Re: [PATCH 05/10] perf tools: Add support for decoding CoreSight trace data

[Leo Yan]

Hi Mathieu, Mike,

On Fri, Dec 15, 2017 at 09:44:54AM -0700, Mathieu Poirier wrote:
> Adding functionality to create a CoreSight trace decoder capable
> of decoding trace data pushed by a client application.
> 
> Co-authored-by: Tor Jeremiassen <tor@xxxxxx>
> Signed-off-by: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
> ---
>  tools/perf/util/cs-etm-decoder/cs-etm-decoder.c | 119 ++++++++++++++++++++++++
>  1 file changed, 119 insertions(+)
> 
> diff --git a/tools/perf/util/cs-etm-decoder/cs-etm-decoder.c b/tools/perf/util/cs-etm-decoder/cs-etm-decoder.c
> index 6a4c86b1431f..57b020b0b36f 100644
> --- a/tools/perf/util/cs-etm-decoder/cs-etm-decoder.c
> +++ b/tools/perf/util/cs-etm-decoder/cs-etm-decoder.c
> @@ -200,6 +200,121 @@ static void cs_etm_decoder__clear_buffer(struct cs_etm_decoder *decoder)
>  	}
>  }
>  
> +static ocsd_datapath_resp_t
> +cs_etm_decoder__buffer_packet(struct cs_etm_decoder *decoder,
> +			      const ocsd_generic_trace_elem *elem,
> +			      const u8 trace_chan_id,
> +			      enum cs_etm_sample_type sample_type)
> +{
> +	u32 et = 0;
> +	struct int_node *inode = NULL;
> +
> +	if (decoder->packet_count >= MAX_BUFFER - 1)
> +		return OCSD_RESP_FATAL_SYS_ERR;
> +
> +	/* Search the RB tree for the cpu associated with this traceID */
> +	inode = intlist__find(traceid_list, trace_chan_id);
> +	if (!inode)
> +		return OCSD_RESP_FATAL_SYS_ERR;
> +
> +	et = decoder->tail;
> +	decoder->packet_buffer[et].sample_type = sample_type;
> +	decoder->packet_buffer[et].start_addr = elem->st_addr;
> +	decoder->packet_buffer[et].end_addr = elem->en_addr;
> +	decoder->packet_buffer[et].exc = false;
> +	decoder->packet_buffer[et].exc_ret = false;
> +	decoder->packet_buffer[et].cpu = *((int *)inode->priv);
> +
> +	/* Wrap around if need be */
> +	et = (et + 1) & (MAX_BUFFER - 1);
> +
> +	decoder->tail = et;
> +	decoder->packet_count++;
> +
> +	if (decoder->packet_count == MAX_BUFFER - 1)
> +		return OCSD_RESP_WAIT;
> +
> +	return OCSD_RESP_CONT;
> +}
> +
> +static ocsd_datapath_resp_t cs_etm_decoder__gen_trace_elem_printer(
> +				const void *context,
> +				const ocsd_trc_index_t indx __maybe_unused,
> +				const u8 trace_chan_id __maybe_unused,
> +				const ocsd_generic_trace_elem *elem)
> +{
> +	ocsd_datapath_resp_t resp = OCSD_RESP_CONT;
> +	struct cs_etm_decoder *decoder = (struct cs_etm_decoder *) context;

After apply this patch set and build 'perf' tool with linking
OpenCSDv0.8.0 libs, I can everytime OpenCSD parses 'elem->elem_type'
is OCSD_GEN_TRC_ELEM_ADDR_NACC but not OCSD_GEN_TRC_ELEM_INSTR_RANGE.

