Subject: [PATCH 0/4] Efficiency cleanups

From: [email-masked] (Will Deacon)
Date: Mon, 24 Aug 2015 15:36:20 +0100

On Fri, Aug 21, 2015 at 02:46:30PM +0100, Russell King - ARM Linux wrote:
> While developing the previous patch set, I noticed that the kernel's
> "fast" exit path efficiency was not what it's supposed to be due to the
> addition of trace and context tracking.
> 
> These add several instances of register stacking and unstacking around
> various function calls, several of which we can avoid.  Many of these
> instances don't need to stack any register other than r0.
> 
> Moreover, we can avoid stacking and unstacking r0 if these features are
> enabled by storing r0 in the pt_regs as we would do in our slow return
> path.
> 
> Various other cleanups are included in this set as well.  Acks welcome.

All four patches look fine to me:

  Acked-by: Will Deacon <[email-masked]>

For some reason, I thought the numbering of the TIF_ flags was important
for some immediate construction in asm code, but either I'm mistaken or
it's no longer the case.

Will