linux_dsm_epyc7002/tools
Jin Yao 72f02a947e perf stat: Fix wrong per-thread runtime stat for interval mode
root@kbl-ppc:~# perf stat --per-thread -e cycles,instructions -I1000 --interval-count 2
       1.004171683             perf-3696              8,747,311      cycles
          ...
       1.004171683             perf-3696                691,730      instructions              #    0.08  insn per cycle
          ...
       2.006490373             perf-3696              1,749,936      cycles
          ...
       2.006490373             perf-3696              1,484,582      instructions              #    0.28  insn per cycle
          ...

Let's see interval 2.006490373

  perf-3696              1,749,936      cycles
  perf-3696              1,484,582      instructions              #    0.28  insn per cycle

insn per cycle = 1,484,582 / 1,749,936 = 0.85.

But now it's 0.28, that's not correct.

stat_config.stats[] records the per-thread runtime stat. But for
interval mode, it should be reset for each interval.

So now, with this patch,

  root@kbl-ppc:~# perf stat --per-thread -e cycles,instructions -I1000 --interval-count 2
       1.005818121             perf-8633              9,898,045      cycles
          ...
       1.005818121             perf-8633                693,298      instructions              #    0.07  insn per cycle
          ...
       2.007863743             perf-8633              1,551,619      cycles
          ...
       2.007863743             perf-8633              1,317,514      instructions              #    0.85  insn per cycle
          ...

Let's check interval 2.007863743.

insn per cycle = 1,317,514 / 1,551,619 = 0.85. It's correct.

This patch creates runtime_stat_reset, places it next to
untime_stat_new/runtime_stat_delete and moves all runtime_stat
functions before process_interval.

Committer testing:

After the patch:

  # perf stat --per-thread -e cycles,instructions -I1000 --interval-count 2  |& grep sssd_nss-1130
     2.011309774  sssd_nss-1130   56,585  cycles
     2.011309774  sssd_nss-1130   13,121  instructions  # 0.23 insn per cycle
  # python
  >>> 13121.0 / 56585
  0.23188124061146947
  >>>

Fixes: commit 14e72a21c7 ("perf stat: Update or print per-thread stats")
Signed-off-by: Jin Yao <yao.jin@linux.intel.com>
Reviewed-by: Jiri Olsa <jolsa@redhat.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jin Yao <yao.jin@intel.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20200520042737.24160-2-yao.jin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-05-28 10:03:27 -03:00
..
accounting SPDX patches for 5.7-rc1. 2020-04-03 13:12:26 -07:00
arch tools arch x86: Sync asm/cpufeatures.h with the kernel sources 2020-04-14 09:08:23 -03:00
bootconfig tools/bootconfig: Fix apply_xbc() to return zero on success 2020-05-11 17:00:26 -04:00
bpf tools/runqslower: Ensure own vmlinux.h is picked up first 2020-04-24 17:45:20 -07:00
build perf: cs-etm: Update to build with latest opencsd version. 2020-05-05 16:35:32 -03:00
cgroup iocost: protect iocg->abs_vdebt with iocg->waitq.lock 2020-05-05 09:23:18 -06:00
debugging
edid
firewire
firmware
gpio This is the bulk of GPIO development for the v5.7 kernel cycle. 2020-04-04 10:27:00 -07:00
hv
iio
include Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-04-24 19:17:30 -07:00
io_uring
kvm/kvm_stat
laptop change email address for Pali Rohár 2020-04-10 15:36:22 -07:00
leds
lib Linux 5.7-rc7 2020-05-28 07:58:12 +02:00
memory-model
nfsd
objtool A set of fixes for x86: 2020-05-10 11:59:53 -07:00
pci tools: PCI: Add 'e' to clear IRQ 2020-04-02 17:57:10 +01:00
pcmcia
perf perf stat: Fix wrong per-thread runtime stat for interval mode 2020-05-28 10:03:27 -03:00
power pm-graph v5.6 2020-04-20 10:37:02 +02:00
scripts
spi SPDX patches for 5.7-rc1. 2020-04-03 13:12:26 -07:00
testing Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-05-23 17:16:18 -07:00
thermal/tmon - Convert tsens configuration DT binding to yaml (Rajeshwari) 2020-04-07 20:00:16 -07:00
time
usb
virtio tools/virtio: make asm/barrier.h self contained 2020-04-17 06:05:29 -04:00
vm tools/vm: fix cross-compile build 2020-04-21 11:11:56 -07:00
wmi
Makefile