[PATCH v4 0/6] Perf tool: Support TSC for Arm64

Leo Yan leo.yan at linaro.org
Mon Sep 14 07:53:05 EDT 2020


This patch set is to refactor TSC implementation and move TSC code from
x86 folder to util/tsc.c, this allows all archs to reuse the code.  And
alse move the TSC testing from x86 folder to tests so can work as a
common testing.

So far, for x86 it needs to support cap_user_time_zero and for Arm64
it needs to support cap_user_time_short.  For architecture specific
code, every arch only needs to implement its own rdtsc() to read out
timer's counter.

This patch set has been rebased on the perf/core branch with latest
commit b1f815c479c1 ("perf vendor events power9: Add hv_24x7 core level
metric events") and tested on Arm64 DB410c.

  $ perf test list
    [...]
    68: Convert perf time to TSC
    [...]

  $ perf test 68 -v
    68: Convert perf time to TSC
    --- start ---
    test child forked, pid 10961
    mmap size 528384B
    1st event perf time 35715036563417 tsc 686221770989
    rdtsc          time 35715036649719 tsc 686221772647
    2nd event perf time 35715036660448 tsc 686221772852
    test child finished with 0
    ---- end ----
    Convert perf time to TSC: Ok

Changes from v3:
* Added comments for Arm64's rdtsc() for short counter (PeterZ);
* Rebased on latest acme/perf/core branch.

Changes from v2:
* Refactored patch set to move TSC common code to util/tsc.c (Wei/Al);
* Moved TSC testing to perf/tests (Wei);
* Dropped Arm SPE timestamp patch so can have clear purpose and easier
  reviewing; will send Arm SPE timestamp as separate patch.


Leo Yan (6):
  perf tsc: Move out common functions from x86
  perf tsc: Add rdtsc() for Arm64
  perf tsc: Calculate timestamp with cap_user_time_short
  perf tsc: Support cap_user_time_short for event TIME_CONV
  perf tests tsc: Make tsc testing as a common testing
  perf tests tsc: Add checking helper is_supported()

 tools/lib/perf/include/perf/event.h           |  4 +
 tools/perf/arch/arm64/util/Build              |  1 +
 tools/perf/arch/arm64/util/tsc.c              | 21 +++++
 tools/perf/arch/x86/include/arch-tests.h      |  1 -
 tools/perf/arch/x86/tests/Build               |  1 -
 tools/perf/arch/x86/tests/arch-tests.c        |  4 -
 tools/perf/arch/x86/util/tsc.c                | 73 +----------------
 tools/perf/tests/Build                        |  1 +
 tools/perf/tests/builtin-test.c               |  5 ++
 .../{arch/x86 => }/tests/perf-time-to-tsc.c   | 13 +++
 tools/perf/tests/tests.h                      |  2 +
 tools/perf/util/jitdump.c                     | 14 ++--
 tools/perf/util/synthetic-events.c            |  8 --
 tools/perf/util/tsc.c                         | 81 +++++++++++++++++++
 tools/perf/util/tsc.h                         |  5 ++
 15 files changed, 143 insertions(+), 91 deletions(-)
 create mode 100644 tools/perf/arch/arm64/util/tsc.c
 rename tools/perf/{arch/x86 => }/tests/perf-time-to-tsc.c (93%)

-- 
2.17.1




More information about the linux-arm-kernel mailing list