perf test: Add stat uniquifying test

The `stat+uniquify.sh` test retrieves all uniquified `clockticks` events
from `perf list -v clockticks` and check if `perf stat -e clockticks -A`
contains all of them.

Committer testing:

  root@x1:~# grep -m1 "model name" /proc/cpuinfo
  model name	: 13th Gen Intel(R) Core(TM) i7-1365U
  root@x1:~# perf list clockticks

  List of pre-defined events (to be used in -e or -M):

    uncore_clock/clockticks/                           [Kernel PMU event]

  uncore memory:
    unc_m_clockticks
         [Number of clocks. Unit: uncore_imc]
  root@x1:~#
  root@x1:~# perf test uniquifying
   92: perf stat events uniquifying                    : Ok
  root@x1:~# perf test -vv uniquifying
   92: perf stat events uniquifying:
  --- start ---
  test child forked, pid 1552628
  stat event uniquifying test
  ---- end(0) ----
   92: perf stat events uniquifying                    : Ok
  root@x1:~#

Signed-off-by: Chun-Tse Shao <ctshao@google.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Dr. David Alan Gilbert <linux@treblig.org>
Cc: Howard Chu <howardchu95@gmail.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@linaro.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Levi Yun <yeoreum.yun@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Weilin Wang <weilin.wang@intel.com>
Link: https://lore.kernel.org/r/20250513215401.2315949-4-ctshao@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Author: Chun-Tse Shao

tools/perf/tests/shell/stat+event_uniquifying.sh

@@ -0,0 +1,69 @@
+#!/bin/bash
+# perf stat events uniquifying
+# SPDX-License-Identifier: GPL-2.0
+
+set -e
+
+stat_output=$(mktemp /tmp/__perf_test.stat_output.XXXXX)
+perf_tool=perf
+err=0
+
+test_event_uniquifying() {
+  # We use `clockticks` to verify the uniquify behavior.
+  event="clockticks"
+
+  # If the `-A` option is added, the event should be uniquified.
+  #
+  # $perf list -v clockticks
+  #
+  # List of pre-defined events (to be used in -e or -M):
+  #
+  #   uncore_imc_0/clockticks/                           [Kernel PMU event]
+  #   uncore_imc_1/clockticks/                           [Kernel PMU event]
+  #   uncore_imc_2/clockticks/                           [Kernel PMU event]
+  #   uncore_imc_3/clockticks/                           [Kernel PMU event]
+  #   uncore_imc_4/clockticks/                           [Kernel PMU event]
+  #   uncore_imc_5/clockticks/                           [Kernel PMU event]
+  #
+  #   ...
+  #
+  # $perf stat -e clockticks -A -- true
+  #
+  #  Performance counter stats for 'system wide':
+  #
+  # CPU0            3,773,018      uncore_imc_0/clockticks/
+  # CPU0            3,609,025      uncore_imc_1/clockticks/
+  # CPU0                    0      uncore_imc_2/clockticks/
+  # CPU0            3,230,009      uncore_imc_3/clockticks/
+  # CPU0            3,049,897      uncore_imc_4/clockticks/
+  # CPU0                    0      uncore_imc_5/clockticks/
+  #
+  #        0.002029828 seconds time elapsed
+
+  echo "stat event uniquifying test"
+  uniquified_event_array=()
+
+  # Check how many uniquified events.
+  while IFS= read -r line; do
+    uniquified_event=$(echo "$line" | awk '{print $1}')
+    uniquified_event_array+=("${uniquified_event}")
+  done < <(${perf_tool} list -v ${event} | grep "\[Kernel PMU event\]")
+
+  perf_command="${perf_tool} stat -e $event -A -o ${stat_output} -- true"
+  $perf_command
+
+  # Check the output contains all uniquified events.
+  for uniquified_event in "${uniquified_event_array[@]}"; do
+    if ! cat "${stat_output}" | grep -q "${uniquified_event}"; then
+      echo "Event is not uniquified [Failed]"
+      echo "${perf_command}"
+      cat "${stat_output}"
+      err=1
+      break
+    fi
+  done
+}
+
+test_event_uniquifying
+rm -f "${stat_output}"
+exit $err