linux-stable/tools/perf
Ian Rogers 2a939c8695 perf metric: Change divide by zero and !support events behavior
Division by zero causes expression parsing to fail and no metric to be
generated. This can mean for short running benchmarks metrics are not
shown. Change the behavior to make the value nan, which gets shown like:

'''
$ perf stat -M TopdownL2 true

 Performance counter stats for 'true':

         1,031,492      INST_RETIRED.ANY                 #      nan %  tma_fetch_bandwidth
                                                  #      nan %  tma_heavy_operations
                                                  #      nan %  tma_light_operations
            29,304      CPU_CLK_UNHALTED.REF_XCLK        #      nan %  tma_fetch_latency
                                                  #      nan %  tma_branch_mispredicts
                                                  #      nan %  tma_machine_clears
                                                  #      nan %  tma_core_bound
                                                  #      nan %  tma_memory_bound
         2,658,319      IDQ_UOPS_NOT_DELIVERED.CORE
            11,167      EXE_ACTIVITY.BOUND_ON_STORES
           262,058      EXE_ACTIVITY.1_PORTS_UTIL
     <not counted>      BR_MISP_RETIRED.ALL_BRANCHES                                            (0.00%)
     <not counted>      INT_MISC.RECOVERY_CYCLES_ANY                                            (0.00%)
     <not counted>      CPU_CLK_UNHALTED.ONE_THREAD_ACTIVE                                        (0.00%)
     <not counted>      CPU_CLK_UNHALTED.THREAD                                                 (0.00%)
     <not counted>      UOPS_RETIRED.RETIRE_SLOTS                                               (0.00%)
     <not counted>      CYCLE_ACTIVITY.STALLS_MEM_ANY                                           (0.00%)
     <not counted>      UOPS_RETIRED.MACRO_FUSED                                                (0.00%)
     <not counted>      IDQ_UOPS_NOT_DELIVERED.CYCLES_0_UOPS_DELIV.CORE                                        (0.00%)
     <not counted>      EXE_ACTIVITY.2_PORTS_UTIL                                               (0.00%)
     <not counted>      CYCLE_ACTIVITY.STALLS_TOTAL                                             (0.00%)
     <not counted>      MACHINE_CLEARS.COUNT                                                    (0.00%)
     <not counted>      UOPS_ISSUED.ANY                                                         (0.00%)

       0.002864879 seconds time elapsed

       0.003012000 seconds user
       0.000000000 seconds sys
'''

When events aren't supported a count of 0 can be confusing and make
metrics look meaningful. Change these to be nan also which, with the
next change, gets shown like:

'''
$ perf stat true
 Performance counter stats for 'true':

              1.25 msec task-clock:u                     #    0.387 CPUs utilized
                 0      context-switches:u               #    0.000 /sec
                 0      cpu-migrations:u                 #    0.000 /sec
                46      page-faults:u                    #   36.702 K/sec
           255,942      cycles:u                         #    0.204 GHz                         (88.66%)
           123,046      instructions:u                   #    0.48  insn per cycle
            28,301      branches:u                       #   22.580 M/sec
             2,489      branch-misses:u                  #    8.79% of all branches
             4,719      CPU_CLK_UNHALTED.REF_XCLK:u      #    3.765 M/sec
                                                  #      nan %  tma_frontend_bound
                                                  #      nan %  tma_retiring
                                                  #      nan %  tma_backend_bound
                                                  #      nan %  tma_bad_speculation
           344,855      IDQ_UOPS_NOT_DELIVERED.CORE:u    #  275.147 M/sec
   <not supported>      INT_MISC.RECOVERY_CYCLES_ANY:u
     <not counted>      CPU_CLK_UNHALTED.ONE_THREAD_ACTIVE:u                                        (0.00%)
     <not counted>      CPU_CLK_UNHALTED.THREAD:u                                               (0.00%)
     <not counted>      UOPS_RETIRED.RETIRE_SLOTS:u                                             (0.00%)
     <not counted>      UOPS_ISSUED.ANY:u                                                       (0.00%)

       0.003238142 seconds time elapsed

       0.000000000 seconds user
       0.003434000 seconds sys
'''

Ensure that nan metric values are quoted as nan isn't a valid number
in JSON.