As result, the 'perf' tool can dump the raw data with '-D' option but
it cannot analyze the symbol and symbol offset with below command:

./perf script -v -a -F cpu,event,ip,sym,symoff -i ./perf.data -k vmlinux
--kallsyms ./System.map

Have uploaded perf.data/vmlinux/System.map in the folder:
http://people.linaro.org/~leo.yan/binaries/perf_4.15_r4/

Thanks,
Leo Yan

> +	switch (elem->elem_type) {
> +	case OCSD_GEN_TRC_ELEM_UNKNOWN:
> +		break;
> +	case OCSD_GEN_TRC_ELEM_NO_SYNC:
> +		decoder->trace_on = false;
> +		break;
> +	case OCSD_GEN_TRC_ELEM_TRACE_ON:
> +		decoder->trace_on = true;
> +		break;
> +	case OCSD_GEN_TRC_ELEM_INSTR_RANGE:
> +		resp = cs_etm_decoder__buffer_packet(decoder, elem,
> +						     trace_chan_id,
> +						     CS_ETM_RANGE);
> +		break;
> +	case OCSD_GEN_TRC_ELEM_EXCEPTION:
> +		decoder->packet_buffer[decoder->tail].exc = true;
> +		break;
> +	case OCSD_GEN_TRC_ELEM_EXCEPTION_RET:
> +		decoder->packet_buffer[decoder->tail].exc_ret = true;
> +		break;
> +	case OCSD_GEN_TRC_ELEM_PE_CONTEXT:
> +	case OCSD_GEN_TRC_ELEM_EO_TRACE:
> +	case OCSD_GEN_TRC_ELEM_ADDR_NACC:
> +	case OCSD_GEN_TRC_ELEM_TIMESTAMP:
> +	case OCSD_GEN_TRC_ELEM_CYCLE_COUNT:
> +	case OCSD_GEN_TRC_ELEM_ADDR_UNKNOWN:
> +	case OCSD_GEN_TRC_ELEM_EVENT:
> +	case OCSD_GEN_TRC_ELEM_SWTRACE:
> +	case OCSD_GEN_TRC_ELEM_CUSTOM:
> +	default:
> +		break;
> +	}
> +
> +	return resp;
> +}
> +
> +static int cs_etm_decoder__create_etm_packet_decoder(
> +					struct cs_etm_trace_params *t_params,
> +					struct cs_etm_decoder *decoder)
> +{
> +	const char *decoder_name;
> +	ocsd_etmv4_cfg trace_config_etmv4;
> +	void *trace_config;
> +	u8 csid;
> +
> +	switch (t_params->protocol) {
> +	case CS_ETM_PROTO_ETMV4i:
> +		cs_etm_decoder__gen_etmv4_config(t_params, &trace_config_etmv4);
> +		decoder_name = OCSD_BUILTIN_DCD_ETMV4I;
> +		trace_config = &trace_config_etmv4;
> +		break;
> +	default:
> +		return -1;
> +	}
> +
> +	if (ocsd_dt_create_decoder(decoder->dcd_tree,
> +				     decoder_name,
> +				     OCSD_CREATE_FLG_FULL_DECODER,
> +				     trace_config, &csid))
> +		return -1;
> +
> +	if (ocsd_dt_set_gen_elem_outfn(decoder->dcd_tree,
> +				       cs_etm_decoder__gen_trace_elem_printer,
> +				       decoder))
> +		return -1;
> +
> +	return 0;
> +}
> +
>  static int
>  cs_etm_decoder__create_etm_decoder(struct cs_etm_decoder_params *d_params,
>  				   struct cs_etm_trace_params *t_params,
> @@ -208,6 +323,10 @@ cs_etm_decoder__create_etm_decoder(struct cs_etm_decoder_params *d_params,
>  	if (d_params->operation == CS_ETM_OPERATION_PRINT)
>  		return cs_etm_decoder__create_etm_packet_printer(t_params,
>  								 decoder);
> +	else if (d_params->operation == CS_ETM_OPERATION_DECODE)
> +		return cs_etm_decoder__create_etm_packet_decoder(t_params,
> +								 decoder);
> +
>  	return -1;
>  }
>  
> -- 
> 2.7.4
>