[PATCH bpf] xsk: inherit need_wakeup flag for shared sockets

From: Jalal Mostafa
Date: Mon Sep 19 2022 - 15:25:05 EST


The flag for need_wakeup is not set for xsks with `XDP_SHARED_UMEM`
flag and of different queue ids and/or devices. They should inherit
the flag from the first socket buffer pool since no flags can be
specified once `XDP_SHARED_UMEM` is specified. The issue is fixed
by creating a new function `xp_create_and_assign_umem_shared` to
create xsk_buff_pool for xsks with the shared umem flag set.

Signed-off-by: Jalal Mostafa <jalal.a.mostapha@xxxxxxxxx>
---
include/net/xsk_buff_pool.h | 2 ++
net/xdp/xsk.c | 3 +--
net/xdp/xsk_buff_pool.c | 15 +++++++++++++++
3 files changed, 18 insertions(+), 2 deletions(-)

diff --git a/include/net/xsk_buff_pool.h b/include/net/xsk_buff_pool.h
index 647722e847b4..917cfef9d355 100644
--- a/include/net/xsk_buff_pool.h
+++ b/include/net/xsk_buff_pool.h
@@ -93,6 +93,8 @@ struct xsk_buff_pool {
/* AF_XDP core. */
struct xsk_buff_pool *xp_create_and_assign_umem(struct xdp_sock *xs,
struct xdp_umem *umem);
+struct xsk_buff_pool *xp_create_and_assign_umem_shared(struct xdp_sock *xs,
+ struct xdp_sock *umem_xs);
int xp_assign_dev(struct xsk_buff_pool *pool, struct net_device *dev,
u16 queue_id, u16 flags);
int xp_assign_dev_shared(struct xsk_buff_pool *pool, struct xdp_umem *umem,
diff --git a/net/xdp/xsk.c b/net/xdp/xsk.c
index 5b4ce6ba1bc7..a415db88e8e5 100644
--- a/net/xdp/xsk.c
+++ b/net/xdp/xsk.c
@@ -946,8 +946,7 @@ static int xsk_bind(struct socket *sock, struct sockaddr *addr, int addr_len)
/* Share the umem with another socket on another qid
* and/or device.
*/
- xs->pool = xp_create_and_assign_umem(xs,
- umem_xs->umem);
+ xs->pool = xp_create_and_assign_umem_shared(xs, umem_xs);
if (!xs->pool) {
err = -ENOMEM;
sockfd_put(sock);
diff --git a/net/xdp/xsk_buff_pool.c b/net/xdp/xsk_buff_pool.c
index a71a8c6edf55..7d5b0bd8d953 100644
--- a/net/xdp/xsk_buff_pool.c
+++ b/net/xdp/xsk_buff_pool.c
@@ -112,6 +112,21 @@ struct xsk_buff_pool *xp_create_and_assign_umem(struct xdp_sock *xs,
return NULL;
}

+struct xsk_buff_pool *xp_create_and_assign_umem_shared(struct xdp_sock *xs,
+ struct xdp_sock *umem_xs)
+{
+ struct xdp_umem *umem = umem_xs->umem;
+ struct xsk_buff_pool *pool = xp_create_and_assign_umem(xs, umem);
+
+ if (!pool)
+ goto out;
+
+ pool->uses_need_wakeup = umem_xs->pool->uses_need_wakeup;
+
+out:
+ return pool;
+}
+
void xp_set_rxq_info(struct xsk_buff_pool *pool, struct xdp_rxq_info *rxq)
{
u32 i;
--
2.34.1