perf record: Always record id index

In preparation for recording sideband events in a virtual machine guest so
that they can be injected into a host perf.data file.

Adjust the logic so that if there are IDs then the id index is recorded.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20220610113316.6682-3-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index 3959a1b..00c2a6c 100644 (file)
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -1834,13 +1834,11 @@ static int record__synthesize(struct record *rec, bool tail)
                goto out;
 
        /* Synthesize id_index before auxtrace_info */
-       if (rec->opts.auxtrace_sample_mode || rec->opts.full_auxtrace) {
-               err = perf_event__synthesize_id_index(tool,
-                                                     process_synthesized_event,
-                                                     session->evlist, machine);
-               if (err)
-                       goto out;
-       }
+       err = perf_event__synthesize_id_index(tool,
+                                             process_synthesized_event,
+                                             session->evlist, machine);
+       if (err)
+               goto out;
 
        if (rec->opts.full_auxtrace) {
                err = perf_event__synthesize_auxtrace_info(rec->itr, tool,

diff --git a/tools/perf/util/synthetic-events.c b/tools/perf/util/synthetic-events.c
index 27acdc5..d750744 100644 (file)
--- a/tools/perf/util/synthetic-events.c
+++ b/tools/perf/util/synthetic-events.c
@@ -1719,14 +1719,17 @@ int perf_event__synthesize_id_index(struct perf_tool *tool, perf_event__handler_
        size_t nr = 0, i = 0, sz, max_nr, n;
        int err;
 
-       pr_debug2("Synthesizing id index\n");
-
        max_nr = (UINT16_MAX - sizeof(struct perf_record_id_index)) /
                 sizeof(struct id_index_entry);
 
        evlist__for_each_entry(evlist, evsel)
                nr += evsel->core.ids;
 
+       if (!nr)
+               return 0;
+
+       pr_debug2("Synthesizing id index\n");
+
        n = nr > max_nr ? max_nr : nr;
        sz = sizeof(struct perf_record_id_index) + n * sizeof(struct id_index_entry);
        ev = zalloc(sz);