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

Jin, Yao
2021-04-21T01:18:47Z

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?

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
>