Re: [PATCH v2 net-next 2/9] xdp: initialize xdp_buff mb bit to 0 in all XDP drivers
From: Jesper Dangaard Brouer <hidden>
Date: 2020-09-04 07:36:00
Also in:
bpf, intel-wired-lan
On Thu, 3 Sep 2020 22:58:46 +0200 Lorenzo Bianconi [off-list ref] wrote:
quoted hunk ↗ jump to hunk
diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c index 0b675c34ce49..20c8fd3cd4a3 100644 --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c@@ -2298,6 +2298,7 @@ static int ixgbe_clean_rx_irq(struct ixgbe_q_vector *q_vector, #if (PAGE_SIZE < 8192) xdp.frame_sz = ixgbe_rx_frame_truesize(rx_ring, 0); #endif + xdp.mb = 0; while (likely(total_rx_packets < budget)) { union ixgbe_adv_rx_desc *rx_desc;
In this ixgbe driver you are smart and init the xdp.mb bit outside the (like xdp.frame_sz, when frame_sz is constant). This is a nice optimization, but the driver developer that adds XDP multi-buffer support must remember to reset it. The patch itself is okay, it is just something to keep in-mind when reviewing/changing drivers. -- Best regards, Jesper Dangaard Brouer MSc.CS, Principal Kernel Engineer at Red Hat LinkedIn: http://www.linkedin.com/in/brouer