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Zhengjun Xing 2652720096 perf stat: Fix L2 Topdown metrics disappear for raw events 
[ Upstream commit f0c86a2bae ]

In perf/Documentation/perf-stat.txt, for "--td-level" the default "0" means
the max level that the current hardware support.

So we need initialize the stat_config.topdown_level to TOPDOWN_MAX_LEVEL
when “--td-level=0” or no “--td-level” option. Otherwise, for the
hardware with a max level is 2, the 2nd level metrics disappear for raw
events in this case.

The issue cannot be observed for the perf stat default or "--topdown"
options. This commit fixes the raw events issue and removes the
duplicated code for the perf stat default.

Before:

 # ./perf stat -e "cpu-clock,context-switches,cpu-migrations,page-faults,instructions,cycles,ref-cycles,branches,branch-misses,{slots,topdown-retiring,topdown-bad-spec,topdown-fe-bound,topdown-be-bound,topdown-heavy-ops,topdown-br-mispredict,topdown-fetch-lat,topdown-mem-bound}" sleep 1

 Performance counter stats for 'sleep 1':

              1.03 msec cpu-clock                        #    0.001 CPUs utilized
                 1      context-switches                 #  966.216 /sec
                 0      cpu-migrations                   #    0.000 /sec
                60      page-faults                      #   57.973 K/sec
         1,132,112      instructions                     #    1.41  insn per cycle
           803,872      cycles                           #    0.777 GHz
         1,909,120      ref-cycles                       #    1.845 G/sec
           236,634      branches                         #  228.640 M/sec
             6,367      branch-misses                    #    2.69% of all branches
         4,823,232      slots                            #    4.660 G/sec
         1,210,536      topdown-retiring                 #     25.1% Retiring
           699,841      topdown-bad-spec                 #     14.5% Bad Speculation
         1,777,975      topdown-fe-bound                 #     36.9% Frontend Bound
         1,134,878      topdown-be-bound                 #     23.5% Backend Bound
           189,146      topdown-heavy-ops                #  182.756 M/sec
           662,012      topdown-br-mispredict            #  639.647 M/sec
         1,097,048      topdown-fetch-lat                #    1.060 G/sec
           416,121      topdown-mem-bound                #  402.063 M/sec

       1.002423690 seconds time elapsed

       0.002494000 seconds user
       0.000000000 seconds sys

After:

 # ./perf stat -e "cpu-clock,context-switches,cpu-migrations,page-faults,instructions,cycles,ref-cycles,branches,branch-misses,{slots,topdown-retiring,topdown-bad-spec,topdown-fe-bound,topdown-be-bound,topdown-heavy-ops,topdown-br-mispredict,topdown-fetch-lat,topdown-mem-bound}" sleep 1

 Performance counter stats for 'sleep 1':

              1.13 msec cpu-clock                        #    0.001 CPUs utilized
                 1      context-switches                 #  882.128 /sec
                 0      cpu-migrations                   #    0.000 /sec
                61      page-faults                      #   53.810 K/sec
         1,137,612      instructions                     #    1.29  insn per cycle
           881,477      cycles                           #    0.778 GHz
         2,093,496      ref-cycles                       #    1.847 G/sec
           236,356      branches                         #  208.496 M/sec
             7,090      branch-misses                    #    3.00% of all branches
         5,288,862      slots                            #    4.665 G/sec
         1,223,697      topdown-retiring                 #     23.1% Retiring
           767,403      topdown-bad-spec                 #     14.5% Bad Speculation
         2,053,322      topdown-fe-bound                 #     38.8% Frontend Bound
         1,244,438      topdown-be-bound                 #     23.5% Backend Bound
           186,665      topdown-heavy-ops                #      3.5% Heavy Operations       #     19.6% Light Operations
           725,922      topdown-br-mispredict            #     13.7% Branch Mispredict      #      0.8% Machine Clears
         1,327,400      topdown-fetch-lat                #     25.1% Fetch Latency          #     13.7% Fetch Bandwidth
           497,775      topdown-mem-bound                #      9.4% Memory Bound           #     14.1% Core Bound

