xsk: Add API to check for available entries in FQ

Add a function that checks whether the Fill Ring has the specified
amount of descriptors available. It will be useful for mlx5e that wants
to check in advance, whether it can allocate a bulk of RX descriptors,
to get the best performance.

Signed-off-by: Maxim Mikityanskiy <[email protected]>
Signed-off-by: Tariq Toukan <[email protected]>
Acked-by: Saeed Mahameed <[email protected]>
Acked-by: Björn Töpel <[email protected]>
Signed-off-by: Daniel Borkmann <[email protected]>
This commit is contained in:
Maxim Mikityanskiy 2019-06-26 17:35:24 +03:00 • committed by Daniel Borkmann
commit d57d76428a
3 changed files with 41 additions and 0 deletions

View file

@ -37,6 +37,12 @@ bool xsk_is_setup_for_bpf_map(struct xdp_sock *xs)
READ_ONCE(xs->umem->fq);
}
bool xsk_umem_has_addrs(struct xdp_umem *umem, u32 cnt)
{
return xskq_has_addrs(umem->fq, cnt);
}
EXPORT_SYMBOL(xsk_umem_has_addrs);
u64 *xsk_umem_peek_addr(struct xdp_umem *umem, u64 *addr)
{
return xskq_peek_addr(umem->fq, addr);

View file

@ -117,6 +117,20 @@ static inline u32 xskq_nb_free(struct xsk_queue *q, u32 producer, u32 dcnt)
return q->nentries - (producer - q->cons_tail);
}
static inline bool xskq_has_addrs(struct xsk_queue *q, u32 cnt)
{
u32 entries = q->prod_tail - q->cons_tail;
if (entries >= cnt)
return true;
/* Refresh the local pointer. */
q->prod_tail = READ_ONCE(q->ring->producer);
entries = q->prod_tail - q->cons_tail;
return entries >= cnt;
}
/* UMEM queue */
static inline bool xskq_is_valid_addr(struct xsk_queue *q, u64 addr)