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Kan Liang b95fcd2c1c perf vendor events intel: Add NO_NMI_WATCHDOG metric constraint
Add NO_NMI_WATCHDOG metric constraint to Page_Walks_Utilization for Sky Lake
and Cascade Lake.

Committer testing:

On a Lenovo T480S, Intel(R) Core(TM) i7-8650U Kaby Lake, that looking at x86's
mapfile.csv file is a:

  $ grep -w skylake tools/perf/pmu-events/arch/x86/mapfile.csv
  GenuineIntel-6-[4589]E,v24,skylake,core
  $

So uses the constraint added in this patch in this file:

  tools/perf/pmu-events/arch/x86/skylake/skl-metrics.json

Before:

  # perf stat -a -M Page_Walks_Utilization sleep 2

   Performance counter stats for 'system wide':

       <not counted>      itlb_misses.walk_pending                                      (0.00%)
       <not counted>      dtlb_load_misses.walk_pending                                     (0.00%)
       <not counted>      dtlb_store_misses.walk_pending                                     (0.00%)
       <not counted>      ept.walk_pending                                              (0.00%)
       <not counted>      cycles                                                        (0.00%)

         2.001750514 seconds time elapsed

  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.
  #

After:

  # perf stat -a -M Page_Walks_Utilization sleep 2
  Splitting metric group Page_Walks_Utilization into standalone metrics.
  Try disabling the NMI watchdog to comply NO_NMI_WATCHDOG metric constraint:
      echo 0 > /proc/sys/kernel/nmi_watchdog
      perf stat ...
      echo 1 > /proc/sys/kernel/nmi_watchdog
  ,
   Performance counter stats for 'system wide':

          36,883,102      itlb_misses.walk_pending  #      0.1 Page_Walks_Utilization   (79.99%)
         123,104,146      dtlb_load_misses.walk_pending                                     (80.02%)
          13,720,795      dtlb_store_misses.walk_pending                                     (79.99%)
                   0      ept.walk_pending                                              (79.99%)
       1,519,948,400      cycles                                                        (80.01%)

         2.002170780 seconds time elapsed

  #

Before and after, if we disable the nmi_watchdog we get:

  # echo 0 > /proc/sys/kernel/nmi_watchdog
  # perf stat -a -M Page_Walks_Utilization sleep 2

   Performance counter stats for 'system wide':

          33,721,658      itlb_misses.walk_pending  #      0.1 Page_Walks_Utilization
          84,070,996      dtlb_load_misses.walk_pending
           9,816,071      dtlb_store_misses.walk_pending
                   0      ept.walk_pending
         704,920,899      cycles

         2.002331670 seconds time elapsed

  #

  More information about the metric expressions:

  # perf stat -v -a -M Page_Walks_Utilization sleep 2
  Using CPUID GenuineIntel-6-8E-A
  metric expr ( itlb_misses.walk_pending + dtlb_load_misses.walk_pending + dtlb_store_misses.walk_pending + ept.walk_pending ) / ( 2 * cycles ) for Page_Walks_Utilization
  found event itlb_misses.walk_pending
  found event dtlb_load_misses.walk_pending
  found event dtlb_store_misses.walk_pending
  found event ept.walk_pending
  found event cycles
  adding {itlb_misses.walk_pending,dtlb_load_misses.walk_pending,dtlb_store_misses.walk_pending,ept.walk_pending,cycles}:W
   -> cpu/umask=0x10,(null)=0x186a3,event=0x85/
   -> cpu/umask=0x10,(null)=0x1e8483,event=0x8/
   -> cpu/umask=0x10,(null)=0x1e8483,event=0x49/
   -> cpu/umask=0x10,(null)=0x1e8483,event=0x4f/
  itlb_misses.walk_pending: 8085772 16010162799 16010162799
  dtlb_load_misses.walk_pending: 28134579 16010162799 16010162799
  dtlb_store_misses.walk_pending: 7276535 16010162799 16010162799
  ept.walk_pending: 2 16010162799 16010162799
  cycles: 315140605 16010162799 16010162799

   Performance counter stats for 'system wide':

           8,085,772      itlb_misses.walk_pending  #      0.1 Page_Walks_Utilization
          28,134,579      dtlb_load_misses.walk_pending
           7,276,535      dtlb_store_misses.walk_pending
                   2      ept.walk_pending
         315,140,605      cycles

         2.002333181 seconds time elapsed

  #

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Link: http://lore.kernel.org/lkml/1582581564-184429-6-git-send-email-kan.liang@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-03-10 14:56:46 -03:00
arch Merge remote-tracking branch 'acme/perf/urgent' into perf/core 2020-03-04 10:29:19 -03:00
block blk-mq: Remove some unused function arguments 2020-02-26 10:34:41 -07:00
certs certs: Add wrapper function to check blacklisted binary hash 2019-11-12 12:25:50 +11:00
crypto Merge branch 'next-integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity 2020-02-20 15:15:16 -08:00
Documentation ACPI fixes for 5.6-rc4 2020-02-28 09:02:18 -08:00
drivers Merge branch 'efi-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2020-03-02 06:41:41 -06:00
fs five small cifs/smb3 fixes, two for stable 2020-03-03 17:31:19 -06:00
include Merge remote-tracking branch 'acme/perf/urgent' into perf/core 2020-03-04 10:29:19 -03:00
init Tracing updates: 2020-02-26 10:34:42 -08:00
ipc Revert "ipc,sem: remove uneeded sem_undo_list lock usage in exit_sem()" 2020-02-21 11:22:15 -08:00
kernel Merge remote-tracking branch 'acme/perf/urgent' into perf/core 2020-03-04 10:29:19 -03:00
lib Tracing updates: 2020-02-26 10:34:42 -08:00
LICENSES LICENSES: Rename other to deprecated 2019-05-03 06:34:32 -06:00
mm Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2020-02-24 11:32:15 -08:00
net vsock: fix potential deadlock in transport->release() 2020-02-27 12:03:56 -08:00
samples Kbuild updates for v5.6 (2nd) 2020-02-09 16:05:50 -08:00
scripts kbuild: remove unneeded semicolon at the end of cmd_dtb_check 2020-02-27 02:24:34 +09:00
security Merge branch 'next-integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity 2020-02-20 15:15:16 -08:00
sound ASoC: Fixes for v5.6 2020-02-18 13:33:39 +01:00
tools perf vendor events intel: Add NO_NMI_WATCHDOG metric constraint 2020-03-10 14:56:46 -03:00
usr Kbuild updates for v5.6 (2nd) 2020-02-09 16:05:50 -08:00
virt KVM/arm fixes for 5.6, take #1 2020-02-28 11:50:06 +01:00
.clang-format clang-format: Update with the latest for_each macro list 2019-08-31 10:00:51 +02:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore Opt out of scripts/get_maintainer.pl 2019-05-16 10:53:40 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
.gitignore selftest/lkdtm: Don't pollute 'git status' 2020-02-20 08:55:06 -07:00
.mailmap A handful of small documentation fixes that wandered in. 2020-02-07 13:03:10 -08:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: Hand MIPS over to Thomas 2020-02-24 22:43:18 -08:00
Kbuild kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
Kconfig docs: kbuild: convert docs to ReST and rename to *.rst 2019-06-14 14:21:21 -06:00
MAINTAINERS pci-v5.6-fixes-2 2020-02-28 11:51:53 -08:00
Makefile Linux 5.6-rc4 2020-03-01 16:38:46 -06:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.