perf tools: Store build id when available in PERF_RECORD_MMAP2 metadata events

When processing a PERF_RECORD_MMAP2 metadata event, check on the build
id misc bit: PERF_RECORD_MISC_MMAP_BUILD_ID and if it is set, store the
build id in mmap's dso object.

Also adding the build id data to struct perf_record_mmap2 event
definition.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Budankov <abudankov@huawei.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <songliubraving@fb.com>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20201214105457.543111-8-jolsa@kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/lib/perf/include/perf/event.h

@@ -23,10 +23,20 @@ struct perf_record_mmap2 {
 	__u64			 start;
 	__u64			 len;
 	__u64			 pgoff;
+	union {
+		struct {
 			__u32	 maj;
 			__u32	 min;
 			__u64	 ino;
 			__u64	 ino_generation;
+		};
+		struct {
+			__u8	 build_id_size;
+			__u8	 __reserved_1;
+			__u16	 __reserved_2;
+			__u8	 build_id[20];
+		};
+	};
 	__u32			 prot;
 	__u32			 flags;
 	char			 filename[PATH_MAX];

tools/perf/util/machine.c

@@ -1599,7 +1599,8 @@ static int machine__process_extra_kernel_map(struct machine *machine,
 }
 
 static int machine__process_kernel_mmap_event(struct machine *machine,
-					      struct extra_kernel_map *xm)
+					      struct extra_kernel_map *xm,
+					      struct build_id *bid)
 {
 	struct map *map;
 	enum dso_space_type dso_space;
@@ -1624,6 +1625,10 @@ static int machine__process_kernel_mmap_event(struct machine *machine,
 			goto out_problem;
 
 		map->end = map->start + xm->end - xm->start;
+
+		if (build_id__is_defined(bid))
+			dso__set_build_id(map->dso, bid);
+
 	} else if (is_kernel_mmap) {
 		const char *symbol_name = (xm->name + strlen(machine->mmap_name));
 		/*
@@ -1681,6 +1686,9 @@ static int machine__process_kernel_mmap_event(struct machine *machine,
 
 		machine__update_kernel_mmap(machine, xm->start, xm->end);
 
+		if (build_id__is_defined(bid))
+			dso__set_build_id(kernel, bid);
+
 		/*
 		 * Avoid using a zero address (kptr_restrict) for the ref reloc
 		 * symbol. Effectively having zero here means that at record
@@ -1718,11 +1726,17 @@ int machine__process_mmap2_event(struct machine *machine,
 		.ino = event->mmap2.ino,
 		.ino_generation = event->mmap2.ino_generation,
 	};
+	struct build_id __bid, *bid = NULL;
 	int ret = 0;
 
 	if (dump_trace)
 		perf_event__fprintf_mmap2(event, stdout);
 
+	if (event->header.misc & PERF_RECORD_MISC_MMAP_BUILD_ID) {
+		bid = &__bid;
+		build_id__init(bid, event->mmap2.build_id, event->mmap2.build_id_size);
+	}
+
 	if (sample->cpumode == PERF_RECORD_MISC_GUEST_KERNEL ||
 	    sample->cpumode == PERF_RECORD_MISC_KERNEL) {
 		struct extra_kernel_map xm = {
@@ -1732,7 +1746,7 @@ int machine__process_mmap2_event(struct machine *machine,
 		};
 
 		strlcpy(xm.name, event->mmap2.filename, KMAP_NAME_LEN);
-		ret = machine__process_kernel_mmap_event(machine, &xm);
+		ret = machine__process_kernel_mmap_event(machine, &xm, bid);
 		if (ret < 0)
 			goto out_problem;
 		return 0;
@@ -1746,7 +1760,7 @@ int machine__process_mmap2_event(struct machine *machine,
 	map = map__new(machine, event->mmap2.start,
 			event->mmap2.len, event->mmap2.pgoff,
 			&dso_id, event->mmap2.prot,
-			event->mmap2.flags,
+			event->mmap2.flags, bid,
 			event->mmap2.filename, thread);
 
 	if (map == NULL)
@@ -1789,7 +1803,7 @@ int machine__process_mmap_event(struct machine *machine, union perf_event *event
 		};
 
 		strlcpy(xm.name, event->mmap.filename, KMAP_NAME_LEN);
-		ret = machine__process_kernel_mmap_event(machine, &xm);
+		ret = machine__process_kernel_mmap_event(machine, &xm, NULL);
 		if (ret < 0)
 			goto out_problem;
 		return 0;
@@ -1805,7 +1819,7 @@ int machine__process_mmap_event(struct machine *machine, union perf_event *event
 
 	map = map__new(machine, event->mmap.start,
 			event->mmap.len, event->mmap.pgoff,
-			NULL, prot, 0, event->mmap.filename, thread);
+			NULL, prot, 0, NULL, event->mmap.filename, thread);
 
 	if (map == NULL)
 		goto out_problem_map;

tools/perf/util/map.c

@@ -130,8 +130,8 @@ void map__init(struct map *map, u64 start, u64 end, u64 pgoff, struct dso *dso)
 
 struct map *map__new(struct machine *machine, u64 start, u64 len,
 		     u64 pgoff, struct dso_id *id,
-		     u32 prot, u32 flags, char *filename,
-		     struct thread *thread)
+		     u32 prot, u32 flags, struct build_id *bid,
+		     char *filename, struct thread *thread)
 {
 	struct map *map = malloc(sizeof(*map));
 	struct nsinfo *nsi = NULL;
@@ -194,6 +194,10 @@ struct map *map__new(struct machine *machine, u64 start, u64 len,
 				dso__set_loaded(dso);
 		}
 		dso->nsinfo = nsi;
+
+		if (build_id__is_defined(bid))
+			dso__set_build_id(dso, bid);
+
 		dso__put(dso);
 	}
 	return map;

tools/perf/util/map.h

@@ -104,10 +104,11 @@ void map__init(struct map *map,
 	       u64 start, u64 end, u64 pgoff, struct dso *dso);
 
 struct dso_id;
+struct build_id;
 
 struct map *map__new(struct machine *machine, u64 start, u64 len,
 		     u64 pgoff, struct dso_id *id, u32 prot, u32 flags,
-		     char *filename, struct thread *thread);
+		     struct build_id *bid, char *filename, struct thread *thread);
 struct map *map__new2(u64 start, struct dso *dso);
 void map__delete(struct map *map);
 struct map *map__clone(struct map *map);