On Mon, 6 Feb 2023 14:51:45 +0800
Jie Zhan <zhanjie9@xxxxxxxxxxxxx> wrote:
> Support for HiSilicon PMCU data recording using 'perf-record'.
>
> Users can start PMCU profiling through 'perf-record'. Event numbers are
> passed by a sysfs interface. The following optional parameters can be
> passed through 'perf-record':
> - nr_sample: number of samples to take
> - sample_period_ms: time in ms for PMU counters to stay on for an event
> - pmccfiltr: bits[31-24] of system register PMCCFILTR_EL0
>
> Example usage:
>
> 1. Enter event numbers in the 'user_events' file:
>
> echo "0x10 0x11" > /sys/devices/hisi_pmcu_sccl3/user_events
>
> 2. Start the sampling with 'perf-record':
>
> perf record -e hisi_pmcu_sccl3/nr_sample=1000,sample_period_ms=1/
>
> In this example, the PMCU takes 1000 samples of event 0x0010 and 0x0011
> with a sampling period of 1ms. Data will be written to a 'perf.data' file.
>
> Co-developed-by: Yang Shen <shenyang39@xxxxxxxxxx>
> Signed-off-by: Yang Shen <shenyang39@xxxxxxxxxx>
> Signed-off-by: Jie Zhan <zhanjie9@xxxxxxxxxxxxx>
I'm not particularly knowledgeable about perf tool so just some superficial comments
from me.
> ---
> diff --git a/tools/perf/arch/arm64/util/hisi-pmcu.c b/tools/perf/arch/arm64/util/hisi-pmcu.c
> new file mode 100644
> index 000000000000..7c33abf1182d
> --- /dev/null
> +++ b/tools/perf/arch/arm64/util/hisi-pmcu.c
> +struct hisi_pmcu_record {
> + struct auxtrace_record itr;
> + struct perf_pmu *hisi_pmcu_pmu;
> + struct evlist *evlist;
> +};
...
> +struct auxtrace_record *hisi_pmcu_recording_init(int *err,
> + struct perf_pmu *hisi_pmcu_pmu)
> +{
...
> + pmcu_record->hisi_pmcu_pmu = hisi_pmcu_pmu;
> + pmcu_record->itr.recording_options = hisi_pmcu_recording_options;
> + pmcu_record->itr.info_priv_size = hisi_pmcu_info_priv_size;
> + pmcu_record->itr.info_fill = hisi_pmcu_info_fill;
> + pmcu_record->itr.free = hisi_pmcu_record_free;
> + pmcu_record->itr.reference = hisi_pmcu_reference;
> + pmcu_record->itr.read_finish = auxtrace_record__read_finish;
> + pmcu_record->itr.alignment = HISI_PMCU_DATA_ALIGNMENT;
> + pmcu_record->itr.pmu = hisi_pmcu_pmu;
Maybe a local variable for itr - or if you can rely on c99 in perf tool
a compound literal to use structure field names etc.
pmcu_record->itr = (struct xxx){
.recording_options = ,
etc
> +
> + *err = 0;
> + return &pmcu_record->itr;
> +}
> diff --git a/tools/perf/util/hisi-pmcu.h b/tools/perf/util/hisi-pmcu.h
> new file mode 100644
> index 000000000000..d46d523a3aee
> --- /dev/null
> +++ b/tools/perf/util/hisi-pmcu.h
> @@ -0,0 +1,17 @@
> +/* SPDX-License-Identifier: GPL-2.0-only */
> +/*
> + * HiSilicon Performance Monitor Control Unit (PMCU) support
> + *
> + * Copyright (C) 2022 HiSilicon Limited
Probably want to update the dates if any substantial changes for v2.
