Re: [PATCH v1 1/2] perf auxtrace: Add 'T' itrace option for timestamp trace

From: Leo Yan
Date: Tue Nov 07 2023 - 09:18:22 EST


On Tue, Nov 07, 2023 at 12:16:25PM +0200, Adrian Hunter wrote:

[...]

> >>>> "If users know" <- how would users know? Could the kernel
> >>>> or tools also figure it out?
> >>>
> >>> Adrian, I'm trying to go all the outstanding patches, do you still have
> >>> any issues with this series?
> >>
> >> No, although the question wasn't actually answered. I presume users
> >> just have to try the 'T' option and see if it helps.
> >
> > Sometimes, users are software developers in SoC companies, they can
> > know well for the hardware design but are confused why current
> > implementation cannot use timestamp trace. This is the main reason
> > I sent this patch set.
> >
> > An example hardware platform is DB410c [1], we know its CoreSight can
> > support timestamp trace, but if without this adding option 'T', we
> > have no chance to use it due to it its CPU arch is prior to Armv8.4.
>
> perf config might be better than an itrace option, but you decide.

I understand perf config is a better approach due to users don't need
to bother inputting options after set it once. I will look at it and
respin new patch set.

Thanks for suggestion!

Leo