efforts on having a separate IRQ stack. Matt emailed in this
thread saying he was already looking into it, so I think by the time
that slowdown makes a difference, we'll have the right pieces in place
anyway.

Thanks for the guidance here.

Regards,
Jason

[1] https://git.zx2c4.com/WireGuard/commit/?id=cc3d7df096a88cdf96d016bdcb2f78fa03abb6f3