On Sun, 14 Jun 2020 09:11:28 +0200 Sven Auhagen <sven.auha...@voleatech.de> wrote:
> The packet header prefetch is at an offset > now. Correct the prefetch address. > > Signed-off-by: Sven Auhagen <sven.auha...@voleatech.de> > --- > drivers/net/ethernet/marvell/mvneta.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/net/ethernet/marvell/mvneta.c > b/drivers/net/ethernet/marvell/mvneta.c > index 51889770958d..344fc5f649b4 100644 > --- a/drivers/net/ethernet/marvell/mvneta.c > +++ b/drivers/net/ethernet/marvell/mvneta.c > @@ -2229,7 +2229,7 @@ mvneta_swbm_rx_frame(struct mvneta_port *pp, > len, dma_dir); > > /* Prefetch header */ > - prefetch(data); > + prefetch(data + pp->rx_offset_correction + MVNETA_MH_SIZE); The comment does say "header", so I guess your change is correct if we are talking about the packet header. Currently this prefetch will help XDP-redirect, as it store xdp_frame in this area. > xdp->data_hard_start = data; > xdp->data = data + pp->rx_offset_correction + MVNETA_MH_SIZE; If you really need to prefetch the packet headers, it would be the same as calling prefetch(xdp->data), right? Have you benchmarked that this prefetch is a benefit? -- Best regards, Jesper Dangaard Brouer MSc.CS, Principal Kernel Engineer at Red Hat LinkedIn: http://www.linkedin.com/in/brouer
