[PATCH iproute2] q_cake: allow changing to diffserv3

[PATCH iproute2] q_cake: allow changing to diffserv3

[Kevin Bracey]

A diffserv3 option (enum value 0) was never sent to the kernel, so it
was not possible to use "tc qdisc change" to select it.

This also meant that were also relying on the kernel's default being
diffserv3 when adding. If the default were to change, we wouldn't have
been able to request diffserv3 explicitly.

Signed-off-by: Kevin Bracey <kevin@bracey.fi>
---
 tc/q_cake.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tc/q_cake.c b/tc/q_cake.c
index 4cfc1c00..c438b765 100644
--- a/tc/q_cake.c
+++ b/tc/q_cake.c
@@ -95,7 +95,7 @@ static int cake_parse_opt(struct qdisc_util *qu, int argc, char **argv,
 	bool overhead_override = false;
 	bool overhead_set = false;
 	unsigned int interval = 0;
-	unsigned int diffserv = 0;
+	int diffserv = -1;
 	unsigned int memlimit = 0;
 	unsigned int fwmark = 0;
 	unsigned int target = 0;
@@ -356,7 +356,7 @@ static int cake_parse_opt(struct qdisc_util *qu, int argc, char **argv,
 	if (bandwidth || unlimited)
 		addattr_l(n, 1024, TCA_CAKE_BASE_RATE64, &bandwidth,
 			  sizeof(bandwidth));
-	if (diffserv)
+	if (diffserv != -1)
 		addattr_l(n, 1024, TCA_CAKE_DIFFSERV_MODE, &diffserv,
 			  sizeof(diffserv));
 	if (atm != -1)
-- 
2.25.1

Re: [PATCH iproute2] q_cake: allow changing to diffserv3

[Toke Høiland-Jørgensen]

Kevin Bracey <kevin@bracey.fi> writes:

> A diffserv3 option (enum value 0) was never sent to the kernel, so it
> was not possible to use "tc qdisc change" to select it.
>
> This also meant that were also relying on the kernel's default being
> diffserv3 when adding. If the default were to change, we wouldn't have
> been able to request diffserv3 explicitly.
>
> Signed-off-by: Kevin Bracey <kevin@bracey.fi>

Yeah, that should probably be fixed; thanks!

Acked-by: Toke Høiland-Jørgensen <toke@toke.dk>