This is a note to let you know that I've just added the patch titled ice: xsk: Force rings to be sized to power of 2 to the 5.15-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: ice-xsk-force-rings-to-be-sized-to-power-of-2.patch and it can be found in the queue-5.15 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit d9f7972c00005c0f0ed38d8f41b27c2e01c907d1 Author: Maciej Fijalkowski <maciej.fijalkowski@xxxxxxxxx> Date: Tue Jan 25 17:04:40 2022 +0100 ice: xsk: Force rings to be sized to power of 2 [ Upstream commit 296f13ff3854535009a185aaf8e3603266d39d94 ] With the upcoming introduction of batching to XSK data path, performance wise it will be the best to have the ring descriptor count to be aligned to power of 2. Check if ring sizes that user is going to attach the XSK socket fulfill the condition above. For Tx side, although check is being done against the Tx queue and in the end the socket will be attached to the XDP queue, it is fine since XDP queues get the ring->count setting from Tx queues. Suggested-by: Alexander Lobakin <alexandr.lobakin@xxxxxxxxx> Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@xxxxxxxxx> Signed-off-by: Daniel Borkmann <daniel@xxxxxxxxxxxxx> Reviewed-by: Alexander Lobakin <alexandr.lobakin@xxxxxxxxx> Acked-by: Magnus Karlsson <magnus.karlsson@xxxxxxxxx> Link: https://lore.kernel.org/bpf/20220125160446.78976-3-maciej.fijalkowski@xxxxxxxxx Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/net/ethernet/intel/ice/ice_xsk.c b/drivers/net/ethernet/intel/ice/ice_xsk.c index 5581747947e57..0348cc4265034 100644 --- a/drivers/net/ethernet/intel/ice/ice_xsk.c +++ b/drivers/net/ethernet/intel/ice/ice_xsk.c @@ -321,6 +321,13 @@ int ice_xsk_pool_setup(struct ice_vsi *vsi, struct xsk_buff_pool *pool, u16 qid) bool if_running, pool_present = !!pool; int ret = 0, pool_failure = 0; + if (!is_power_of_2(vsi->rx_rings[qid]->count) || + !is_power_of_2(vsi->tx_rings[qid]->count)) { + netdev_err(vsi->netdev, "Please align ring sizes to power of 2\n"); + pool_failure = -EINVAL; + goto failure; + } + if_running = netif_running(vsi->netdev) && ice_is_xdp_ena_vsi(vsi); if (if_running) { @@ -343,6 +350,7 @@ int ice_xsk_pool_setup(struct ice_vsi *vsi, struct xsk_buff_pool *pool, u16 qid) netdev_err(vsi->netdev, "ice_qp_ena error = %d\n", ret); } +failure: if (pool_failure) { netdev_err(vsi->netdev, "Could not %sable buffer pool, error = %d\n", pool_present ? "en" : "dis", pool_failure);