On Wed, Oct 21, 2020 at 2:34 PM Russell King - ARM Linux admin
[off-list ref] wrote:

We don't do it because we don't have a separate register to be able
to store the thread_info pointer, and copying that lump between the
SVC and IRQ stack will add massively to IRQ latency, especially for
older machines.

I forwarded my other reply as well, in which I suggested using
CONFIG_THREAD_INFO_IN_TASK, wouldn't that solve the problem?

      Arnd

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel