[PATCH net-next v5 4/5] net: sched: rename QDISC_DROP_CAKE_FLOOD to QDISC_DROP_FLOOD_PROTECTION
From: Jesper Dangaard Brouer <hawk@kernel.org>
Date: 2026-02-26 13:45:18
Also in:
bpf
Subsystem:
cake qdisc, networking [general], tc subsystem, the rest · Maintainers:
Toke Høiland-Jørgensen, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Jamal Hadi Salim, Jiri Pirko, Linus Torvalds
Rename QDISC_DROP_CAKE_FLOOD to QDISC_DROP_FLOOD_PROTECTION to use a generic name without embedding the qdisc name. This follows the principle that drop reasons should describe the drop mechanism rather than being tied to a specific qdisc implementation. The flood protection drop reason is used by qdiscs implementing probabilistic drop algorithms (like BLUE) that detect unresponsive flows indicating potential DoS or flood attacks. CAKE uses this via its Cobalt AQM component. Signed-off-by: Jesper Dangaard Brouer <hawk@kernel.org> Reviewed-by: Toke Høiland-Jørgensen <redacted> --- include/net/dropreason-qdisc.h | 11 ++++++----- net/sched/sch_cake.c | 2 +- 2 files changed, 7 insertions(+), 6 deletions(-)
diff --git a/include/net/dropreason-qdisc.h b/include/net/dropreason-qdisc.h
index a167302e79e5..84f19a51382c 100644
--- a/include/net/dropreason-qdisc.h
+++ b/include/net/dropreason-qdisc.h@@ -10,7 +10,7 @@ FN(OVERLIMIT) \ FN(CONGESTED) \ FN(MAXFLOWS) \ - FN(CAKE_FLOOD) \ + FN(FLOOD_PROTECTION) \ FN(BAND_LIMIT) \ FN(HORIZON_LIMIT) \ FN(FLOW_LIMIT) \
@@ -68,11 +68,12 @@ enum qdisc_drop_reason { */ QDISC_DROP_MAXFLOWS, /** - * @QDISC_DROP_CAKE_FLOOD: CAKE qdisc dropped packet due to flood - * protection mechanism (BLUE algorithm). This indicates potential - * DoS/flood attack or unresponsive flow behavior. + * @QDISC_DROP_FLOOD_PROTECTION: packet dropped by flood protection + * mechanism detecting unresponsive flows (potential DoS/flood). + * Used by qdiscs implementing probabilistic drop algorithms like + * BLUE (e.g., CAKE's Cobalt AQM). */ - QDISC_DROP_CAKE_FLOOD, + QDISC_DROP_FLOOD_PROTECTION, /** * @QDISC_DROP_BAND_LIMIT: packet dropped because the priority band's * limit was reached. Used by qdiscs with priority bands that have
diff --git a/net/sched/sch_cake.c b/net/sched/sch_cake.c
index 6e1d3be76201..5394d967c554 100644
--- a/net/sched/sch_cake.c
+++ b/net/sched/sch_cake.c@@ -573,7 +573,7 @@ static enum qdisc_drop_reason cobalt_should_drop(struct cobalt_vars *vars, /* Simple BLUE implementation. Lack of ECN is deliberate. */ if (vars->p_drop && reason == QDISC_DROP_UNSPEC && get_random_u32() < vars->p_drop) - reason = QDISC_DROP_CAKE_FLOOD; + reason = QDISC_DROP_FLOOD_PROTECTION; /* Overload the drop_next field as an activity timeout */ if (!vars->count)