Re: [PATCH net 5/6] net/sched: Refactor qdisc_graft() for ingress and clsact Qdiscs

From: Jamal Hadi Salim
Date: Mon May 08 2023 - 07:30:12 EST


On Fri, May 5, 2023 at 8:15 PM Peilin Ye <yepeilin.cs@xxxxxxxxx> wrote:
>
> Grafting ingress and clsact Qdiscs does not need a for-loop in
> qdisc_graft(). Refactor it. No functional changes intended.
>
> Signed-off-by: Peilin Ye <peilin.ye@xxxxxxxxxxxxx>

Fixed John's email address.

This one i am not so sure; num_q = 1 implies it will run on the for
loop only once. I am not sure it improves readability either. Anyways
for the effort you put into it i am tossing a coin and saying:
Reviewed-by: Jamal Hadi Salim <jhs@xxxxxxxxxxxx>
Acked-by: Jamal Hadi Salim <jhs@xxxxxxxxxxxx>

cheers,
jamal


> net/sched/sch_api.c | 20 ++++++++++----------
> 1 file changed, 10 insertions(+), 10 deletions(-)
>
> diff --git a/net/sched/sch_api.c b/net/sched/sch_api.c
> index 49b9c1bbfdd9..f72a581666a2 100644
> --- a/net/sched/sch_api.c
> +++ b/net/sched/sch_api.c
> @@ -1073,12 +1073,12 @@ static int qdisc_graft(struct net_device *dev, struct Qdisc *parent,
>
> if (parent == NULL) {
> unsigned int i, num_q, ingress;
> + struct netdev_queue *dev_queue;
>
> ingress = 0;
> num_q = dev->num_tx_queues;
> if ((q && q->flags & TCQ_F_INGRESS) ||
> (new && new->flags & TCQ_F_INGRESS)) {
> - num_q = 1;
> ingress = 1;
> if (!dev_ingress_queue(dev)) {
> NL_SET_ERR_MSG(extack, "Device does not have an ingress queue");
> @@ -1094,18 +1094,18 @@ static int qdisc_graft(struct net_device *dev, struct Qdisc *parent,
> if (new && new->ops->attach && !ingress)
> goto skip;
>
> - for (i = 0; i < num_q; i++) {
> - struct netdev_queue *dev_queue = dev_ingress_queue(dev);
> -
> - if (!ingress)
> + if (!ingress) {
> + for (i = 0; i < num_q; i++) {
> dev_queue = netdev_get_tx_queue(dev, i);
> + old = dev_graft_qdisc(dev_queue, new);
>
> - old = dev_graft_qdisc(dev_queue, new);
> - if (new && i > 0)
> - qdisc_refcount_inc(new);
> -
> - if (!ingress)
> + if (new && i > 0)
> + qdisc_refcount_inc(new);
> qdisc_put(old);
> + }
> + } else {
> + dev_queue = dev_ingress_queue(dev);
> + old = dev_graft_qdisc(dev_queue, new);
> }
>
> skip:
> --
> 2.20.1
>