[PATCH v3 05/10] perf tools: Add support for decoding CoreSight trace data

From: Mathieu Poirier
Date: Wed Jan 17 2018 - 12:54:29 EST


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;
+
+ 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