[PATCH net-next v4 0/3] net: atlantic: Add XDP support

[PATCH net-next v4 0/3] net: atlantic: Add XDP support

[Taehee Yoo]

This patchset is to make atlantic to support multi-buffer XDP.

The first patch implement control plane of xdp.
The aq_xdp(), callback of .xdp_bpf is added.

The second patch implements data plane of xdp.
XDP_TX, XDP_DROP, and XDP_PASS is supported.
__aq_ring_xdp_clean() is added to receive and execute xdp program.
aq_nic_xmit_xdpf() is added to send packet by XDP.

The third patch implements callback of .ndo_xdp_xmit.
aq_xdp_xmit() is added to send redirected packets and it internally
calls aq_nic_xmit_xdpf().

Memory model is MEM_TYPE_PAGE_ORDER0 so it doesn't reuse rx page when
XDP_TX, XDP_PASS, XDP_REDIRECT.

Default the maximum rx frame size is 2K.
If xdp is attached, size is changed to about 3K.
It can be reused when XDP_DROP, and XDP_ABORTED.

Atlantic driver has AQ_CFG_RX_PAGEORDER option and it will be always 0
if xdp is attached.

LRO will be disabled if XDP program supports only single buffer.

AQC chip supports 32 multi-queues and 8 vectors(irq).
There are two options.
1. under 8 cores and maximum 4 tx queues per core.
2. under 4 cores and maximum 8 tx queues per core.

Like other drivers, these tx queues can be used only for XDP_TX,
XDP_REDIRECT queue. If so, no tx_lock is needed.
But this patchset doesn't use this strategy because getting hardware tx
queue index cost is too high.
So, tx_lock is used in the aq_nic_xmit_xdpf().

single-core, single queue, 80% cpu utilization.

  30.75%  bpf_prog_xxx_xdp_prog_tx  [k] bpf_prog_xxx_xdp_prog_tx
  10.35%  [kernel]                  [k] aq_hw_read_reg <---------- here
   4.38%  [kernel]                  [k] get_page_from_freelist

single-core, 8 queues, 100% cpu utilization, half PPS.

  45.56%  [kernel]                  [k] aq_hw_read_reg <---------- here
  17.58%  bpf_prog_xxx_xdp_prog_tx  [k] bpf_prog_xxx_xdp_prog_tx
   4.72%  [kernel]                  [k] hw_atl_b0_hw_ring_rx_receive

Performance result(64 Byte)
1. XDP_TX
  a. xdp_geieric, single core
    - 2.5Mpps, 100% cpu
  b. xdp_driver, single core
    - 4.5Mpps, 80% cpu
  c. xdp_generic, 8 core(hyper thread)
    - 6.3Mpps, 5~10% cpu
  d. xdp_driver, 8 core(hyper thread)
    - 6.3Mpps, 5% cpu

2. XDP_REDIRECT
  a. xdp_generic, single core
    - 2.3Mpps
  b. xdp_driver, single core
    - 4.5Mpps

v4:
 - Fix compile warning

v3:
 - Change wrong PPS performance result 40% -> 80% in single
   core(Intel i3-12100)
 - Separate aq_nic_map_xdp() from aq_nic_map_skb()
 - Drop multi buffer packets if single buffer XDP is attached
 - Disable LRO when single buffer XDP is attached
 - Use xdp_get_{frame/buff}_len()

v2:
 - Do not use inline in C file

Taehee Yoo (3):
  net: atlantic: Implement xdp control plane
  net: atlantic: Implement xdp data plane
  net: atlantic: Implement .ndo_xdp_xmit handler

 .../net/ethernet/aquantia/atlantic/aq_cfg.h   |   1 +
 .../ethernet/aquantia/atlantic/aq_ethtool.c   |   8 +
 .../net/ethernet/aquantia/atlantic/aq_main.c  |  87 ++++
 .../net/ethernet/aquantia/atlantic/aq_main.h  |   2 +
 .../net/ethernet/aquantia/atlantic/aq_nic.c   | 137 ++++++
 .../net/ethernet/aquantia/atlantic/aq_nic.h   |   5 +
 .../net/ethernet/aquantia/atlantic/aq_ring.c  | 415 ++++++++++++++++--
 .../net/ethernet/aquantia/atlantic/aq_ring.h  |  17 +
 .../net/ethernet/aquantia/atlantic/aq_vec.c   |  23 +-
 .../net/ethernet/aquantia/atlantic/aq_vec.h   |   6 +
 .../aquantia/atlantic/hw_atl/hw_atl_a0.c      |   6 +-
 .../aquantia/atlantic/hw_atl/hw_atl_b0.c      |  10 +-
 12 files changed, 675 insertions(+), 42 deletions(-)

-- 
2.17.1

[PATCH net-next v4 1/3] net: atlantic: Implement xdp control plane

[Taehee Yoo]

aq_xdp() is a xdp setup callback function for Atlantic driver.
When XDP is attached or detached, the device will be restarted because
it uses different maximum frame sizes.
If XDP is disabled, 2K RX frame size is used and alloc_skb() is used too.
So, It can reuse the next half of that page(flip like the ixgbe).
Or, if a reference count is 1(no other user) that page can be fully reused.

   ethtool -S <interface name> | grep Page
     Queue[0] PageFlips: 0 <-- use half of page
     Queue[0] PageReuses: 7 <-- reuse full page

But if XDP is enabled, it uses 3K frame size.
So, the Flip strategy can not be applied.
And reusing a full page is possible only when XDP_DROP, XDP_ABORT.

Also, It supports xdp fragment feature.
mtu can be 16K if xdp prog supports xdp fragment.
if not, mtu can not exceed 3K - ETH_HLEN - ETH_FCS.

And a static key is added and It will be used to call the xdp_clean
handler in ->poll(). data plane implementation will be contained
the followed patch.

Signed-off-by: Taehee Yoo <ap420073@gmail.com>
---

v4:
 - No changed

v3:
 - Disable LRO when single buffer XDP is attached

v2:
 - No changed

 .../net/ethernet/aquantia/atlantic/aq_cfg.h   |  1 +
 .../net/ethernet/aquantia/atlantic/aq_main.c  | 86 +++++++++++++++++++
 .../net/ethernet/aquantia/atlantic/aq_main.h  |  2 +
 .../net/ethernet/aquantia/atlantic/aq_nic.h   |  3 +
 .../net/ethernet/aquantia/atlantic/aq_ring.c  | 57 +++++++-----
 .../net/ethernet/aquantia/atlantic/aq_ring.h  |  9 ++
 .../net/ethernet/aquantia/atlantic/aq_vec.c   | 23 +++--
 .../net/ethernet/aquantia/atlantic/aq_vec.h   |  6 ++
 .../aquantia/atlantic/hw_atl/hw_atl_a0.c      |  6 +-
 .../aquantia/atlantic/hw_atl/hw_atl_b0.c      | 10 +--
 10 files changed, 169 insertions(+), 34 deletions(-)

diff --git a/drivers/net/ethernet/aquantia/atlantic/aq_cfg.h b/drivers/net/ethernet/aquantia/atlantic/aq_cfg.h
index 52b9833fda99..22575adedf66 100644
--- a/drivers/net/ethernet/aquantia/atlantic/aq_cfg.h
+++ b/drivers/net/ethernet/aquantia/atlantic/aq_cfg.h
@@ -32,6 +32,7 @@
 
 #define AQ_CFG_TX_FRAME_MAX  (16U * 1024U)
 #define AQ_CFG_RX_FRAME_MAX  (2U * 1024U)
+#define AQ_CFG_XDP_FRAME_MAX  (3U * 1024U)
 
 #define AQ_CFG_TX_CLEAN_BUDGET 256U
 
diff --git a/drivers/net/ethernet/aquantia/atlantic/aq_main.c b/drivers/net/ethernet/aquantia/atlantic/aq_main.c
index e65ce7199dac..43012648a351 100644
--- a/drivers/net/ethernet/aquantia/atlantic/aq_main.c
+++ b/drivers/net/ethernet/aquantia/atlantic/aq_main.c
@@ -14,17 +14,22 @@
 #include "aq_ptp.h"
 #include "aq_filters.h"
 #include "aq_hw_utils.h"
+#include "aq_vec.h"
 
 #include <linux/netdevice.h>
 #include <linux/module.h>
 #include <linux/ip.h>
 #include <linux/udp.h>
 #include <net/pkt_cls.h>
+#include <linux/filter.h>
 
 MODULE_LICENSE("GPL v2");
 MODULE_AUTHOR(AQ_CFG_DRV_AUTHOR);
 MODULE_DESCRIPTION(AQ_CFG_DRV_DESC);
 
+DEFINE_STATIC_KEY_FALSE(aq_xdp_locking_key);
+EXPORT_SYMBOL(aq_xdp_locking_key);
+
 static const char aq_ndev_driver_name[] = AQ_CFG_DRV_NAME;
 
 static const struct net_device_ops aq_ndev_ops;
@@ -126,9 +131,19 @@ static netdev_tx_t aq_ndev_start_xmit(struct sk_buff *skb, struct net_device *nd
 
 static int aq_ndev_change_mtu(struct net_device *ndev, int new_mtu)
 {
+	int new_frame_size = new_mtu + ETH_HLEN + ETH_FCS_LEN;
 	struct aq_nic_s *aq_nic = netdev_priv(ndev);
+	struct bpf_prog *prog;
 	int err;
 