Signed-off-by: Ian Rogers <irogers@google.com>
Tested-by: Kan Liang <kan.liang@linux.intel.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ahmad Yasin <ahmad.yasin@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Cc: Caleb Biggers <caleb.biggers@intel.com>
Cc: Edward Baker <edward.baker@intel.com>
Cc: Florian Fischer <florian.fischer@muhq.space>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: John Garry <john.g.garry@oracle.com>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Kang Minchul <tegongkang@gmail.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Perry Taylor <perry.taylor@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@amd.com>
Cc: Rob Herring <robh@kernel.org>
Cc: Samantha Alt <samantha.alt@intel.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Sumanth Korikkar <sumanthk@linux.ibm.com>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: Thomas Richter <tmricht@linux.ibm.com>
Cc: Tiezhu Yang <yangtiezhu@loongson.cn>
Cc: Weilin Wang <weilin.wang@intel.com>
Cc: Xing Zhengjun <zhengjun.xing@linux.intel.com>
Cc: Yang Jihong <yangjihong1@huawei.com>
Link: https://lore.kernel.org/r/20230502223851.2234828-2-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2023-05-10 12:35:02 -03:00
..
arch Disable building BPF based features by default for v6.4. 2023-05-07 11:32:18 -07:00
bench perf bench inject-buildid: Use zfree() to reduce chances of use after free 2023-04-12 10:14:01 -03:00
dlfilters perf tools: Fix usage of the verbose variable 2022-12-20 15:16:33 -03:00
Documentation perf lock contention: Update default map size to 16384 2023-04-06 21:52:27 -03:00
examples/bpf
include/perf
jvmti
pmu-events perf vendor events intel: Fix uncore topics for tigerlake 2023-04-13 18:56:18 -03:00
python
scripts perf script: Add new parameter in kfree_skb tracepoint to the python scripts using it 2023-05-02 08:36:14 -03:00
tests perf metric: Change divide by zero and !support events behavior 2023-05-10 12:35:02 -03:00
trace perf beauty: Update copy of linux/socket.h with the kernel sources 2023-01-18 10:12:23 -03:00
ui perf dso: Fix use before NULL check introduced by map__dso() introduction 2023-04-19 10:51:48 -03:00
util perf metric: Change divide by zero and !support events behavior 2023-05-10 12:35:02 -03:00
.gitignore perf jevents: Run metric_test.py at compile-time 2023-02-03 17:11:39 -03:00
Build perf script: Fix Python support when no libtraceevent 2023-03-15 10:27:07 -03:00
builtin-annotate.c perf util: Move input_name to util 2023-04-10 19:21:31 -03:00
builtin-bench.c perf bench: Add pmu-scan benchmark 2023-04-04 13:23:58 -03:00
builtin-buildid-cache.c
builtin-buildid-list.c perf util: Move input_name to util 2023-04-10 19:21:31 -03:00
builtin-c2c.c perf c2c: Use zfree() to reduce chances of use after free 2023-04-12 09:55:10 -03:00
builtin-config.c
builtin-daemon.c perf daemon: Use zfree() to reduce chances of use after free 2023-04-12 09:52:29 -03:00
builtin-data.c perf util: Move input_name to util 2023-04-10 19:21:31 -03:00
builtin-diff.c perf util: Move perf_guest/host declarations 2023-04-10 19:22:05 -03:00
builtin-evlist.c perf util: Move input_name to util 2023-04-10 19:21:31 -03:00
builtin-ftrace.c perf ftrace: Make system wide the default target for latency subcommand 2023-04-04 09:39:55 -03:00
builtin-help.c perf usage: Move usage strings 2023-04-10 19:20:53 -03:00
builtin-inject.c perf dso: Add dso__filename_with_chroot() to reduce number of accesses to dso->nsinfo members 2023-04-17 18:47:55 -03:00
builtin-kallsyms.c perf map: Add helper for ->map_ip() and ->unmap_ip() 2023-04-06 22:10:17 -03:00
builtin-kmem.c perf util: Move input_name to util 2023-04-10 19:21:31 -03:00
builtin-kvm.c perf evsel: Introduce evsel__name_is() method to check if the evsel name is equal to a given string 2023-04-24 14:28:11 -03:00
builtin-kwork.c perf util: Move input_name to util 2023-04-10 19:21:31 -03:00
builtin-list.c perf list: Use zfree() to reduce chances of use after free 2023-04-12 09:55:44 -03:00
builtin-lock.c Revert "perf build: Make BUILD_BPF_SKEL default, rename to NO_BPF_SKEL" 2023-05-06 18:07:37 -03:00
builtin-mem.c perf util: Move input_name to util 2023-04-10 19:21:31 -03:00
builtin-probe.c tools: Rename __fallthrough to fallthrough 2023-04-06 21:41:00 -03:00
builtin-record.c Revert "perf build: Make BUILD_BPF_SKEL default, rename to NO_BPF_SKEL" 2023-05-06 18:07:37 -03:00
builtin-report.c perf map: Add accessors for ->pgoff and ->reloc 2023-04-06 22:12:40 -03:00
builtin-sched.c perf sched: Fix sched latency analysis incorrection when using 'sched:sched_wakeup' 2023-04-12 19:30:39 -03:00
builtin-script.c perf dso: Fix use before NULL check introduced by map__dso() introduction 2023-04-19 10:51:48 -03:00
builtin-stat.c perf stat: Separate bperf from bpf_profiler 2023-05-05 17:30:05 -03:00
builtin-timechart.c perf util: Move input_name to util 2023-04-10 19:21:31 -03:00
builtin-top.c perf map: Add set_ methods for map->{start,end,pgoff,pgoff,reloc,erange_warned,dso,map_ip,unmap_ip,priv} 2023-04-19 12:54:41 -03:00
builtin-trace.c perf trace: Use zfree() to reduce chances of use after free 2023-04-12 09:54:32 -03:00
builtin-version.c Revert "perf build: Make BUILD_BPF_SKEL default, rename to NO_BPF_SKEL" 2023-05-06 18:07:37 -03:00
builtin.h perf usage: Move usage strings 2023-04-10 19:20:53 -03:00
check-headers.sh Disable building BPF based features by default for v6.4. 2023-05-07 11:32:18 -07:00
command-list.txt perf help: Use HAVE_LIBTRACEEVENT to filter out unsupported commands 2023-01-02 11:51:53 -03:00
CREDITS
design.txt
Makefile perf tools: Use "grep -E" instead of "egrep" 2022-12-14 15:28:19 -03:00
Makefile.config Disable building BPF based features by default for v6.4. 2023-05-07 11:32:18 -07:00
Makefile.perf Revert "perf build: Make BUILD_BPF_SKEL default, rename to NO_BPF_SKEL" 2023-05-06 18:07:37 -03:00
MANIFEST tools lib traceevent: Remove libtraceevent 2022-12-14 11:16:12 -03:00
perf-archive.sh
perf-completion.sh perf tools: Fix auto-complete on aarch64 2023-02-08 10:38:10 -03:00
perf-iostat.sh
perf-read-vdso.c
perf-sys.h
perf.c perf util: Move input_name to util 2023-04-10 19:21:31 -03:00
perf.h perf util: Move perf_guest/host declarations 2023-04-10 19:22:05 -03:00