On 8/20/20 11:33 PM, Andrii Nakryiko wrote:
On Thu, Aug 20, 2020 at 3:50 PM Yonghong Song <yhs@xxxxxx> wrote:
For bpf_map_elem and bpf_sk_local_storage bpf iterators,
additional map_id should be shown for fdinfo and
userspace query. For example, the following is for
a bpf_map_elem iterator.
$ cat /proc/1753/fdinfo/9
pos: 0
flags: 02000000
mnt_id: 14
link_type: iter
link_id: 34
prog_tag: 104be6d3fe45e6aa
prog_id: 173
target_name: bpf_map_elem
map_id: 127
Signed-off-by: Yonghong Song <yhs@xxxxxx>
---
include/linux/bpf.h | 4 ++++
kernel/bpf/map_iter.c | 15 +++++++++++++++
net/core/bpf_sk_storage.c | 2 ++
3 files changed, 21 insertions(+)
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index 529e9b183eeb..30c144af894a 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -1256,6 +1256,10 @@ int bpf_iter_new_fd(struct bpf_link *link);
bool bpf_link_is_iter(struct bpf_link *link);
struct bpf_prog *bpf_iter_get_info(struct bpf_iter_meta *meta, bool in_stop);
int bpf_iter_run_prog(struct bpf_prog *prog, void *ctx);
+void bpf_iter_map_show_fdinfo(const struct bpf_iter_aux_info *aux,
+ struct seq_file *seq);
+int bpf_iter_map_fill_link_info(const struct bpf_iter_aux_info *aux,
+ struct bpf_link_info *info);
int bpf_percpu_hash_copy(struct bpf_map *map, void *key, void *value);
int bpf_percpu_array_copy(struct bpf_map *map, void *key, void *value);
diff --git a/kernel/bpf/map_iter.c b/kernel/bpf/map_iter.c
index af86048e5afd..714e74556aa2 100644
--- a/kernel/bpf/map_iter.c
+++ b/kernel/bpf/map_iter.c
@@ -149,6 +149,19 @@ static void bpf_iter_detach_map(struct bpf_iter_aux_info *aux)
bpf_map_put_with_uref(aux->map);
}
+void bpf_iter_map_show_fdinfo(const struct bpf_iter_aux_info *aux,
+ struct seq_file *seq)
+{
+ seq_printf(seq, "map_id:\t\t%u\n", aux->map->id);
nit: I think it's a bad idea to have two tabs here to align everything
visually, might make parsing unnecessarily harder
You are 100% correct. This is on purpose to please visual alignment.
I debate with myself to add extra '\t'. But yes, it is bad for tool
parsing. I will fix it in the next revision.
+}
+
+int bpf_iter_map_fill_link_info(const struct bpf_iter_aux_info *aux,
+ struct bpf_link_info *info)
+{
+ info->iter.map.map_id = aux->map->id;
+ return 0;
+}
+
DEFINE_BPF_ITER_FUNC(bpf_map_elem, struct bpf_iter_meta *meta,
struct bpf_map *map, void *key, void *value)
@@ -156,6 +169,8 @@ static const struct bpf_iter_reg bpf_map_elem_reg_info = {
.target = "bpf_map_elem",
.attach_target = bpf_iter_attach_map,
.detach_target = bpf_iter_detach_map,
+ .show_fdinfo = bpf_iter_map_show_fdinfo,
+ .fill_link_info = bpf_iter_map_fill_link_info,
.ctx_arg_info_size = 2,
.ctx_arg_info = {
{ offsetof(struct bpf_iter__bpf_map_elem, key),
diff --git a/net/core/bpf_sk_storage.c b/net/core/bpf_sk_storage.c
index b988f48153a4..281200dc0a01 100644
--- a/net/core/bpf_sk_storage.c
+++ b/net/core/bpf_sk_storage.c
@@ -1437,6 +1437,8 @@ static struct bpf_iter_reg bpf_sk_storage_map_reg_info = {
.target = "bpf_sk_storage_map",
.attach_target = bpf_iter_attach_map,
.detach_target = bpf_iter_detach_map,
+ .show_fdinfo = bpf_iter_map_show_fdinfo,
+ .fill_link_info = bpf_iter_map_fill_link_info,
.ctx_arg_info_size = 2,
.ctx_arg_info = {
{ offsetof(struct bpf_iter__bpf_sk_storage_map, sk),
--
2.24.1
