[PATCH net-next 0/9] nfp: LSO, checksum and XDP datapath updates

[PATCH net-next 0/9] nfp: LSO, checksum and XDP datapath updates

[Jakub Kicinski]

Hi!

This series introduces a number of refinements to standard features
like LSO and checksum offload.  Three major features are support for
CHECKSUM_COMPLETE, refinement of TSO handling and another small speed
up for XDP TX.  This series also switches from depending on some 
app FW<>driver ABI versions to heavier use of capabilities.


Edwin Peer (3):
  nfp: rename l4_offset in struct nfp_net_tx_desc to lso_hdrlen
  nfp: support LSO2 capability
  nfp: version independent support for chained RSS metadata

Jakub Kicinski (6):
  nfp: don't enable TSO on the device when disabled
  nfp: don't assume RSS and IRQ moderation are always enabled
  nfp: add CHECKSUM_COMPLETE support
  nfp: complete the XDP TX ring only when it's full
  nfp: add a helper for wrapping descriptor index
  nfp: eliminate an if statement in calculation of completed frames

 drivers/net/ethernet/netronome/nfp/nfp_net.h       |  19 ++-
 .../net/ethernet/netronome/nfp/nfp_net_common.c    | 179 +++++++++++++--------
 drivers/net/ethernet/netronome/nfp/nfp_net_ctrl.h  |  18 ++-
 .../net/ethernet/netronome/nfp/nfp_net_ethtool.c   |  12 +-
 4 files changed, 149 insertions(+), 79 deletions(-)

-- 
2.11.0

[PATCH net-next 1/9] nfp: don't enable TSO on the device when disabled

[Jakub Kicinski]

We advertise TSO to the stack but leave it disabled by default.
Make sure it's not only disabled in the netdev features but
also on the device itself.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Simon Horman <simon.horman@netronome.com>
---
 drivers/net/ethernet/netronome/nfp/nfp_net_common.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
index 82bd6b0935f1..76251a09a1f3 100644
--- a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
+++ b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
@@ -3286,6 +3286,7 @@ int nfp_net_netdev_init(struct net_device *netdev)
 
 	/* Advertise but disable TSO by default. */
 	netdev->features &= ~(NETIF_F_TSO | NETIF_F_TSO6);
+	nn->dp.ctrl &= ~NFP_NET_CFG_CTRL_LSO;
 
 	/* Allow L2 Broadcast and Multicast through by default, if supported */
 	if (nn->cap & NFP_NET_CFG_CTRL_L2BC)
-- 
2.11.0

[PATCH net-next 2/9] nfp: rename l4_offset in struct nfp_net_tx_desc to lso_hdrlen

[Jakub Kicinski]

From: Edwin Peer <edwin.peer@netronome.com>

The l4_offset field referred to by NFD is confusingly named. It is not the
offset of the L4 transport header, but rather the L4 payload.

The LSO2 capability supported by alternative device firmware requires
the actual L4 offset, thus the rename seems prudent.

Signed-off-by: Edwin Peer <edwin.peer@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Simon Horman <simon.horman@netronome.com>
---
 drivers/net/ethernet/netronome/nfp/nfp_net.h        | 2 +-
 drivers/net/ethernet/netronome/nfp/nfp_net_common.c | 6 +++---
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/netronome/nfp/nfp_net.h b/drivers/net/ethernet/netronome/nfp/nfp_net.h
index fcf81b3be830..6bad11e5b845 100644
--- a/drivers/net/ethernet/netronome/nfp/nfp_net.h
+++ b/drivers/net/ethernet/netronome/nfp/nfp_net.h
@@ -153,7 +153,7 @@ struct nfp_net_tx_desc {
 			__le32 dma_addr_lo; /* Low 32bit of host buf addr */
 
 			__le16 mss;	/* MSS to be used for LSO */
-			u8 l4_offset;	/* LSO, where the L4 data starts */
+			u8 lso_hdrlen;	/* LSO, TCP payload offset */
 			u8 flags;	/* TX Flags, see @PCIE_DESC_TX_* */
 
 			__le16 vlan;	/* VLAN tag to add if indicated */
diff --git a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
index 76251a09a1f3..0cebe9098451 100644
--- a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
+++ b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
@@ -677,7 +677,7 @@ static void nfp_net_tx_tso(struct nfp_net_r_vector *r_vec,
 	txbuf->real_len += hdrlen * (txbuf->pkt_cnt - 1);
 
 	mss = skb_shinfo(skb)->gso_size & PCIE_DESC_TX_MSS_MASK;
-	txd->l4_offset = hdrlen;
+	txd->lso_hdrlen = hdrlen;
 	txd->mss = cpu_to_le16(mss);
 	txd->flags |= PCIE_DESC_TX_LSO;
 
