On 2020-07-02 15:19, Magnus Karlsson wrote:
Add support to share a umem between different devices. This mode can be invoked with the XDP_SHARED_UMEM bind flag. Previously, sharing was only supported within the same device. Note that when sharing a umem between devices, just as in the case of sharing a umem between queue ids, you need to create a fill ring and a completion ring and tie them to the socket (with two setsockopts, one for each ring) before you do the bind with the XDP_SHARED_UMEM flag. This so that the single-producer single-consumer semantics of the rings can be upheld.
I also wonder what performance numbers you see when doing forwarding with xsk_fwd between two queues of the same netdev and between two netdevs. Could you share (compared to some baseline like xdpsock -l)?
Signed-off-by: Magnus Karlsson <magnus.karls...@intel.com> --- net/xdp/xsk.c | 11 ++++------- 1 file changed, 4 insertions(+), 7 deletions(-) diff --git a/net/xdp/xsk.c b/net/xdp/xsk.c index 1abc222..b240221 100644 --- a/net/xdp/xsk.c +++ b/net/xdp/xsk.c @@ -692,14 +692,11 @@ static int xsk_bind(struct socket *sock, struct sockaddr *addr, int addr_len) sockfd_put(sock); goto out_unlock; } - if (umem_xs->dev != dev) { - err = -EINVAL; - sockfd_put(sock); - goto out_unlock; - }- if (umem_xs->queue_id != qid) {- /* Share the umem with another socket on another qid */ + if (umem_xs->queue_id != qid || umem_xs->dev != dev) { + /* Share the umem with another socket on another qid + * and/or device. + */ new_pool = xp_assign_umem(xs->pool, umem_xs->umem); if (!new_pool) { sockfd_put(sock);
