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| author | Xueming Feng <kuro@kuroa.me> | 2023-04-27 20:03:13 +0800 |
|---|---|---|
| committer | Martin KaFai Lau <martin.lau@kernel.org> | 2023-04-27 13:26:34 -0700 |
| commit | bf06c9393493a2862d4670beda2928423c774ff3 (patch) | |
| tree | 39bfd33a71e4d6b48f8fb089bd983b0e2033b0b3 /tools/bpf | |
| parent | 6ec7be9a2d2b09815f69fc2183ec31857eaa6e27 (diff) | |
| download | linux-stable-bf06c9393493a2862d4670beda2928423c774ff3.tar.gz linux-stable-bf06c9393493a2862d4670beda2928423c774ff3.tar.bz2 linux-stable-bf06c9393493a2862d4670beda2928423c774ff3.zip | |
bpftool: Dump map id instead of value for map_of_maps types
When using `bpftool map dump` with map_of_maps, it is usually
more convenient to show the inner map id instead of raw value.
We are changing the plain print behavior to show inner_map_id
instead of hex value, this would help with quick look up of
inner map with `bpftool map dump id <inner_map_id>`.
To avoid disrupting scripted behavior, we will add a new
`inner_map_id` field to json output instead of replacing value.
plain print:
```
$ bpftool map dump id 138
Without Patch:
key:
fc 00 00 00 00 00 00 00 00 00 00 00 00 00 00 05
27 16 06 00
value:
8b 00 00 00
Found 1 element
With Patch:
key:
fc 00 00 00 00 00 00 00 00 00 00 00 00 00 00 05
27 16 06 00
inner_map_id:
139
Found 1 element
```
json print:
```
$ bpftool -p map dump id 567
Without Patch:
[{
"key": ["0xc0","0x00","0x02","0x05","0x27","0x16","0x06","0x00"
],
"value": ["0x38","0x02","0x00","0x00"
]
}
]
With Patch:
[{
"key": ["0xc0","0x00","0x02","0x05","0x27","0x16","0x06","0x00"
],
"value": ["0x38","0x02","0x00","0x00"
],
"inner_map_id": 568
}
]
```
Signed-off-by: Xueming Feng <kuro@kuroa.me>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/r/20230427120313.43574-1-kuro@kuroa.me
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Diffstat (limited to 'tools/bpf')
| -rw-r--r-- | tools/bpf/bpftool/map.c | 12 |
1 files changed, 10 insertions, 2 deletions
diff --git a/tools/bpf/bpftool/map.c b/tools/bpf/bpftool/map.c index aaeb8939e137..ae9e822aa3fe 100644 --- a/tools/bpf/bpftool/map.c +++ b/tools/bpf/bpftool/map.c @@ -139,6 +139,9 @@ static void print_entry_json(struct bpf_map_info *info, unsigned char *key, print_hex_data_json(key, info->key_size); jsonw_name(json_wtr, "value"); print_hex_data_json(value, info->value_size); + if (map_is_map_of_maps(info->type)) + jsonw_uint_field(json_wtr, "inner_map_id", + *(unsigned int *)value); if (btf) { struct btf_dumper d = { .btf = btf, @@ -259,8 +262,13 @@ static void print_entry_plain(struct bpf_map_info *info, unsigned char *key, } if (info->value_size) { - printf("value:%c", break_names ? '\n' : ' '); - fprint_hex(stdout, value, info->value_size, " "); + if (map_is_map_of_maps(info->type)) { + printf("inner_map_id:%c", break_names ? '\n' : ' '); + printf("%u ", *(unsigned int *)value); + } else { + printf("value:%c", break_names ? '\n' : ' '); + fprint_hex(stdout, value, info->value_size, " "); + } } printf("\n"); |