@@ -823,7 +823,7 @@ static int nfp_net_tx(struct sk_buff *skb, struct net_device *netdev)
 
 	txd->flags = 0;
 	txd->mss = 0;
-	txd->l4_offset = 0;
+	txd->lso_hdrlen = 0;
 
 	nfp_net_tx_tso(r_vec, txbuf, txd, skb);
 
@@ -1515,7 +1515,7 @@ nfp_net_tx_xdp_buf(struct nfp_net_dp *dp, struct nfp_net_rx_ring *rx_ring,
 
 	txd->flags = 0;
 	txd->mss = 0;
-	txd->l4_offset = 0;
+	txd->lso_hdrlen = 0;
 
 	tx_ring->wr_p++;
 	tx_ring->wr_ptr_add++;
-- 
2.11.0

[PATCH net-next 3/9] nfp: support LSO2 capability

[Jakub Kicinski]

From: Edwin Peer <edwin.peer@netronome.com>

Firmware advertising the LSO2 capability exploits driver provided L3 and L4
offsets in order to avoid parsing packet headers in the TX path. The vlan
field in struct nfp_net_tx_desc is repurposed, making TXVLAN a mutually
exclusive configuration to LSO2.

Signed-off-by: Edwin Peer <edwin.peer@netronome.com>
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
---
 drivers/net/ethernet/netronome/nfp/nfp_net.h       |  9 +++--
 .../net/ethernet/netronome/nfp/nfp_net_common.c    | 38 ++++++++++++++--------
 drivers/net/ethernet/netronome/nfp/nfp_net_ctrl.h  |  7 +++-
 3 files changed, 38 insertions(+), 16 deletions(-)

diff --git a/drivers/net/ethernet/netronome/nfp/nfp_net.h b/drivers/net/ethernet/netronome/nfp/nfp_net.h
index 6bad11e5b845..c6b7141dc50d 100644
--- a/drivers/net/ethernet/netronome/nfp/nfp_net.h
+++ b/drivers/net/ethernet/netronome/nfp/nfp_net.h
@@ -155,8 +155,13 @@ struct nfp_net_tx_desc {
 			__le16 mss;	/* MSS to be used for LSO */
 			u8 lso_hdrlen;	/* LSO, TCP payload offset */
 			u8 flags;	/* TX Flags, see @PCIE_DESC_TX_* */
-
-			__le16 vlan;	/* VLAN tag to add if indicated */
+			union {
+				struct {
+					u8 l3_offset; /* L3 header offset */
+					u8 l4_offset; /* L4 header offset */
+				};
+				__le16 vlan; /* VLAN tag to add if indicated */
+			};
 			__le16 data_len; /* Length of frame + meta data */
 		} __packed;
 		__le32 vals[4];
diff --git a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
index 0cebe9098451..5e8049a84d16 100644
--- a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
+++ b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
@@ -667,11 +667,16 @@ static void nfp_net_tx_tso(struct nfp_net_r_vector *r_vec,
 	if (!skb_is_gso(skb))
 		return;
 
-	if (!skb->encapsulation)
+	if (!skb->encapsulation) {
+		txd->l3_offset = skb_network_offset(skb);
+		txd->l4_offset = skb_transport_offset(skb);
 		hdrlen = skb_transport_offset(skb) + tcp_hdrlen(skb);
-	else
+	} else {
+		txd->l3_offset = skb_inner_network_offset(skb);
+		txd->l4_offset = skb_inner_transport_offset(skb);
 		hdrlen = skb_inner_transport_header(skb) - skb->data +
 			inner_tcp_hdrlen(skb);
+	}
 
 	txbuf->pkt_cnt = skb_shinfo(skb)->gso_segs;
 	txbuf->real_len += hdrlen * (txbuf->pkt_cnt - 1);
@@ -825,10 +830,9 @@ static int nfp_net_tx(struct sk_buff *skb, struct net_device *netdev)
 	txd->mss = 0;
 	txd->lso_hdrlen = 0;
 
+	/* Do not reorder - tso may adjust pkt cnt, vlan may override fields */
 	nfp_net_tx_tso(r_vec, txbuf, txd, skb);
-
 	nfp_net_tx_csum(dp, r_vec, txbuf, txd, skb);
-
 	if (skb_vlan_tag_present(skb) && dp->ctrl & NFP_NET_CFG_CTRL_TXVLAN) {
 		txd->flags |= PCIE_DESC_TX_VLAN;
 		txd->vlan = cpu_to_le16(skb_vlan_tag_get(skb));
@@ -2724,9 +2728,10 @@ static int nfp_net_set_features(struct net_device *netdev,
 
