perf arm-spe: Synthesize SPE instruction events

Synthesize instruction events for every ARM SPE record.

Arm SPE implements a hardware-based sample period, and perf implements a
software-based one. Add a warning message to inform the user of this.

Signed-off-by: German Gomez <german.gomez@arm.com>
Tested-by: Leo Yan <leo.yan@linaro.org>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: John Garry <john.garry@huawei.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Will Deacon <will@kernel.org>
Cc: linux-arm-kernel@lists.infradead.org
Link: https://lore.kernel.org/r/20211216152404.52474-1-german.gomez@arm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
German Gomez 2021-12-16 15:24:04 +00:00 committed by Arnaldo Carvalho de Melo
parent a840974e96
commit ff8752d761

View file

@ -58,6 +58,8 @@ struct arm_spe {
u8 sample_branch;
u8 sample_remote_access;
u8 sample_memory;
u8 sample_instructions;
u64 instructions_sample_period;
u64 l1d_miss_id;
u64 l1d_access_id;
@ -68,6 +70,7 @@ struct arm_spe {
u64 branch_miss_id;
u64 remote_access_id;
u64 memory_id;
u64 instructions_id;
u64 kernel_start;
@ -90,6 +93,7 @@ struct arm_spe_queue {
u64 time;
u64 timestamp;
struct thread *thread;
u64 period_instructions;
};
static void arm_spe_dump(struct arm_spe *spe __maybe_unused,
@ -202,6 +206,7 @@ static struct arm_spe_queue *arm_spe__alloc_queue(struct arm_spe *spe,
speq->pid = -1;
speq->tid = -1;
speq->cpu = -1;
speq->period_instructions = 0;
/* params set */
params.get_trace = arm_spe_get_trace;
@ -353,6 +358,35 @@ static int arm_spe__synth_branch_sample(struct arm_spe_queue *speq,
return arm_spe_deliver_synth_event(spe, speq, event, &sample);
}
static int arm_spe__synth_instruction_sample(struct arm_spe_queue *speq,
u64 spe_events_id, u64 data_src)
{
struct arm_spe *spe = speq->spe;
struct arm_spe_record *record = &speq->decoder->record;
union perf_event *event = speq->event_buf;
struct perf_sample sample = { .ip = 0, };
/*
* Handles perf instruction sampling period.
*/
speq->period_instructions++;
if (speq->period_instructions < spe->instructions_sample_period)
return 0;
speq->period_instructions = 0;
arm_spe_prep_sample(spe, speq, event, &sample);
sample.id = spe_events_id;
sample.stream_id = spe_events_id;
sample.addr = record->virt_addr;
sample.phys_addr = record->phys_addr;
sample.data_src = data_src;
sample.period = spe->instructions_sample_period;
sample.weight = record->latency;
return arm_spe_deliver_synth_event(spe, speq, event, &sample);
}
#define SPE_MEM_TYPE (ARM_SPE_L1D_ACCESS | ARM_SPE_L1D_MISS | \
ARM_SPE_LLC_ACCESS | ARM_SPE_LLC_MISS | \
ARM_SPE_REMOTE_ACCESS)
@ -482,6 +516,12 @@ static int arm_spe_sample(struct arm_spe_queue *speq)
return err;
}
if (spe->sample_instructions) {
err = arm_spe__synth_instruction_sample(speq, spe->instructions_id, data_src);
if (err)
return err;
}
return 0;
}
@ -1110,8 +1150,30 @@ arm_spe_synth_events(struct arm_spe *spe, struct perf_session *session)
return err;
spe->memory_id = id;
arm_spe_set_event_name(evlist, id, "memory");
id += 1;
}
if (spe->synth_opts.instructions) {
if (spe->synth_opts.period_type != PERF_ITRACE_PERIOD_INSTRUCTIONS) {
pr_warning("Only instruction-based sampling period is currently supported by Arm SPE.\n");
goto synth_instructions_out;
}
if (spe->synth_opts.period > 1)
pr_warning("Arm SPE has a hardware-based sample period.\n"
"Additional instruction events will be discarded by --itrace\n");
spe->sample_instructions = true;
attr.config = PERF_COUNT_HW_INSTRUCTIONS;
attr.sample_period = spe->synth_opts.period;
spe->instructions_sample_period = attr.sample_period;
err = arm_spe_synth_event(session, &attr, id);
if (err)
return err;
spe->instructions_id = id;
arm_spe_set_event_name(evlist, id, "instructions");
}
synth_instructions_out:
return 0;
}