[PATCH 00/15] perf/x86: Fix sampling bugs and relax slots-event grouping

[Dapeng Mi]

This series fixes several recently discovered sampling issues:
- a warning about a missing ctx->mutex hold during LBR counter event
  initialization.
- PEBS sampling failures after CPU offline/online for both legacy PEBS
  and arch-PEBS.
- invalid counts reported by non-PEBS ACR events in SAMPLE_READ mode.
- stale or incorrect counts reported by PEBS events without counter
  snapshot support.
- incorrect event counts are seen when multiple PEBS events are active
  in a group.

It also relaxes the slots-event restriction for topdown event groups:
the slots event no longer has to be the group leader, which makes
sampling for groups containing topdown metric events more flexible.

Patch layout:
- patch 01: fix the warning triggered by for_each_sibling_event() while
  iterating LBR counter events.
- patches 02-04: fix PEBS sampling failures after CPU offline/online for
  both legacy PEBS and arch-PEBS.
- patches 05-06: fix minor PEBS handler issues.
- patch 07: fix invalid counts reported by non-PEBS ACR events in
  SAMPLE_READ mode.
- patch 08: fix stale counts reported by PEBS events without counter
  snapshot support.
- patches 09-11: refactor PEBS handlers to remove duplicated code and
  fix incorrect counts when multiple PEBS events are active in group.
- patch 12: make ACR static_call updates architectural to avoid
  model-specific updates on every platform
- patch 13: add is_x86_event() checks before testing for
  slots/topdown/mem-loads events
- patches 14-15: allow a slots event to be a non-group leader, making 
  sampling for groups containing topdown metric events more flexible.

Dapeng Mi (15):
  perf/x86/intel: Guard leader sibling walk on nr_siblings
  perf/x86/intel: Reset active_fixed_ctrl_val on CPU teardown
  perf/x86/intel: Reset active_pebs_data_cfg on CPU teardown
  perf/x86/intel: Reset cached acr_cfg_b[] and cfg_c_val[] on CPU
    teardown
  perf/x86/intel: Pass correct PEBS counter mask to no-drain update path
  perf/x86/intel: Limit PEBS counter iteration to valid array bounds
  perf/x86/intel: Reject SAMPLE_READ for no-counter-snapshot ACR events
  perf/x86/intel: Fix stale PEBS count without counter-group support
  perf/x86/intel: Refactor intel_pmu_drain_arch_pebs()
  perf/x86/intel: Refactor intel_pmu_drain_pebs_icl()
  perf/x86/intel: Fix invalid PEBS counts with counter-group support
  perf/x86/intel: Make ACR static_call update architectural
  perf/x86: Validate event type before topdown/mem-loads classification
  perf/core: Add event_caps dependency flags
  perf/x86/intel: Allow Topdown metrics with a non-leader slots event

 arch/x86/events/intel/core.c | 216 +++++++++++++++++--
 arch/x86/events/intel/ds.c   | 390 ++++++++++++++++++++++++-----------
 arch/x86/events/perf_event.h |  14 +-
 include/linux/perf_event.h   |   8 +
 kernel/events/core.c         |  52 ++++-
 5 files changed, 535 insertions(+), 145 deletions(-)


base-commit: 6350de8671b94afb7691d110f63bcda42f658a69
-- 
2.34.1