Re: [PATCH 06/25] hrtimer: Store running timer in hrtimer_clock_base

[Thomas Gleixner]

On Mon, 25 Sep 2017, Peter Zijlstra wrote:

> On Thu, Aug 31, 2017 at 12:23:36PM -0000, Anna-Maria Gleixner wrote:
> > Unfortunately this makes cpu_clock base larger than 32 bytes on 32bit
> > kernels. Instead of having huge gaps due to alignment, remove the alignment
> > and let the compiler pack cpu base for 32bit. The resulting cache access
> > patterns are fortunately not really different from the current
> > behaviour.
> 
> How did you determine this? Perf lacks much useful tooling right about
> there :/

Just by analyzing the resulting layout and looking at the number of cache
lines involved for the frequently used clocks (mono/real).

Thanks,

	tglx