[RFC PATCH v6 29/32] perf record: Load all eBPF object into kernel

Wang Nan
2015-06-09T05:53:03Z

This patch utilizes bpf_load_object() provided by libbpf to load all
objects into kernel.

Signed-off-by: Wang Nan <wangnan0@huawei.com>
---
tools/perf/builtin-record.c | 12 ++++++++++++
tools/perf/util/bpf-loader.c | 19 +++++++++++++++++++
tools/perf/util/bpf-loader.h | 2 ++
3 files changed, 33 insertions(+)

diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index a7c178e..5ce9d4a 100644
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -1121,6 +1121,18 @@ int cmd_record(int argc, const char **argv, const char *prefix __maybe_unused)
return err;
}

+ /*
+ * bpf__probe() also calls symbol__init() if there are probe
+ * events in bpf objects, so calling symbol_exit when failuer
+ * is safe. If there is no probe event, bpf__load() always
+ * success.
+ */
+ err = bpf__load();
+ if (err) {
+ pr_err("Loading BPF programs failed\n");
+ goto out_symbol_exit;
+ }
+
symbol__init(NULL);

if (symbol_conf.kptr_restrict)
diff --git a/tools/perf/util/bpf-loader.c b/tools/perf/util/bpf-loader.c
index 8c0bf46..45282e9 100644
--- a/tools/perf/util/bpf-loader.c
+++ b/tools/perf/util/bpf-loader.c
@@ -420,3 +420,22 @@ int bpf__probe(void)

return err < 0 ? err : 0;
}
+
+int bpf__load(void)
+{
+ struct bpf_object *obj, *tmp;
+ int err = 0;
+
+ bpf_object__for_each(obj, tmp) {
+ err = bpf_object__load(obj);
+ if (err) {
+ pr_err("bpf: load objects failed\n");
+ goto errout;
+ }
+ }
+ return 0;
+errout:
+ bpf_object__for_each(obj, tmp)
+ bpf_object__unload(obj);
+ return err;
+}
diff --git a/tools/perf/util/bpf-loader.h b/tools/perf/util/bpf-loader.h
index 7387fb6..e9c5f61 100644
--- a/tools/perf/util/bpf-loader.h
+++ b/tools/perf/util/bpf-loader.h
@@ -23,6 +23,7 @@ extern int perf_bpf_config(const char *var, const char *value);
int bpf__prepare_load(const char *filename, bool source);
int bpf__probe(void);
int bpf__unprobe(void);
+int bpf__load(void);

void bpf__clear(void);
#else
@@ -34,6 +35,7 @@ static inline int bpf__prepare_load(const char *filename __maybe_unused)

static inline int bpf__probe(void) { return 0; }
static inline int bpf__unprobe(void) { return 0; }
+static inline int bpf__load(void) { return 0; }
static inline void bpf__clear(void) { }
#endif
#endif
--
1.8.3.4