Commit ad07f29b authored by Alexander Lobakin's avatar Alexander Lobakin Committed by Daniel Borkmann
Browse files

ice: Micro-optimize .ndo_xdp_xmit() path 



After the recent mbuf changes, ice_xmit_xdp_ring() became a 3-liner.
It makes no sense to keep it global in a different file than its caller.
Move it just next to the sole call site and mark static. Also, it
doesn't need a full xdp_convert_frame_to_buff(). Save several cycles
and fill only the fields used by __ice_xmit_xdp_ring() later on.
Finally, since it doesn't modify @xdpf anyhow, mark the argument const
to save some more (whole -11 bytes of .text! :D).

Thanks to 1 jump less and less calcs as well, this yields as many as
6.7 Mpps per queue. `xdp.data_hard_start = xdpf` is fully intentional
again (see xdp_convert_buff_to_frame()) and just works when there are
no source device's driver issues.

Signed-off-by: default avatarAlexander Lobakin <alexandr.lobakin@intel.com>
Signed-off-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
Acked-by: default avatarMaciej Fijalkowski <maciej.fijalkowski@intel.com>
Link: https://lore.kernel.org/bpf/20230210170618.1973430-7-alexandr.lobakin@intel.com
parent 055d0920

drivers/net/ethernet/intel/ice/ice_txrx.c

+20 −1
Original line number Diff line number Diff line
@@ -605,6 +605,25 @@ ice_run_xdp(struct ice_rx_ring *rx_ring, struct xdp_buff *xdp, 
		ice_set_rx_bufs_act(xdp, rx_ring, ret);

}



/**

 * ice_xmit_xdp_ring - submit frame to XDP ring for transmission

 * @xdpf: XDP frame that will be converted to XDP buff

 * @xdp_ring: XDP ring for transmission

 */

static int ice_xmit_xdp_ring(const struct xdp_frame *xdpf,

			     struct ice_tx_ring *xdp_ring)

{

	struct xdp_buff xdp;



	xdp.data_hard_start = (void *)xdpf;

	xdp.data = xdpf->data;

	xdp.data_end = xdp.data + xdpf->len;

	xdp.frame_sz = xdpf->frame_sz;

	xdp.flags = xdpf->flags;



	return __ice_xmit_xdp_ring(&xdp, xdp_ring, true);

}



/**

 * ice_xdp_xmit - submit packets to XDP ring for transmission

 * @dev: netdev
@@ -650,7 +669,7 @@ ice_xdp_xmit(struct net_device *dev, int n, struct xdp_frame **frames, 


	tx_buf = &xdp_ring->tx_buf[xdp_ring->next_to_use];

	for (i = 0; i < n; i++) {

		struct xdp_frame *xdpf = frames[i];

		const struct xdp_frame *xdpf = frames[i];

		int err;



		err = ice_xmit_xdp_ring(xdpf, xdp_ring);

drivers/net/ethernet/intel/ice/ice_txrx_lib.c

+0 −13
Original line number Diff line number Diff line
@@ -434,19 +434,6 @@ int __ice_xmit_xdp_ring(struct xdp_buff *xdp, struct ice_tx_ring *xdp_ring, 
	return ICE_XDP_CONSUMED;

}



/**

 * ice_xmit_xdp_ring - submit frame to XDP ring for transmission

 * @xdpf: XDP frame that will be converted to XDP buff

 * @xdp_ring: XDP ring for transmission

 */

int ice_xmit_xdp_ring(struct xdp_frame *xdpf, struct ice_tx_ring *xdp_ring)

{

	struct xdp_buff xdp;



	xdp_convert_frame_to_buff(xdpf, &xdp);

	return __ice_xmit_xdp_ring(&xdp, xdp_ring, true);

}



/**

 * ice_finalize_xdp_rx - Bump XDP Tx tail and/or flush redirect map

 * @xdp_ring: XDP ring

drivers/net/ethernet/intel/ice/ice_txrx_lib.h

+0 −1
Original line number Diff line number Diff line
@@ -142,7 +142,6 @@ static inline u32 ice_set_rs_bit(const struct ice_tx_ring *xdp_ring) 


void ice_finalize_xdp_rx(struct ice_tx_ring *xdp_ring, unsigned int xdp_res, u32 first_idx);

int ice_xmit_xdp_buff(struct xdp_buff *xdp, struct ice_tx_ring *xdp_ring);

int ice_xmit_xdp_ring(struct xdp_frame *xdpf, struct ice_tx_ring *xdp_ring);

int __ice_xmit_xdp_ring(struct xdp_buff *xdp, struct ice_tx_ring *xdp_ring,

			bool frame);

void ice_release_rx_desc(struct ice_rx_ring *rx_ring, u16 val);