Commit 743bbd93 authored by Maciej Fijalkowski's avatar Maciej Fijalkowski Committed by Tony Nguyen
Browse files

ice: put Rx buffers after being done with current frame 



Introduce a new helper ice_put_rx_mbuf() that will go through gathered
frags from current frame and will call ice_put_rx_buf() on them. Current
logic that was supposed to simplify and optimize the driver where we go
through a batch of all buffers processed in current NAPI instance turned
out to be broken for jumbo frames and very heavy load that was coming
from both multi-thread iperf and nginx/wrk pair between server and
client. The delay introduced by approach that we are dropping is simply
too big and we need to take the decision regarding page
recycling/releasing as quick as we can.

While at it, address an error path of ice_add_xdp_frag() - we were
missing buffer putting from day 1 there.

As a nice side effect we get rid of annoying and repetitive three-liner:

	xdp->data = NULL;
	rx_ring->first_desc = ntc;
	rx_ring->nr_frags = 0;

by embedding it within introduced routine.

Fixes: 1dc1a7e7 ("ice: Centrallize Rx buffer recycling")
Reported-and-tested-by: default avatarXu Du <xudu@redhat.com>
Reviewed-by: default avatarPrzemek Kitszel <przemyslaw.kitszel@intel.com>
Reviewed-by: default avatarSimon Horman <horms@kernel.org>
Co-developed-by: default avatarJacob Keller <jacob.e.keller@intel.com>
Signed-off-by: default avatarJacob Keller <jacob.e.keller@intel.com>
Signed-off-by: default avatarMaciej Fijalkowski <maciej.fijalkowski@intel.com>
Tested-by: Chandan Kumar Rout <chandanx.rout@intel.com> (A Contingent Worker at Intel)
Signed-off-by: default avatarTony Nguyen <anthony.l.nguyen@intel.com>
parent c2933b2b

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

+50 −29
Original line number Diff line number Diff line
@@ -1103,6 +1103,49 @@ ice_put_rx_buf(struct ice_rx_ring *rx_ring, struct ice_rx_buf *rx_buf) 
	rx_buf->page = NULL;

}



/**

 * ice_put_rx_mbuf - ice_put_rx_buf() caller, for all frame frags

 * @rx_ring: Rx ring with all the auxiliary data

 * @xdp: XDP buffer carrying linear + frags part

 * @xdp_xmit: XDP_TX/XDP_REDIRECT verdict storage

 * @ntc: a current next_to_clean value to be stored at rx_ring

 *

 * Walk through gathered fragments and satisfy internal page

 * recycle mechanism; we take here an action related to verdict

 * returned by XDP program;

 */

static void ice_put_rx_mbuf(struct ice_rx_ring *rx_ring, struct xdp_buff *xdp,

			    u32 *xdp_xmit, u32 ntc)

{

	u32 nr_frags = rx_ring->nr_frags + 1;

	u32 idx = rx_ring->first_desc;

	u32 cnt = rx_ring->count;

	struct ice_rx_buf *buf;

	int i;



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

		buf = &rx_ring->rx_buf[idx];



		if (buf->act & (ICE_XDP_TX | ICE_XDP_REDIR)) {

			ice_rx_buf_adjust_pg_offset(buf, xdp->frame_sz);

			*xdp_xmit |= buf->act;

		} else if (buf->act & ICE_XDP_CONSUMED) {

			buf->pagecnt_bias++;

		} else if (buf->act == ICE_XDP_PASS) {

			ice_rx_buf_adjust_pg_offset(buf, xdp->frame_sz);

		}



		ice_put_rx_buf(rx_ring, buf);



		if (++idx == cnt)

			idx = 0;

	}



	xdp->data = NULL;

	rx_ring->first_desc = ntc;

	rx_ring->nr_frags = 0;

