Re: [PATCH v2 0/4] Perf tool: Enable Arm arch timer counter and arm-spe's timestamp

From: Mathieu Poirier
Date: Wed Aug 12 2020 - 12:07:10 EST


Hi Arnaldo,

On Fri, 7 Aug 2020 at 01:16, Leo Yan <leo.yan@xxxxxxxxxx> wrote:
>
> This patch set is to enable Arm arch timer counter and Arm SPE is the
> first customer to use arch timer counter for its timestamp.
>
> Patches 01 ~ 03 enables Arm arch timer counter in Perf tool; patch 01 is
> to retrieve arch timer's parameters from mmaped page; patch 02 provides
> APIs for the conversion between arch timer's counter and time; patch 03
> adds a test for patches 01 and 02.
>
> As the first customer to use Arm arch timer counter in perf tool, patch
> 04 is to generate sample's timestamp for ARM SPE AUX trace data.
>
> This patch set has been rebased on perf/core branch with the latest
> commit c4735d990268 ("perf evsel: Don't set
> sample_regs_intr/sample_regs_user for dummy event").

The ARM SPE perf tools code is orphan and I don't have the cycles to
pick it up. Leo has spent a lot of time in that code and as such I
suggest that he starts maintaining it, probably following the same
kind of arrangement you and I have for coresight.

Thanks,
Mathieu

>
> After changes:
>
> # perf test 67 -v
> 67: Convert perf time to arch timer counter
> --- start ---
> test child forked, pid 5463
> mmap size 528384B
> 1st event perf time 2231755083020 arch timer cnt 113097053477
> test time 2231755087460 arch timer cnt 113097053699
> 2nd event perf time 2231755090680 arch timer cnt 113097053860
> test child finished with 0
> ---- end ----
>
> Reports the SPE sample with timestamp:
>
> $ perf script -F,+time
> dd 6799 [034] 25496.733475: 1 l1d-access: ffff87f37b88 _dl_start+0x288 (/usr/lib/aarch64-linux-gnu/ld-2.28.so)
> dd 6799 [034] 25496.733475: 1 tlb-access: ffff87f37b88 _dl_start+0x288 (/usr/lib/aarch64-linux-gnu/ld-2.28.so)
> dd 6799 [034] 25496.733479: 1 l1d-access: ffff87f37c74 _dl_start+0x374 (/usr/lib/aarch64-linux-gnu/ld-2.28.so)
> dd 6799 [034] 25496.733479: 1 tlb-access: ffff87f37c74 _dl_start+0x374 (/usr/lib/aarch64-linux-gnu/ld-2.28.so)
> dd 6799 [034] 25496.733485: 1 l1d-access: ffff87f49af4 __GI___tunables_init+0x3c (/usr/lib/aarch64-linux-gnu/ld-2.28.so)
> dd 6799 [034] 25496.733485: 1 tlb-access: ffff87f49af4 __GI___tunables_init+0x3c (/usr/lib/aarch64-linux-gnu/ld-2.28.so)
>
> Changes from v1:
> * Rebased on the latest perf/core branch;
> * Added a testing for Arm timer counter conversion (Ian Rogers).
>
>
> Leo Yan (4):
> perf tools: Support Arm arch timer counter
> perf arm_arch_timer: Convert between counter and timestamp
> perf arm_arch_timer: Test conversion between counter and timestamp
> perf arm-spe: Enable timestamp with arch timer counter
>
> tools/perf/arch/arm64/include/arch-tests.h | 6 +
> tools/perf/arch/arm64/tests/Build | 1 +
> tools/perf/arch/arm64/tests/arch-tests.c | 4 +
> .../tests/perf-time-to-arch-timer-counter.c | 189 ++++++++++++++++++
> tools/perf/arch/arm64/util/Build | 1 +
> tools/perf/arch/arm64/util/arch_timer.c | 50 +++++
> tools/perf/arch/arm64/util/arm-spe.c | 17 ++
> tools/perf/util/Build | 1 +
> tools/perf/util/arm-spe.c | 16 +-
> tools/perf/util/arm-spe.h | 5 +
> tools/perf/util/arm_arch_timer.c | 28 +++
> tools/perf/util/arm_arch_timer.h | 23 +++
> 12 files changed, 339 insertions(+), 2 deletions(-)
> create mode 100644 tools/perf/arch/arm64/tests/perf-time-to-arch-timer-counter.c
> create mode 100644 tools/perf/arch/arm64/util/arch_timer.c
> create mode 100644 tools/perf/util/arm_arch_timer.c
> create mode 100644 tools/perf/util/arm_arch_timer.h
>
> --
> 2.17.1
>