[PATCH v5 0/3] libperf: Unify scaling of counters obtained from perf_evsel__read()

[Shunsuke]

This patch series unifies the counters that can be obtained from
perf_evsel__read() to "no scaling".
The counter scaling will be done using a function moved from
tools/perf/util.

The first patch move perf_counts_values__scale from tools/perf/util
to tools/lib/perf so that it can be used with libperf.

The second patch removes the scaling process from
perf_mmap__read_self().

The third patch adds a verification test to make sure that it scales
correctly when multiplexed.

---
Previous version at:
https://lore.kernel.org/linux-perf-users/20211129090627.592149-1-nakamura.shun@xxxxxxxxxxx/

Changes in v5:
 - Update tools/lib/perf/Documentation/libperf.txt

Changes in v4:
 - Modify type s8 to type __s8

Changes in v3:
 - Move scaling process from tools/perf/util to tools/lib/perf
 - Remove scaling process from perf_mmap__read_self()
 - Remove test to verify that no division by zero occurs

Changes in v2:
 - Fix not to divide by zero when counter scaling
 - Add test to verify that no division by zero occurs


[1] https://github.com/deater/perf_event_tests/blob/master/tests/rdpmc/rdpmc_multiplexing.c


Shunsuke Nakamura (3):
  libperf: Move perf_counts_values__scale to tools/lib/perf
  libperf: Remove scaling process from perf_mmap__read_self()
  libperf tests: Add test_stat_multiplexing test

 tools/lib/perf/Documentation/libperf.txt |   2 +
 tools/lib/perf/evsel.c                   |  19 +++
 tools/lib/perf/include/perf/evsel.h      |   4 +
 tools/lib/perf/libperf.map               |   1 +
 tools/lib/perf/mmap.c                    |   2 -
 tools/lib/perf/tests/test-evlist.c       | 157 +++++++++++++++++++++++
 tools/perf/util/evsel.c                  |  19 ---
 tools/perf/util/evsel.h                  |   3 -
 8 files changed, 183 insertions(+), 24 deletions(-)

-- 
2.25.1