| Message ID | 20240305053310.815877-5-kuba@kernel.org (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | c0111878d45e3bb8779886fbf956b574bac8a3aa |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | tools: ynl: add --dbg-small-recv for easier kernel testing | expand |
Jakub Kicinski <kuba@kernel.org> writes: > Most "production" netlink clients use large buffers to > make dump efficient, which means that handling of dump > continuation in the kernel is not very well tested. > > Add an option for debugging / testing handling of dumps. > It enables printing of extra netlink-level debug and > lowers the recv() buffer size in one go. When used > without any argument (--dbg-small-recv) it picks > a very small default (4000), explicit size can be set, > too (--dbg-small-recv 5000). > > Example: > > $ ./cli.py [...] --dbg-small-recv > Recv: read 3712 bytes, 29 messages > nl_len = 128 (112) nl_flags = 0x0 nl_type = 19 > [...] > nl_len = 128 (112) nl_flags = 0x0 nl_type = 19 > Recv: read 3968 bytes, 31 messages > nl_len = 128 (112) nl_flags = 0x0 nl_type = 19 > [...] > nl_len = 128 (112) nl_flags = 0x0 nl_type = 19 > Recv: read 532 bytes, 5 messages > nl_len = 128 (112) nl_flags = 0x0 nl_type = 19 > [...] > nl_len = 128 (112) nl_flags = 0x0 nl_type = 19 > nl_len = 20 (4) nl_flags = 0x2 nl_type = 3 > > (the [...] are edits to shorten the commit message). > > Note that the first message of the dump is sized conservatively > by the kernel. > > Signed-off-by: Jakub Kicinski <kuba@kernel.org> Reviewed-by: Donald Hunter <donald.hunter@gmail.com>
diff --git a/tools/net/ynl/cli.py b/tools/net/ynl/cli.py index 0f8239979670..e8a65fbc3698 100755 --- a/tools/net/ynl/cli.py +++ b/tools/net/ynl/cli.py @@ -38,6 +38,8 @@ from lib import YnlFamily, Netlink const=Netlink.NLM_F_APPEND) parser.add_argument('--process-unknown', action=argparse.BooleanOptionalAction) parser.add_argument('--output-json', action='store_true') + parser.add_argument('--dbg-small-recv', default=0, const=4000, + action='store', nargs='?', type=int) args = parser.parse_args() def output(msg): @@ -53,7 +55,10 @@ from lib import YnlFamily, Netlink if args.json_text: attrs = json.loads(args.json_text) - ynl = YnlFamily(args.spec, args.schema, args.process_unknown) + ynl = YnlFamily(args.spec, args.schema, args.process_unknown, + recv_size=args.dbg_small_recv) + if args.dbg_small_recv: + ynl.set_recv_dbg(True) if args.ntf: ynl.ntf_subscribe(args.ntf)
Most "production" netlink clients use large buffers to make dump efficient, which means that handling of dump continuation in the kernel is not very well tested. Add an option for debugging / testing handling of dumps. It enables printing of extra netlink-level debug and lowers the recv() buffer size in one go. When used without any argument (--dbg-small-recv) it picks a very small default (4000), explicit size can be set, too (--dbg-small-recv 5000). Example: $ ./cli.py [...] --dbg-small-recv Recv: read 3712 bytes, 29 messages nl_len = 128 (112) nl_flags = 0x0 nl_type = 19 [...] nl_len = 128 (112) nl_flags = 0x0 nl_type = 19 Recv: read 3968 bytes, 31 messages nl_len = 128 (112) nl_flags = 0x0 nl_type = 19 [...] nl_len = 128 (112) nl_flags = 0x0 nl_type = 19 Recv: read 532 bytes, 5 messages nl_len = 128 (112) nl_flags = 0x0 nl_type = 19 [...] nl_len = 128 (112) nl_flags = 0x0 nl_type = 19 nl_len = 20 (4) nl_flags = 0x2 nl_type = 3 (the [...] are edits to shorten the commit message). Note that the first message of the dump is sized conservatively by the kernel. Signed-off-by: Jakub Kicinski <kuba@kernel.org> --- tools/net/ynl/cli.py | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-)