From: Magnus Karlsson <magnus.karlsson@intel.com>
Date: Mon, 4 Jun 2018 13:57:15 +0200
Subject: samples/bpf: minor *_nb_free performance fix
Patch-mainline: v4.18-rc1
Git-commit: a65ea68b8dd92fea86d2b8ca7e43caeaa5ddcdff
References: bsc#1109837
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
samples/bpf/xdpsock_user.c | 8 +++++---
1 file changed, 5 insertions(+), 3 deletions(-)
--- a/samples/bpf/xdpsock_user.c
+++ b/samples/bpf/xdpsock_user.c
@@ -157,15 +157,15 @@ static const char pkt_data[] =
static inline u32 umem_nb_free(struct xdp_umem_uqueue *q, u32 nb)
{
- u32 free_entries = q->size - (q->cached_prod - q->cached_cons);
+ u32 free_entries = q->cached_cons - q->cached_prod;
if (free_entries >= nb)
return free_entries;
/* Refresh the local tail pointer */
- q->cached_cons = *q->consumer;
+ q->cached_cons = *q->consumer + q->size;
- return q->size - (q->cached_prod - q->cached_cons);
+ return q->cached_cons - q->cached_prod;
}
static inline u32 xq_nb_free(struct xdp_uqueue *q, u32 ndescs)
@@ -439,6 +439,7 @@ static struct xdp_umem *xdp_umem_configu
umem->fq.producer = umem->fq.map + off.fr.producer;
umem->fq.consumer = umem->fq.map + off.fr.consumer;
umem->fq.ring = umem->fq.map + off.fr.desc;
+ umem->fq.cached_cons = FQ_NUM_DESCS;
umem->cq.map = mmap(0, off.cr.desc +
CQ_NUM_DESCS * sizeof(u64),
@@ -535,6 +536,7 @@ static struct xdpsock *xsk_configure(str
xsk->tx.producer = xsk->tx.map + off.tx.producer;
xsk->tx.consumer = xsk->tx.map + off.tx.consumer;
xsk->tx.ring = xsk->tx.map + off.tx.desc;
+ xsk->tx.cached_cons = NUM_DESCS;
sxdp.sxdp_family = PF_XDP;
sxdp.sxdp_ifindex = opt_ifindex;