Re: Is there a current known getrusage() problem (amd64)

[christos%astron.com@localhost (Christos Zoulas)]

In article <9363.1522926514%jinx.noi.kre.to@localhost>,
Robert Elz  <kre%munnari.OZ.AU@localhost> wrote:
>    Date:        Wed, 4 Apr 2018 17:05:51 -0400 (EDT)
>    From:        Mouse <mouse%Rodents-Montreal.ORG@localhost>
>    Message-ID:  <201804042105.RAA04131%Stone.Rodents-Montreal.ORG@localhost>
>
>  | >> Hmm...have you tried [various suggestions]?
>  | > No, to all of those - and all good suggestions (and since this is a
>  | > XEN DomU I can give it just 1 CPU as well...)
>  |
>  | Might also be interesting to see whether/how the symptoms change on
>  | real hardware, if you have any such available; with xen in the mix
>  | there are a bunch more possible places bugs could be causing trouble.
>
>I suspect they probably will, and yes, I could test this there (been meaning
>to update my laptop kernel anyway...)   but I am now not sure I will need to
>do that, as some progress has been made (almost by fluke).
>
>  | see that name: what, you're trying to configure Chris Demetriou?)
>:-)
>
>
>What I saw that "revealed all" is from sysctl ...
>
>kern.cp_time: user = 0, nice = 0, sys = 6764, intr = 107, idle = 4968970
>
>The test system has been up, idling, for about 14 hours, so that idle
>time is right.   The intr time (about 1 second) seems reasonable.
>
>But all the time being counted as system time, and none user time, is
>what I was seeing from the time command as well.
>
>What this means to me is that the test in kern_clock.c
>
>        if (CLKF_USERMODE(frame)) {
>
>is failing, and most likely just on XEN, as we know that the user/kernel
>distinction is done differently there than is on real hardware.
>
>On amd64, CLKF_USERMODE is just
>
>#define     CLKF_USERMODE(frame)    USERMODE((frame)->cf_if.if_tf.tf_cs)

Does it change anything to define it:

>#define     CLKF_USERMODE(frame)    (!KERNELMODE((frame)->cf_if.if_tf.tf_cs))

like sh3 does?

christos