[PATCH 07/15] perf tools: Store build id from mmap2 events

Jiri Olsa
2020-12-14T11:01:43Z

When processing mmap2 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>
---
tools/lib/perf/include/perf/event.h | 18 ++++++++++++++----
tools/perf/util/machine.c | 24 +++++++++++++++++++-----
tools/perf/util/map.c | 8 ++++++--
tools/perf/util/map.h | 3 ++-
4 files changed, 41 insertions(+), 12 deletions(-)

diff --git a/tools/lib/perf/include/perf/event.h b/tools/lib/perf/include/perf/event.h
index 988c539bedb6..d82054225fcc 100644
--- a/tools/lib/perf/include/perf/event.h
+++ b/tools/lib/perf/include/perf/event.h
@@ -23,10 +23,20 @@ struct perf_record_mmap2 {
__u64 start;
__u64 len;
__u64 pgoff;
- __u32 maj;
- __u32 min;
- __u64 ino;
- __u64 ino_generation;
+ 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];
diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c
index 1ae32a81639c..1edb7d10b042 100644
--- a/tools/perf/util/machine.c
+++ b/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;
diff --git a/tools/perf/util/map.c b/tools/perf/util/map.c
index f44ede437dc7..692e56dc832e 100644
--- a/tools/perf/util/map.c
+++ b/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;
diff --git a/tools/perf/util/map.h b/tools/perf/util/map.h
index b1c0686db1b7..9f32825c98d8 100644
--- a/tools/perf/util/map.h
+++ b/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);
--
2.26.2