On Wed, 2016-08-17 at 12:36 -0700, John Fastabend wrote:
> The qdisc_reset operation depends on the qdisc lock at the moment
> to halt any additions to gso_skb and statistics while the list is
> free'd and the stats zeroed.
...
> Signed-off-by: John Fastabend <john.r.fastab...@intel.com>
> ---
> net/sched/sch_generic.c | 45 +++++++++++++++++++++++++++++++++++----------
> 1 file changed, 35 insertions(+), 10 deletions(-)
>
> diff --git a/net/sched/sch_generic.c b/net/sched/sch_generic.c
> index 3b9a21f..29238c4 100644
> --- a/net/sched/sch_generic.c
> +++ b/net/sched/sch_generic.c
> @@ -737,6 +737,20 @@ void qdisc_reset(struct Qdisc *qdisc)
> kfree_skb(qdisc->skb_bad_txq);
> qdisc->skb_bad_txq = NULL;
>
> + if (qdisc->gso_cpu_skb) {
> + int i;
> +
> + for_each_possible_cpu(i) {
> + struct gso_cell *cell;
> +
> + cell = per_cpu_ptr(qdisc->gso_cpu_skb, i);
> + if (cell) {
> + kfree_skb_list(cell->skb);
> + cell = NULL;
You probably wanted :
cell->skb = NULL;
> + }
> + }
> + }
> +
> if (qdisc->gso_skb) {
> kfree_skb_list(qdisc->gso_skb);
> qdisc->gso_skb = NULL;
> @@ -812,10 +826,6 @@ struct Qdisc *dev_graft_qdisc(struct netdev_queue
> *dev_queue,
> root_lock = qdisc_lock(oqdisc);
> spin_lock_bh(root_lock);
>
> - /* Prune old scheduler */
> - if (oqdisc && atomic_read(&oqdisc->refcnt) <= 1)
> - qdisc_reset(oqdisc);
> -
>
This probably belongs to a separate patch, before any per cpu / lockless
qdisc changes ?
