Re: [PATCH v3 2/2] perf arm-spe: Add support for SPE Data Source packet on AmpereOne

[Ilkka Koskinen]

On Thu, 7 Nov 2024, Leo Yan wrote:
> On Wed, Nov 06, 2024 at 07:37:40PM +0000, Ilkka Koskinen wrote:
> > Warning: EXTERNAL SENDER, use caution when opening links or attachments.
> >
> >
> > Decode SPE Data Source packets on AmpereOne. The field is IMPDEF.
> >
> > Signed-off-by: Ilkka Koskinen <ilkka@xxxxxxxxxxxxxxxxxxxxxx>
> > ---
> >  .../util/arm-spe-decoder/arm-spe-decoder.h    |  9 +++++
> >  tools/perf/util/arm-spe.c                     | 39 +++++++++++++++++++
> >  2 files changed, 48 insertions(+)
> >
> > diff --git a/tools/perf/util/arm-spe-decoder/arm-spe-decoder.h b/tools/perf/util/arm-spe-decoder/arm-spe-decoder.h
> > index 358c611eeddb..4bcd627e859f 100644
> > --- a/tools/perf/util/arm-spe-decoder/arm-spe-decoder.h
> > +++ b/tools/perf/util/arm-spe-decoder/arm-spe-decoder.h
> > @@ -67,6 +67,15 @@ enum arm_spe_common_data_source {
> >         ARM_SPE_COMMON_DS_DRAM          = 0xe,
> >  };
> >
> > +enum arm_spe_ampereone_data_source {
> > +       ARM_SPE_AMPEREONE_LOCAL_CHIP_CACHE_OR_DEVICE    = 0x0,
> > +       ARM_SPE_AMPEREONE_SLC                           = 0x3,
> > +       ARM_SPE_AMPEREONE_REMOTE_CHIP_CACHE             = 0x5,
> > +       ARM_SPE_AMPEREONE_DDR                           = 0x7,
> > +       ARM_SPE_AMPEREONE_L1D                           = 0x8,
> > +       ARM_SPE_AMPEREONE_L2D                           = 0x9,
> > +};
> > +
> >  struct arm_spe_record {
> >         enum arm_spe_sample_type type;
> >         int err;
> > diff --git a/tools/perf/util/arm-spe.c b/tools/perf/util/arm-spe.c
> > index b222557cc27a..40847a3d18b0 100644
> > --- a/tools/perf/util/arm-spe.c
> > +++ b/tools/perf/util/arm-spe.c
> > @@ -531,6 +531,44 @@ static void arm_spe__synth_data_source_common(const struct arm_spe_record *recor
> >         }
> >  }
> >
> > +/*
> > + * Source is IMPDEF. Here we convert the source code used on AmpereOne cores
> > + * to the common (Neoverse, Cortex) to avoid duplicating the decoding code.
> > + */
> > +static void arm_spe__synth_data_source_ampereone(const struct arm_spe_record *record,
> > +                                                union perf_mem_data_src *data_src)
> > +{
> > +       struct arm_spe_record common_record;
> > +
> > +       switch (record->source) {
> > +       case ARM_SPE_AMPEREONE_LOCAL_CHIP_CACHE_OR_DEVICE:
> > +               common_record.source = ARM_SPE_COMMON_DS_PEER_CORE;
> > +               break;
> > +       case ARM_SPE_AMPEREONE_SLC:
> > +               common_record.source = ARM_SPE_COMMON_DS_SYS_CACHE;
> > +               break;
> > +       case ARM_SPE_AMPEREONE_REMOTE_CHIP_CACHE:
> > +               common_record.source = ARM_SPE_COMMON_DS_REMOTE;
> > +               break;
> > +       case ARM_SPE_AMPEREONE_DDR:
> > +               common_record.source = ARM_SPE_COMMON_DS_DRAM;
> > +               break;
> > +       case ARM_SPE_AMPEREONE_L1D:
> > +               common_record.source = ARM_SPE_COMMON_DS_L1D;
> > +               break;
> > +       case ARM_SPE_AMPEREONE_L2D:
> > +               common_record.source = ARM_SPE_COMMON_DS_L2;
> > +               break;
> > +       default:
> > +               /* Assign a bogus value that's not used for common coding */
> > +               common_record.source = 0xffff;
>
> For unsupported source value, just bail out and no need to calling
> arm_spe__synth_data_source_common().
>
> It is good to use pr_warning_once() to print out warning log to remind
> users.

Hi Leo,

Makes sense, I'll do that.

--Ilkka

> Thanks,
> Leo
>
> > +               break;
> > +       }
> > +
> > +       common_record.op = record->op;
> > +       arm_spe__synth_data_source_common(&common_record, data_src);
> > +}
> > +
> >  static const struct data_src data_sources[] = {
> >         DS(MIDR_ALL_VERSIONS(MIDR_CORTEX_A720), data_source_common),
> >         DS(MIDR_ALL_VERSIONS(MIDR_CORTEX_A725), data_source_common),
> > @@ -541,6 +579,7 @@ static const struct data_src data_sources[] = {
> >         DS(MIDR_ALL_VERSIONS(MIDR_NEOVERSE_N2), data_source_common),
> >         DS(MIDR_ALL_VERSIONS(MIDR_NEOVERSE_V1), data_source_common),
> >         DS(MIDR_ALL_VERSIONS(MIDR_NEOVERSE_V2), data_source_common),
> > +       DS(MIDR_ALL_VERSIONS(MIDR_AMPERE1A), data_source_ampereone),
> >         {},
> >  };
> >
> > --
> > 2.47.0