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

From: Mathieu Poirier
Date: Mon Jul 19 2021 - 16:27:16 EST


On Tue, Jul 13, 2021 at 04:40:06PM +0100, James Clark wrote:
> 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.
>
> Signed-off-by: James Clark <james.clark@xxxxxxx>
> ---
> tools/perf/util/cs-etm-decoder/cs-etm-decoder.c | 10 +++++++---
> 1 file changed, 7 insertions(+), 3 deletions(-)
>

Reviewed-by: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>

> 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
>