}



/**

 * ice_clean_rx_irq - Clean completed descriptors from Rx ring - bounce buf

 * @rx_ring: Rx descriptor ring to transact packets on
@@ -1120,7 +1163,6 @@ int ice_clean_rx_irq(struct ice_rx_ring *rx_ring, int budget) 
	unsigned int total_rx_bytes = 0, total_rx_pkts = 0;

	unsigned int offset = rx_ring->rx_offset;

	struct xdp_buff *xdp = &rx_ring->xdp;

	u32 cached_ntc = rx_ring->first_desc;

	struct ice_tx_ring *xdp_ring = NULL;

	struct bpf_prog *xdp_prog = NULL;

	u32 ntc = rx_ring->next_to_clean;
@@ -1128,7 +1170,6 @@ int ice_clean_rx_irq(struct ice_rx_ring *rx_ring, int budget) 
	u32 xdp_xmit = 0;

	u32 cached_ntu;

	bool failure;

	u32 first;



	xdp_prog = READ_ONCE(rx_ring->xdp_prog);

	if (xdp_prog) {
@@ -1190,6 +1231,7 @@ int ice_clean_rx_irq(struct ice_rx_ring *rx_ring, int budget) 
			xdp_prepare_buff(xdp, hard_start, offset, size, !!offset);

			xdp_buff_clear_frags_flag(xdp);

		} else if (ice_add_xdp_frag(rx_ring, xdp, rx_buf, size)) {

			ice_put_rx_mbuf(rx_ring, xdp, NULL, ntc);

			break;

		}

		if (++ntc == cnt)
@@ -1205,9 +1247,8 @@ int ice_clean_rx_irq(struct ice_rx_ring *rx_ring, int budget) 
		total_rx_bytes += xdp_get_buff_len(xdp);

		total_rx_pkts++;



		xdp->data = NULL;

		rx_ring->first_desc = ntc;

		rx_ring->nr_frags = 0;

		ice_put_rx_mbuf(rx_ring, xdp, &xdp_xmit, ntc);



		continue;

construct_skb:

		if (likely(ice_ring_uses_build_skb(rx_ring)))
@@ -1221,14 +1262,11 @@ int ice_clean_rx_irq(struct ice_rx_ring *rx_ring, int budget) 
			if (unlikely(xdp_buff_has_frags(xdp)))

				ice_set_rx_bufs_act(xdp, rx_ring,

						    ICE_XDP_CONSUMED);

			xdp->data = NULL;

			rx_ring->first_desc = ntc;

			rx_ring->nr_frags = 0;

			break;

		}

		xdp->data = NULL;

		rx_ring->first_desc = ntc;

		rx_ring->nr_frags = 0;

		ice_put_rx_mbuf(rx_ring, xdp, &xdp_xmit, ntc);



		if (!skb)

			break;



		stat_err_bits = BIT(ICE_RX_FLEX_DESC_STATUS0_RXE_S);

		if (unlikely(ice_test_staterr(rx_desc->wb.status_error0,
@@ -1257,23 +1295,6 @@ int ice_clean_rx_irq(struct ice_rx_ring *rx_ring, int budget) 
		total_rx_pkts++;

	}



	first = rx_ring->first_desc;

	while (cached_ntc != first) {

		struct ice_rx_buf *buf = &rx_ring->rx_buf[cached_ntc];



		if (buf->act & (ICE_XDP_TX | ICE_XDP_REDIR)) {

			ice_rx_buf_adjust_pg_offset(buf, xdp->frame_sz);

			xdp_xmit |= buf->act;

		} else if (buf->act & ICE_XDP_CONSUMED) {

			buf->pagecnt_bias++;

		} else if (buf->act == ICE_XDP_PASS) {

			ice_rx_buf_adjust_pg_offset(buf, xdp->frame_sz);

		}



		ice_put_rx_buf(rx_ring, buf);

		if (++cached_ntc >= cnt)

			cached_ntc = 0;

	}

	rx_ring->next_to_clean = ntc;

	/* return up to cleaned_count buffers to hardware */

	failure = ice_alloc_rx_bufs(rx_ring, ICE_RX_DESC_UNUSED(rx_ring));