[PATCH] perf cs-etm: Mute enumeration value warning

[James Clark]

On 22/10/2025 3:28 pm, Leo Yan wrote:
> When the OpenCSD library introduces a new enumeration value (for example,
> in the v1.7.1 release), the perf build fails with an error:
> 
>    util/cs-etm-decoder/cs-etm-decoder.c:600:10: error: enumeration value 'OCSD_GEN_TRC_ELEM_ITMTRACE' not explicitly handled in switch [-Werror, -Wswitch-enum]
>      600 |         switch (elem->elem_type) {
> 	|                 ^~~~~~~~~~~~~~~
>    1 error generated.
> 
> Convert to if-else sentences to mute the enumeration value warning,
> which can avoid build failures whenever the lib is updated.
> 
> No functional change.
> 
> Suggested-by: Suzuki K Poulose <suzuki.poulose at arm.com>
> Signed-off-by: Leo Yan <leo.yan at arm.com>

Reviewed-by: James Clark <james.clark at linaro.org>

> ---
>   .../perf/util/cs-etm-decoder/cs-etm-decoder.c | 44 +++++--------------
>   1 file changed, 11 insertions(+), 33 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 b85a8837bddc..3050fe212666 100644
> --- a/tools/perf/util/cs-etm-decoder/cs-etm-decoder.c
> +++ b/tools/perf/util/cs-etm-decoder/cs-etm-decoder.c
> @@ -588,6 +588,7 @@ static ocsd_datapath_resp_t cs_etm_decoder__gen_trace_elem_printer(
>   				const ocsd_generic_trace_elem *elem)
>   {
>   	ocsd_datapath_resp_t resp = OCSD_RESP_CONT;
> +	ocsd_gen_trc_elem_t type;
>   	struct cs_etm_decoder *decoder = (struct cs_etm_decoder *) context;
>   	struct cs_etm_queue *etmq = decoder->data;
>   	struct cs_etm_packet_queue *packet_queue;
> @@ -597,52 +598,29 @@ static ocsd_datapath_resp_t cs_etm_decoder__gen_trace_elem_printer(
>   	if (!packet_queue)
>   		return OCSD_RESP_FATAL_SYS_ERR;
>   
> -	switch (elem->elem_type) {
> -	case OCSD_GEN_TRC_ELEM_UNKNOWN:
> -		break;
> -	case OCSD_GEN_TRC_ELEM_EO_TRACE:
> -	case OCSD_GEN_TRC_ELEM_NO_SYNC:
> -	case OCSD_GEN_TRC_ELEM_TRACE_ON:
> +	type = elem->elem_type;
> +
> +	if (type == OCSD_GEN_TRC_ELEM_EO_TRACE ||
> +	    type == OCSD_GEN_TRC_ELEM_NO_SYNC ||
> +	    type == OCSD_GEN_TRC_ELEM_TRACE_ON)
>   		resp = cs_etm_decoder__buffer_discontinuity(etmq, packet_queue,
>   							    trace_chan_id);
> -		break;
> -	case OCSD_GEN_TRC_ELEM_INSTR_RANGE:
> +	else if (type == OCSD_GEN_TRC_ELEM_INSTR_RANGE)
>   		resp = cs_etm_decoder__buffer_range(etmq, packet_queue, elem,
>   						    trace_chan_id);
> -		break;
> -	case OCSD_GEN_TRC_ELEM_EXCEPTION:
> +	else if (type == OCSD_GEN_TRC_ELEM_EXCEPTION)
>   		resp = cs_etm_decoder__buffer_exception(etmq, packet_queue, elem,
>   							trace_chan_id);
> -		break;
> -	case OCSD_GEN_TRC_ELEM_EXCEPTION_RET:
> +	else if (type == OCSD_GEN_TRC_ELEM_EXCEPTION_RET)
>   		resp = cs_etm_decoder__buffer_exception_ret(etmq, packet_queue,
>   							    trace_chan_id);
> -		break;
> -	case OCSD_GEN_TRC_ELEM_TIMESTAMP:
> +	else if (type == OCSD_GEN_TRC_ELEM_TIMESTAMP)
>   		resp = cs_etm_decoder__do_hard_timestamp(etmq, elem,
>   							 trace_chan_id,
>   							 indx);
> -		break;
> -	case OCSD_GEN_TRC_ELEM_PE_CONTEXT:
> +	else if (type == OCSD_GEN_TRC_ELEM_PE_CONTEXT)
>   		resp = cs_etm_decoder__set_tid(etmq, packet_queue,
>   					       elem, trace_chan_id);
> -		break;
> -	/* Unused packet types */
> -	case OCSD_GEN_TRC_ELEM_I_RANGE_NOPATH:
> -	case OCSD_GEN_TRC_ELEM_ADDR_NACC:
> -	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:
> -	case OCSD_GEN_TRC_ELEM_SYNC_MARKER:
> -	case OCSD_GEN_TRC_ELEM_MEMTRANS:
> -#if (OCSD_VER_NUM >= 0x010400)
> -	case OCSD_GEN_TRC_ELEM_INSTRUMENTATION:
> -#endif
> -	default:
> -		break;
> -	}
>   
>   	return resp;
>   }