Messages in this thread | | | From | James Clark <> | Subject | [PATCH 0/4] Enable display of partial and empty SVE predicates from Arm SPE data | Date | Mon, 19 Dec 2022 16:12:54 +0000 |
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Hi,
I'm submitting this on behalf of German who moved on to work on other things in Arm before he could finish it off.
The predicate information is available on SPE samples from Armv8.3 (FEAT_SPEv1p1), this could be useful info for profiling SVE code as partial and empty predicates indicate that the full vector width isn't being used. There is a good example in the last commit message.
Though currently, there isn't a suitable field to store the info on Perf samples, so this change also adds a new SIMD field. This field could be used by other architectures, but currently there is only one bit reserved to identify SVE. It's only added to struct perf_sample on the userspace side, and isn't part of the kernel ABI, so it doesn't survive a perf inject. Although this is the same behavior for some other fields like branch flags, so I don't think it should be an issue to do something similar here. Perhaps in the future we could make sure everything that is synthesised from auxtrace data also makes it back into the new Perf inject file without being lost.
German Gomez (4): perf event: Add simd_flags field to perf_sample perf arm-spe: Refactor arm-spe to support operation packet type perf arm-spe: Add SVE flags to the SPE samples perf report: Add 'simd' sort field
tools/perf/Documentation/perf-report.txt | 1 + .../util/arm-spe-decoder/arm-spe-decoder.c | 30 ++++++++++-- .../util/arm-spe-decoder/arm-spe-decoder.h | 47 +++++++++++++++---- tools/perf/util/arm-spe.c | 28 +++++++++-- tools/perf/util/hist.c | 1 + tools/perf/util/hist.h | 1 + tools/perf/util/sample.h | 13 +++++ tools/perf/util/sort.c | 47 +++++++++++++++++++ tools/perf/util/sort.h | 2 + 9 files changed, 152 insertions(+), 18 deletions(-)
base-commit: 573de010917836f198a4e579d40674991659668b -- 2.25.1
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