Re: [PATCH net-next 01/12] ptr_ring: keep consumer_head valid at all times

On 01/25/2018 03:36 PM, Michael S. Tsirkin wrote:

The comment near __ptr_ring_peek says:

 * If ring is never resized, and if the pointer is merely
 * tested, there's no need to take the lock - see e.g.  __ptr_ring_empty.

but this was in fact never possible since consumer_head would sometimes
point outside the ring. Refactor the code so that it's always
pointing within a ring.

Fixes: c5ad119fb6c09 ("net: sched: pfifo_fast use skb_array")
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
 include/linux/ptr_ring.h | 25 ++++++++++++++++---------
 1 file changed, 16 insertions(+), 9 deletions(-)

Thanks for fixing this up.

Acked-by: John Fastabend <john.fastabend@gmail.com>