[PATCH v4 0/3] 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/20211109085831.3770594-1-nakamura.shun@xxxxxxxxxxx/


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 scaling process for 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/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 -
 7 files changed, 181 insertions(+), 24 deletions(-)

-- 
2.25.1