 	if (changed & (NETIF_F_TSO | NETIF_F_TSO6)) {
 		if (features & (NETIF_F_TSO | NETIF_F_TSO6))
-			new_ctrl |= NFP_NET_CFG_CTRL_LSO;
+			new_ctrl |= nn->cap & NFP_NET_CFG_CTRL_LSO2 ?:
+					      NFP_NET_CFG_CTRL_LSO;
 		else
-			new_ctrl &= ~NFP_NET_CFG_CTRL_LSO;
+			new_ctrl &= ~NFP_NET_CFG_CTRL_LSO_ANY;
 	}
 
 	if (changed & NETIF_F_HW_VLAN_CTAG_RX) {
@@ -3032,7 +3037,7 @@ void nfp_net_info(struct nfp_net *nn)
 		nn->fw_ver.resv, nn->fw_ver.class,
 		nn->fw_ver.major, nn->fw_ver.minor,
 		nn->max_mtu);
-	nn_info(nn, "CAP: %#x %s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s\n",
+	nn_info(nn, "CAP: %#x %s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s\n",
 		nn->cap,
 		nn->cap & NFP_NET_CFG_CTRL_PROMISC  ? "PROMISC "  : "",
 		nn->cap & NFP_NET_CFG_CTRL_L2BC     ? "L2BCFILT " : "",
@@ -3043,7 +3048,8 @@ void nfp_net_info(struct nfp_net *nn)
 		nn->cap & NFP_NET_CFG_CTRL_TXVLAN   ? "TXVLAN "   : "",
 		nn->cap & NFP_NET_CFG_CTRL_SCATTER  ? "SCATTER "  : "",
 		nn->cap & NFP_NET_CFG_CTRL_GATHER   ? "GATHER "   : "",
-		nn->cap & NFP_NET_CFG_CTRL_LSO      ? "TSO "      : "",
+		nn->cap & NFP_NET_CFG_CTRL_LSO      ? "TSO1 "     : "",
+		nn->cap & NFP_NET_CFG_CTRL_LSO2     ? "TSO2 "     : "",
 		nn->cap & NFP_NET_CFG_CTRL_RSS      ? "RSS "      : "",
 		nn->cap & NFP_NET_CFG_CTRL_L2SWITCH ? "L2SWITCH " : "",
 		nn->cap & NFP_NET_CFG_CTRL_MSIXAUTO ? "AUTOMASK " : "",
@@ -3249,9 +3255,11 @@ int nfp_net_netdev_init(struct net_device *netdev)
 		netdev->hw_features |= NETIF_F_SG;
 		nn->dp.ctrl |= NFP_NET_CFG_CTRL_GATHER;
 	}
-	if ((nn->cap & NFP_NET_CFG_CTRL_LSO) && nn->fw_ver.major > 2) {
+	if ((nn->cap & NFP_NET_CFG_CTRL_LSO && nn->fw_ver.major > 2) ||
+	    nn->cap & NFP_NET_CFG_CTRL_LSO2) {
 		netdev->hw_features |= NETIF_F_TSO | NETIF_F_TSO6;
-		nn->dp.ctrl |= NFP_NET_CFG_CTRL_LSO;
+		nn->dp.ctrl |= nn->cap & NFP_NET_CFG_CTRL_LSO2 ?:
+					 NFP_NET_CFG_CTRL_LSO;
 	}
 	if (nn->cap & NFP_NET_CFG_CTRL_RSS) {
 		netdev->hw_features |= NETIF_F_RXHASH;
@@ -3275,8 +3283,12 @@ int nfp_net_netdev_init(struct net_device *netdev)
 		nn->dp.ctrl |= NFP_NET_CFG_CTRL_RXVLAN;
 	}
 	if (nn->cap & NFP_NET_CFG_CTRL_TXVLAN) {
-		netdev->hw_features |= NETIF_F_HW_VLAN_CTAG_TX;
-		nn->dp.ctrl |= NFP_NET_CFG_CTRL_TXVLAN;
+		if (nn->cap & NFP_NET_CFG_CTRL_LSO2) {
+			nn_warn(nn, "Device advertises both TSO2 and TXVLAN. Refusing to enable TXVLAN.\n");
+		} else {
+			netdev->hw_features |= NETIF_F_HW_VLAN_CTAG_TX;
+			nn->dp.ctrl |= NFP_NET_CFG_CTRL_TXVLAN;
+		}
 	}
 
 	netdev->features = netdev->hw_features;
@@ -3286,7 +3298,7 @@ int nfp_net_netdev_init(struct net_device *netdev)
 
 	/* Advertise but disable TSO by default. */
 	netdev->features &= ~(NETIF_F_TSO | NETIF_F_TSO6);
-	nn->dp.ctrl &= ~NFP_NET_CFG_CTRL_LSO;
+	nn->dp.ctrl &= ~NFP_NET_CFG_CTRL_LSO_ANY;
 
