[PATCH v7 5/8] perf tool: add print support for namespace events

[Hari Bathini <hbathini@linux.vnet.ibm.com>]

Add print support for events of type PERF_RECORD_NAMESPACES.

Signed-off-by: Hari Bathini <hbathini@linux.vnet.ibm.com>
---
 tools/perf/util/event.c   |   30 ++++++++++++++++++++++++++++++
 tools/perf/util/event.h   |    1 +
 tools/perf/util/machine.c |    3 +++
 3 files changed, 34 insertions(+)

diff --git a/tools/perf/util/event.c b/tools/perf/util/event.c
index c8c112a..43b6a8f 100644
--- a/tools/perf/util/event.c
+++ b/tools/perf/util/event.c
@@ -1104,6 +1104,33 @@ size_t perf_event__fprintf_comm(union perf_event *event, FILE *fp)
 	return fprintf(fp, "%s: %s:%d/%d\n", s, event->comm.comm, event->comm.pid, event->comm.tid);
 }
 
+size_t perf_event__fprintf_namespaces(union perf_event *event, FILE *fp)
+{
+	size_t ret = 0;
+	struct perf_ns_link_info *ns_link_info;
+	u32 nr_namespaces, idx;
+
+	ns_link_info = event->namespaces.link_info;
+	nr_namespaces = event->namespaces.nr_namespaces;
+
+	ret += fprintf(fp, " %d/%d - nr_namespaces: %u\n\t[",
+		       event->namespaces.pid,
+		       event->namespaces.tid,
+		       nr_namespaces);
+
+	for (idx = 0; idx < nr_namespaces; idx++) {
+		if (idx && (idx % 4 == 0))
+			ret += fprintf(fp, "\n\t ");
+
+		ret  += fprintf(fp, "%u/%s: %lu/0x%lx%s", idx,
+				perf_ns__name(idx), (u64)ns_link_info[idx].dev,
+				(u64)ns_link_info[idx].ino,
+				((idx + 1) != nr_namespaces) ? ", " : "]\n\n");
+	}
+
+	return ret;
+}
+
 int perf_event__process_comm(struct perf_tool *tool __maybe_unused,
 			     union perf_event *event,
 			     struct perf_sample *sample,
@@ -1300,6 +1327,9 @@ size_t perf_event__fprintf(union perf_event *event, FILE *fp)
 	case PERF_RECORD_MMAP:
 		ret += perf_event__fprintf_mmap(event, fp);
 		break;
+	case PERF_RECORD_NAMESPACES:
+		ret += perf_event__fprintf_namespaces(event, fp);
+		break;
 	case PERF_RECORD_MMAP2:
 		ret += perf_event__fprintf_mmap2(event, fp);
 		break;
diff --git a/tools/perf/util/event.h b/tools/perf/util/event.h
index c73ad47..8eb470b 100644
--- a/tools/perf/util/event.h
+++ b/tools/perf/util/event.h
@@ -673,6 +673,7 @@ size_t perf_event__fprintf_itrace_start(union perf_event *event, FILE *fp);
 size_t perf_event__fprintf_switch(union perf_event *event, FILE *fp);
 size_t perf_event__fprintf_thread_map(union perf_event *event, FILE *fp);
 size_t perf_event__fprintf_cpu_map(union perf_event *event, FILE *fp);
+size_t perf_event__fprintf_namespaces(union perf_event *event, FILE *fp);
 size_t perf_event__fprintf(union perf_event *event, FILE *fp);
 
 u64 kallsyms__get_function_start(const char *kallsyms_filename,
diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c
index 060fabb..5f46ad0 100644
--- a/tools/perf/util/machine.c
+++ b/tools/perf/util/machine.c
@@ -519,6 +519,9 @@ int machine__process_namespaces_event(struct machine *machine __maybe_unused,
 		  "\nWARNING: perf tool seems to support more namespaces than"
 		  " the kernel.\nTry updating the kernel..\n\n");
 
+	if (dump_trace)
+		perf_event__fprintf_namespaces(event, stdout);
+
 	if (thread == NULL ||
 	    thread__set_namespaces(thread, sample->time, &event->namespaces)) {
 		dump_printf("problem processing PERF_RECORD_NAMESPACES, skipping event.\n");