       1.002701530 seconds time elapsed

       0.002744000 seconds user
       0.000000000 seconds sys

Fixes: 63e39aa6ae ("perf stat: Support L2 Topdown events")
Reviewed-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Xing Zhengjun <zhengjun.xing@linux.intel.com>
Cc: Alexander Shishkin <alexander.shishkin@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20220826140057.3289401-1-zhengjun.xing@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
History 2022-09-15 10:47:19 +02:00
arch s390/boot: fix absolute zero lowcore corruption on boot 2022-09-15 10:47:19 +02:00
block block: don't add partitions if GD_SUPPRESS_PART_SCAN is set 2022-09-15 10:47:15 +02:00
certs certs: make system keyring depend on x509 parser 2022-07-24 12:53:55 -07:00
crypto KEYS: asymmetric: enforce SM2 signature use pkey algo 2022-08-17 15:16:17 +02:00
Documentation arm64: errata: add detection for AMEVCNTR01 incrementing incorrectly 2022-09-15 10:47:08 +02:00
drivers iommu/vt-d: Fix possible recursive locking in intel_iommu_init() 2022-09-15 10:47:19 +02:00
fs btrfs: fix the max chunk size and stripe length calculation 2022-09-15 10:47:16 +02:00
include iommu/vt-d: Fix possible recursive locking in intel_iommu_init() 2022-09-15 10:47:19 +02:00
init arm64: fix rodata=full 2022-08-31 17:18:19 +02:00
io_uring lsm,io_uring: add LSM hooks for the new uring_cmd file op 2022-09-15 10:47:18 +02:00
ipc ipc: Free mq_sysctls if ipc namespace creation failed 2022-06-22 17:47:41 -05:00
kernel swiotlb: avoid potential left shift overflow 2022-09-15 10:47:18 +02:00
lib crypto: lib - remove unneeded selection of XOR_BLOCKS 2022-09-05 10:31:26 +02:00
LICENSES LICENSES/LGPL-2.1: Add LGPL-2.1-or-later as valid identifiers 2021-12-16 14:33:10 +01:00
mm Revert "mm: kmemleak: take a full lowmem check in kmemleak_*_phys()" 2022-09-15 10:47:07 +02:00
net time64.h: consolidate uses of PSEC_PER_NSEC 2022-09-15 10:47:19 +02:00
samples sample: bpf: xdp_router_ipv4: Allow the kernel to send arp requests 2022-08-17 15:14:25 +02:00
scripts kbuild: dummy-tools: avoid tmpdir leak in dummy gcc 2022-08-29 11:07:58 +02:00
security Smack: Provide read control for io_uring_cmd 2022-09-15 10:47:18 +02:00
sound ASoC: mchp-spdiftx: Fix clang -Wbitfield-constant-conversion 2022-09-15 10:47:18 +02:00
tools perf stat: Fix L2 Topdown metrics disappear for raw events 2022-09-15 10:47:19 +02:00
usr Not a lot of material this cycle. Many singleton patches against various 2022-05-27 11:22:03 -07:00
virt KVM: Unconditionally get a ref to /dev/kvm module when creating a VM 2022-08-25 11:45:05 +02:00
.clang-format clang-format: Fix space after for_each macros 2022-05-20 19:27:16 +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 kbuild: split the second line of *.mod into *.usyms 2022-05-08 03:16:59 +09:00
.mailmap ARM: SoC fixes for 5.19, part 4 2022-07-27 09:43:07 -07:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: mark ARM/PALM TREO SUPPORT orphan 2022-07-07 15:17:00 +02:00
Kbuild kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS io_uring: move to separate directory 2022-08-17 15:14:20 +02:00
Makefile kbuild: disable header exports for UML in a straightforward way 2022-09-15 10:47:18 +02:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

README 

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.