 	/* Allow L2 Broadcast and Multicast through by default, if supported */
 	if (nn->cap & NFP_NET_CFG_CTRL_L2BC)
diff --git a/drivers/net/ethernet/netronome/nfp/nfp_net_ctrl.h b/drivers/net/ethernet/netronome/nfp/nfp_net_ctrl.h
index d04ccc9f6116..1575e8fdb541 100644
--- a/drivers/net/ethernet/netronome/nfp/nfp_net_ctrl.h
+++ b/drivers/net/ethernet/netronome/nfp/nfp_net_ctrl.h
@@ -119,7 +119,7 @@
 #define   NFP_NET_CFG_CTRL_TXVLAN         (0x1 <<  7) /* Enable VLAN insert */
 #define   NFP_NET_CFG_CTRL_SCATTER        (0x1 <<  8) /* Scatter DMA */
 #define   NFP_NET_CFG_CTRL_GATHER         (0x1 <<  9) /* Gather DMA */
-#define   NFP_NET_CFG_CTRL_LSO            (0x1 << 10) /* LSO/TSO */
+#define   NFP_NET_CFG_CTRL_LSO            (0x1 << 10) /* LSO/TSO (version 1) */
 #define   NFP_NET_CFG_CTRL_RINGCFG        (0x1 << 16) /* Ring runtime changes */
 #define   NFP_NET_CFG_CTRL_RSS            (0x1 << 17) /* RSS */
 #define   NFP_NET_CFG_CTRL_IRQMOD         (0x1 << 18) /* Interrupt moderation */
@@ -131,6 +131,11 @@
 #define   NFP_NET_CFG_CTRL_VXLAN	  (0x1 << 24) /* VXLAN tunnel support */
 #define   NFP_NET_CFG_CTRL_NVGRE	  (0x1 << 25) /* NVGRE tunnel support */
 #define   NFP_NET_CFG_CTRL_BPF		  (0x1 << 27) /* BPF offload capable */
+#define   NFP_NET_CFG_CTRL_LSO2		  (0x1 << 28) /* LSO/TSO (version 2) */
+
+#define NFP_NET_CFG_CTRL_LSO_ANY	(NFP_NET_CFG_CTRL_LSO | \
+					 NFP_NET_CFG_CTRL_LSO2)
+
 #define NFP_NET_CFG_UPDATE              0x0004
 #define   NFP_NET_CFG_UPDATE_GEN          (0x1 <<  0) /* General update */
 #define   NFP_NET_CFG_UPDATE_RING         (0x1 <<  1) /* Ring config change */
-- 
2.11.0

[PATCH net-next 4/9] nfp: don't assume RSS and IRQ moderation are always enabled

[Jakub Kicinski]

Even if capability for RSS and IRQ moderation are present we may
have not initialized them for control vNIC.  Depend on selected
features mask (ctrl) rather than capabilities (cap) to determine
which features should be enabled.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Simon Horman <simon.horman@netronome.com>
---
 drivers/net/ethernet/netronome/nfp/nfp_net_common.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
index 5e8049a84d16..ae32c0e8d6e6 100644
--- a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
+++ b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
@@ -2201,17 +2201,15 @@ static int nfp_net_set_config_and_enable(struct nfp_net *nn)
 
 	new_ctrl = nn->dp.ctrl;
 
-	if (nn->cap & NFP_NET_CFG_CTRL_RSS) {
+	if (nn->dp.ctrl & NFP_NET_CFG_CTRL_RSS) {
 		nfp_net_rss_write_key(nn);
 		nfp_net_rss_write_itbl(nn);
 		nn_writel(nn, NFP_NET_CFG_RSS_CTRL, nn->rss_cfg);
 		update |= NFP_NET_CFG_UPDATE_RSS;
 	}
 
-	if (nn->cap & NFP_NET_CFG_CTRL_IRQMOD) {
+	if (nn->dp.ctrl & NFP_NET_CFG_CTRL_IRQMOD) {
 		nfp_net_coalesce_write_cfg(nn);
-
-		new_ctrl |= NFP_NET_CFG_CTRL_IRQMOD;
 		update |= NFP_NET_CFG_UPDATE_IRQMOD;
 	}
 
-- 
2.11.0

[PATCH net-next 5/9] nfp: version independent support for chained RSS metadata

[Jakub Kicinski]

From: Edwin Peer <edwin.peer@netronome.com>

ABI version 4 introduced metadata chaining. Using the ABI version to signal
metadata chaining precludes firmware that advertises new capabilities which
rely on prepended metadata from working on older kernels.

