perf intel-pt: Decoder to output CBR changes immediately (abe5a1d3) · Commits · 戴 / test

The core-to-bus ratio (CBR) provides the CPU frequency. With branches enabled, the decoder was outputting CBR changes only when there was a branch. That loses the correct time of the change if the trace is not in context (e.g. not tracing kernel space). Change to output the CBR change immediately. Signed-off-by:

Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Link: http://lkml.kernel.org/r/20190622093248.581-2-adrian.hunter@intel.com Signed-off-by:

Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/util/intel-pt-decoder/intel-pt-decoder.c

+6 −10

Original line number	Diff line number	Diff line
		@@ -2015,16 +2015,8 @@ next:

		case INTEL_PT_CBR:
		intel_pt_calc_cbr(decoder);
		if (!decoder->branch_enable &&
		decoder->cbr != decoder->cbr_seen) {
		decoder->cbr_seen = decoder->cbr;
		decoder->state.type = INTEL_PT_CBR_CHG;
		decoder->state.from_ip = decoder->ip;
		decoder->state.to_ip = 0;
		decoder->state.cbr_payload =
		decoder->packet.payload;
		if (decoder->cbr != decoder->cbr_seen)
		return 0;
		}
		break;

		case INTEL_PT_MODE_EXEC:
		@@ -2626,8 +2618,12 @@ const struct intel_pt_state intel_pt_decode(struct intel_pt_decoder decoder)
		decoder->sample_tot_cyc_cnt = decoder->tot_cyc_cnt;
		} else {
		decoder->state.err = 0;
		if (decoder->cbr != decoder->cbr_seen && decoder->state.type) {
		if (decoder->cbr != decoder->cbr_seen) {
		decoder->cbr_seen = decoder->cbr;
		if (!decoder->state.type) {
		decoder->state.from_ip = decoder->ip;
		decoder->state.to_ip = 0;
		}
		decoder->state.type \|= INTEL_PT_CBR_CHG;
		decoder->state.cbr_payload = decoder->cbr_payload;
		}

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