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* [PATCH 0/3] ss: pretty-printing BPF socket-local storage
@ 2023-11-28  2:30 Quentin Deslandes
  2023-11-28  2:30 ` [PATCH 1/3] ss: prevent "Process" column from being printed unless requested Quentin Deslandes
                   ` (3 more replies)
  0 siblings, 4 replies; 10+ messages in thread
From: Quentin Deslandes @ 2023-11-28  2:30 UTC (permalink / raw)
  To: netdev; +Cc: David Ahern, Martin KaFai Lau, Quentin Deslandes

BPF allows programs to store socket-specific data using
BPF_MAP_TYPE_SK_STORAGE maps. The data is attached to the socket itself,
and Martin added INET_DIAG_REQ_SK_BPF_STORAGES, so it can be fetched
using the INET_DIAG mechanism.

Currently, ss doesn't request the socket-local data, this patch aims to
fix this.

The first patch fixes a bug where the "Process" column would always be
printed on ss' output, even if --processes/-p is not used.

Patch #2 requests the socket-local data for the requested map ID
(--bpf-map-id=) or all the maps (--bpf-maps). It then prints the map_id
in a dedicated column.

Patch #3 uses libbpf and BTF to pretty print the map's content, like
`bpftool map dump` would do.

While I think it makes sense for ss to provide the socket-local storage
content for the sockets, it's difficult to conciliate the column-based
output of ss and having readable socket-local data. Hence, the
socket-local data is printed in a readable fashion over multiple lines
under its socket statistics, independently of the column-based approach.

Here is an example of ss' output with --bpf-maps:
[...]
ESTAB                  2960280             0 [...]
    map_id: 259 [
        (struct my_sk_storage) {
            .field_hh = (char)127,
            .<anon> = (union <anon>) {
                .a = (int)0,
                .b = (int)0,
            },
        },
    ]

Quentin Deslandes (3):
  ss: prevent "Process" column from being printed unless requested
  ss: add support for BPF socket-local storage
  ss: pretty-print BPF socket-local storage

 misc/ss.c | 822 +++++++++++++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 818 insertions(+), 4 deletions(-)

-- 
2.43.0


^ permalink raw reply	[flat|nested] 10+ messages in thread

end of thread, other threads:[~2023-12-08 17:27 UTC | newest]

Thread overview: 10+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2023-11-28  2:30 [PATCH 0/3] ss: pretty-printing BPF socket-local storage Quentin Deslandes
2023-11-28  2:30 ` [PATCH 1/3] ss: prevent "Process" column from being printed unless requested Quentin Deslandes
2023-11-29  0:20   ` David Ahern
2023-11-28  2:30 ` [PATCH 2/3] ss: add support for BPF socket-local storage Quentin Deslandes
2023-11-28 23:35   ` Martin KaFai Lau
2023-11-28  2:30 ` [PATCH 3/3] ss: pretty-print " Quentin Deslandes
2023-11-28 23:42   ` Martin KaFai Lau
2023-11-28 22:43 ` [PATCH 0/3] ss: pretty-printing " Stephen Hemminger
2023-12-08 15:01   ` Quentin Deslandes
2023-12-08 17:27     ` Stephen Hemminger

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