Capability bits are thus better suited to signalling the chained metadata
format. A new version of the RSS capability is introduced to distinguish
between the differing metadata formats for ABI versions other than 4.

Signed-off-by: Edwin Peer <edwin.peer@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Simon Horman <simon.horman@netronome.com>
---
 drivers/net/ethernet/netronome/nfp/nfp_net_common.c  | 20 +++++++++++++-------
 drivers/net/ethernet/netronome/nfp/nfp_net_ctrl.h    |  6 +++++-
 drivers/net/ethernet/netronome/nfp/nfp_net_ethtool.c | 12 ++++++------
 3 files changed, 24 insertions(+), 14 deletions(-)

diff --git a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
index ae32c0e8d6e6..cc5a2eaef156 100644
--- a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
+++ b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
@@ -2201,7 +2201,7 @@ static int nfp_net_set_config_and_enable(struct nfp_net *nn)
 
 	new_ctrl = nn->dp.ctrl;
 
-	if (nn->dp.ctrl & NFP_NET_CFG_CTRL_RSS) {
+	if (nn->dp.ctrl & NFP_NET_CFG_CTRL_RSS_ANY) {
 		nfp_net_rss_write_key(nn);
 		nfp_net_rss_write_itbl(nn);
 		nn_writel(nn, NFP_NET_CFG_RSS_CTRL, nn->rss_cfg);
@@ -3035,7 +3035,7 @@ void nfp_net_info(struct nfp_net *nn)
 		nn->fw_ver.resv, nn->fw_ver.class,
 		nn->fw_ver.major, nn->fw_ver.minor,
 		nn->max_mtu);
-	nn_info(nn, "CAP: %#x %s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s\n",
+	nn_info(nn, "CAP: %#x %s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s\n",
 		nn->cap,
 		nn->cap & NFP_NET_CFG_CTRL_PROMISC  ? "PROMISC "  : "",
 		nn->cap & NFP_NET_CFG_CTRL_L2BC     ? "L2BCFILT " : "",
@@ -3048,7 +3048,8 @@ void nfp_net_info(struct nfp_net *nn)
 		nn->cap & NFP_NET_CFG_CTRL_GATHER   ? "GATHER "   : "",
 		nn->cap & NFP_NET_CFG_CTRL_LSO      ? "TSO1 "     : "",
 		nn->cap & NFP_NET_CFG_CTRL_LSO2     ? "TSO2 "     : "",
-		nn->cap & NFP_NET_CFG_CTRL_RSS      ? "RSS "      : "",
+		nn->cap & NFP_NET_CFG_CTRL_RSS      ? "RSS1 "     : "",
+		nn->cap & NFP_NET_CFG_CTRL_RSS2     ? "RSS2 "     : "",
 		nn->cap & NFP_NET_CFG_CTRL_L2SWITCH ? "L2SWITCH " : "",
 		nn->cap & NFP_NET_CFG_CTRL_MSIXAUTO ? "AUTOMASK " : "",
 		nn->cap & NFP_NET_CFG_CTRL_IRQMOD   ? "IRQMOD "   : "",
@@ -3202,14 +3203,18 @@ int nfp_net_netdev_init(struct net_device *netdev)
 	struct nfp_net *nn = netdev_priv(netdev);
 	int err;
 
-	nn->dp.chained_metadata_format = nn->fw_ver.major > 3;
-
 	nn->dp.rx_dma_dir = DMA_FROM_DEVICE;
 
 	/* Get some of the read-only fields from the BAR */
 	nn->cap = nn_readl(nn, NFP_NET_CFG_CAP);
 	nn->max_mtu = nn_readl(nn, NFP_NET_CFG_MAX_MTU);
 
+	/* Chained metadata is signalled by capabilities except in version 4 */
+	nn->dp.chained_metadata_format = nn->fw_ver.major == 4 ||
+					 nn->cap & NFP_NET_CFG_CTRL_CHAIN_META;
+	if (nn->dp.chained_metadata_format && nn->fw_ver.major != 4)
+		nn->cap &= ~NFP_NET_CFG_CTRL_RSS;
+
 	nfp_net_write_mac_addr(nn);
 
