From: Björn Töpel Date: Wed, 19 Dec 2018 12:09:31 +0000 (+0100) Subject: xsk: simplify AF_XDP socket teardown X-Git-Tag: v5.4-rc1~1957^2~15^2~6 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=e2ce3674883ecba2605370404208c9d4a07ae1c3;p=platform%2Fkernel%2Flinux-rpi.git xsk: simplify AF_XDP socket teardown Prior this commit, when the struct socket object was being released, the UMEM did not have its reference count decreased. Instead, this was done in the struct sock sk_destruct function. There is no reason to keep the UMEM reference around when the socket is being orphaned, so in this patch the xdp_put_mem is called in the xsk_release function. This results in that the xsk_destruct function can be removed! Note that, it still holds that a struct xsk_sock reference might still linger in the XSKMAP after the UMEM is released, e.g. if a user does not clear the XSKMAP prior to closing the process. This sock will be in a "released" zombie like state, until the XSKMAP is removed. Signed-off-by: Björn Töpel Signed-off-by: Daniel Borkmann --- diff --git a/net/xdp/xsk.c b/net/xdp/xsk.c index 07156f4..a032684 100644 --- a/net/xdp/xsk.c +++ b/net/xdp/xsk.c @@ -366,6 +366,7 @@ static int xsk_release(struct socket *sock) xskq_destroy(xs->rx); xskq_destroy(xs->tx); + xdp_put_umem(xs->umem); sock_orphan(sk); sock->sk = NULL; @@ -713,18 +714,6 @@ static const struct proto_ops xsk_proto_ops = { .sendpage = sock_no_sendpage, }; -static void xsk_destruct(struct sock *sk) -{ - struct xdp_sock *xs = xdp_sk(sk); - - if (!sock_flag(sk, SOCK_DEAD)) - return; - - xdp_put_umem(xs->umem); - - sk_refcnt_debug_dec(sk); -} - static int xsk_create(struct net *net, struct socket *sock, int protocol, int kern) { @@ -751,9 +740,6 @@ static int xsk_create(struct net *net, struct socket *sock, int protocol, sk->sk_family = PF_XDP; - sk->sk_destruct = xsk_destruct; - sk_refcnt_debug_inc(sk); - sock_set_flag(sk, SOCK_RCU_FREE); xs = xdp_sk(sk);