+	prog = READ_ONCE(aq_nic->xdp_prog);
+	if (prog && !prog->aux->xdp_has_frags &&
+	    new_frame_size > AQ_CFG_XDP_FRAME_MAX) {
+		netdev_err(ndev, "Illegal MTU %d for XDP prog without frags\n",
+			   ndev->mtu);
+		return -EOPNOTSUPP;
+	}
+
 	err = aq_nic_set_mtu(aq_nic, new_mtu + ETH_HLEN);
 
 	if (err < 0)
@@ -204,6 +219,25 @@ static int aq_ndev_set_features(struct net_device *ndev,
 	return err;
 }
 
+static netdev_features_t aq_ndev_fix_features(struct net_device *ndev,
+					      netdev_features_t features)
+{
+	struct aq_nic_s *aq_nic = netdev_priv(ndev);
+	struct bpf_prog *prog;
+
+	if (!(features & NETIF_F_RXCSUM))
+		features &= ~NETIF_F_LRO;
+
+	prog = READ_ONCE(aq_nic->xdp_prog);
+	if (prog && !prog->aux->xdp_has_frags &&
+	    aq_nic->xdp_prog && features & NETIF_F_LRO) {
+		netdev_err(ndev, "LRO is not supported with single buffer XDP, disabling\n");
+		features &= ~NETIF_F_LRO;
+	}
+
+	return features;
+}
+
 static int aq_ndev_set_mac_address(struct net_device *ndev, void *addr)
 {
 	struct aq_nic_s *aq_nic = netdev_priv(ndev);
@@ -410,6 +444,56 @@ static int aq_ndo_setup_tc(struct net_device *dev, enum tc_setup_type type,
 				      mqprio->qopt.prio_tc_map);
 }
 
+static int aq_xdp_setup(struct net_device *ndev, struct bpf_prog *prog,
+			struct netlink_ext_ack *extack)
+{
+	bool need_update, running = netif_running(ndev);
+	struct aq_nic_s *aq_nic = netdev_priv(ndev);
+	struct bpf_prog *old_prog;
+
+	if (prog && !prog->aux->xdp_has_frags) {
+		if (ndev->mtu > AQ_CFG_XDP_FRAME_MAX) {
+			NL_SET_ERR_MSG_MOD(extack,
+					   "prog does not support XDP frags");
+			return -EOPNOTSUPP;
+		}
+
+		if (prog && ndev->features & NETIF_F_LRO) {
+			netdev_err(ndev,
+				   "LRO is not supported with single buffer XDP, disabling\n");
+			ndev->features &= ~NETIF_F_LRO;
+		}
+	}
+
+	need_update = !!aq_nic->xdp_prog != !!prog;
+	if (running && need_update)
+		aq_ndev_close(ndev);
+
+	old_prog = xchg(&aq_nic->xdp_prog, prog);
+	if (old_prog)
+		bpf_prog_put(old_prog);
+
+	if (!old_prog && prog)
+		static_branch_inc(&aq_xdp_locking_key);
+	else if (old_prog && !prog)
+		static_branch_dec(&aq_xdp_locking_key);
+
+	if (running && need_update)
+		return aq_ndev_open(ndev);
+
+	return 0;
+}
+
+static int aq_xdp(struct net_device *dev, struct netdev_bpf *xdp)
+{
+	switch (xdp->command) {
+	case XDP_SETUP_PROG:
+		return aq_xdp_setup(dev, xdp->prog, xdp->extack);
+	default:
+		return -EINVAL;
+	}
+}
+
 static const struct net_device_ops aq_ndev_ops = {
 	.ndo_open = aq_ndev_open,
 	.ndo_stop = aq_ndev_close,
@@ -418,10 +502,12 @@ static const struct net_device_ops aq_ndev_ops = {
 	.ndo_change_mtu = aq_ndev_change_mtu,
 	.ndo_set_mac_address = aq_ndev_set_mac_address,
 	.ndo_set_features = aq_ndev_set_features,
+	.ndo_fix_features = aq_ndev_fix_features,
 	.ndo_eth_ioctl = aq_ndev_ioctl,
 	.ndo_vlan_rx_add_vid = aq_ndo_vlan_rx_add_vid,
 	.ndo_vlan_rx_kill_vid = aq_ndo_vlan_rx_kill_vid,
 	.ndo_setup_tc = aq_ndo_setup_tc,
+	.ndo_bpf = aq_xdp,
 };
 
 static int __init aq_ndev_init_module(void)
diff --git a/drivers/net/ethernet/aquantia/atlantic/aq_main.h b/drivers/net/ethernet/aquantia/atlantic/aq_main.h
index a5a624b9ce73..99870865f66d 100644
--- a/drivers/net/ethernet/aquantia/atlantic/aq_main.h
+++ b/drivers/net/ethernet/aquantia/atlantic/aq_main.h
@@ -12,6 +12,8 @@
 #include "aq_common.h"
 #include "aq_nic.h"
 
+DECLARE_STATIC_KEY_FALSE(aq_xdp_locking_key);
+
 void aq_ndev_schedule_work(struct work_struct *work);
 struct net_device *aq_ndev_alloc(void);
 
diff --git a/drivers/net/ethernet/aquantia/atlantic/aq_nic.h b/drivers/net/ethernet/aquantia/atlantic/aq_nic.h
index 1a7148041e3d..47123baabd5e 100644
--- a/drivers/net/ethernet/aquantia/atlantic/aq_nic.h
+++ b/drivers/net/ethernet/aquantia/atlantic/aq_nic.h
@@ -11,6 +11,8 @@
 #define AQ_NIC_H
 
 #include <linux/ethtool.h>
+#include <net/xdp.h>
+#include <linux/bpf.h>
 
 #include "aq_common.h"
 #include "aq_rss.h"
@@ -128,6 +130,7 @@ struct aq_nic_s {
 	struct aq_vec_s *aq_vec[AQ_CFG_VECS_MAX];
 	struct aq_ring_s *aq_ring_tx[AQ_HW_QUEUES_MAX];
 	struct aq_hw_s *aq_hw;
+	struct bpf_prog *xdp_prog;
 	struct net_device *ndev;
 	unsigned int aq_vecs;
 	unsigned int packet_filter;
diff --git a/drivers/net/ethernet/aquantia/atlantic/aq_ring.c b/drivers/net/ethernet/aquantia/atlantic/aq_ring.c
index 77e76c9efd32..b261283641a7 100644
--- a/drivers/net/ethernet/aquantia/atlantic/aq_ring.c
+++ b/drivers/net/ethernet/aquantia/atlantic/aq_ring.c
@@ -7,12 +7,16 @@
 
 /* File aq_ring.c: Definition of functions for Rx/Tx rings. */
 
-#include "aq_ring.h"
 #include "aq_nic.h"
 #include "aq_hw.h"
 #include "aq_hw_utils.h"
 #include "aq_ptp.h"
+#include "aq_vec.h"
+#include "aq_main.h"
 
+#include <net/xdp.h>
+#include <linux/filter.h>
+#include <linux/bpf_trace.h>
 #include <linux/netdevice.h>
 #include <linux/etherdevice.h>
 
@@ -27,9 +31,10 @@ static inline void aq_free_rxpage(struct aq_rxpage *rxpage, struct device *dev)
 	rxpage->page = NULL;
 }
 
-static int aq_get_rxpage(struct aq_rxpage *rxpage, unsigned int order,
-			 struct device *dev)
+static int aq_get_rxpage(struct aq_rxpage *rxpage, struct aq_ring_s *rx_ring)
 {
+	struct device *dev = aq_nic_get_dev(rx_ring->aq_nic);
+	unsigned int order = rx_ring->page_order;
 	struct page *page;
 	int ret = -ENOMEM;
 	dma_addr_t daddr;
@@ -47,7 +52,7 @@ static int aq_get_rxpage(struct aq_rxpage *rxpage, unsigned int order,
 	rxpage->page = page;
 	rxpage->daddr = daddr;
 	rxpage->order = order;
-	rxpage->pg_off = 0;
+	rxpage->pg_off = rx_ring->page_offset;
 
 	return 0;
 
@@ -58,21 +63,24 @@ static int aq_get_rxpage(struct aq_rxpage *rxpage, unsigned int order,
 	return ret;
 }
 
