[PATCH v2 5/6] perf cs-etm: Use existing decoder instead of resetting it

From: James Clark
Date: Wed Jul 21 2021 - 11:04:41 EST


When dumping trace, the decoder is continually deleted and recreated to
decode each buffer. To support both formatted and unformatted trace in
a later commit, the decoder will be configured in advance.

This commit removes the deletion of the decoder and allows the
formatted/unformatted setting to persist.

Reviewed-by: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
Signed-off-by: James Clark <james.clark@xxxxxxx>
---
tools/perf/util/cs-etm.c | 37 +++++++------------------------------
1 file changed, 7 insertions(+), 30 deletions(-)

diff --git a/tools/perf/util/cs-etm.c b/tools/perf/util/cs-etm.c
index 2d07e52ffd3c..760050ea936d 100644
--- a/tools/perf/util/cs-etm.c
+++ b/tools/perf/util/cs-etm.c
@@ -508,14 +508,11 @@ static int cs_etm__init_decoder_params(struct cs_etm_decoder_params *d_params,
return ret;
}

-static void cs_etm__dump_event(struct cs_etm_auxtrace *etm,
+static void cs_etm__dump_event(struct cs_etm_queue *etmq,
struct auxtrace_buffer *buffer)
{
int ret;
const char *color = PERF_COLOR_BLUE;
- struct cs_etm_decoder_params d_params;
- struct cs_etm_trace_params *t_params;
- struct cs_etm_decoder *decoder;
size_t buffer_used = 0;

fprintf(stdout, "\n");
@@ -523,29 +520,11 @@ static void cs_etm__dump_event(struct cs_etm_auxtrace *etm,
". ... CoreSight ETM Trace data: size %zu bytes\n",
buffer->size);

- /* Use metadata to fill in trace parameters for trace decoder */
- t_params = zalloc(sizeof(*t_params) * etm->num_cpu);
-
- if (!t_params)
- return;
-
- if (cs_etm__init_trace_params(t_params, etm))
- goto out_free;
-
- /* Set decoder parameters to simply print the trace packets */
- if (cs_etm__init_decoder_params(&d_params, NULL,
- CS_ETM_OPERATION_PRINT))
- goto out_free;
-
- decoder = cs_etm_decoder__new(etm->num_cpu, &d_params, t_params);
-
- if (!decoder)
- goto out_free;
do {
size_t consumed;

ret = cs_etm_decoder__process_data_block(
- decoder, buffer->offset,
+ etmq->decoder, buffer->offset,
&((u8 *)buffer->data)[buffer_used],
buffer->size - buffer_used, &consumed);
if (ret)
@@ -554,10 +533,7 @@ static void cs_etm__dump_event(struct cs_etm_auxtrace *etm,
buffer_used += consumed;
} while (buffer_used < buffer->size);

- cs_etm_decoder__free(decoder);
-
-out_free:
- zfree(&t_params);
+ cs_etm_decoder__reset(etmq->decoder);
}

static int cs_etm__flush_events(struct perf_session *session,
@@ -769,7 +745,8 @@ static struct cs_etm_queue *cs_etm__alloc_queue(struct cs_etm_auxtrace *etm)

/* Set decoder parameters to decode trace packets */
if (cs_etm__init_decoder_params(&d_params, etmq,
- CS_ETM_OPERATION_DECODE))
+ dump_trace ? CS_ETM_OPERATION_PRINT :
+ CS_ETM_OPERATION_DECODE))
goto out_free;

etmq->decoder = cs_etm_decoder__new(etm->num_cpu, &d_params, t_params);
@@ -2422,7 +2399,7 @@ static void dump_queued_data(struct cs_etm_auxtrace *etm,
for (i = 0; i < etm->queues.nr_queues; ++i)
list_for_each_entry(buf, &etm->queues.queue_array[i].head, list)
if (buf->reference == event->reference)
- cs_etm__dump_event(etm, buf);
+ cs_etm__dump_event(etm->queues.queue_array[i].priv, buf);
}

static int cs_etm__process_auxtrace_event(struct perf_session *session,
@@ -2460,7 +2437,7 @@ static int cs_etm__process_auxtrace_event(struct perf_session *session,

if (dump_trace)
if (auxtrace_buffer__get_data(buffer, fd)) {
- cs_etm__dump_event(etm, buffer);
+ cs_etm__dump_event(etm->queues.queue_array[idx].priv, buffer);
auxtrace_buffer__put_data(buffer);
}
} else if (dump_trace)
--
2.28.0