perf cs-etm: Modularize auxtrace_buffer fetch function

Making the auxtrace_buffer fetch function modular so that it can be
called from different decoding context (timeless vs. non-timeless),
avoiding to repeat code.

No change in functionality is introduced by this patch.

Signed-off-by: Mathieu Poirier <[e-mail]>
Cc: Jiri Olsa <[e-mail]>
Cc: Leo Yan <[e-mail]>
Cc: Peter Zijlstra <[e-mail]>
Cc: Suzuki K Poulouse <[e-mail]>
Cc: [e-mail]
Link: http://lkml.kernel.org/r/[e-mail]
Signed-off-by: Arnaldo Carvalho de Melo <[e-mail]>

tools/perf/util/cs-etm.c

···
 
 	return 0;
 }
+/*
+ * cs_etm__get_data_block: Fetch a block from the auxtrace_buffer queue
+ *			   if need be.
+ * Returns:	< 0	if error
+ *		= 0	if no more auxtrace_buffer to read
+ *		> 0	if the current buffer isn't empty yet
+ */
+static int cs_etm__get_data_block(struct cs_etm_queue *etmq)
+{
+	int ret;
+
+	if (!etmq->buf_len) {
+		ret = cs_etm__get_trace(etmq);
+		if (ret <= 0)
+			return ret;
+		/*
+		 * We cannot assume consecutive blocks in the data file
+		 * are contiguous, reset the decoder to force re-sync.
+		 */
+		ret = cs_etm_decoder__reset(etmq->decoder);
+		if (ret)
+			return ret;
+	}
+
+	return etmq->buf_len;
+}
 
 static bool cs_etm__is_svc_instr(struct cs_etm_queue *etmq,
 				 struct cs_etm_packet *packet,
···
 
 	/* Go through each buffer in the queue and decode them one by one */
 	while (1) {
-		if (!etmq->buf_len) {
-			err = cs_etm__get_trace(etmq);
-			if (err <= 0)
-				return err;
-			/*
-			 * We cannot assume consecutive blocks in the data file
-			 * are contiguous, reset the decoder to force re-sync.
-			 */
-			err = cs_etm_decoder__reset(etmq->decoder);
-			if (err != 0)
-				return err;
-		}
+		err = cs_etm__get_data_block(etmq);
+		if (err <= 0)
+			return err;
 
 		/* Run trace decoder until buffer consumed or end of trace */
 		do {