-static int aq_get_rxpages(struct aq_ring_s *self, struct aq_ring_buff_s *rxbuf,
-			  int order)
+static int aq_get_rxpages(struct aq_ring_s *self, struct aq_ring_buff_s *rxbuf)
 {
+	unsigned int order = self->page_order;
+	u16 page_offset = self->page_offset;
+	u16 frame_max = self->frame_max;
 	int ret;
 
 	if (rxbuf->rxdata.page) {
 		/* One means ring is the only user and can reuse */
 		if (page_ref_count(rxbuf->rxdata.page) > 1) {
 			/* Try reuse buffer */
-			rxbuf->rxdata.pg_off += AQ_CFG_RX_FRAME_MAX;
-			if (rxbuf->rxdata.pg_off + AQ_CFG_RX_FRAME_MAX <=
+			rxbuf->rxdata.pg_off += frame_max + page_offset;
+			if (rxbuf->rxdata.pg_off + frame_max <=
 				(PAGE_SIZE << order)) {
 				u64_stats_update_begin(&self->stats.rx.syncp);
 				self->stats.rx.pg_flips++;
 				u64_stats_update_end(&self->stats.rx.syncp);
+
 			} else {
 				/* Buffer exhausted. We have other users and
 				 * should release this page and realloc
@@ -84,7 +92,7 @@ static int aq_get_rxpages(struct aq_ring_s *self, struct aq_ring_buff_s *rxbuf,
 				u64_stats_update_end(&self->stats.rx.syncp);
 			}
 		} else {
-			rxbuf->rxdata.pg_off = 0;
+			rxbuf->rxdata.pg_off = page_offset;
 			u64_stats_update_begin(&self->stats.rx.syncp);
 			self->stats.rx.pg_reuses++;
 			u64_stats_update_end(&self->stats.rx.syncp);
@@ -92,8 +100,7 @@ static int aq_get_rxpages(struct aq_ring_s *self, struct aq_ring_buff_s *rxbuf,
 	}
 
 	if (!rxbuf->rxdata.page) {
-		ret = aq_get_rxpage(&rxbuf->rxdata, order,
-				    aq_nic_get_dev(self->aq_nic));
+		ret = aq_get_rxpage(&rxbuf->rxdata, self);
 		if (ret) {
 			u64_stats_update_begin(&self->stats.rx.syncp);
 			self->stats.rx.alloc_fails++;
@@ -117,6 +124,7 @@ static struct aq_ring_s *aq_ring_alloc(struct aq_ring_s *self,
 		err = -ENOMEM;
 		goto err_exit;
 	}
+
 	self->dx_ring = dma_alloc_coherent(aq_nic_get_dev(aq_nic),
 					   self->size * self->dx_size,
 					   &self->dx_ring_pa, GFP_KERNEL);
@@ -172,11 +180,21 @@ struct aq_ring_s *aq_ring_rx_alloc(struct aq_ring_s *self,
 	self->idx = idx;
 	self->size = aq_nic_cfg->rxds;
 	self->dx_size = aq_nic_cfg->aq_hw_caps->rxd_size;
-	self->page_order = fls(AQ_CFG_RX_FRAME_MAX / PAGE_SIZE +
-			       (AQ_CFG_RX_FRAME_MAX % PAGE_SIZE ? 1 : 0)) - 1;
+	self->xdp_prog = aq_nic->xdp_prog;
 
-	if (aq_nic_cfg->rxpageorder > self->page_order)
-		self->page_order = aq_nic_cfg->rxpageorder;
+	/* Only order-0 is allowed if XDP is enabled */
+	if (READ_ONCE(self->xdp_prog)) {
+		self->page_offset = AQ_XDP_HEADROOM;
+		self->page_order = 0;
+		self->frame_max = AQ_CFG_XDP_FRAME_MAX;
+	} else {
+		self->page_offset = 0;
+		self->frame_max = AQ_CFG_RX_FRAME_MAX;
+		self->page_order = fls(self->frame_max / PAGE_SIZE +
+				       (self->frame_max % PAGE_SIZE ? 1 : 0)) - 1;
+		if (aq_nic_cfg->rxpageorder > self->page_order)
+			self->page_order = aq_nic_cfg->rxpageorder;
+	}
 
 	self = aq_ring_alloc(self, aq_nic);
 	if (!self) {
@@ -449,7 +467,7 @@ int aq_ring_rx_clean(struct aq_ring_s *self,
 			skb_add_rx_frag(skb, 0, buff->rxdata.page,
 					buff->rxdata.pg_off + hdr_len,
 					buff->len - hdr_len,
-					AQ_CFG_RX_FRAME_MAX);
+					self->frame_max);
 			page_ref_inc(buff->rxdata.page);
 		}
 
@@ -469,7 +487,7 @@ int aq_ring_rx_clean(struct aq_ring_s *self,
 						buff_->rxdata.page,
 						buff_->rxdata.pg_off,
 						buff_->len,
-						AQ_CFG_RX_FRAME_MAX);
+						self->frame_max);
 				page_ref_inc(buff_->rxdata.page);
 				buff_->is_cleaned = 1;
 
@@ -529,7 +547,6 @@ void aq_ring_hwts_rx_clean(struct aq_ring_s *self, struct aq_nic_s *aq_nic)
 
 int aq_ring_rx_fill(struct aq_ring_s *self)
 {
-	unsigned int page_order = self->page_order;
 	struct aq_ring_buff_s *buff = NULL;
 	int err = 0;
 	int i = 0;
@@ -543,9 +560,9 @@ int aq_ring_rx_fill(struct aq_ring_s *self)
 		buff = &self->buff_ring[self->sw_tail];
 
 		buff->flags = 0U;
-		buff->len = AQ_CFG_RX_FRAME_MAX;
+		buff->len = self->frame_max;
 
-		err = aq_get_rxpages(self, buff, page_order);
+		err = aq_get_rxpages(self, buff);
 		if (err)
 			goto err_exit;
 
diff --git a/drivers/net/ethernet/aquantia/atlantic/aq_ring.h b/drivers/net/ethernet/aquantia/atlantic/aq_ring.h
index 93659e58f1ce..168002657629 100644
--- a/drivers/net/ethernet/aquantia/atlantic/aq_ring.h
+++ b/drivers/net/ethernet/aquantia/atlantic/aq_ring.h
@@ -11,6 +11,9 @@
 #define AQ_RING_H
 
 #include "aq_common.h"
+#include "aq_vec.h"
+
+#define AQ_XDP_HEADROOM		ALIGN(max(NET_SKB_PAD, XDP_PACKET_HEADROOM), 8)
 
 struct page;
 struct aq_nic_cfg_s;
@@ -51,6 +54,7 @@ struct __packed aq_ring_buff_s {
 		struct {
 			dma_addr_t pa_eop;
 			struct sk_buff *skb;
+			struct xdp_frame *xdpf;
 		};
 		/* TxC */
 		struct {
@@ -133,9 +137,13 @@ struct aq_ring_s {
 	unsigned int dx_size;	/* TX or RX descriptor size,  */
 				/* stored here for fater math */
 	unsigned int page_order;
+	u16 page_offset;
+	u16 frame_max;
 	union aq_ring_stats_s stats;
 	dma_addr_t dx_ring_pa;
+	struct bpf_prog *xdp_prog;
 	enum atl_ring_type ring_type;
+	struct xdp_rxq_info xdp_rxq;
 };
 
 struct aq_ring_param_s {
@@ -175,6 +183,7 @@ struct aq_ring_s *aq_ring_rx_alloc(struct aq_ring_s *self,
 				   struct aq_nic_s *aq_nic,
 				   unsigned int idx,
 				   struct aq_nic_cfg_s *aq_nic_cfg);
+
 int aq_ring_init(struct aq_ring_s *self, const enum atl_ring_type ring_type);
 void aq_ring_rx_deinit(struct aq_ring_s *self);
 void aq_ring_free(struct aq_ring_s *self);
diff --git a/drivers/net/ethernet/aquantia/atlantic/aq_vec.c b/drivers/net/ethernet/aquantia/atlantic/aq_vec.c
index f4774cf051c9..9657adcdd3c4 100644
--- a/drivers/net/ethernet/aquantia/atlantic/aq_vec.c
+++ b/drivers/net/ethernet/aquantia/atlantic/aq_vec.c
@@ -10,11 +10,6 @@
  */
 
 #include "aq_vec.h"
-#include "aq_nic.h"
-#include "aq_ring.h"
-#include "aq_hw.h"
-
-#include <linux/netdevice.h>
 
 struct aq_vec_s {
 	const struct aq_hw_ops *aq_hw_ops;
@@ -153,9 +148,23 @@ int aq_vec_ring_alloc(struct aq_vec_s *self, struct aq_nic_s *aq_nic,
 
 		aq_nic_set_tx_ring(aq_nic, idx_ring, ring);
 
+		if (xdp_rxq_info_reg(&self->ring[i][AQ_VEC_RX_ID].xdp_rxq,
+				     aq_nic->ndev, idx,
+				     self->napi.napi_id) < 0) {
+			err = -ENOMEM;
+			goto err_exit;
+		}
+		if (xdp_rxq_info_reg_mem_model(&self->ring[i][AQ_VEC_RX_ID].xdp_rxq,
+					       MEM_TYPE_PAGE_ORDER0, NULL) < 0) {
+			xdp_rxq_info_unreg(&self->ring[i][AQ_VEC_RX_ID].xdp_rxq);
+			err = -ENOMEM;
+			goto err_exit;
+		}
+
 		ring = aq_ring_rx_alloc(&self->ring[i][AQ_VEC_RX_ID], aq_nic,
 					idx_ring, aq_nic_cfg);
 		if (!ring) {
+			xdp_rxq_info_unreg(&self->ring[i][AQ_VEC_RX_ID].xdp_rxq);
 			err = -ENOMEM;
 			goto err_exit;
 		}
@@ -300,8 +309,10 @@ void aq_vec_ring_free(struct aq_vec_s *self)
 	for (i = 0U, ring = self->ring[0];
 		self->tx_rings > i; ++i, ring = self->ring[i]) {
 		aq_ring_free(&ring[AQ_VEC_TX_ID]);
-		if (i < self->rx_rings)
+		if (i < self->rx_rings) {
+			xdp_rxq_info_unreg(&ring[AQ_VEC_RX_ID].xdp_rxq);
 			aq_ring_free(&ring[AQ_VEC_RX_ID]);
+		}
 	}
 
 	self->tx_rings = 0;
diff --git a/drivers/net/ethernet/aquantia/atlantic/aq_vec.h b/drivers/net/ethernet/aquantia/atlantic/aq_vec.h
index 567f3d4b79a2..78fac609b71d 100644
--- a/drivers/net/ethernet/aquantia/atlantic/aq_vec.h
+++ b/drivers/net/ethernet/aquantia/atlantic/aq_vec.h
@@ -13,7 +13,13 @@
 #define AQ_VEC_H
 
