Re: [Patch v10 00/10] Perf tools: Support eGPRs/SSP/SIMD registers sampling

[Mi, Dapeng]

On 9/10/2026 10:59 AM, Mi, Dapeng wrote:
> Peter queued the dependent perf patches into the tip perf/core tree.
>
> https://lore.kernel.org/all/20260824082731.1013973-1-dapeng1.mi@xxxxxxxxxxxxxxx/
>
> But since there are UAPI changes, these perf-tools patches would lead to
> errors without the corresponding perf patches. 

The statement looks wrong. I tried to run these perf tools patches on DMR
with the old kernel, no issues are found.

# ./perf record -I?
available registers: AX BX CX DX SI DI BP SP IP FLAGS CS SS R8 R9 R10 R11
R12 R13 R14 R15 XMM0 XMM1 XMM2 XMM3 XMM4 XMM5 XMM6 XMM7 XMM8 XMM9 XMM10
XMM11 XMM12 XMM13 XMM14 XMM15

# ./perf record --user-regs=?
available registers: AX BX CX DX SI DI BP SP IP FLAGS CS SS R8 R9 R10 R11
R12 R13 R14 R15

The copy_struct_from_user() in perf_copy_attr() would reject any new
non-zero field in user space perf_event_attr structure and this would
ensure perf tools falls back to the legacy register list.

So it looks we don't need to wait for next release cycle and I would rebase
and send new patch series. 

Thanks.


