bpf: Add dispatchers to kallsyms

Adding dispatchers to kallsyms. It's displayed as
  bpf_dispatcher_<NAME>

where NAME is the name of dispatcher.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200312195610.346362-12-jolsa@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index 083860b..86cacb5 100644 (file)
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -531,6 +531,7 @@ struct bpf_dispatcher {
        int num_progs;
        void *image;
        u32 image_off;
+       struct bpf_ksym ksym;
 };
 
 static __always_inline unsigned int bpf_dispatcher_nop_func(
@@ -546,13 +547,17 @@ struct bpf_trampoline *bpf_trampoline_lookup(u64 key);
 int bpf_trampoline_link_prog(struct bpf_prog *prog);
 int bpf_trampoline_unlink_prog(struct bpf_prog *prog);
 void bpf_trampoline_put(struct bpf_trampoline *tr);
-#define BPF_DISPATCHER_INIT(name) {                    \
-       .mutex = __MUTEX_INITIALIZER(name.mutex),       \
-       .func = &name##_func,                           \
-       .progs = {},                                    \
-       .num_progs = 0,                                 \
-       .image = NULL,                                  \
-       .image_off = 0                                  \
+#define BPF_DISPATCHER_INIT(_name) {                           \
+       .mutex = __MUTEX_INITIALIZER(_name.mutex),              \
+       .func = &_name##_func,                                  \
+       .progs = {},                                            \
+       .num_progs = 0,                                         \
+       .image = NULL,                                          \
+       .image_off = 0,                                         \
+       .ksym = {                                               \
+               .name  = #_name,                                \
+               .lnode = LIST_HEAD_INIT(_name.ksym.lnode),      \
+       },                                                      \
 }
 
 #define DEFINE_BPF_DISPATCHER(name)                                    \

diff --git a/kernel/bpf/dispatcher.c b/kernel/bpf/dispatcher.c
index b3e5b21..a2679ba 100644 (file)
--- a/kernel/bpf/dispatcher.c
+++ b/kernel/bpf/dispatcher.c
@@ -143,6 +143,7 @@ void bpf_dispatcher_change_prog(struct bpf_dispatcher *d, struct bpf_prog *from,
                d->image = bpf_image_alloc();
                if (!d->image)
                        goto out;
+               bpf_image_ksym_add(d->image, &d->ksym);
        }
 
        prev_num_progs = d->num_progs;