| Message ID | 20250402162750.1671155-1-tavip@google.com (mailing list archive) |
|---|---|
| Headers | show |
| Series | net_sched: sch_sfq: reject a derived limit of 1 | expand |
On Wed, Apr 02, 2025 at 09:27:47AM -0700, Octavian Purdila wrote: > Because sfq parameters can influence each other there can be > situations where although the user sets a limit of 2 it can be lowered > to 1: > > $ tc qdisc add dev dummy0 handle 1: root sfq limit 2 flows 1 depth 1 > $ tc qdisc show dev dummy0 > qdisc sfq 1: dev dummy0 root refcnt 2 limit 1p quantum 1514b depth 1 divisor 1024 > > $ tc qdisc add dev dummy0 handle 1: root sfq limit 2 flows 10 depth 1 divisor 1 > $ tc qdisc show dev dummy0 > qdisc sfq 2: root refcnt 2 limit 1p quantum 1514b depth 1 divisor 1 > > As a limit of 1 is invalid, this patch series moves the limit > validation to after all configuration changes have been done. To do > so, the configuration is done in a temporary work area then applied to > the internal state. > > The patch series also adds new test cases. Acked-by: Cong Wang <xiyou.wangcong@gmail.com> Please carry this Ack when you send v3. Thanks.
Because sfq parameters can influence each other there can be situations where although the user sets a limit of 2 it can be lowered to 1: $ tc qdisc add dev dummy0 handle 1: root sfq limit 2 flows 1 depth 1 $ tc qdisc show dev dummy0 qdisc sfq 1: dev dummy0 root refcnt 2 limit 1p quantum 1514b depth 1 divisor 1024 $ tc qdisc add dev dummy0 handle 1: root sfq limit 2 flows 10 depth 1 divisor 1 $ tc qdisc show dev dummy0 qdisc sfq 2: root refcnt 2 limit 1p quantum 1514b depth 1 divisor 1 As a limit of 1 is invalid, this patch series moves the limit validation to after all configuration changes have been done. To do so, the configuration is done in a temporary work area then applied to the internal state. The patch series also adds new test cases. Changes in v2: - remove tmp struct and directly use local variables v1: https://lore.kernel.org/all/20250328201634.3876474-1-tavip@google.com/ Octavian Purdila (3): net_sched: sch_sfq: use a temporary work area for validating configuration net_sched: sch_sfq: move the limit validation selftests/tc-testing: sfq: check that a derived limit of 1 is rejected net/sched/sch_sfq.c | 68 ++++++++++++++----- .../tc-testing/tc-tests/qdiscs/sfq.json | 36 ++++++++++ 2 files changed, 88 insertions(+), 16 deletions(-)