>
> @Arnaldo, @Namhyung, @Ian how would we handle such kind of dependency
> issues generally? Wait for the dependent perf patches merged into mainline
> and then merge the perf-tools patches?
>
> Thanks.
>
>
> On 7/21/2026 3:26 PM, Dapeng Mi wrote:
>> Patch layout:
>> - Patches 1-2: Fix two bugs in DWARF register bounds checking and event
>>   attribute printing/swapping.
>> - Patches 3-4: Sync tools and perf headers with the kernel sources.
>> - Patches 5-8: Add SIMD/eGPR/SSP sampling and dump support.
>> - Patches 9-10: Add unit tests for SIMD/eGPR/SSP sampling.
>>
>> Changes since v9:
>> - Patch 05/10: Fix the issue that cpu-clock/task-clock fails to sample
>>   GPRs.
>> - Patch 06/10: Ensure sample_intr_{pred|vec}_regs and
>>   sample_user_{pred|vec}_regs to keep identical if both are set since
>>   they share sample_{pred|vec}_reg_qwords.
>>
>> Changes since v8:
>> - Patch 01/10: Fix incorrect DWARF register bounds checking.
>> - Patch 02/10: Add missing event attribute printing and swapping support
>>   (Sashiko).
>> - Patch 07/10: Remove dead code ([idx++]) in SIMD register dumping
>>   (Sashiko).
>> - Patch 08/10: Restore the original x86 libdw_frame_nregs value (17), as
>>   libdw still lacks x86 SIMD/eGPR support (Ian).
>> - Patch 09/10: Add x86 eGPR/SSP sampling unit tests (Ian).
>> - Patch 10/10: Add x86 SIMD register sampling unit tests (Ian).
>>
>> Changes since v7:
>> - Address Sashiko's comments including,
>>   * documents are not update availably; SIMD registers bitmask may be
>>     overwritten by shorter mask; u16 type in sample meta-data break the
>>     cross-endian conversion, etc.
>> - Add SIMD/eGPRs/SSP support in dwarf-regs (Ian).
>> - Misc enhancements.
>>
>> Changes since v6:
>> - Address Ian's comments including,
>>   * Add more comments for newly added register indexes (patch 1/4).
>>   * Several minor enhancements in patch 4/4.
>> - Limit dwarf minimal regs to legacy GPRs (excluding APX eGPRs)
>>   (patch 2/4).
>>
>> Changes since v5:
>> - Split the sampling support for eGPRs/SSP registers and SIMD registers
>>   into 2 patches.
>> - Address Ian's comments including,
>>   * Convert the architecture dependent functions into regular
>>     architectural independent functions, like whatperf_reg_name() does.
>>   * Refine the functions name to represent what the functions really do.
>>   * Add comments for some key functions arguments.
>>   * Misc enhancements.
>>
>> This patch-set adds sampling support for x86 eGPRs/SSP/SIMD registers in
>> perf tools base on the corresponding sampling support for eGPRs/SSP/SIMD
>> registers in kernel[1]. In versions before v6, these perf-tools patches
>> are integrated as a whole patch-set with the kernel patches, but it's
>> split and posted to an independent perf-tools patch-set for convenient
>> review.
>>
>> History:
>> v9: https://lore.kernel.org/all/20260706023444.3067660-1-dapeng1.mi@xxxxxxxxxxxxxxx/
>> v8: https://lore.kernel.org/all/20260529082451.591783-1-dapeng1.mi@xxxxxxxxxxxxxxx/
>> v7: https://lore.kernel.org/all/20260324005706.3778057-1-dapeng1.mi@xxxxxxxxxxxxxxx/
>> v6: https://lore.kernel.org/all/20260209083514.2225115-1-dapeng1.mi@xxxxxxxxxxxxxxx/
>> v5: https://lore.kernel.org/all/20251203065500.2597594-1-dapeng1.mi@xxxxxxxxxxxxxxx/
>> v4: https://lore.kernel.org/all/20250925061213.178796-1-dapeng1.mi@xxxxxxxxxxxxxxx/
>> v3: https://lore.kernel.org/lkml/20250815213435.1702022-1-kan.liang@xxxxxxxxxxxxxxx/
>> v2: https://lore.kernel.org/lkml/20250626195610.405379-1-kan.liang@xxxxxxxxxxxxxxx/
>> v1: https://lore.kernel.org/lkml/20250613134943.3186517-1-kan.liang@xxxxxxxxxxxxxxx/
>>
>> Ref:
>> [1] Kernel patches of supporting eGPRs/SSP/SIMD registers sampling:
>> https://lore.kernel.org/all/20260721062506.3745816-1-dapeng1.mi@xxxxxxxxxxxxxxx/
>>
>> Dapeng Mi (10):
>>   perf dwarf-regs: Fix DWARF register index bounds check
>>   perf util: Add missed fields in _attr__fprintf() and __attr_swap()
>>   tools headers: Sync x86 headers with kernel sources
>>   perf headers: Sync perf_event.h/perf_regs.h with the kernel headers
>>   perf regs: Support x86 eGPRs/SSP sampling
>>   perf regs: Support x86 SIMD registers sampling
>>   perf regs: Enable dumping of SIMD registers
>>   perf dwarf-regs: Add SIMD/eGPRs support for x86 DWARF registers
>>   perf tests: Add x86 eGPRs/SSP registers sampling test
>>   perf tests: Add SIMD registers sampling test
>>
>>  tools/arch/x86/include/asm/msr-index.h        |   7 +
>>  tools/arch/x86/include/uapi/asm/perf_regs.h   |  53 +++
>>  tools/include/uapi/linux/perf_event.h         |  49 +-
>>  tools/perf/Documentation/perf-record.txt      |  10 +-
>>  tools/perf/builtin-script.c                   |  93 +++-
>>  tools/perf/tests/shell/record.sh              | 257 +++++++++++
>>  .../util/dwarf-regs-arch/dwarf-regs-csky.c    |   2 +-
>>  .../util/dwarf-regs-arch/dwarf-regs-powerpc.c |   2 +-
>>  .../util/dwarf-regs-arch/dwarf-regs-s390.c    |   2 +-
>>  .../util/dwarf-regs-arch/dwarf-regs-x86.c     | 140 +++++-
>>  tools/perf/util/dwarf-regs.c                  |   9 +-
>>  tools/perf/util/evsel.c                       | 106 ++++-
>>  tools/perf/util/evsel.h                       |   7 +
>>  tools/perf/util/header.c                      |   3 +-
>>  tools/perf/util/include/dwarf-regs.h          |   7 +-
>>  tools/perf/util/parse-regs-options.c          | 210 ++++++++-
>>  .../perf/util/perf-regs-arch/perf_regs_x86.c  | 436 +++++++++++++++++-
>>  tools/perf/util/perf_event_attr_fprintf.c     |  13 +
>>  tools/perf/util/perf_regs.c                   |  84 +++-
>>  tools/perf/util/perf_regs.h                   |  21 +-
>>  tools/perf/util/record.h                      |   7 +
>>  tools/perf/util/sample.h                      |   5 +
>>  .../scripting-engines/trace-event-python.c    | 127 ++++-
>>  tools/perf/util/session.c                     | 112 ++++-
>>  tools/perf/util/synthetic-events.c            |  38 ++
>>  tools/perf/util/unwind-libdw.c                |   6 +-
>>  26 files changed, 1696 insertions(+), 110 deletions(-)
>>
>>
>> base-commit: e01c7bd5b1eece254bcbf282db066b12c4815d21