perf cs-etm: Don't test full_auxtrace because it's always set

There is no path in cs-etm where this isn't true so it doesn't need to
be tested. Also re-order the beginning of cs_etm_recording_options() so
that nothing is done until the early exit is passed.

Signed-off-by: James Clark <james.clark@arm.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Denis Nikitin <denik@google.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: John Garry <john.g.garry@oracle.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Yang Shi <shy828301@gmail.com>
Cc: coresight@lists.linaro.org
Cc: linux-arm-kernel@lists.infradead.org
Link: https://lore.kernel.org/r/20230424134748.228137-4-james.clark@arm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Author: James-A-Clark

tools/perf/arch/arm/util/cs-etm.c

@@ -319,32 +319,33 @@ static int cs_etm_recording_options(struct auxtrace_record *itr,
 	bool privileged = perf_event_paranoid_check(-1);
 	int err = 0;
 
-	ptr->evlist = evlist;
-	ptr->snapshot_mode = opts->auxtrace_snapshot_mode;
-
-	if (!record_opts__no_switch_events(opts) &&
-	    perf_can_record_switch_events())
-		opts->record_switch_events = true;
-
 	evlist__for_each_entry(evlist, evsel) {
 		if (evsel->core.attr.type == cs_etm_pmu->type) {
 			if (cs_etm_evsel) {
 				pr_err("There may be only one %s event\n",
 				       CORESIGHT_ETM_PMU_NAME);
 				return -EINVAL;
 			}
-			evsel->core.attr.freq = 0;
-			evsel->core.attr.sample_period = 1;
-			evsel->needs_auxtrace_mmap = true;
 			cs_etm_evsel = evsel;
-			opts->full_auxtrace = true;
 		}
 	}
 
 	/* no need to continue if at least one event of interest was found */
 	if (!cs_etm_evsel)
 		return 0;
 
+	ptr->evlist = evlist;
+	ptr->snapshot_mode = opts->auxtrace_snapshot_mode;
+
+	if (!record_opts__no_switch_events(opts) &&
+	    perf_can_record_switch_events())
+		opts->record_switch_events = true;
+
+	cs_etm_evsel->core.attr.freq = 0;
+	cs_etm_evsel->core.attr.sample_period = 1;
+	cs_etm_evsel->needs_auxtrace_mmap = true;
+	opts->full_auxtrace = true;
+
 	ret = cs_etm_set_sink_attr(cs_etm_pmu, cs_etm_evsel);
 	if (ret)
 		return ret;
@@ -414,16 +415,15 @@ static int cs_etm_recording_options(struct auxtrace_record *itr,
 		}
 	}
 
-	/* We are in full trace mode but '-m,xyz' wasn't specified */
-	if (opts->full_auxtrace && !opts->auxtrace_mmap_pages) {
+	/* Buffer sizes weren't specified with '-m,xyz' so give some defaults */
+	if (!opts->auxtrace_mmap_pages) {
 		if (privileged) {
 			opts->auxtrace_mmap_pages = MiB(4) / page_size;
 		} else {
 			opts->auxtrace_mmap_pages = KiB(128) / page_size;
 			if (opts->mmap_pages == UINT_MAX)
 				opts->mmap_pages = KiB(256) / page_size;
 		}
-
 	}
 
 	if (opts->auxtrace_snapshot_mode)
@@ -454,23 +454,17 @@ static int cs_etm_recording_options(struct auxtrace_record *itr,
 	}
 
 	/* Add dummy event to keep tracking */
-	if (opts->full_auxtrace) {
-		struct evsel *tracking_evsel;
-
-		err = parse_event(evlist, "dummy:u");
-		if (err)
-			goto out;
-
-		tracking_evsel = evlist__last(evlist);
-		evlist__set_tracking_event(evlist, tracking_evsel);
-
-		tracking_evsel->core.attr.freq = 0;
-		tracking_evsel->core.attr.sample_period = 1;
-
-		/* In per-cpu case, always need the time of mmap events etc */
-		if (!perf_cpu_map__empty(cpus))
-			evsel__set_sample_bit(tracking_evsel, TIME);
-	}
+	err = parse_event(evlist, "dummy:u");
+	if (err)
+		goto out;
+	evsel = evlist__last(evlist);
+	evlist__set_tracking_event(evlist, evsel);
+	evsel->core.attr.freq = 0;
+	evsel->core.attr.sample_period = 1;
+
+	/* In per-cpu case, always need the time of mmap events etc */
+	if (!perf_cpu_map__empty(cpus))
+		evsel__set_sample_bit(evsel, TIME);
 
 out:
 	return err;