perf cs-etm: Linking PE contextID with perf thread mechanic

Link contextID packets received from the decoder with the perf tool
thread mechanic so that we know the specifics of the process currently
executing.
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Tested-by: Leo Yan <leo.yan@linaro.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: coresight@lists.linaro.org
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/20190524173508.29044-16-mathieu.poirier@linaro.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/util/cs-etm-decoder/cs-etm-decoder.c

@@ -402,6 +402,24 @@ cs_etm_decoder__buffer_exception_ret(struct cs_etm_packet_queue *queue,
 					     CS_ETM_EXCEPTION_RET);
 }
 
+static ocsd_datapath_resp_t
+cs_etm_decoder__set_tid(struct cs_etm_queue *etmq,
+			const ocsd_generic_trace_elem *elem,
+			const uint8_t trace_chan_id)
+{
+	pid_t tid;
+
+	/* Ignore PE_CONTEXT packets that don't have a valid contextID */
+	if (!elem->context.ctxt_id_valid)
+		return OCSD_RESP_CONT;
+
+	tid =  elem->context.context_id;
+	if (cs_etm__etmq_set_tid(etmq, tid, trace_chan_id))
+		return OCSD_RESP_FATAL_SYS_ERR;
+
+	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,
@@ -440,6 +458,8 @@ static ocsd_datapath_resp_t cs_etm_decoder__gen_trace_elem_printer(
 							    trace_chan_id);
 		break;
 	case OCSD_GEN_TRC_ELEM_PE_CONTEXT:
+		resp = cs_etm_decoder__set_tid(etmq, elem, trace_chan_id);
+		break;
 	case OCSD_GEN_TRC_ELEM_ADDR_NACC:
 	case OCSD_GEN_TRC_ELEM_TIMESTAMP:
 	case OCSD_GEN_TRC_ELEM_CYCLE_COUNT:

tools/perf/util/cs-etm.c

@@ -907,13 +907,8 @@ cs_etm__get_trace(struct cs_etm_queue *etmq)
 }
 
 static void cs_etm__set_pid_tid_cpu(struct cs_etm_auxtrace *etm,
-				    struct auxtrace_queue *queue,
 				    struct cs_etm_traceid_queue *tidq)
 {
-	/* CPU-wide tracing isn't supported yet */
-	if (queue->tid == -1)
-		return;
-
 	if ((!tidq->thread) && (tidq->tid != -1))
 		tidq->thread = machine__find_thread(etm->machine, -1,
 						    tidq->tid);
@@ -922,6 +917,31 @@ static void cs_etm__set_pid_tid_cpu(struct cs_etm_auxtrace *etm,
 		tidq->pid = tidq->thread->pid_;
 }
 
+int cs_etm__etmq_set_tid(struct cs_etm_queue *etmq,
+			 pid_t tid, u8 trace_chan_id)
+{
+	int cpu, err = -EINVAL;
+	struct cs_etm_auxtrace *etm = etmq->etm;
+	struct cs_etm_traceid_queue *tidq;
+
+	tidq = cs_etm__etmq_get_traceid_queue(etmq, trace_chan_id);
+	if (!tidq)
+		return err;
+
+	if (cs_etm__get_cpu(trace_chan_id, &cpu) < 0)
+		return err;
+
+	err = machine__set_current_tid(etm->machine, cpu, tid, tid);
+	if (err)
+		return err;
+
+	tidq->tid = tid;
+	thread__zput(tidq->thread);
+
+	cs_etm__set_pid_tid_cpu(etm, tidq);
+	return 0;
+}
+
 static int cs_etm__synth_instruction_sample(struct cs_etm_queue *etmq,
 					    struct cs_etm_traceid_queue *tidq,
 					    u64 addr, u64 period)
@@ -1866,7 +1886,7 @@ static int cs_etm__process_timeless_queues(struct cs_etm_auxtrace *etm,
 			continue;
 
 		if ((tid == -1) || (tidq->tid == tid)) {
-			cs_etm__set_pid_tid_cpu(etm, queue, tidq);
+			cs_etm__set_pid_tid_cpu(etm, tidq);
 			cs_etm__run_decoder(etmq);
 		}
 	}

tools/perf/util/cs-etm.h

@@ -181,6 +181,8 @@ struct cs_etm_packet_queue {
 int cs_etm__process_auxtrace_info(union perf_event *event,
 				  struct perf_session *session);
 int cs_etm__get_cpu(u8 trace_chan_id, int *cpu);
+int cs_etm__etmq_set_tid(struct cs_etm_queue *etmq,
+			 pid_t tid, u8 trace_chan_id);
 struct cs_etm_packet_queue
 *cs_etm__etmq_get_packet_queue(struct cs_etm_queue *etmq, u8 trace_chan_id);
 #else
@@ -197,6 +199,14 @@ static inline int cs_etm__get_cpu(u8 trace_chan_id __maybe_unused,
 	return -1;
 }
 
+static inline int cs_etm__etmq_set_tid(
+				struct cs_etm_queue *etmq __maybe_unused,
+				pid_t tid __maybe_unused,
+				u8 trace_chan_id __maybe_unused)
+{
+	return -1;
+}
+
 static inline struct cs_etm_packet_queue *cs_etm__etmq_get_packet_queue(
 				struct cs_etm_queue *etmq __maybe_unused,
 				u8 trace_chan_id __maybe_unused)