lkml.org 
[lkml]   [2015]   [May]   [25]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Subject[PATCH 0/2] turbostat, support CPU0 hotplug [v2]
Date
turbostat does not function properly on systems that support CPU0 hotplug.
When running turbostat on these systems the following error is seen.

[root@intel-chiefriver-04 ~]# turbostat ls
turbostat: no /dev/cpu/0/msr
Try "# modprobe msr": No such file or directory

This happens because base_cpu is set to 0 in the turbostat code and calls
to check_dev_msr() will fail if CPU0 has been removed.

This patchset adds functionality to set the default cpu value to the
current running cpu. This patch moves setup_all_buffers() to the
beginning of the turbostat_init() so that set_base_cpu() can take advantage
of topo.max_cpu_num which is set in setup_all_buffers().

After this change, on a system that has CPU0 removed,

[root@prarit ~]# ./turbostat -d -d ls
turbostat version 4.5 2 Apr, 2015 - Len Brown <lenb@kernel.org>
num_cpus 7 max_cpu_num 7
cpu0 NOT PRESENT
cpu 1 pkg 0 core 0
cpu 2 pkg 0 core 1
cpu 3 pkg 0 core 1
cpu 4 pkg 0 core 2
cpu 5 pkg 0 core 2
cpu 6 pkg 0 core 3
cpu 7 pkg 0 core 3
<snip>
anaconda-ks.cfg README turbostat
Core CPU Avg_MHz %Busy Bzy_MHz TSC_MHz SMI CPU%c1 CPU%c3 CPU%c6 CPU%c7 CoreTmp PkgTmp Pkg%pc2 Pkg%pc3 Pkg%pc6 Pkg%pc7 PkgWatt CorWatt GFXWatt
- - 492 14.20 3462 2634 0 18.90 0.00 0.00 68.63 27 27 0.00 0.00 0.00 0.00 17.65 12.69 0.00
0 1 353 9.95 3552 2645 0 9.68 0.00 0.00 80.37 27 27 0.00 0.00 0.00 0.00 17.65 12.69 0.00
1 2 217 7.70 2814 2614 0 64.63 0.00 0.00 27.68 26
1 3 2006 57.20 3507 2660 0 15.61
2 4 120 3.37 3570 2649 0 10.95 0.00 0.00 85.69 25
2 5 155 4.22 3679 2631 0 9.48
3 6 296 8.38 3530 2620 0 11.07 0.00 0.00 80.55 17
3 7 296 8.15 3630 2617 0 11.22
0.001160 sec

I have additionally tested various other hotplug configurations to make sure
that turbostat behaves correctly in those situations as well.

[v2]: use sched_getcpu() to get current cpu

Signed-off-by: Prarit Bhargava <prarit@redhat.com>

Prarit Bhargava (2):
turbostat, add base_cpu
turbostat, add set_base_cpu()

tools/power/x86/turbostat/turbostat.c | 44 ++++++++++++++++++++++-----------
1 file changed, 30 insertions(+), 14 deletions(-)

--
1.7.9.3



\
 
 \ /
  Last update: 2015-05-25 15:01    [W:0.470 / U:0.008 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site