 #include "aq_common.h"
+#include "aq_nic.h"
+#include "aq_ring.h"
+#include "aq_hw.h"
+
 #include <linux/irqreturn.h>
+#include <linux/filter.h>
+#include <linux/netdevice.h>
 
 struct aq_hw_s;
 struct aq_hw_ops;
diff --git a/drivers/net/ethernet/aquantia/atlantic/hw_atl/hw_atl_a0.c b/drivers/net/ethernet/aquantia/atlantic/hw_atl/hw_atl_a0.c
index 4625ccb79499..9dfd68f0fda9 100644
--- a/drivers/net/ethernet/aquantia/atlantic/hw_atl/hw_atl_a0.c
+++ b/drivers/net/ethernet/aquantia/atlantic/hw_atl/hw_atl_a0.c
@@ -531,7 +531,7 @@ static int hw_atl_a0_hw_ring_rx_init(struct aq_hw_s *self,
 	hw_atl_rdm_rx_desc_len_set(self, aq_ring->size / 8U, aq_ring->idx);
 
 	hw_atl_rdm_rx_desc_data_buff_size_set(self,
-					      AQ_CFG_RX_FRAME_MAX / 1024U,
+					      aq_ring->frame_max / 1024U,
 					      aq_ring->idx);
 
 	hw_atl_rdm_rx_desc_head_buff_size_set(self, 0U, aq_ring->idx);
@@ -706,9 +706,9 @@ static int hw_atl_a0_hw_ring_rx_receive(struct aq_hw_s *self,
 
 			if (HW_ATL_A0_RXD_WB_STAT2_EOP & rxd_wb->status) {
 				buff->len = rxd_wb->pkt_len %
-					AQ_CFG_RX_FRAME_MAX;
+					    ring->frame_max;
 				buff->len = buff->len ?
-					buff->len : AQ_CFG_RX_FRAME_MAX;
+					buff->len : ring->frame_max;
 				buff->next = 0U;
 				buff->is_eop = 1U;
 			} else {
diff --git a/drivers/net/ethernet/aquantia/atlantic/hw_atl/hw_atl_b0.c b/drivers/net/ethernet/aquantia/atlantic/hw_atl/hw_atl_b0.c
index d875ce3ec759..1cf177561aad 100644
--- a/drivers/net/ethernet/aquantia/atlantic/hw_atl/hw_atl_b0.c
+++ b/drivers/net/ethernet/aquantia/atlantic/hw_atl/hw_atl_b0.c
@@ -766,7 +766,7 @@ int hw_atl_b0_hw_ring_rx_init(struct aq_hw_s *self, struct aq_ring_s *aq_ring,
 	hw_atl_rdm_rx_desc_len_set(self, aq_ring->size / 8U, aq_ring->idx);
 
 	hw_atl_rdm_rx_desc_data_buff_size_set(self,
-					      AQ_CFG_RX_FRAME_MAX / 1024U,
+					      aq_ring->frame_max / 1024U,
 				       aq_ring->idx);
 
 	hw_atl_rdm_rx_desc_head_buff_size_set(self, 0U, aq_ring->idx);
@@ -969,15 +969,15 @@ int hw_atl_b0_hw_ring_rx_receive(struct aq_hw_s *self, struct aq_ring_s *ring)
 				  rxd_wb->status);
 		if (HW_ATL_B0_RXD_WB_STAT2_EOP & rxd_wb->status) {
 			buff->len = rxd_wb->pkt_len %
-				AQ_CFG_RX_FRAME_MAX;
+				    ring->frame_max;
 			buff->len = buff->len ?
-				buff->len : AQ_CFG_RX_FRAME_MAX;
+				buff->len : ring->frame_max;
 			buff->next = 0U;
 			buff->is_eop = 1U;
 		} else {
 			buff->len =
-				rxd_wb->pkt_len > AQ_CFG_RX_FRAME_MAX ?
-				AQ_CFG_RX_FRAME_MAX : rxd_wb->pkt_len;
+				rxd_wb->pkt_len > ring->frame_max ?
+				ring->frame_max : rxd_wb->pkt_len;
 
 			if (buff->is_lro) {
 				/* LRO */
-- 
2.17.1

[PATCH net-next v4 2/3] net: atlantic: Implement xdp data plane

[Taehee Yoo]

It supports XDP_PASS, XDP_DROP and multi buffer.

The new function aq_nic_xmit_xdpf() is used to send packet with
xdp_frame and internally it calls aq_nic_map_xdp().

AQC chip supports 32 multi-queues and 8 vectors(irq).
there are two option
1. under 8 cores and 4 tx queues per core.
2. under 4 cores and 8 tx queues per core.

Like ixgbe, these tx queues can be used only for XDP_TX, XDP_REDIRECT
queue. If so, no tx_lock is needed.
But this patchset doesn't use this strategy because getting hardware tx
queue index cost is too high.
So, tx_lock is used in the aq_nic_xmit_xdpf().

single-core, single queue, 80% cpu utilization.

  30.75%  bpf_prog_xxx_xdp_prog_tx  [k] bpf_prog_xxx_xdp_prog_tx
  10.35%  [kernel]                  [k] aq_hw_read_reg <---------- here
   4.38%  [kernel]                  [k] get_page_from_freelist

single-core, 8 queues, 100% cpu utilization, half PPS.

  45.56%  [kernel]                  [k] aq_hw_read_reg <---------- here
  17.58%  bpf_prog_xxx_xdp_prog_tx  [k] bpf_prog_xxx_xdp_prog_tx
   4.72%  [kernel]                  [k] hw_atl_b0_hw_ring_rx_receive

The new function __aq_ring_xdp_clean() is a xdp rx handler and this is
called only when XDP is attached.

Signed-off-by: Taehee Yoo <ap420073@gmail.com>
---

v4:
 - Fix compile warning

v3:
 - Change wrong PPS performance result 40% -> 80% in single
   core(Intel i3-12100)
 - Separate aq_nic_map_xdp() from aq_nic_map_skb()
 - Drop multi buffer packets if single buffer XDP is attached
 - Use xdp_get_{frame/buff}_len()

v2:
 - Do not use inline in C file

 .../ethernet/aquantia/atlantic/aq_ethtool.c   |   8 +
 .../net/ethernet/aquantia/atlantic/aq_nic.c   | 137 +++++++
 .../net/ethernet/aquantia/atlantic/aq_nic.h   |   2 +
 .../net/ethernet/aquantia/atlantic/aq_ring.c  | 335 +++++++++++++++++-
 .../net/ethernet/aquantia/atlantic/aq_ring.h  |   6 +
 5 files changed, 480 insertions(+), 8 deletions(-)

diff --git a/drivers/net/ethernet/aquantia/atlantic/aq_ethtool.c b/drivers/net/ethernet/aquantia/atlantic/aq_ethtool.c
index a418238f6309..b33979bdfde0 100644
--- a/drivers/net/ethernet/aquantia/atlantic/aq_ethtool.c
+++ b/drivers/net/ethernet/aquantia/atlantic/aq_ethtool.c
@@ -97,6 +97,14 @@ static const char * const aq_ethtool_queue_rx_stat_names[] = {
 	"%sQueue[%d] AllocFails",
 	"%sQueue[%d] SkbAllocFails",
 	"%sQueue[%d] Polls",
+	"%sQueue[%d] PageFlips",
+	"%sQueue[%d] PageReuses",
+	"%sQueue[%d] XdpAbort",
+	"%sQueue[%d] XdpDrop",
+	"%sQueue[%d] XdpPass",
+	"%sQueue[%d] XdpTx",
+	"%sQueue[%d] XdpInvalid",
+	"%sQueue[%d] XdpRedirect",
 };
 
 static const char * const aq_ethtool_queue_tx_stat_names[] = {
diff --git a/drivers/net/ethernet/aquantia/atlantic/aq_nic.c b/drivers/net/ethernet/aquantia/atlantic/aq_nic.c
index 33f1a1377588..37110d51e7e3 100644
--- a/drivers/net/ethernet/aquantia/atlantic/aq_nic.c
+++ b/drivers/net/ethernet/aquantia/atlantic/aq_nic.c
@@ -569,6 +569,104 @@ int aq_nic_start(struct aq_nic_s *self)
 	return err;
 }
 
