Re: [PATCH v3 07/10] pert tools: Add queue management functionality

[Robert Walker <robert.walker@arm.com>]

On 01/17/2018 05:52 PM, Mathieu Poirier wrote:
> Add functionatlity to setup trace queues so that traces associated with
> CoreSight auxtrace events found in the perf.data file can be classified
> properly.  The decoder and memory callback associated with each queue are
> then used to decode the traces that have been assigned to that queue.
> 
> Co-authored-by: Tor Jeremiassen <tor@ti.com>
> Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
> ---
>   tools/perf/util/cs-etm.c | 208 ++++++++++++++++++++++++++++++++++++++++++++++-
>   1 file changed, 204 insertions(+), 4 deletions(-)
> 
> diff --git a/tools/perf/util/cs-etm.c b/tools/perf/util/cs-etm.c
> index cad429ce3c00..83eb676274b5 100644
> --- a/tools/perf/util/cs-etm.c
> +++ b/tools/perf/util/cs-etm.c
> @@ -196,15 +196,215 @@ static void cs_etm__free(struct perf_session *session)
>   	zfree(&aux);
>   }
>   
> +static u32 cs_etm__mem_access(struct cs_etm_queue *etmq, u64 address,
> +			      size_t size, u8 *buffer)
> +{
> +	u8  cpumode;
> +	u64 offset;
> +	int len;
> +	struct	 thread *thread;
> +	struct	 machine *machine;
> +	struct	 addr_location al;
> +
> +	if (!etmq)
> +		return -1;
> +
> +	machine = etmq->etm->machine;
> +	if (address >= etmq->etm->kernel_start)
> +		cpumode = PERF_RECORD_MISC_KERNEL;
> +	else
> +		cpumode = PERF_RECORD_MISC_USER;
> +
> +	thread = etmq->thread;
> +	if (!thread) {
> +		if (cpumode != PERF_RECORD_MISC_KERNEL)
> +			return -EINVAL;
> +		thread = etmq->etm->unknown_thread;
> +	}
> +
> +	thread__find_addr_map(thread, cpumode, MAP__FUNCTION, address, &al);
> +
> +	if (!al.map || !al.map->dso)
> +		return 0;
> +
> +	if (al.map->dso->data.status == DSO_DATA_STATUS_ERROR &&
> +	    dso__data_status_seen(al.map->dso, DSO_DATA_STATUS_SEEN_ITRACE))
> +		return 0;
> +
> +	offset = al.map->map_ip(al.map, address);
> +
> +	map__load(al.map);
> +
> +	len = dso__data_read_offset(al.map->dso, machine, offset, buffer, size);
> +
> +	if (len <= 0)
> +		return 0;
> +
> +	return len;
> +}
> +
> +static struct cs_etm_queue *cs_etm__alloc_queue(struct cs_etm_auxtrace *etm,
> +						unsigned int queue_nr)
> +{
> +	int i;
> +	struct cs_etm_decoder_params d_params;
> +	struct cs_etm_trace_params  *t_params;
> +	struct cs_etm_queue *etmq;
> +
> +	etmq = zalloc(sizeof(*etmq));
> +	if (!etmq)
> +		return NULL;
> +
> +	etmq->event_buf = malloc(PERF_SAMPLE_MAX_SIZE);

Should this and the other members of etmq alloc'd in this function be 
free'd in cs_etm__free_queue() as they were in the original version at
https://github.com/Linaro/perf-opencsd/ ?  I can't see them getting 
freed anywhere else.

