avoids outputting a series of
value:
No space left on device
The value itself is not wrong but bpf_fd_reuseport_array_lookup_elem() can
only return it if the map was created with value_size = 8. There's nothing
bpftool can do about it. Instead of repeating this error for every key in
the map, print the error once, print an explanatory message and exit.
Signed-off-by: Benjamin Poirier <bpoir...@suse.com>
---
Note that this will lead to a merge conflict if the patch "bpftool: Fix
errno variable usage" is merged in the bpf branch:
<<<<<<< HEAD
if (lookup_errno == ENOENT)
=======
if (errno == ENOENT) {
>>>>>>> bpf-next
The resolution should be trivial:
if (lookup_errno == ENOENT) {
tools/bpf/bpftool/map.c | 21 +++++++++++++++------
1 file changed, 15 insertions(+), 6 deletions(-)
diff --git a/tools/bpf/bpftool/map.c b/tools/bpf/bpftool/map.c
index e96903078991..bb648e42923c 100644
--- a/tools/bpf/bpftool/map.c
+++ b/tools/bpf/bpftool/map.c
@@ -684,7 +684,6 @@ static int dump_map_elem(int fd, void *key, void *value,
struct bpf_map_info *map_info, struct btf *btf,
json_writer_t *btf_wtr)
{
- int num_elems = 0;
int lookup_errno;
if (!bpf_map_lookup_elem(fd, key, value)) {
@@ -702,9 +701,8 @@ static int dump_map_elem(int fd, void *key, void *value,
} else {
print_entry_plain(map_info, key, value);
}
- num_elems++;
}
- return num_elems;
+ return 1;
}
/* lookup error handling */
@@ -722,11 +720,13 @@ static int dump_map_elem(int fd, void *key, void *value,
jsonw_string_field(json_wtr, "error", strerror(lookup_errno));
jsonw_end_object(json_wtr);
} else {
- if (errno == ENOENT)
+ if (errno == ENOENT) {
print_entry_plain(map_info, key, NULL);
- else
+ } else {
print_entry_error(map_info, key,
strerror(lookup_errno));
+ return -lookup_errno;
+ }
}
return 0;
@@ -787,7 +787,16 @@ static int do_dump(int argc, char **argv)
err = 0;
break;
}
- num_elems += dump_map_elem(fd, key, value, &info, btf, btf_wtr);
+ err = dump_map_elem(fd, key, value, &info, btf, btf_wtr);
+ /* bpf_fd_reuseport_array_lookup_elem() can only return a
+ * value if the map's value_size == 8
+ */
+ if (info.type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY &&
+ info.value_size != 8 && err == -ENOSPC) {
+ p_err("cannot dump REUSEPORT_SOCKARRAY map with
value_size != 8");
+ goto exit_free;
+ }
+ num_elems += err;
prev_key = key;
}
--
2.21.0
