perf inject: Add --strip option to strip out non-synthesized events

Add a new option --strip which is used with --itrace to strip out
non-synthesized events.  This results in a perf.data file that is
simpler for external tools to parse.  In particular, this can be used to
prepare a perf.data file for consumption by autofdo.

A subsequent patch makes a change to Intel PT also to enable use with
autofdo and gives an example of that use.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/1443186956-18718-25-git-send-email-adrian.hunter@intel.com
[ Made it use perf_evlist__remove() + perf_evsel__delete() ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

diff --git a/tools/perf/Documentation/perf-inject.txt b/tools/perf/Documentation/perf-inject.txt
index 0c721c3e37e1131e3546b2c0440bbcdef289a54e..0b1cedeef895369c9c60aa0a1e6cbb718c65c509 100644 (file)
--- a/tools/perf/Documentation/perf-inject.txt
+++ b/tools/perf/Documentation/perf-inject.txt
@@ -50,6 +50,9 @@ OPTIONS
 
 include::itrace.txt[]
 
+--strip::
+       Use with --itrace to strip out non-synthesized events.
+
 SEE ALSO
 --------
 linkperf:perf-record[1], linkperf:perf-report[1], linkperf:perf-archive[1]

diff --git a/tools/perf/builtin-inject.c b/tools/perf/builtin-inject.c
index 9b6119f134b4f365aba31bc6ab66b7f4fb3f7528..0a945d2e8ca5b1bd319fa18537e7a4c57e3b7291 100644 (file)
--- a/tools/perf/builtin-inject.c
+++ b/tools/perf/builtin-inject.c
@@ -28,6 +28,7 @@ struct perf_inject {
        bool                    build_ids;
        bool                    sched_stat;
        bool                    have_auxtrace;
+       bool                    strip;
        const char              *input_name;
        struct perf_data_file   output;
        u64                     bytes_written;
@@ -177,6 +178,14 @@ static int perf_event__repipe(struct perf_tool *tool,
        return perf_event__repipe_synth(tool, event);
 }
 
+static int perf_event__drop(struct perf_tool *tool __maybe_unused,
+                           union perf_event *event __maybe_unused,
+                           struct perf_sample *sample __maybe_unused,
+                           struct machine *machine __maybe_unused)
+{
+       return 0;
+}
+
 static int perf_event__drop_aux(struct perf_tool *tool,
                                union perf_event *event __maybe_unused,
                                struct perf_sample *sample,
@@ -480,6 +489,78 @@ static int perf_evsel__check_stype(struct perf_evsel *evsel,
        return 0;
 }
 
+static int drop_sample(struct perf_tool *tool __maybe_unused,
+                      union perf_event *event __maybe_unused,
+                      struct perf_sample *sample __maybe_unused,
+                      struct perf_evsel *evsel __maybe_unused,
+                      struct machine *machine __maybe_unused)
+{
+       return 0;
+}
+
+static void strip_init(struct perf_inject *inject)
+{
+       struct perf_evlist *evlist = inject->session->evlist;
+       struct perf_evsel *evsel;
+
+       inject->tool.context_switch = perf_event__drop;
+
+       evlist__for_each(evlist, evsel)
+               evsel->handler = drop_sample;
+}
+
+static bool has_tracking(struct perf_evsel *evsel)
+{
+       return evsel->attr.mmap || evsel->attr.mmap2 || evsel->attr.comm ||
+              evsel->attr.task;
+}
+
+#define COMPAT_MASK (PERF_SAMPLE_ID | PERF_SAMPLE_TID | PERF_SAMPLE_TIME | \
+                    PERF_SAMPLE_ID | PERF_SAMPLE_CPU | PERF_SAMPLE_IDENTIFIER)
+
+/*
+ * In order that the perf.data file is parsable, tracking events like MMAP need
+ * their selected event to exist, except if there is only 1 selected event left
+ * and it has a compatible sample type.
+ */
+static bool ok_to_remove(struct perf_evlist *evlist,
+                        struct perf_evsel *evsel_to_remove)
+{
+       struct perf_evsel *evsel;
+       int cnt = 0;
+       bool ok = false;
+
+       if (!has_tracking(evsel_to_remove))
+               return true;
+
+       evlist__for_each(evlist, evsel) {
+               if (evsel->handler != drop_sample) {
+                       cnt += 1;
+                       if ((evsel->attr.sample_type & COMPAT_MASK) ==
+                           (evsel_to_remove->attr.sample_type & COMPAT_MASK))
+                               ok = true;
+               }
+       }
+
+       return ok && cnt == 1;
+}
+
+static void strip_fini(struct perf_inject *inject)
+{
+       struct perf_evlist *evlist = inject->session->evlist;
+       struct perf_evsel *evsel, *tmp;
+
+       /* Remove non-synthesized evsels if possible */
+       evlist__for_each_safe(evlist, tmp, evsel) {
+               if (evsel->handler == drop_sample &&
+                   ok_to_remove(evlist, evsel)) {
+                       pr_debug("Deleting %s\n", perf_evsel__name(evsel));
+                       perf_evlist__remove(evlist, evsel);
+                       perf_evsel__delete(evsel);
+               }
+       }
+}
+
 static int __cmd_inject(struct perf_inject *inject)
 {
        int ret = -EINVAL;
@@ -532,6 +613,8 @@ static int __cmd_inject(struct perf_inject *inject)
                inject->tool.ordering_requires_timestamps = true;
                /* Allow space in the header for new attributes */
                output_data_offset = 4096;
+               if (inject->strip)
+                       strip_init(inject);
        }
 
        if (!inject->itrace_synth_opts.set)
@@ -570,6 +653,8 @@ static int __cmd_inject(struct perf_inject *inject)
                                perf_evlist__remove(session->evlist, evsel);
                                perf_evsel__delete(evsel);
                        }
+                       if (inject->strip)
+                               strip_fini(inject);
                }
                session->header.data_offset = output_data_offset;
                session->header.data_size = inject->bytes_written;
@@ -635,6 +720,8 @@ int cmd_inject(int argc, const char **argv, const char *prefix __maybe_unused)
                OPT_CALLBACK_OPTARG(0, "itrace", &inject.itrace_synth_opts,
                                    NULL, "opts", "Instruction Tracing options",
                                    itrace_parse_synth_opts),
+               OPT_BOOLEAN(0, "strip", &inject.strip,
+                           "strip non-synthesized events (use with --itrace)"),
                OPT_END()
        };
        const char * const inject_usage[] = {
@@ -650,6 +737,11 @@ int cmd_inject(int argc, const char **argv, const char *prefix __maybe_unused)
        if (argc)
                usage_with_options(inject_usage, options);
 
+       if (inject.strip && !inject.itrace_synth_opts.set) {
+               pr_err("--strip option requires --itrace option\n");
+               return -1;
+       }
+
        if (perf_data_file__open(&inject.output)) {
                perror("failed to create output file");
                return -1;