linux/tools
Jin Yao 493be70ac3 perf stat: Disable the NMI watchdog message on hybrid
If we run a single workload that only runs on big core, there is always
a ugly message about disabling the NMI watchdog because the atom is not
counted.

Before:

  # ./perf stat true

   Performance counter stats for 'true':

                0.43 msec task-clock                #    0.396 CPUs utilized
                   0      context-switches          #    0.000 /sec
                   0      cpu-migrations            #    0.000 /sec
                  45      page-faults               #  103.918 K/sec
             639,634      cpu_core/cycles/          #    1.477 G/sec
       <not counted>      cpu_atom/cycles/                                              (0.00%)
             643,498      cpu_core/instructions/    #    1.486 G/sec
       <not counted>      cpu_atom/instructions/                                        (0.00%)
             123,715      cpu_core/branches/        #  285.694 M/sec
       <not counted>      cpu_atom/branches/                                            (0.00%)
               4,094      cpu_core/branch-misses/   #    9.454 M/sec
       <not counted>      cpu_atom/branch-misses/                                       (0.00%)

         0.001092407 seconds time elapsed

         0.001144000 seconds user
         0.000000000 seconds sys

  Some events weren't counted. Try disabling the NMI watchdog:
          echo 0 > /proc/sys/kernel/nmi_watchdog
          perf stat ...
          echo 1 > /proc/sys/kernel/nmi_watchdog

  # ./perf stat -e '{cpu_atom/cycles/,msr/tsc/}' true

   Performance counter stats for 'true':

       <not counted>      cpu_atom/cycles/                                              (0.00%)
       <not counted>      msr/tsc/                                                      (0.00%)

         0.001904106 seconds time elapsed

         0.001947000 seconds user
         0.000000000 seconds sys

  Some events weren't counted. Try disabling the NMI watchdog:
          echo 0 > /proc/sys/kernel/nmi_watchdog
          perf stat ...
          echo 1 > /proc/sys/kernel/nmi_watchdog
  The events in group usually have to be from the same PMU. Try reorganizing the group.

Now we disable the NMI watchdog message on hybrid, otherwise there
are too many false positives.

After:

  # ./perf stat true

   Performance counter stats for 'true':

                0.79 msec task-clock                #    0.419 CPUs utilized
                   0      context-switches          #    0.000 /sec
                   0      cpu-migrations            #    0.000 /sec
                  48      page-faults               #   60.889 K/sec
             777,692      cpu_core/cycles/          #  986.519 M/sec
       <not counted>      cpu_atom/cycles/                                              (0.00%)
             669,147      cpu_core/instructions/    #  848.828 M/sec
       <not counted>      cpu_atom/instructions/                                        (0.00%)
             128,635      cpu_core/branches/        #  163.176 M/sec
       <not counted>      cpu_atom/branches/                                            (0.00%)
               4,089      cpu_core/branch-misses/   #    5.187 M/sec
       <not counted>      cpu_atom/branch-misses/                                       (0.00%)

         0.001880649 seconds time elapsed

         0.001935000 seconds user
         0.000000000 seconds sys

  # ./perf stat -e '{cpu_atom/cycles/,msr/tsc/}' true

   Performance counter stats for 'true':

       <not counted>      cpu_atom/cycles/                                              (0.00%)
       <not counted>      msr/tsc/                                                      (0.00%)

         0.000963319 seconds time elapsed

         0.000999000 seconds user
         0.000000000 seconds sys

Signed-off-by: Jin Yao <yao.jin@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
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/20210610034557.29766-1-yao.jin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2021-07-07 11:37:23 -03:00
..
accounting
arch tools headers UAPI: Synch KVM's svm.h header with the kernel 2021-07-01 16:14:37 -03:00
bootconfig bootconfig: Share the checksum function with tools 2021-06-10 13:41:26 -04:00
bpf Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2021-06-29 15:45:27 -07:00
build tools build: Fix quiet cmd indentation 2021-05-17 12:10:03 +09:00
cgroup tools/cgroup/slabinfo.py: updated to work on current kernel 2021-04-23 14:42:40 -07:00
debugging tools: Fix "the the" in a message in kernel-chktaint 2021-06-13 17:01:17 -06:00
edid
firewire
firmware
gpio tools: gpio-utils: fix various kernel-doc warnings 2021-03-26 14:56:19 +01:00
hv
iio iio: event_monitor: Enable events before monitoring 2021-03-25 19:13:52 +00:00
include tools headers UAPI: Sync files changed by the quotactl_fd new syscall 2021-07-05 14:36:22 -03:00
io_uring
kvm/kvm_stat tools/kvm_stat: Fix documentation typo 2021-05-07 06:06:22 -04:00
laptop
leds
lib perf tools changes for v5.14: 2021-07-02 12:24:31 -07:00
memory-model tools/memory-model: Fix smp_mb__after_spinlock() spelling 2021-05-10 16:27:20 -07:00
objtool A single ELF format fix for a section flags mismatch bug that breaks 2021-06-28 11:35:55 -07:00
pci
pcmcia
perf perf stat: Disable the NMI watchdog message on hybrid 2021-07-07 11:37:23 -03:00
power tools/power/x86/intel-speed-select: v1.10 release 2021-06-18 15:29:32 +02:00
rcu tools/rcu: Add drgn script to dump number of RCU callbacks 2021-05-10 15:39:19 -07:00
scripts tools build: Fix quiet cmd indentation 2021-05-17 12:10:03 +09:00
spi spi: tools: make a symbolic link to the header file spi.h 2021-04-22 16:30:39 +01:00
testing Merge branch 'core-rcu-2021.07.04' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu 2021-07-04 12:58:33 -07:00
thermal/tmon tools: do not include scripts/Kbuild.include 2021-04-25 05:26:13 +09:00
time
tracing
usb treewide: remove editor modelines and cruft 2021-05-07 00:26:34 -07:00
virtio
vm tools/vm/page_owner_sort.c: check malloc() return 2021-06-29 10:53:47 -07:00
wmi
Makefile