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

["Mi, Dapeng" <dapeng1.mi@linux.intel.com>]

On 9/10/2026 9:33 PM, Arnaldo Carvalho de Melo wrote:
> On Thu, Sep 10, 2026 at 10:59:51AM +0800, 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@linux.intel.com/
>  
>> But since there are UAPI changes, these perf-tools patches would lead to
>> errors without the corresponding perf patches. 
>  
>> @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?
> That would slow down development, if it made perf kernel upstream, even
> if not yet to Linus, we can update the header in perf-tools-next, the
> check_headers script will warn about it, but now it is not running by
> default so no distracting warning and if when we decide to run it we got
> advanced warning that it will take some time to sort out, i.e. when the
> perf kernel UAPI header hits upstream and perf-tools-next merges with
> it.
>
> So send perf kernel patches to Peter and the tooling ones to me and
> Namhyung.

Got it. Thanks for the explanations. I would send the new version patch
series soon.

BTW, since the size check in copy_struct_from_user() for user space
perf_event_attr structure, the UAPI changes in the patches won't really
break the current register sampling. :)


>
> - Arnaldo
>  
>> 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@linux.intel.com/
>>> v8: https://lore.kernel.org/all/20260529082451.591783-1-dapeng1.mi@linux.intel.com/
>>> v7: https://lore.kernel.org/all/20260324005706.3778057-1-dapeng1.mi@linux.intel.com/
>>> v6: https://lore.kernel.org/all/20260209083514.2225115-1-dapeng1.mi@linux.intel.com/
>>> v5: https://lore.kernel.org/all/20251203065500.2597594-1-dapeng1.mi@linux.intel.com/
>>> v4: https://lore.kernel.org/all/20250925061213.178796-1-dapeng1.mi@linux.intel.com/
>>> v3: https://lore.kernel.org/lkml/20250815213435.1702022-1-kan.liang@linux.intel.com/
>>> v2: https://lore.kernel.org/lkml/20250626195610.405379-1-kan.liang@linux.intel.com/
>>> v1: https://lore.kernel.org/lkml/20250613134943.3186517-1-kan.liang@linux.intel.com/
>>>
>>> Ref:
>>> [1] Kernel patches of supporting eGPRs/SSP/SIMD registers sampling:
>>> https://lore.kernel.org/all/20260721062506.3745816-1-dapeng1.mi@linux.intel.com/
>>>
>>> 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