arch-PEBS enabling for Intel platforms

Changes:
v7 -> v8:
  * Fix the warning reported by Kernel test robot (Patch 02/12)
  * Rebase code to 6.18-rc1.

v6 -> v7:
  * Rebase code to last tip perf/core tree.
  * Opportunistically remove the redundant is_x86_event() prototype.
    (Patch 01/12)
  * Fix PEBS handler NULL event access and record loss issue.
    (Patch 02/12)
  * Reset MSR_IA32_PEBS_INDEX at the head of_drain_arch_pebs() instead
    of end. It avoids the processed PEBS records are processed again in
    some corner cases like event throttling. (Patch 08/12)

v5 -> v6:
  * Rebase code to last tip perf/core tree + "x86 perf bug fixes and
    optimization" patchset
 
v4 -> v5:
  * Rebase code to 6.16-rc3
  * Allocate/free arch-PEBS buffer in callbacks *prepare_cpu/*dead_cpu
    (patch 07/10, Peter)
  * Code and comments refine (patch 09/10, Peter)


This patchset introduces architectural PEBS support for Intel platforms
like Clearwater Forest (CWF) and Panther Lake (PTL). The detailed
information about arch-PEBS can be found in chapter 11
"architectural PEBS" of "Intel Architecture Instruction Set Extensions
and Future Features".

This patch set doesn't include the SSP and SIMD regs (OPMASK/YMM/ZMM)
sampling support for arch-PEBS to avoid the dependency for the basic
SIMD regs sampling support patch series[1]. Once the basic SIMD regs
sampling is supported, the arch-PEBS based SSP and SIMD regs
(OPMASK/YMM/ZMM) sampling would be supported in a later patch set.

Tests:
  Run below tests on Clearwater Forest and Pantherlake, no issue is
  found.

  1. Basic perf counting case.
    perf stat -e '{branches,branches,branches,branches,branches,branches,branches,branches,cycles,instructions,ref-cycles}' sleep 1

  2. Basic PMI based perf sampling case.
    perf record -e '{branches,branches,branches,branches,branches,branches,branches,branches,cycles,instructions,ref-cycles}' sleep 1

  3. Basic PEBS based perf sampling case.
    perf record -e '{branches,branches,branches,branches,branches,branches,branches,branches,cycles,instructions,ref-cycles}:p' sleep 1

  4. PEBS sampling case with basic, GPRs, vector-registers and LBR groups
    perf record -e branches:p -Iax,bx,ip,xmm0 -b -c 10000 sleep 1

  5. User space PEBS sampling case with basic, GPRs and LBR groups
    perf record -e branches:p --user-regs=ax,bx,ip -b -c 10000 sleep 1

  6. PEBS sampling case with auxiliary (memory info) group
    perf mem record sleep 1

  7. PEBS sampling case with counter group
    perf record -e '{branches:p,branches,cycles}:S' -c 10000 sleep 1

  8. Perf stat and record test
    perf test 100; perf test 131


History:
  v7: https://lore.kernel.org/all/20250828013435.1528459-1-dape...
  v6: https://lore.kernel.org/all/20250821035805.159494-1-dapen... 
  v5: https://lore.kernel.org/all/20250623223546.112465-1-dapen...
  v4: https://lore.kernel.org/all/20250620103909.1586595-1-dape...
  v3: https://lore.kernel.org/all/20250415114428.341182-1-dapen...
  v2: https://lore.kernel.org/all/20250218152818.158614-1-dapen...
  v1: https://lore.kernel.org/all/20250123140721.2496639-1-dape...

Ref:
  [1]: https://lore.kernel.org/all/20250925061213.178796-1-dapen...

Dapeng Mi (12):
  perf/x86: Remove redundant is_x86_event() prototype
  perf/x86/intel: Fix NULL event access and potential PEBS record loss
  perf/x86/intel: Replace x86_pmu.drain_pebs calling with static call
  perf/x86/intel: Correct large PEBS flag check
  perf/x86/intel: Initialize architectural PEBS
  perf/x86/intel/ds: Factor out PEBS record processing code to functions
  perf/x86/intel/ds: Factor out PEBS group processing code to functions
  perf/x86/intel: Process arch-PEBS records or record fragments
  perf/x86/intel: Allocate arch-PEBS buffer and initialize PEBS_BASE MSR
  perf/x86/intel: Update dyn_constranit base on PEBS event precise level
  perf/x86/intel: Setup PEBS data configuration and enable legacy groups
  perf/x86/intel: Add counter group support for arch-PEBS

 arch/x86/events/core.c            |  21 +-
 arch/x86/events/intel/core.c      | 268 ++++++++++++-
 arch/x86/events/intel/ds.c        | 632 ++++++++++++++++++++++++------
 arch/x86/events/perf_event.h      |  41 +-
 arch/x86/include/asm/intel_ds.h   |  10 +-
 arch/x86/include/asm/msr-index.h  |  20 +
 arch/x86/include/asm/perf_event.h | 116 +++++-
 7 files changed, 963 insertions(+), 145 deletions(-)


base-commit: 3a8660878839faadb4f1a6dd72c3179c1df56787
-- 
2.34.1