 	/* Determine RX packet/metadata boundary offset */
@@ -3259,10 +3264,11 @@ int nfp_net_netdev_init(struct net_device *netdev)
 		nn->dp.ctrl |= nn->cap & NFP_NET_CFG_CTRL_LSO2 ?:
 					 NFP_NET_CFG_CTRL_LSO;
 	}
-	if (nn->cap & NFP_NET_CFG_CTRL_RSS) {
+	if (nn->cap & NFP_NET_CFG_CTRL_RSS_ANY) {
 		netdev->hw_features |= NETIF_F_RXHASH;
 		nfp_net_rss_init(nn);
-		nn->dp.ctrl |= NFP_NET_CFG_CTRL_RSS;
+		nn->dp.ctrl |= nn->cap & NFP_NET_CFG_CTRL_RSS2 ?:
+					 NFP_NET_CFG_CTRL_RSS;
 	}
 	if (nn->cap & NFP_NET_CFG_CTRL_VXLAN &&
 	    nn->cap & NFP_NET_CFG_CTRL_NVGRE) {
diff --git a/drivers/net/ethernet/netronome/nfp/nfp_net_ctrl.h b/drivers/net/ethernet/netronome/nfp/nfp_net_ctrl.h
index 1575e8fdb541..a049c5d6839d 100644
--- a/drivers/net/ethernet/netronome/nfp/nfp_net_ctrl.h
+++ b/drivers/net/ethernet/netronome/nfp/nfp_net_ctrl.h
@@ -121,7 +121,7 @@
 #define   NFP_NET_CFG_CTRL_GATHER         (0x1 <<  9) /* Gather DMA */
 #define   NFP_NET_CFG_CTRL_LSO            (0x1 << 10) /* LSO/TSO (version 1) */
 #define   NFP_NET_CFG_CTRL_RINGCFG        (0x1 << 16) /* Ring runtime changes */
-#define   NFP_NET_CFG_CTRL_RSS            (0x1 << 17) /* RSS */
+#define   NFP_NET_CFG_CTRL_RSS		  (0x1 << 17) /* RSS (version 1) */
 #define   NFP_NET_CFG_CTRL_IRQMOD         (0x1 << 18) /* Interrupt moderation */
 #define   NFP_NET_CFG_CTRL_RINGPRIO       (0x1 << 19) /* Ring priorities */
 #define   NFP_NET_CFG_CTRL_MSIXAUTO       (0x1 << 20) /* MSI-X auto-masking */
@@ -132,9 +132,13 @@
 #define   NFP_NET_CFG_CTRL_NVGRE	  (0x1 << 25) /* NVGRE tunnel support */
 #define   NFP_NET_CFG_CTRL_BPF		  (0x1 << 27) /* BPF offload capable */
 #define   NFP_NET_CFG_CTRL_LSO2		  (0x1 << 28) /* LSO/TSO (version 2) */
+#define   NFP_NET_CFG_CTRL_RSS2		  (0x1 << 29) /* RSS (version 2) */
 
 #define NFP_NET_CFG_CTRL_LSO_ANY	(NFP_NET_CFG_CTRL_LSO | \
 					 NFP_NET_CFG_CTRL_LSO2)
+#define NFP_NET_CFG_CTRL_RSS_ANY	(NFP_NET_CFG_CTRL_RSS | \
+					 NFP_NET_CFG_CTRL_RSS2)
+#define NFP_NET_CFG_CTRL_CHAIN_META	NFP_NET_CFG_CTRL_RSS2
 
 #define NFP_NET_CFG_UPDATE              0x0004
 #define   NFP_NET_CFG_UPDATE_GEN          (0x1 <<  0) /* General update */
diff --git a/drivers/net/ethernet/netronome/nfp/nfp_net_ethtool.c b/drivers/net/ethernet/netronome/nfp/nfp_net_ethtool.c
index abbb47e60cc3..70bb0a0152b9 100644
--- a/drivers/net/ethernet/netronome/nfp/nfp_net_ethtool.c
+++ b/drivers/net/ethernet/netronome/nfp/nfp_net_ethtool.c
@@ -496,7 +496,7 @@ static int nfp_net_get_rss_hash_opts(struct nfp_net *nn,
 
 	cmd->data = 0;
 
-	if (!(nn->cap & NFP_NET_CFG_CTRL_RSS))
+	if (!(nn->cap & NFP_NET_CFG_CTRL_RSS_ANY))
 		return -EOPNOTSUPP;
 
 	nfp_rss_flag = ethtool_flow_to_nfp_flag(cmd->flow_type);
@@ -533,7 +533,7 @@ static int nfp_net_set_rss_hash_opt(struct nfp_net *nn,
 	u32 nfp_rss_flag;
 	int err;
 
-	if (!(nn->cap & NFP_NET_CFG_CTRL_RSS))
+	if (!(nn->cap & NFP_NET_CFG_CTRL_RSS_ANY))
 		return -EOPNOTSUPP;
 
 	/* RSS only supports IP SA/DA and L4 src/dst ports  */
@@ -595,7 +595,7 @@ static u32 nfp_net_get_rxfh_indir_size(struct net_device *netdev)
 {
 	struct nfp_net *nn = netdev_priv(netdev);
 