+static unsigned int aq_nic_map_xdp(struct aq_nic_s *self,
+				   struct xdp_frame *xdpf,
+				   struct aq_ring_s *ring)
+{
+	struct device *dev = aq_nic_get_dev(self);
+	struct aq_ring_buff_s *first = NULL;
+	unsigned int dx = ring->sw_tail;
+	struct aq_ring_buff_s *dx_buff;
+	struct skb_shared_info *sinfo;
+	unsigned int frag_count = 0U;
+	unsigned int nr_frags = 0U;
+	unsigned int ret = 0U;
+	u16 total_len;
+
+	dx_buff = &ring->buff_ring[dx];
+	dx_buff->flags = 0U;
+
+	sinfo = xdp_get_shared_info_from_frame(xdpf);
+	total_len = xdpf->len;
+	dx_buff->len = total_len;
+	if (xdp_frame_has_frags(xdpf)) {
+		nr_frags = sinfo->nr_frags;
+		total_len += sinfo->xdp_frags_size;
+	}
+	dx_buff->pa = dma_map_single(dev, xdpf->data, dx_buff->len,
+				     DMA_TO_DEVICE);
+
+	if (unlikely(dma_mapping_error(dev, dx_buff->pa)))
+		goto exit;
+
+	first = dx_buff;
+	dx_buff->len_pkt = total_len;
+	dx_buff->is_sop = 1U;
+	dx_buff->is_mapped = 1U;
+	++ret;
+
+	for (; nr_frags--; ++frag_count) {
+		skb_frag_t *frag = &sinfo->frags[frag_count];
+		unsigned int frag_len = skb_frag_size(frag);
+		unsigned int buff_offset = 0U;
+		unsigned int buff_size = 0U;
+		dma_addr_t frag_pa;
+
+		while (frag_len) {
+			if (frag_len > AQ_CFG_TX_FRAME_MAX)
+				buff_size = AQ_CFG_TX_FRAME_MAX;
+			else
+				buff_size = frag_len;
+
+			frag_pa = skb_frag_dma_map(dev, frag, buff_offset,
+						   buff_size, DMA_TO_DEVICE);
+
+			if (unlikely(dma_mapping_error(dev, frag_pa)))
+				goto mapping_error;
+
+			dx = aq_ring_next_dx(ring, dx);
+			dx_buff = &ring->buff_ring[dx];
+
+			dx_buff->flags = 0U;
+			dx_buff->len = buff_size;
+			dx_buff->pa = frag_pa;
+			dx_buff->is_mapped = 1U;
+			dx_buff->eop_index = 0xffffU;
+
+			frag_len -= buff_size;
+			buff_offset += buff_size;
+
+			++ret;
+		}
+	}
+
+	first->eop_index = dx;
+	dx_buff->is_eop = 1U;
+	dx_buff->skb = NULL;
+	dx_buff->xdpf = xdpf;
+	goto exit;
+
+mapping_error:
+	for (dx = ring->sw_tail;
+	     ret > 0;
+	     --ret, dx = aq_ring_next_dx(ring, dx)) {
+		dx_buff = &ring->buff_ring[dx];
+
+		if (!(dx_buff->is_gso_tcp || dx_buff->is_gso_udp) &&
+		    !dx_buff->is_vlan && dx_buff->pa) {
+			if (unlikely(dx_buff->is_sop))
+				dma_unmap_single(dev, dx_buff->pa, dx_buff->len,
+						 DMA_TO_DEVICE);
+			else
+				dma_unmap_page(dev, dx_buff->pa, dx_buff->len,
+					       DMA_TO_DEVICE);
+		}
+	}
+
+exit:
+	return ret;
+}
+
 unsigned int aq_nic_map_skb(struct aq_nic_s *self, struct sk_buff *skb,
 			    struct aq_ring_s *ring)
 {
@@ -697,6 +795,7 @@ unsigned int aq_nic_map_skb(struct aq_nic_s *self, struct sk_buff *skb,
 	first->eop_index = dx;
 	dx_buff->is_eop = 1U;
 	dx_buff->skb = skb;
+	dx_buff->xdpf = NULL;
 	goto exit;
 
 mapping_error:
@@ -725,6 +824,44 @@ unsigned int aq_nic_map_skb(struct aq_nic_s *self, struct sk_buff *skb,
 	return ret;
 }
 
+int aq_nic_xmit_xdpf(struct aq_nic_s *aq_nic, struct aq_ring_s *tx_ring,
+		     struct xdp_frame *xdpf)
+{
+	u16 queue_index = AQ_NIC_RING2QMAP(aq_nic, tx_ring->idx);
+	struct net_device *ndev = aq_nic_get_ndev(aq_nic);
+	struct skb_shared_info *sinfo;
+	int cpu = smp_processor_id();
+	int err = NETDEV_TX_BUSY;
+	struct netdev_queue *nq;
+	unsigned int frags = 1;
+
+	if (xdp_frame_has_frags(xdpf)) {
+		sinfo = xdp_get_shared_info_from_frame(xdpf);
+		frags += sinfo->nr_frags;
+	}
+
+	if (frags > AQ_CFG_SKB_FRAGS_MAX)
+		return err;
+
+	nq = netdev_get_tx_queue(ndev, tx_ring->idx);
+	__netif_tx_lock(nq, cpu);
+
+	aq_ring_update_queue_state(tx_ring);
+
+	/* Above status update may stop the queue. Check this. */
+	if (__netif_subqueue_stopped(aq_nic_get_ndev(aq_nic), queue_index))
+		goto out;
+
+	frags = aq_nic_map_xdp(aq_nic, xdpf, tx_ring);
+	if (likely(frags))
+		err = aq_nic->aq_hw_ops->hw_ring_tx_xmit(aq_nic->aq_hw, tx_ring,
+							 frags);
+out:
+	__netif_tx_unlock(nq);
+
+	return err;
+}
+
 int aq_nic_xmit(struct aq_nic_s *self, struct sk_buff *skb)
 {
 	struct aq_nic_cfg_s *cfg = aq_nic_get_cfg(self);
diff --git a/drivers/net/ethernet/aquantia/atlantic/aq_nic.h b/drivers/net/ethernet/aquantia/atlantic/aq_nic.h
index 47123baabd5e..935ba889bd9a 100644
--- a/drivers/net/ethernet/aquantia/atlantic/aq_nic.h
+++ b/drivers/net/ethernet/aquantia/atlantic/aq_nic.h
@@ -180,6 +180,8 @@ void aq_nic_ndev_free(struct aq_nic_s *self);
 int aq_nic_start(struct aq_nic_s *self);
 unsigned int aq_nic_map_skb(struct aq_nic_s *self, struct sk_buff *skb,
 			    struct aq_ring_s *ring);
+int aq_nic_xmit_xdpf(struct aq_nic_s *aq_nic, struct aq_ring_s *tx_ring,
+		     struct xdp_frame *xdpf);
 int aq_nic_xmit(struct aq_nic_s *self, struct sk_buff *skb);
 int aq_nic_get_regs(struct aq_nic_s *self, struct ethtool_regs *regs, void *p);
 int aq_nic_get_regs_count(struct aq_nic_s *self);
diff --git a/drivers/net/ethernet/aquantia/atlantic/aq_ring.c b/drivers/net/ethernet/aquantia/atlantic/aq_ring.c
index b261283641a7..d2953a84073e 100644
--- a/drivers/net/ethernet/aquantia/atlantic/aq_ring.c
+++ b/drivers/net/ethernet/aquantia/atlantic/aq_ring.c
@@ -31,6 +31,39 @@ static inline void aq_free_rxpage(struct aq_rxpage *rxpage, struct device *dev)
 	rxpage->page = NULL;
 }
 
+static void aq_unset_rxpage_xdp(struct aq_ring_s *rx_ring,
+				struct aq_ring_buff_s *buff,
+				struct device *dev,
+				struct xdp_buff *xdp)
+{
+	struct aq_ring_buff_s *nbuff = buff;
+	struct skb_shared_info *sinfo;
+	unsigned int next = 0;
+	int i;
+
+	if (xdp_buff_has_frags(xdp)) {
+		sinfo = xdp_get_shared_info_from_buff(xdp);
+
+		for (i = 0; i < sinfo->nr_frags; i++) {
+			skb_frag_t *frag = &sinfo->frags[i];
+			struct page *page;
+
+			page = skb_frag_page(frag);
+
+			dma_unmap_page(dev, page->dma_addr, skb_frag_size(frag),
+				       DMA_FROM_DEVICE);
+		}
+
+		do {
+			next = nbuff->next;
+			nbuff = &rx_ring->buff_ring[next];
+			nbuff->rxdata.page = NULL;
+		} while (!nbuff->is_eop);
+	}
+	dma_unmap_page(dev, buff->rxdata.daddr, PAGE_SIZE, DMA_FROM_DEVICE);
+	buff->rxdata.page = NULL;
+}
+
 static int aq_get_rxpage(struct aq_rxpage *rxpage, struct aq_ring_s *rx_ring)
 {
 	struct device *dev = aq_nic_get_dev(rx_ring->aq_nic);
@@ -316,15 +349,26 @@ bool aq_ring_tx_clean(struct aq_ring_s *self)
 			}
 		}
 