> +	if (!etmq->event_buf)
> +		goto out_free;
> +
> +	etmq->etm = etm;
> +	etmq->queue_nr = queue_nr;
> +	etmq->pid = -1;
> +	etmq->tid = -1;
> +	etmq->cpu = -1;
> +
> +	/* Use metadata to fill in trace parameters for trace decoder */
> +	t_params = zalloc(sizeof(*t_params) * etm->num_cpu);
> +
> +	if (!t_params)
> +		goto out_free;
> +
> +	for (i = 0; i < etm->num_cpu; i++) {
> +		t_params[i].protocol = CS_ETM_PROTO_ETMV4i;
> +		t_params[i].etmv4.reg_idr0 = etm->metadata[i][CS_ETMV4_TRCIDR0];
> +		t_params[i].etmv4.reg_idr1 = etm->metadata[i][CS_ETMV4_TRCIDR1];
> +		t_params[i].etmv4.reg_idr2 = etm->metadata[i][CS_ETMV4_TRCIDR2];
> +		t_params[i].etmv4.reg_idr8 = etm->metadata[i][CS_ETMV4_TRCIDR8];
> +		t_params[i].etmv4.reg_configr =
> +					etm->metadata[i][CS_ETMV4_TRCCONFIGR];
> +		t_params[i].etmv4.reg_traceidr =
> +					etm->metadata[i][CS_ETMV4_TRCTRACEIDR];
> +	}
> +
> +	/* Set decoder parameters to simply print the trace packets */
> +	d_params.packet_printer = cs_etm__packet_dump;
> +	d_params.operation = CS_ETM_OPERATION_DECODE;
> +	d_params.formatted = true;
> +	d_params.fsyncs = false;
> +	d_params.hsyncs = false;
> +	d_params.frame_aligned = true;
> +	d_params.data = etmq;
> +
> +	etmq->decoder = cs_etm_decoder__new(etm->num_cpu, &d_params, t_params);
> +
> +	zfree(&t_params);
> +
> +	if (!etmq->decoder)
> +		goto out_free;
> +
> +	/*
> +	 * Register a function to handle all memory accesses required by
> +	 * the trace decoder library.
> +	 */
> +	if (cs_etm_decoder__add_mem_access_cb(etmq->decoder,
> +					      0x0L, ((u64) -1L),
> +					      cs_etm__mem_access))
> +		goto out_free_decoder;
> +
> +	etmq->offset = 0;
> +
> +	return etmq;
> +
> +out_free_decoder:
> +	cs_etm_decoder__free(etmq->decoder);
> +out_free:
> +	zfree(&etmq->event_buf);
> +	free(etmq);
> +
> +	return NULL;
> +}
> +
> +static int cs_etm__setup_queue(struct cs_etm_auxtrace *etm,
> +			       struct auxtrace_queue *queue,
> +			       unsigned int queue_nr)
> +{
> +	struct cs_etm_queue *etmq = queue->priv;
> +
> +	if (list_empty(&queue->head) || etmq)
> +		return 0;
> +
> +	etmq = cs_etm__alloc_queue(etm, queue_nr);
> +
> +	if (!etmq)
> +		return -ENOMEM;
> +
> +	queue->priv = etmq;
> +
> +	if (queue->cpu != -1)
> +		etmq->cpu = queue->cpu;
> +
> +	etmq->tid = queue->tid;
> +
> +	return 0;
> +}
> +
> +static int cs_etm__setup_queues(struct cs_etm_auxtrace *etm)
> +{
> +	unsigned int i;
> +	int ret;
> +
> +	for (i = 0; i < etm->queues.nr_queues; i++) {
> +		ret = cs_etm__setup_queue(etm, &etm->queues.queue_array[i], i);
> +		if (ret)
> +			return ret;
> +	}
> +
> +	return 0;
> +}
> +
> +static int cs_etm__update_queues(struct cs_etm_auxtrace *etm)
> +{
> +	if (etm->queues.new_data) {
> +		etm->queues.new_data = false;
> +		return cs_etm__setup_queues(etm);
> +	}
> +
> +	return 0;
> +}
> +
>   static int cs_etm__process_event(struct perf_session *session,
>   				 union perf_event *event,
>   				 struct perf_sample *sample,
>   				 struct perf_tool *tool)
>   {
> -	(void) session;
> -	(void) event;
> -	(void) sample;
> -	(void) tool;
> +	int err = 0;
> +	u64 timestamp;
> +	struct cs_etm_auxtrace *etm = container_of(session->auxtrace,
> +						   struct cs_etm_auxtrace,
> +						   auxtrace);
> +
> +	/* Keep compiler happy */
> +	(void)event;
> +
> +	if (dump_trace)
> +		return 0;
> +
> +	if (!tool->ordered_events) {
> +		pr_err("CoreSight ETM Trace requires ordered events\n");
> +		return -EINVAL;
> +	}
> +
> +	if (!etm->timeless_decoding)
> +		return -EINVAL;
> +
> +	if (sample->time && (sample->time != (u64) -1))
> +		timestamp = sample->time;
> +	else
> +		timestamp = 0;
> +
> +	if (timestamp || etm->timeless_decoding) {
> +		err = cs_etm__update_queues(etm);
> +		if (err)
> +			return err;
> +	}
> +
>   	return 0;
>   }
>   
>