perf tools: Factor out evsel__id_hdr_size()

Factor out evsel__id_hdr_size() so it can be reused.

This is needed by perf inject. When injecting events from a guest perf.data
file, there is a possibility that the sample ID numbers conflict. To
re-write an ID sample, the old one needs to be removed first, which means
determining how big it is with evsel__id_hdr_size() and then subtracting
that from the event size.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: kvm@vger.kernel.org
Link: https://lore.kernel.org/r/20220711093218.10967-6-adrian.hunter@intel.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/util/evlist.c

@@ -1244,34 +1244,8 @@ bool evlist__valid_read_format(struct evlist *evlist)
 u16 evlist__id_hdr_size(struct evlist *evlist)
 {
 	struct evsel *first = evlist__first(evlist);
-	struct perf_sample *data;
-	u64 sample_type;
-	u16 size = 0;
 
-	if (!first->core.attr.sample_id_all)
-		goto out;
-
-	sample_type = first->core.attr.sample_type;
-
-	if (sample_type & PERF_SAMPLE_TID)
-		size += sizeof(data->tid) * 2;
-
-       if (sample_type & PERF_SAMPLE_TIME)
-		size += sizeof(data->time);
-
-	if (sample_type & PERF_SAMPLE_ID)
-		size += sizeof(data->id);
-
-	if (sample_type & PERF_SAMPLE_STREAM_ID)
-		size += sizeof(data->stream_id);
-
-	if (sample_type & PERF_SAMPLE_CPU)
-		size += sizeof(data->cpu) * 2;
-
-	if (sample_type & PERF_SAMPLE_IDENTIFIER)
-		size += sizeof(data->id);
-out:
-	return size;
+	return first->core.attr.sample_id_all ? evsel__id_hdr_size(first) : 0;
 }
 
 bool evlist__valid_sample_id_all(struct evlist *evlist)

tools/perf/util/evsel.c

@@ -2724,6 +2724,32 @@ int evsel__parse_sample_timestamp(struct evsel *evsel, union perf_event *event,
 	return 0;
 }
 
+u16 evsel__id_hdr_size(struct evsel *evsel)
+{
+	u64 sample_type = evsel->core.attr.sample_type;
+	u16 size = 0;
+
+	if (sample_type & PERF_SAMPLE_TID)
+		size += sizeof(u64);
+
+	if (sample_type & PERF_SAMPLE_TIME)
+		size += sizeof(u64);
+
+	if (sample_type & PERF_SAMPLE_ID)
+		size += sizeof(u64);
+
+	if (sample_type & PERF_SAMPLE_STREAM_ID)
+		size += sizeof(u64);
+
+	if (sample_type & PERF_SAMPLE_CPU)
+		size += sizeof(u64);
+
+	if (sample_type & PERF_SAMPLE_IDENTIFIER)
+		size += sizeof(u64);
+
+	return size;
+}
+
 struct tep_format_field *evsel__field(struct evsel *evsel, const char *name)
 {
 	return tep_find_field(evsel->tp_format, name);

tools/perf/util/evsel.h

@@ -381,6 +381,8 @@ int evsel__parse_sample(struct evsel *evsel, union perf_event *event,
 int evsel__parse_sample_timestamp(struct evsel *evsel, union perf_event *event,
 				  u64 *timestamp);
 
+u16 evsel__id_hdr_size(struct evsel *evsel);
+
 static inline struct evsel *evsel__next(struct evsel *evsel)
 {
 	return list_entry(evsel->core.node.next, struct evsel, core.node);