Re: [v2 0/9] Early boot time stamps for x86

From: Pasha Tatashin
Date: Sat Mar 25 2017 - 09:57:27 EST


Hi Thomas,

The second versions was actually meant as a reply to your e-mail: the code differences were minimal: the main differences were in the cover letter. You mentioned that it is not necessary to have early boot time stamps, and I wanted to show examples how this data is useful to track scalability bugs and avoid future regressions.

Anyway, you asked for some time to think about this problem, I won't send any replies to this thread for the next two weeks. So, please consider this solution. The feature is well abstracted, does not harm the performance of the fast path, and if necessary it can also be made optional with something like:
CONFIG_HAVE_UNSTABLE_EARLY_CLOCK

Thank you,
Pasha

On 03/25/2017 06:25 AM, Thomas Gleixner wrote:
On Fri, 24 Mar 2017, Pavel Tatashin wrote:

changelog
---------
v1 - v2
In patch "x86/tsc: tsc early":
- added tsc_adjusted_early()
- fixed 32-bit compile error use do_div()

Did you actually read my last reply on V1 of this?

I made it entirely clear that the way this is done, i.e. hacking it into
the earliest boost stage is not going to happen.

Further I asked you to hold off until I found some time to look into this
in detail.

So what's the point of ignoring what I said and resending the whole lot
with some more hackery applied?

I don't care about you wasting your time, but I very much care about my
time.

Thanks,

tglx