[PATCH v2 4/6] perf cs-etm: Suppress printing when resetting decoder

James Clark james.clark at arm.com
Wed Jul 21 08:02:00 PDT 2021


The decoder is quite noisy when being reset. In a future commit,
dump-raw-trace will use a code path that resets the decoder rather than
creating a new one, so printing has to be suppressed to not flood the
output.

Reviewed-by: Mathieu Poirier <mathieu.poirier at linaro.org>
Signed-off-by: James Clark <james.clark at arm.com>
---
 tools/perf/util/cs-etm-decoder/cs-etm-decoder.c | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

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 3e1a05bc82cc..ed1f0326f859 100644
--- a/tools/perf/util/cs-etm-decoder/cs-etm-decoder.c
+++ b/tools/perf/util/cs-etm-decoder/cs-etm-decoder.c
@@ -35,6 +35,7 @@
 struct cs_etm_decoder {
 	void *data;
 	void (*packet_printer)(const char *msg);
+	bool suppress_printing;
 	dcd_tree_handle_t dcd_tree;
 	cs_etm_mem_cb_type mem_access;
 	ocsd_datapath_resp_t prev_return;
@@ -74,9 +75,10 @@ int cs_etm_decoder__reset(struct cs_etm_decoder *decoder)
 	ocsd_datapath_resp_t dp_ret;
 
 	decoder->prev_return = OCSD_RESP_CONT;
-
+	decoder->suppress_printing = true;
 	dp_ret = ocsd_dt_process_data(decoder->dcd_tree, OCSD_OP_RESET,
 				      0, 0, NULL, NULL);
+	decoder->suppress_printing = false;
 	if (OCSD_DATA_RESP_IS_FATAL(dp_ret))
 		return -1;
 
@@ -146,8 +148,10 @@ static void cs_etm_decoder__print_str_cb(const void *p_context,
 					 const char *msg,
 					 const int str_len)
 {
-	if (p_context && str_len)
-		((struct cs_etm_decoder *)p_context)->packet_printer(msg);
+	const struct cs_etm_decoder *decoder = p_context;
+
+	if (p_context && str_len && !decoder->suppress_printing)
+		decoder->packet_printer(msg);
 }
 
 static int
-- 
2.28.0




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