Re: [PATCH v4 00/25] perf tool: AlderLake hybrid support series 1

[Jiri Olsa <jolsa@redhat.com>]

On Wed, Apr 21, 2021 at 09:14:20AM +0800, Jin, Yao wrote:
> Hi Arnaldo, Hi Jiri,
> 
> Kan's patch series for AlderLake perf core support has been upstreamed, so
> the interface will not be changed any more.
> 
> For this perf tool series (v4), do you have any comments?

hi,
I plan to go through it this week

jirka

> 
> Thanks
> Jin Yao
> 
> On 4/16/2021 10:04 PM, Jin Yao wrote:
> > AlderLake uses a hybrid architecture utilizing Golden Cove cores
> > (core cpu) and Gracemont cores (atom cpu). Each cpu has dedicated
> > event list. Some events are available on core cpu, some events
> > are available on atom cpu and some events can be available on both.
> > 
> > Kernel exports new pmus "cpu_core" and "cpu_atom" through sysfs:
> > /sys/devices/cpu_core
> > /sys/devices/cpu_atom
> > 
> > cat /sys/devices/cpu_core/cpus
> > 0-15
> > 
> > cat /sys/devices/cpu_atom/cpus
> > 16-23
> > 
> > In this example, core cpus are 0-15 and atom cpus are 16-23.
> > 
> > To enable a core only event or atom only event:
> > 
> >          cpu_core/<event name>/
> > or
> >          cpu_atom/<event name>/
> > 
> > Count the 'cycles' event on core cpus.
> > 
> >    # perf stat -e cpu_core/cycles/ -a -- sleep 1
> > 
> >     Performance counter stats for 'system wide':
> > 
> >        12,853,951,349      cpu_core/cycles/
> > 
> >           1.002581249 seconds time elapsed
> > 
> > If one event is available on both atom cpu and core cpu, two events
> > are created automatically.
> > 
> >    # perf stat -e cycles -a -- sleep 1
> > 
> >     Performance counter stats for 'system wide':
> > 
> >        12,856,467,438      cpu_core/cycles/
> >         6,404,634,785      cpu_atom/cycles/
> > 
> >           1.002453013 seconds time elapsed
> > 
> > Group is supported if the events are from same pmu, otherwise a warning
> > is displayed and disable grouping automatically.
> > 
> >    # perf stat -e '{cpu_core/cycles/,cpu_core/instructions/}' -a -- sleep 1
> > 
> >     Performance counter stats for 'system wide':
> > 
> >        12,863,866,968      cpu_core/cycles/
> >           554,795,017      cpu_core/instructions/
> > 
> >           1.002616117 seconds time elapsed
> > 
> >    # perf stat -e '{cpu_core/cycles/,cpu_atom/instructions/}' -a -- sleep 1
> >    WARNING: events in group from different hybrid PMUs!
> >    WARNING: grouped events cpus do not match, disabling group:
> >      anon group { cpu_core/cycles/, cpu_atom/instructions/ }
> > 
> >     Performance counter stats for 'system wide':
> > 
> >             6,283,970      cpu_core/cycles/
> >               765,635      cpu_atom/instructions/
> > 
> >           1.003959036 seconds time elapsed
> > 
> > Note that, since the whole patchset for AlderLake hybrid support is very
> > large (40+ patches). For simplicity, it's splitted into several patch
> > series.
> > 
> > The patch series 1 only supports the basic functionality. The advanced
> > supports for perf-c2c/perf-mem/topdown/metrics/topology header and others
> > will be added in follow-up patch series.
> > 
> > The perf tool codes can also be found at:
> > https://github.com/yaoj/perf.git
> > 
> > v4:
> > ---
> > - In Liang Kan's patch:
> >    '[PATCH V6 21/25] perf: Extend PERF_TYPE_HARDWARE and PERF_TYPE_HW_CACHE',
> >    the user interface for hardware events and cache events are changed, so
> >    perf tool patches are changed as well.
> > 
> > - Fix an issue when atom CPUs are offlined. "/sys/bus/event_source/devices/cpu_atom/cpus"
> >    exists but the content is empty. For this case, we can't enable the cpu_atom
> >    PMU. '[PATCH v4 05/25] perf pmu: Save detected hybrid pmus to a global pmu list'
> > 
> > - Define 'ret' variable for return value in patch
> >    '[PATCH v4 09/25] perf parse-events: Create two hybrid cache events'
> > 
> > - Directly return add_raw_hybrid() in patch
> >    '[PATCH v4 10/25] perf parse-events: Create two hybrid raw events'
> > - Drop the patch 'perf pmu: Support 'cycles' and 'branches' inside
> >    hybrid PMU'.
> > 
> > - Separate '[PATCH v3 12/27] perf parse-events: Support no alias assigned event
> >    inside hybrid PMU' into two patches:
> >    '[PATCH v4 11/25] perf parse-events: Compare with hybrid pmu name'
> >    '[PATCH v4 12/25] perf parse-events: Support event inside hybrid pmu'.
> >    And these two patches are improved according to Jiri's comments.
> > 
> > v3:
> > ---
> > - Drop 'perf evlist: Hybrid event uses its own cpus'. This patch is wide
> >    and actually it's not very necessary. The current perf framework has
> >    processed the cpus for evsel well even for hybrid evsel. So this patch can
> >    be dropped.
> > 
> > - Drop 'perf evsel: Adjust hybrid event and global event mixed group'.
> >    The patch is a bit tricky and hard to understand. In v3, we will disable
> >    grouping when the group members are from different PMUs. So this patch
> >    would be not necessary.
