perf tools: Remove special handling of system-wide evsel

For system-wide evsels, the thread map should be dummy - i.e. it has a
single entry of -1.  But the code guarantees such a thread map, so no
need to handle it specially.

No functional change intended.
Reviewed-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20221003204647.1481128-6-namhyung@kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/lib/perf/evsel.c

@@ -515,9 +515,6 @@ int perf_evsel__alloc_id(struct perf_evsel *evsel, int ncpus, int nthreads)
 	if (ncpus == 0 || nthreads == 0)
 		return 0;
 
-	if (evsel->system_wide)
-		nthreads = 1;
-
 	evsel->sample_id = xyarray__new(ncpus, nthreads, sizeof(struct perf_sample_id));
 	if (evsel->sample_id == NULL)
 		return -ENOMEM;

tools/perf/builtin-script.c

@@ -2243,9 +2243,6 @@ static void __process_stat(struct evsel *counter, u64 tstamp)
 	struct perf_cpu cpu;
 	static int header_printed;
 
-	if (counter->core.system_wide)
-		nthreads = 1;
-
 	if (!header_printed) {
 		printf("%3s %8s %15s %15s %15s %15s %s\n",
 		       "CPU", "THREAD", "VAL", "ENA", "RUN", "TIME", "EVENT");

tools/perf/util/evsel.c

@@ -1813,7 +1813,7 @@ static struct perf_thread_map *empty_thread_map;
 static int __evsel__prepare_open(struct evsel *evsel, struct perf_cpu_map *cpus,
 		struct perf_thread_map *threads)
 {
-	int nthreads;
+	int nthreads = perf_thread_map__nr(threads);
 
 	if ((perf_missing_features.write_backward && evsel->core.attr.write_backward) ||
 	    (perf_missing_features.aux_output     && evsel->core.attr.aux_output))
@@ -1839,11 +1839,6 @@ static int __evsel__prepare_open(struct evsel *evsel, struct perf_cpu_map *cpus,
 		threads = empty_thread_map;
 	}
 
-	if (evsel->core.system_wide)
-		nthreads = 1;
-	else
-		nthreads = threads->nr;
-
 	if (evsel->core.fd == NULL &&
 	    perf_evsel__alloc_fd(&evsel->core, perf_cpu_map__nr(cpus), nthreads) < 0)
 		return -ENOMEM;
@@ -2061,10 +2056,7 @@ static int evsel__open_cpu(struct evsel *evsel, struct perf_cpu_map *cpus,
 	if (threads == NULL)
 		threads = empty_thread_map;
 
-	if (evsel->core.system_wide)
-		nthreads = 1;
-	else
-		nthreads = threads->nr;
+	nthreads = perf_thread_map__nr(threads);
 
 	if (evsel->cgrp)
 		pid = evsel->cgrp->fd;

tools/perf/util/stat.c

@@ -420,9 +420,6 @@ static int process_counter_maps(struct perf_stat_config *config,
 	int ncpus = evsel__nr_cpus(counter);
 	int idx, thread;
 
-	if (counter->core.system_wide)
-		nthreads = 1;
-
 	for (thread = 0; thread < nthreads; thread++) {
 		for (idx = 0; idx < ncpus; idx++) {
 			if (process_counter_values(config, counter, idx, thread,