-	if (!(nn->cap & NFP_NET_CFG_CTRL_RSS))
+	if (!(nn->cap & NFP_NET_CFG_CTRL_RSS_ANY))
 		return 0;
 
 	return ARRAY_SIZE(nn->rss_itbl);
@@ -605,7 +605,7 @@ static u32 nfp_net_get_rxfh_key_size(struct net_device *netdev)
 {
 	struct nfp_net *nn = netdev_priv(netdev);
 
-	if (!(nn->cap & NFP_NET_CFG_CTRL_RSS))
+	if (!(nn->cap & NFP_NET_CFG_CTRL_RSS_ANY))
 		return -EOPNOTSUPP;
 
 	return nfp_net_rss_key_sz(nn);
@@ -617,7 +617,7 @@ static int nfp_net_get_rxfh(struct net_device *netdev, u32 *indir, u8 *key,
 	struct nfp_net *nn = netdev_priv(netdev);
 	int i;
 
-	if (!(nn->cap & NFP_NET_CFG_CTRL_RSS))
+	if (!(nn->cap & NFP_NET_CFG_CTRL_RSS_ANY))
 		return -EOPNOTSUPP;
 
 	if (indir)
@@ -641,7 +641,7 @@ static int nfp_net_set_rxfh(struct net_device *netdev,
 	struct nfp_net *nn = netdev_priv(netdev);
 	int i;
 
-	if (!(nn->cap & NFP_NET_CFG_CTRL_RSS) ||
+	if (!(nn->cap & NFP_NET_CFG_CTRL_RSS_ANY) ||
 	    !(hfunc == ETH_RSS_HASH_NO_CHANGE || hfunc == nn->rss_hfunc))
 		return -EOPNOTSUPP;
 
-- 
2.11.0

[PATCH net-next 6/9] nfp: add CHECKSUM_COMPLETE support

[Jakub Kicinski]

Introduce NFP_NET_CFG_CTRL_CSUM_COMPLETE capability and implement parsing
of CHECKSUM_COMPLETE metadata.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Edwin Peer <edwin.peer@netronome.com>
Reviewed-by: Simon Horman <simon.horman@netronome.com>
---
 drivers/net/ethernet/netronome/nfp/nfp_net.h       |  4 ++-
 .../net/ethernet/netronome/nfp/nfp_net_common.c    | 35 +++++++++++++++++-----
 drivers/net/ethernet/netronome/nfp/nfp_net_ctrl.h  |  7 ++++-
 3 files changed, 36 insertions(+), 10 deletions(-)

diff --git a/drivers/net/ethernet/netronome/nfp/nfp_net.h b/drivers/net/ethernet/netronome/nfp/nfp_net.h
index c6b7141dc50d..acd9811d08d1 100644
--- a/drivers/net/ethernet/netronome/nfp/nfp_net.h
+++ b/drivers/net/ethernet/netronome/nfp/nfp_net.h
@@ -292,9 +292,11 @@ struct nfp_net_rx_desc {
 #define NFP_NET_META_FIELD_MASK GENMASK(NFP_NET_META_FIELD_SIZE - 1, 0)
 
 struct nfp_meta_parsed {
-	u32 hash_type;
+	u8 hash_type;
+	u8 csum_type;
 	u32 hash;
 	u32 mark;
+	__wsum csum;
 };
 
 struct nfp_net_rx_hash {
diff --git a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
index cc5a2eaef156..d640b3331741 100644
--- a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
+++ b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
@@ -1354,17 +1354,28 @@ static int nfp_net_rx_csum_has_errors(u16 flags)
  * @dp:  NFP Net data path struct
  * @r_vec: per-ring structure
  * @rxd: Pointer to RX descriptor
+ * @meta: Parsed metadata prepend
  * @skb: Pointer to SKB
  */
 static void nfp_net_rx_csum(struct nfp_net_dp *dp,
 			    struct nfp_net_r_vector *r_vec,
-			    struct nfp_net_rx_desc *rxd, struct sk_buff *skb)
+			    struct nfp_net_rx_desc *rxd,
+			    struct nfp_meta_parsed *meta, struct sk_buff *skb)
 {
 	skb_checksum_none_assert(skb);
 
 	if (!(dp->netdev->features & NETIF_F_RXCSUM))
 		return;
 
