btf contains information necessary to annotate bpf programs. This patch
saves btf for bpf programs loaded in the system.
Signed-off-by: Song Liu <songliubrav...@fb.com>
---
tools/perf/util/bpf-event.c | 24 ++++++++++++++
tools/perf/util/bpf-event.h | 7 ++++
tools/perf/util/env.c | 65 +++++++++++++++++++++++++++++++++++++
tools/perf/util/env.h | 4 +++
4 files changed, 100 insertions(+)
diff --git a/tools/perf/util/bpf-event.c b/tools/perf/util/bpf-event.c
index 13313a3e6c4d..52507435c464 100644
--- a/tools/perf/util/bpf-event.c
+++ b/tools/perf/util/bpf-event.c
@@ -34,6 +34,29 @@ int machine__process_bpf_event(struct machine *machine
__maybe_unused,
return 0;
}
+static int perf_env__fetch_btf(struct perf_env *env,
+ u32 btf_id,
+ struct btf *btf)
+{
+ struct btf_node *node;
+ u32 data_size;
+ const void *data;
+
+ data = btf__get_raw_data(btf, &data_size);
+
+ node = malloc(data_size + sizeof(struct btf_node));
+
+ if (!node)
+ return -1;
+
+ node->id = btf_id;
+ node->data_size = data_size;
+ memcpy(node->data, data, data_size);
+
+ perf_env__insert_btf(env, node);
+ return 0;
+}
+
/*
* Synthesize PERF_RECORD_KSYMBOL and PERF_RECORD_BPF_EVENT for one bpf
* program. One PERF_RECORD_BPF_EVENT is generated for the program. And
@@ -113,6 +136,7 @@ static int perf_event__synthesize_one_bpf_prog(struct
perf_session *session,
goto out;
}
has_btf = true;
+ perf_env__fetch_btf(env, info->btf_id, btf);
}
/* Synthesize PERF_RECORD_KSYMBOL */
diff --git a/tools/perf/util/bpf-event.h b/tools/perf/util/bpf-event.h
index fad932f7404f..b9ec394dc7c7 100644
--- a/tools/perf/util/bpf-event.h
+++ b/tools/perf/util/bpf-event.h
@@ -16,6 +16,13 @@ struct bpf_prog_info_node {
struct rb_node rb_node;
};
+struct btf_node {
+ struct rb_node rb_node;
+ u32 id;
+ u32 data_size;
+ char data[];
+};
+
#ifdef HAVE_LIBBPF_SUPPORT
int machine__process_bpf_event(struct machine *machine, union perf_event
*event,
struct perf_sample *sample);
diff --git a/tools/perf/util/env.c b/tools/perf/util/env.c
index 026ca2182d50..f5556d2f4063 100644
--- a/tools/perf/util/env.c
+++ b/tools/perf/util/env.c
@@ -63,6 +63,57 @@ struct bpf_prog_info_node
*perf_env__find_bpf_prog_info(struct perf_env *env,
return node;
}
+void perf_env__insert_btf(struct perf_env *env, struct btf_node *btf_node)
+{
+ struct rb_node *parent = NULL;
+ __u32 btf_id = btf_node->id;
+ struct btf_node *node;
+ struct rb_node **p;
+
+ down_write(&env->bpf_progs.bpf_info_lock);
+ p = &env->bpf_progs.btfs.rb_node;
+
+ while (*p != NULL) {
+ parent = *p;
+ node = rb_entry(parent, struct btf_node, rb_node);
+ if (btf_id < node->id) {
+ p = &(*p)->rb_left;
+ } else if (btf_id > node->id) {
+ p = &(*p)->rb_right;
+ } else {
+ pr_debug("duplicated btf %u\n", btf_id);
+ goto out;
+ }
+ }
+
+ rb_link_node(&btf_node->rb_node, parent, p);
+ rb_insert_color(&btf_node->rb_node, &env->bpf_progs.btfs);
+out:
+ up_write(&env->bpf_progs.bpf_info_lock);
+}
+
+struct btf_node *perf_env__find_btf(struct perf_env *env, __u32 btf_id)
+{
+ struct btf_node *node = NULL;
+ struct rb_node *n;
+
+ down_read(&env->bpf_progs.bpf_info_lock);
+ n = env->bpf_progs.btfs.rb_node;
+
+ while (n) {
+ node = rb_entry(n, struct btf_node, rb_node);
+ if (btf_id < node->id)
+ n = n->rb_left;
+ else if (btf_id > node->id)
+ n = n->rb_right;
+ else
+ break;
+ }
+
+ up_read(&env->bpf_progs.bpf_info_lock);
+ return node;
+}
+
/* purge data in bpf_prog_infos tree */
static void perf_env__purge_bpf(struct perf_env *env)
{
@@ -82,6 +133,19 @@ static void perf_env__purge_bpf(struct perf_env *env)
rb_erase_init(&node->rb_node, root);
free(node);
}
+
+ root = &env->bpf_progs.btfs;
+ next = rb_first(root);
+
+ while (next) {
+ struct btf_node *node;
+
+ node = rb_entry(next, struct btf_node, rb_node);
+ next = rb_next(&node->rb_node);
+ rb_erase_init(&node->rb_node, root);
+ free(node);
+ }
+
up_write(&env->bpf_progs.bpf_info_lock);
}
@@ -119,6 +183,7 @@ void perf_env__exit(struct perf_env *env)
static void init_bpf_rb_trees(struct perf_env *env)
{
env->bpf_progs.bpf_prog_infos = RB_ROOT;
+ env->bpf_progs.btfs = RB_ROOT;
init_rwsem(&env->bpf_progs.bpf_info_lock);
}
diff --git a/tools/perf/util/env.h b/tools/perf/util/env.h
index d0c53fe6d431..b3ce7813b1a0 100644
--- a/tools/perf/util/env.h
+++ b/tools/perf/util/env.h
@@ -74,10 +74,12 @@ struct perf_env {
struct {
struct rw_semaphore bpf_info_lock;
struct rb_root bpf_prog_infos;
+ struct rb_root btfs;
} bpf_progs;
};
struct bpf_prog_info_node;
+struct btf_node;
extern struct perf_env perf_env;
@@ -97,4 +99,6 @@ void perf_env__insert_bpf_prog_info(struct perf_env *env,
struct bpf_prog_info_node *info_node);
struct bpf_prog_info_node *perf_env__find_bpf_prog_info(struct perf_env *env,
__u32 prog_id);
+void perf_env__insert_btf(struct perf_env *env, struct btf_node *btf_node);
+struct btf_node *perf_env__find_btf(struct perf_env *env, __u32 btf_id);
#endif /* __PERF_ENV_H */
--
2.17.1