-		if (unlikely(buff->is_eop && buff->skb)) {
+		if (likely(!buff->is_eop))
+			goto out;
+
+		if (buff->skb) {
 			u64_stats_update_begin(&self->stats.tx.syncp);
 			++self->stats.tx.packets;
 			self->stats.tx.bytes += buff->skb->len;
 			u64_stats_update_end(&self->stats.tx.syncp);
-
 			dev_kfree_skb_any(buff->skb);
-			buff->skb = NULL;
+		} else if (buff->xdpf) {
+			u64_stats_update_begin(&self->stats.tx.syncp);
+			++self->stats.tx.packets;
+			self->stats.tx.bytes += xdp_get_frame_len(buff->xdpf);
+			u64_stats_update_end(&self->stats.tx.syncp);
+			xdp_return_frame_rx_napi(buff->xdpf);
 		}
+
+out:
+		buff->skb = NULL;
+		buff->xdpf = NULL;
 		buff->pa = 0U;
 		buff->eop_index = 0xffffU;
 		self->sw_head = aq_ring_next_dx(self, self->sw_head);
@@ -357,11 +401,136 @@ static void aq_rx_checksum(struct aq_ring_s *self,
 		__skb_incr_checksum_unnecessary(skb);
 }
 
-#define AQ_SKB_ALIGN SKB_DATA_ALIGN(sizeof(struct skb_shared_info))
-int aq_ring_rx_clean(struct aq_ring_s *self,
-		     struct napi_struct *napi,
-		     int *work_done,
-		     int budget)
+static struct sk_buff *aq_xdp_run_prog(struct aq_nic_s *aq_nic,
+				       struct xdp_buff *xdp,
+				       struct aq_ring_s *rx_ring,
+				       struct aq_ring_buff_s *buff)
+{
+	int result = NETDEV_TX_BUSY;
+	struct aq_ring_s *tx_ring;
+	struct xdp_frame *xdpf;
+	struct bpf_prog *prog;
+	u32 act = XDP_ABORTED;
+	struct sk_buff *skb;
+
+	u64_stats_update_begin(&rx_ring->stats.rx.syncp);
+	++rx_ring->stats.rx.packets;
+	rx_ring->stats.rx.bytes += xdp_get_buff_len(xdp);
+	u64_stats_update_end(&rx_ring->stats.rx.syncp);
+
+	prog = READ_ONCE(rx_ring->xdp_prog);
+	if (!prog)
+		goto pass;
+
+	prefetchw(xdp->data_hard_start); /* xdp_frame write */
+
+	/* single buffer XDP program, but packet is multi buffer, aborted */
+	if (xdp_buff_has_frags(xdp) && !prog->aux->xdp_has_frags)
+		goto out_aborted;
+
+	act = bpf_prog_run_xdp(prog, xdp);
+	switch (act) {
+	case XDP_PASS:
+pass:
+		xdpf = xdp_convert_buff_to_frame(xdp);
+		if (unlikely(!xdpf))
+			goto out_aborted;
+		skb = xdp_build_skb_from_frame(xdpf, aq_nic->ndev);
+		if (!skb)
+			goto out_aborted;
+		u64_stats_update_begin(&rx_ring->stats.rx.syncp);
+		++rx_ring->stats.rx.xdp_pass;
+		u64_stats_update_end(&rx_ring->stats.rx.syncp);
+		aq_unset_rxpage_xdp(rx_ring, buff, &aq_nic->ndev->dev, xdp);
+		return skb;
+	case XDP_TX:
+		xdpf = xdp_convert_buff_to_frame(xdp);
+		if (unlikely(!xdpf))
+			goto out_aborted;
+		tx_ring = aq_nic->aq_ring_tx[rx_ring->idx];
+		result = aq_nic_xmit_xdpf(aq_nic, tx_ring, xdpf);
+		if (result == NETDEV_TX_BUSY)
+			goto out_aborted;
+		u64_stats_update_begin(&rx_ring->stats.rx.syncp);
+		++rx_ring->stats.rx.xdp_tx;
+		u64_stats_update_end(&rx_ring->stats.rx.syncp);
+		aq_unset_rxpage_xdp(rx_ring, buff, &aq_nic->ndev->dev, xdp);
+		break;
+	case XDP_REDIRECT:
+		if (xdp_do_redirect(aq_nic->ndev, xdp, prog) < 0)
+			goto out_aborted;
+		xdp_do_flush();
+		u64_stats_update_begin(&rx_ring->stats.rx.syncp);
+		++rx_ring->stats.rx.xdp_redirect;
+		u64_stats_update_end(&rx_ring->stats.rx.syncp);
+		aq_unset_rxpage_xdp(rx_ring, buff, &aq_nic->ndev->dev, xdp);
+		break;
+	default:
+		fallthrough;
+	case XDP_ABORTED:
+out_aborted:
+		u64_stats_update_begin(&rx_ring->stats.rx.syncp);
+		++rx_ring->stats.rx.xdp_aborted;
+		u64_stats_update_end(&rx_ring->stats.rx.syncp);
+		trace_xdp_exception(aq_nic->ndev, prog, act);
+		bpf_warn_invalid_xdp_action(aq_nic->ndev, prog, act);
+		break;
+	case XDP_DROP:
+		u64_stats_update_begin(&rx_ring->stats.rx.syncp);
+		++rx_ring->stats.rx.xdp_drop;
+		u64_stats_update_end(&rx_ring->stats.rx.syncp);
+		break;
+	}
+
+	return ERR_PTR(-result);
+}
+
+static bool aq_add_rx_fragment(struct device *dev,
+			       struct aq_ring_s *ring,
+			       struct aq_ring_buff_s *buff,
+			       struct xdp_buff *xdp)
+{
+	struct skb_shared_info *sinfo = xdp_get_shared_info_from_buff(xdp);
+	struct aq_ring_buff_s *buff_ = buff;
+
+	memset(sinfo, 0, sizeof(*sinfo));
+	do {
+		skb_frag_t *frag;
+
+		if (unlikely(sinfo->nr_frags >= MAX_SKB_FRAGS))
+			return true;
+
+		frag = &sinfo->frags[sinfo->nr_frags++];
+		buff_ = &ring->buff_ring[buff_->next];
+		dma_sync_single_range_for_cpu(dev,
+					      buff_->rxdata.daddr,
+					      buff_->rxdata.pg_off,
+					      buff_->len,
+					      DMA_FROM_DEVICE);
+		skb_frag_off_set(frag, buff_->rxdata.pg_off);
+		skb_frag_size_set(frag, buff_->len);
+		sinfo->xdp_frags_size += buff_->len;
+		__skb_frag_set_page(frag, buff_->rxdata.page);
+
+		buff_->is_cleaned = 1;
+
+		buff->is_ip_cso &= buff_->is_ip_cso;
+		buff->is_udp_cso &= buff_->is_udp_cso;
+		buff->is_tcp_cso &= buff_->is_tcp_cso;
+		buff->is_cso_err |= buff_->is_cso_err;
+
+		if (page_is_pfmemalloc(buff_->rxdata.page))
+			xdp_buff_set_frag_pfmemalloc(xdp);
+
+	} while (!buff_->is_eop);
+
+	xdp_buff_set_frags_flag(xdp);
+
+	return false;
+}
+
+static int __aq_ring_rx_clean(struct aq_ring_s *self, struct napi_struct *napi,
+			      int *work_done, int budget)
 {
 	struct net_device *ndev = aq_nic_get_ndev(self->aq_nic);
 	bool is_rsc_completed = true;
@@ -528,6 +697,148 @@ int aq_ring_rx_clean(struct aq_ring_s *self,
 	return err;
 }
 