> > 
> > - Create parse-events-hybrid.c/parse-events-hybrid.h and evlist-hybrid.c/evlist-hybrid.h.
> >    Move hybrid related codes to these files.
> > 
> > - Create a new patch 'perf pmu: Support 'cycles' and 'branches' inside hybrid PMU' to
> >    support 'cycles' and 'branches' inside PMU.
> > 
> > - Create a new patch 'perf record: Uniquify hybrid event name' to tell user the
> >    pmu which the event belongs to for perf-record.
> > 
> > - If group members are from different hybrid PMUs, shows warning and disable
> >    grouping.
> > 
> > - Other refining and refactoring.
> > 
> > v2:
> > ---
> > - Drop kernel patches (Kan posted the series "Add Alder Lake support for perf (kernel)" separately).
> > - Drop the patches for perf-c2c/perf-mem/topdown/metrics/topology header supports,
> >    which will be added in series 2 or series 3.
> > - Simplify the arguments of __perf_pmu__new_alias() by passing
> >    the 'struct pme_event' pointer.
> > - Check sysfs validity before access.
> > - Use pmu style event name, such as "cpu_core/cycles/".
> > - Move command output two chars to the right.
> > - Move pmu hybrid functions to new created pmu-hybrid.c/pmu-hybrid.h.
> >    This is to pass the perf test python case.
> > 
> > Jin Yao (25):
> >    tools headers uapi: Update tools's copy of linux/perf_event.h
> >    perf jevents: Support unit value "cpu_core" and "cpu_atom"
> >    perf pmu: Simplify arguments of __perf_pmu__new_alias
> >    perf pmu: Save pmu name
> >    perf pmu: Save detected hybrid pmus to a global pmu list
> >    perf pmu: Add hybrid helper functions
> >    perf stat: Uniquify hybrid event name
> >    perf parse-events: Create two hybrid hardware events
> >    perf parse-events: Create two hybrid cache events
> >    perf parse-events: Create two hybrid raw events
> >    perf parse-events: Compare with hybrid pmu name
> >    perf parse-events: Support event inside hybrid pmu
> >    perf record: Create two hybrid 'cycles' events by default
> >    perf stat: Add default hybrid events
> >    perf stat: Filter out unmatched aggregation for hybrid event
> >    perf stat: Warn group events from different hybrid PMU
> >    perf record: Uniquify hybrid event name
> >    perf tests: Add hybrid cases for 'Parse event definition strings' test
> >    perf tests: Add hybrid cases for 'Roundtrip evsel->name' test
> >    perf tests: Skip 'Setup struct perf_event_attr' test for hybrid
> >    perf tests: Support 'Track with sched_switch' test for hybrid
> >    perf tests: Support 'Parse and process metrics' test for hybrid
> >    perf tests: Support 'Session topology' test for hybrid
> >    perf tests: Support 'Convert perf time to TSC' test for hybrid
> >    perf tests: Skip 'perf stat metrics (shadow stat) test' for hybrid
> > 
> >   include/uapi/linux/perf_event.h            |  15 ++
> >   tools/include/uapi/linux/perf_event.h      |  15 ++
> >   tools/perf/builtin-record.c                |  47 +++++-
> >   tools/perf/builtin-stat.c                  |  29 ++++
> >   tools/perf/pmu-events/jevents.c            |   2 +
> >   tools/perf/tests/attr.c                    |   4 +
> >   tools/perf/tests/evsel-roundtrip-name.c    |  19 ++-
> >   tools/perf/tests/parse-events.c            | 152 ++++++++++++++++++
> >   tools/perf/tests/parse-metric.c            |  10 +-
> >   tools/perf/tests/perf-time-to-tsc.c        |  16 ++
> >   tools/perf/tests/shell/stat+shadow_stat.sh |   3 +
> >   tools/perf/tests/switch-tracking.c         |  10 +-
> >   tools/perf/tests/topology.c                |  10 +-
> >   tools/perf/util/Build                      |   3 +
> >   tools/perf/util/evlist-hybrid.c            |  88 ++++++++++
> >   tools/perf/util/evlist-hybrid.h            |  14 ++
> >   tools/perf/util/evlist.c                   |   5 +-
> >   tools/perf/util/evsel.c                    |  12 +-
> >   tools/perf/util/evsel.h                    |   4 +-
> >   tools/perf/util/parse-events-hybrid.c      | 178 +++++++++++++++++++++
> >   tools/perf/util/parse-events-hybrid.h      |  23 +++
> >   tools/perf/util/parse-events.c             |  86 +++++++++-
> >   tools/perf/util/parse-events.h             |   9 +-
> >   tools/perf/util/parse-events.y             |   9 +-
> >   tools/perf/util/pmu-hybrid.c               |  89 +++++++++++
> >   tools/perf/util/pmu-hybrid.h               |  22 +++
> >   tools/perf/util/pmu.c                      |  64 +++++---
> >   tools/perf/util/pmu.h                      |   7 +
> >   tools/perf/util/python-ext-sources         |   2 +
> >   tools/perf/util/stat-display.c             |  35 +++-
> >   30 files changed, 933 insertions(+), 49 deletions(-)
> >   create mode 100644 tools/perf/util/evlist-hybrid.c
> >   create mode 100644 tools/perf/util/evlist-hybrid.h
> >   create mode 100644 tools/perf/util/parse-events-hybrid.c
> >   create mode 100644 tools/perf/util/parse-events-hybrid.h
> >   create mode 100644 tools/perf/util/pmu-hybrid.c
> >   create mode 100644 tools/perf/util/pmu-hybrid.h
> > 
>