[PATCH 15/26] perf inject: Cut AUX area samples

From: Arnaldo Carvalho de Melo
Date: Fri Nov 22 2019 - 09:58:07 EST


From: Adrian Hunter <adrian.hunter@xxxxxxxxx>

After decoding AUX area samples, the AUX area data is no longer needed
(having been replaced by synthesized events) so cut it out.

Signed-off-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Link: http://lore.kernel.org/lkml/20191115124225.5247-9-adrian.hunter@xxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
tools/perf/builtin-inject.c | 29 +++++++++++++++++++++++++++++
1 file changed, 29 insertions(+)

diff --git a/tools/perf/builtin-inject.c b/tools/perf/builtin-inject.c
index 1e5d28311e14..9664a72a089d 100644
--- a/tools/perf/builtin-inject.c
+++ b/tools/perf/builtin-inject.c
@@ -45,6 +45,7 @@ struct perf_inject {
u64 aux_id;
struct list_head samples;
struct itrace_synth_opts itrace_synth_opts;
+ char event_copy[PERF_SAMPLE_MAX_SIZE];
};

struct event_entry {
@@ -214,6 +215,28 @@ static int perf_event__drop_aux(struct perf_tool *tool,
return 0;
}

+static union perf_event *
+perf_inject__cut_auxtrace_sample(struct perf_inject *inject,
+ union perf_event *event,
+ struct perf_sample *sample)
+{
+ size_t sz1 = sample->aux_sample.data - (void *)event;
+ size_t sz2 = event->header.size - sample->aux_sample.size - sz1;
+ union perf_event *ev = (union perf_event *)inject->event_copy;
+
+ if (sz1 > event->header.size || sz2 > event->header.size ||
+ sz1 + sz2 > event->header.size ||
+ sz1 < sizeof(struct perf_event_header) + sizeof(u64))
+ return event;
+
+ memcpy(ev, event, sz1);
+ memcpy((void *)ev + sz1, (void *)event + event->header.size - sz2, sz2);
+ ev->header.size = sz1 + sz2;
+ ((u64 *)((void *)ev + sz1))[-1] = 0;
+
+ return ev;
+}
+
typedef int (*inject_handler)(struct perf_tool *tool,
union perf_event *event,
struct perf_sample *sample,
@@ -226,6 +249,9 @@ static int perf_event__repipe_sample(struct perf_tool *tool,
struct evsel *evsel,
struct machine *machine)
{
+ struct perf_inject *inject = container_of(tool, struct perf_inject,
+ tool);
+
if (evsel && evsel->handler) {
inject_handler f = evsel->handler;
return f(tool, event, sample, evsel, machine);
@@ -233,6 +259,9 @@ static int perf_event__repipe_sample(struct perf_tool *tool,

build_id__mark_dso_hit(tool, event, sample, evsel, machine);

+ if (inject->itrace_synth_opts.set && sample->aux_sample.size)
+ event = perf_inject__cut_auxtrace_sample(inject, event, sample);
+
return perf_event__repipe_synth(tool, event);
}

--
2.21.0