+static int __aq_ring_xdp_clean(struct aq_ring_s *rx_ring,
+			       struct napi_struct *napi, int *work_done,
+			       int budget)
+{
+	struct aq_nic_s *aq_nic = rx_ring->aq_nic;
+	bool is_rsc_completed = true;
+	struct device *dev;
+	int err = 0;
+
+	dev = aq_nic_get_dev(aq_nic);
+
+	for (; (rx_ring->sw_head != rx_ring->hw_head) && budget;
+		rx_ring->sw_head = aq_ring_next_dx(rx_ring, rx_ring->sw_head),
+		--budget, ++(*work_done)) {
+		struct aq_ring_buff_s *buff = &rx_ring->buff_ring[rx_ring->sw_head];
+		bool is_ptp_ring = aq_ptp_ring(rx_ring->aq_nic, rx_ring);
+		struct aq_ring_buff_s *buff_ = NULL;
+		struct sk_buff *skb = NULL;
+		unsigned int next_ = 0U;
+		struct xdp_buff xdp;
+		void *hard_start;
+
+		if (buff->is_cleaned)
+			continue;
+
+		if (!buff->is_eop) {
+			buff_ = buff;
+			do {
+				if (buff_->next >= rx_ring->size) {
+					err = -EIO;
+					goto err_exit;
+				}
+				next_ = buff_->next;
+				buff_ = &rx_ring->buff_ring[next_];
+				is_rsc_completed =
+					aq_ring_dx_in_range(rx_ring->sw_head,
+							    next_,
+							    rx_ring->hw_head);
+
+				if (unlikely(!is_rsc_completed))
+					break;
+
+				buff->is_error |= buff_->is_error;
+				buff->is_cso_err |= buff_->is_cso_err;
+			} while (!buff_->is_eop);
+
+			if (!is_rsc_completed) {
+				err = 0;
+				goto err_exit;
+			}
+			if (buff->is_error ||
+			    (buff->is_lro && buff->is_cso_err)) {
+				buff_ = buff;
+				do {
+					if (buff_->next >= rx_ring->size) {
+						err = -EIO;
+						goto err_exit;
+					}
+					next_ = buff_->next;
+					buff_ = &rx_ring->buff_ring[next_];
+
+					buff_->is_cleaned = true;
+				} while (!buff_->is_eop);
+
+				u64_stats_update_begin(&rx_ring->stats.rx.syncp);
+				++rx_ring->stats.rx.errors;
+				u64_stats_update_end(&rx_ring->stats.rx.syncp);
+				continue;
+			}
+		}
+
+		if (buff->is_error) {
+			u64_stats_update_begin(&rx_ring->stats.rx.syncp);
+			++rx_ring->stats.rx.errors;
+			u64_stats_update_end(&rx_ring->stats.rx.syncp);
+			continue;
+		}
+
+		dma_sync_single_range_for_cpu(dev,
+					      buff->rxdata.daddr,
+					      buff->rxdata.pg_off,
+					      buff->len, DMA_FROM_DEVICE);
+		hard_start = page_address(buff->rxdata.page);
+
+		if (is_ptp_ring)
+			buff->len -=
+				aq_ptp_extract_ts(rx_ring->aq_nic, skb,
+						  aq_buf_vaddr(&buff->rxdata),
+						  buff->len);
+
+		/* page_order is always 0 if xdp is enabled */
+		xdp_init_buff(&xdp, PAGE_SIZE, &rx_ring->xdp_rxq);
+		xdp_prepare_buff(&xdp, hard_start, rx_ring->page_offset,
+				 buff->len, true);
+		if (!buff->is_eop) {
+			if (aq_add_rx_fragment(dev, rx_ring, buff, &xdp)) {
+				u64_stats_update_begin(&rx_ring->stats.rx.syncp);
+				++rx_ring->stats.rx.packets;
+				rx_ring->stats.rx.bytes += xdp_get_buff_len(&xdp);
+				++rx_ring->stats.rx.xdp_aborted;
+				u64_stats_update_end(&rx_ring->stats.rx.syncp);
+				continue;
+			}
+		}
+
+		skb = aq_xdp_run_prog(aq_nic, &xdp, rx_ring, buff);
+		if (IS_ERR(skb) || !skb)
+			continue;
+
+		if (buff->is_vlan)
+			__vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q),
+					       buff->vlan_rx_tag);
+
+		aq_rx_checksum(rx_ring, buff, skb);
+
+		skb_set_hash(skb, buff->rss_hash,
+			     buff->is_hash_l4 ? PKT_HASH_TYPE_L4 :
+			     PKT_HASH_TYPE_NONE);
+		/* Send all PTP traffic to 0 queue */
+		skb_record_rx_queue(skb,
+				    is_ptp_ring ? 0
+						: AQ_NIC_RING2QMAP(rx_ring->aq_nic,
+								   rx_ring->idx));
+
+		napi_gro_receive(napi, skb);
+	}
+
+err_exit:
+	return err;
+}
+
+int aq_ring_rx_clean(struct aq_ring_s *self,
+		     struct napi_struct *napi,
+		     int *work_done,
+		     int budget)
+{
+	if (static_branch_unlikely(&aq_xdp_locking_key))
+		return __aq_ring_xdp_clean(self, napi, work_done, budget);
+	else
+		return __aq_ring_rx_clean(self, napi, work_done, budget);
+}
+
 void aq_ring_hwts_rx_clean(struct aq_ring_s *self, struct aq_nic_s *aq_nic)
 {
 #if IS_REACHABLE(CONFIG_PTP_1588_CLOCK)
@@ -617,6 +928,14 @@ unsigned int aq_ring_fill_stats_data(struct aq_ring_s *self, u64 *data)
 			data[++count] = self->stats.rx.alloc_fails;
 			data[++count] = self->stats.rx.skb_alloc_fails;
 			data[++count] = self->stats.rx.polls;
+			data[++count] = self->stats.rx.pg_flips;
+			data[++count] = self->stats.rx.pg_reuses;
+			data[++count] = self->stats.rx.xdp_aborted;
+			data[++count] = self->stats.rx.xdp_drop;
+			data[++count] = self->stats.rx.xdp_pass;
+			data[++count] = self->stats.rx.xdp_tx;
+			data[++count] = self->stats.rx.xdp_invalid;
+			data[++count] = self->stats.rx.xdp_redirect;
 		} while (u64_stats_fetch_retry_irq(&self->stats.rx.syncp, start));
 	} else {
 		/* This data should mimic aq_ethtool_queue_tx_stat_names structure */
diff --git a/drivers/net/ethernet/aquantia/atlantic/aq_ring.h b/drivers/net/ethernet/aquantia/atlantic/aq_ring.h
index 168002657629..6a86d9cfac35 100644
--- a/drivers/net/ethernet/aquantia/atlantic/aq_ring.h
+++ b/drivers/net/ethernet/aquantia/atlantic/aq_ring.h
@@ -105,6 +105,12 @@ struct aq_ring_stats_rx_s {
 	u64 pg_losts;
 	u64 pg_flips;
 	u64 pg_reuses;
+	u64 xdp_aborted;
+	u64 xdp_drop;
+	u64 xdp_pass;
+	u64 xdp_tx;
+	u64 xdp_invalid;
+	u64 xdp_redirect;
 };
 
 struct aq_ring_stats_tx_s {
-- 
2.17.1

[PATCH net-next v4 3/3] net: atlantic: Implement .ndo_xdp_xmit handler

[Taehee Yoo]

aq_xdp_xmit() is the callback function of .ndo_xdp_xmit.
It internally calls aq_nic_xmit_xdpf() to send packet.

Signed-off-by: Taehee Yoo <ap420073@gmail.com>
---

v4:
 - No changed

v3:
 - No changed

v2:
 - No changed

 .../net/ethernet/aquantia/atlantic/aq_main.c  |  1 +
 .../net/ethernet/aquantia/atlantic/aq_ring.c  | 23 +++++++++++++++++++
 .../net/ethernet/aquantia/atlantic/aq_ring.h  |  2 ++
 3 files changed, 26 insertions(+)

diff --git a/drivers/net/ethernet/aquantia/atlantic/aq_main.c b/drivers/net/ethernet/aquantia/atlantic/aq_main.c
index 43012648a351..a0c428db886f 100644
--- a/drivers/net/ethernet/aquantia/atlantic/aq_main.c
+++ b/drivers/net/ethernet/aquantia/atlantic/aq_main.c
@@ -508,6 +508,7 @@ static const struct net_device_ops aq_ndev_ops = {
 	.ndo_vlan_rx_kill_vid = aq_ndo_vlan_rx_kill_vid,
 	.ndo_setup_tc = aq_ndo_setup_tc,
 	.ndo_bpf = aq_xdp,
+	.ndo_xdp_xmit = aq_xdp_xmit,
 };
 
 static int __init aq_ndev_init_module(void)
diff --git a/drivers/net/ethernet/aquantia/atlantic/aq_ring.c b/drivers/net/ethernet/aquantia/atlantic/aq_ring.c
index d2953a84073e..e788f9095a96 100644
--- a/drivers/net/ethernet/aquantia/atlantic/aq_ring.c
+++ b/drivers/net/ethernet/aquantia/atlantic/aq_ring.c
@@ -401,6 +401,29 @@ static void aq_rx_checksum(struct aq_ring_s *self,
 		__skb_incr_checksum_unnecessary(skb);
 }
 
+int aq_xdp_xmit(struct net_device *dev, int num_frames,
+		struct xdp_frame **frames, u32 flags)
+{
+	struct aq_nic_s *aq_nic = netdev_priv(dev);
+	unsigned int vec, i, drop = 0;
+	int cpu = smp_processor_id();
+	struct aq_nic_cfg_s *aq_cfg;
+	struct aq_ring_s *ring;
+
+	aq_cfg = aq_nic_get_cfg(aq_nic);
+	vec = cpu % aq_cfg->vecs;
+	ring = aq_nic->aq_ring_tx[AQ_NIC_CFG_TCVEC2RING(aq_cfg, 0, vec)];
+
+	for (i = 0; i < num_frames; i++) {
+		struct xdp_frame *xdpf = frames[i];
+
+		if (aq_nic_xmit_xdpf(aq_nic, ring, xdpf) == NETDEV_TX_BUSY)
+			drop++;
+	}
+
+	return num_frames - drop;
+}
+
 static struct sk_buff *aq_xdp_run_prog(struct aq_nic_s *aq_nic,
 				       struct xdp_buff *xdp,
 				       struct aq_ring_s *rx_ring,
diff --git a/drivers/net/ethernet/aquantia/atlantic/aq_ring.h b/drivers/net/ethernet/aquantia/atlantic/aq_ring.h
index 6a86d9cfac35..31e19dff6c1e 100644
--- a/drivers/net/ethernet/aquantia/atlantic/aq_ring.h
+++ b/drivers/net/ethernet/aquantia/atlantic/aq_ring.h
@@ -197,6 +197,8 @@ void aq_ring_update_queue_state(struct aq_ring_s *ring);
 void aq_ring_queue_wake(struct aq_ring_s *ring);
 void aq_ring_queue_stop(struct aq_ring_s *ring);
 bool aq_ring_tx_clean(struct aq_ring_s *self);
+int aq_xdp_xmit(struct net_device *dev, int num_frames,
+		struct xdp_frame **frames, u32 flags);
 int aq_ring_rx_clean(struct aq_ring_s *self,
 		     struct napi_struct *napi,
 		     int *work_done,
-- 
2.17.1

Re: [PATCH net-next v4 0/3] net: atlantic: Add XDP support

[Paolo Abeni]

On Fri, 2022-04-08 at 18:17 +0000, Taehee Yoo wrote:
> This patchset is to make atlantic to support multi-buffer XDP.
> 
> The first patch implement control plane of xdp.
> The aq_xdp(), callback of .xdp_bpf is added.
> 
> The second patch implements data plane of xdp.
> XDP_TX, XDP_DROP, and XDP_PASS is supported.
> __aq_ring_xdp_clean() is added to receive and execute xdp program.
> aq_nic_xmit_xdpf() is added to send packet by XDP.
> 
> The third patch implements callback of .ndo_xdp_xmit.
> aq_xdp_xmit() is added to send redirected packets and it internally
> calls aq_nic_xmit_xdpf().
> 
> Memory model is MEM_TYPE_PAGE_ORDER0 so it doesn't reuse rx page when
> XDP_TX, XDP_PASS, XDP_REDIRECT.
> 
> Default the maximum rx frame size is 2K.
> If xdp is attached, size is changed to about 3K.
> It can be reused when XDP_DROP, and XDP_ABORTED.
> 
> Atlantic driver has AQ_CFG_RX_PAGEORDER option and it will be always 0
> if xdp is attached.
> 
> LRO will be disabled if XDP program supports only single buffer.
> 
> AQC chip supports 32 multi-queues and 8 vectors(irq).
> There are two options.
> 1. under 8 cores and maximum 4 tx queues per core.
> 2. under 4 cores and maximum 8 tx queues per core.
> 
> Like other drivers, these tx queues can be used only for XDP_TX,
> XDP_REDIRECT queue. If so, no tx_lock is needed.
> But this patchset doesn't use this strategy because getting hardware tx
> queue index cost is too high.
> So, tx_lock is used in the aq_nic_xmit_xdpf().
> 
> single-core, single queue, 80% cpu utilization.
> 
>   30.75%  bpf_prog_xxx_xdp_prog_tx  [k] bpf_prog_xxx_xdp_prog_tx
>   10.35%  [kernel]                  [k] aq_hw_read_reg <---------- here
>    4.38%  [kernel]                  [k] get_page_from_freelist
> 
> single-core, 8 queues, 100% cpu utilization, half PPS.
> 
>   45.56%  [kernel]                  [k] aq_hw_read_reg <---------- here
>   17.58%  bpf_prog_xxx_xdp_prog_tx  [k] bpf_prog_xxx_xdp_prog_tx
>    4.72%  [kernel]                  [k] hw_atl_b0_hw_ring_rx_receive
> 
> Performance result(64 Byte)
> 1. XDP_TX
>   a. xdp_geieric, single core
>     - 2.5Mpps, 100% cpu
>   b. xdp_driver, single core
>     - 4.5Mpps, 80% cpu
>   c. xdp_generic, 8 core(hyper thread)
>     - 6.3Mpps, 5~10% cpu
>   d. xdp_driver, 8 core(hyper thread)
>     - 6.3Mpps, 5% cpu
> 
> 2. XDP_REDIRECT
>   a. xdp_generic, single core
>     - 2.3Mpps
>   b. xdp_driver, single core
>     - 4.5Mpps
> 
> v4:
>  - Fix compile warning
> 
> v3:
>  - Change wrong PPS performance result 40% -> 80% in single
>    core(Intel i3-12100)
>  - Separate aq_nic_map_xdp() from aq_nic_map_skb()
>  - Drop multi buffer packets if single buffer XDP is attached
>  - Disable LRO when single buffer XDP is attached
>  - Use xdp_get_{frame/buff}_len()
> 
> v2:
>  - Do not use inline in C file
> 
> Taehee Yoo (3):
>   net: atlantic: Implement xdp control plane
>   net: atlantic: Implement xdp data plane
>   net: atlantic: Implement .ndo_xdp_xmit handler
> 
>  .../net/ethernet/aquantia/atlantic/aq_cfg.h   |   1 +
>  .../ethernet/aquantia/atlantic/aq_ethtool.c   |   8 +
>  .../net/ethernet/aquantia/atlantic/aq_main.c  |  87 ++++
>  .../net/ethernet/aquantia/atlantic/aq_main.h  |   2 +
>  .../net/ethernet/aquantia/atlantic/aq_nic.c   | 137 ++++++
>  .../net/ethernet/aquantia/atlantic/aq_nic.h   |   5 +
>  .../net/ethernet/aquantia/atlantic/aq_ring.c  | 415 ++++++++++++++++--
>  .../net/ethernet/aquantia/atlantic/aq_ring.h  |  17 +
>  .../net/ethernet/aquantia/atlantic/aq_vec.c   |  23 +-
>  .../net/ethernet/aquantia/atlantic/aq_vec.h   |   6 +
>  .../aquantia/atlantic/hw_atl/hw_atl_a0.c      |   6 +-
>  .../aquantia/atlantic/hw_atl/hw_atl_b0.c      |  10 +-
>  12 files changed, 675 insertions(+), 42 deletions(-)
> 
@Igor: this should address you concerns on v2, could you please have a
look?

Thanks!

Paolo

Re: [EXT] [PATCH net-next v4 0/3] net: atlantic: Add XDP support

[Igor Russkikh]

> v4:
>  - Fix compile warning
> 
> v3:
>  - Change wrong PPS performance result 40% -> 80% in single
>    core(Intel i3-12100)
>  - Separate aq_nic_map_xdp() from aq_nic_map_skb()
>  - Drop multi buffer packets if single buffer XDP is attached
>  - Disable LRO when single buffer XDP is attached
>  - Use xdp_get_{frame/buff}_len()

Hi Taehee, thanks for taking care of that!

Reviewed-by: Igor Russkikh <irusskikh@marvell.com>

A small notice about the selection of 3K packet size for XDP.
Its a kind of compromise I think, because with common 1.4K MTU we'll get wasted
2K bytes minimum per packet.

I was thinking it would be possible to reuse the existing page flipping technique
together with higher page_order, to keep default 2K fragment size.
E.g.
( 256(xdp_head)+2K(pkt frag) ) x 3 (flips) = ~7K

Meaning we can allocate 8K (page_order=1) pages, and fit three xdp packets into each, wasting only 1K per three packets.

But its just kind of an idea for future optimization.

Regards,
  Igor

Re: [EXT] [PATCH net-next v4 0/3] net: atlantic: Add XDP support

[Taehee Yoo]

2022. 4. 13. 오후 4:52에 Igor Russkikh 이(가) 쓴 글:

Hi Igor,

Thank you so much for your review!

 >
 >
 >> v4:
 >>   - Fix compile warning
 >>
 >> v3:
 >>   - Change wrong PPS performance result 40% -> 80% in single
 >>     core(Intel i3-12100)
 >>   - Separate aq_nic_map_xdp() from aq_nic_map_skb()
 >>   - Drop multi buffer packets if single buffer XDP is attached
 >>   - Disable LRO when single buffer XDP is attached
 >>   - Use xdp_get_{frame/buff}_len()
 >
 > Hi Taehee, thanks for taking care of that!
 >
 > Reviewed-by: Igor Russkikh <irusskikh@marvell.com>
 >
 > A small notice about the selection of 3K packet size for XDP.
 > Its a kind of compromise I think, because with common 1.4K MTU we'll 
get wasted
 > 2K bytes minimum per packet.
 >
 > I was thinking it would be possible to reuse the existing page 
flipping technique
 > together with higher page_order, to keep default 2K fragment size.
 > E.g.
 > ( 256(xdp_head)+2K(pkt frag) ) x 3 (flips) = ~7K
 >
 > Meaning we can allocate 8K (page_order=1) pages, and fit three xdp 
packets into each, wasting only 1K per three packets.
 >
 > But its just kind of an idea for future optimization.
 >

Yes, I fully agree with your idea.
When I developed an initial version of this patchset, I simply tried 
that idea.
I expected to reduce CPU utilization(not for memory optimization), but 
there is no difference because page_ref_{inc/dec}() cost is too high.
So, if we tried to switch from MEM_TYPE_PAGE_ORDER0 to 
MEM_TYPE_PAGE_SHARED, I think we should use a littie bit different 
flipping strategy like ixgbe.
If so, we would achieve memory optimization and CPU optimization.

Thanks a lot,
Taehee Yoo

 > Regards,
 >    Igor