+	if (meta->csum_type) {
+		skb->ip_summed = meta->csum_type;
+		skb->csum = meta->csum;
+		u64_stats_update_begin(&r_vec->rx_sync);
+		r_vec->hw_csum_rx_ok++;
+		u64_stats_update_end(&r_vec->rx_sync);
+		return;
+	}
+
 	if (nfp_net_rx_csum_has_errors(le16_to_cpu(rxd->rxd.flags))) {
 		u64_stats_update_begin(&r_vec->rx_sync);
 		r_vec->hw_csum_rx_error++;
@@ -1449,6 +1460,12 @@ nfp_net_parse_meta(struct net_device *netdev, struct nfp_meta_parsed *meta,
 			meta->mark = get_unaligned_be32(data);
 			data += 4;
 			break;
+		case NFP_NET_META_CSUM:
+			meta->csum_type = CHECKSUM_COMPLETE;
+			meta->csum =
+				(__force __wsum)__get_unaligned_cpu32(data);
+			data += 4;
+			break;
 		default:
 			return NULL;
 		}
@@ -1712,7 +1729,7 @@ static int nfp_net_rx(struct nfp_net_rx_ring *rx_ring, int budget)
 		skb_record_rx_queue(skb, rx_ring->idx);
 		skb->protocol = eth_type_trans(skb, dp->netdev);
 
-		nfp_net_rx_csum(dp, r_vec, rxd, skb);
+		nfp_net_rx_csum(dp, r_vec, rxd, &meta, skb);
 
 		if (rxd->rxd.flags & PCIE_DESC_RX_VLAN)
 			__vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q),
@@ -2712,9 +2729,9 @@ static int nfp_net_set_features(struct net_device *netdev,
 
 	if (changed & NETIF_F_RXCSUM) {
 		if (features & NETIF_F_RXCSUM)
-			new_ctrl |= NFP_NET_CFG_CTRL_RXCSUM;
+			new_ctrl |= nn->cap & NFP_NET_CFG_CTRL_RXCSUM_ANY;
 		else
-			new_ctrl &= ~NFP_NET_CFG_CTRL_RXCSUM;
+			new_ctrl &= ~NFP_NET_CFG_CTRL_RXCSUM_ANY;
 	}
 
 	if (changed & (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM)) {
@@ -3035,7 +3052,7 @@ void nfp_net_info(struct nfp_net *nn)
 		nn->fw_ver.resv, nn->fw_ver.class,
 		nn->fw_ver.major, nn->fw_ver.minor,
 		nn->max_mtu);
-	nn_info(nn, "CAP: %#x %s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s\n",
+	nn_info(nn, "CAP: %#x %s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s\n",
 		nn->cap,
 		nn->cap & NFP_NET_CFG_CTRL_PROMISC  ? "PROMISC "  : "",
 		nn->cap & NFP_NET_CFG_CTRL_L2BC     ? "L2BCFILT " : "",
@@ -3055,7 +3072,9 @@ void nfp_net_info(struct nfp_net *nn)
 		nn->cap & NFP_NET_CFG_CTRL_IRQMOD   ? "IRQMOD "   : "",
 		nn->cap & NFP_NET_CFG_CTRL_VXLAN    ? "VXLAN "    : "",
 		nn->cap & NFP_NET_CFG_CTRL_NVGRE    ? "NVGRE "	  : "",
-		nfp_net_ebpf_capable(nn)            ? "BPF "	  : "");
+		nfp_net_ebpf_capable(nn)            ? "BPF "	  : "",
+		nn->cap & NFP_NET_CFG_CTRL_CSUM_COMPLETE ?
+						      "RXCSUM_COMPLETE " : "");
 }
 
 /**
@@ -3246,9 +3265,9 @@ int nfp_net_netdev_init(struct net_device *netdev)
 	 * supported.  By default we enable most features.
 	 */
 	netdev->hw_features = NETIF_F_HIGHDMA;
-	if (nn->cap & NFP_NET_CFG_CTRL_RXCSUM) {
+	if (nn->cap & NFP_NET_CFG_CTRL_RXCSUM_ANY) {
 		netdev->hw_features |= NETIF_F_RXCSUM;
-		nn->dp.ctrl |= NFP_NET_CFG_CTRL_RXCSUM;
+		nn->dp.ctrl |= nn->cap & NFP_NET_CFG_CTRL_RXCSUM_ANY;
 	}
 	if (nn->cap & NFP_NET_CFG_CTRL_TXCSUM) {
 		netdev->hw_features |= NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM;
diff --git a/drivers/net/ethernet/netronome/nfp/nfp_net_ctrl.h b/drivers/net/ethernet/netronome/nfp/nfp_net_ctrl.h
index a049c5d6839d..df75b8dc3617 100644
--- a/drivers/net/ethernet/netronome/nfp/nfp_net_ctrl.h
+++ b/drivers/net/ethernet/netronome/nfp/nfp_net_ctrl.h
@@ -71,6 +71,7 @@
 #define NFP_NET_META_FIELD_SIZE		4
 #define NFP_NET_META_HASH		1 /* next field carries hash type */
 #define NFP_NET_META_MARK		2
+#define NFP_NET_META_CSUM		6 /* checksum complete type */
 
 /**
  * Hash type pre-pended when a RSS hash was computed
@@ -133,12 +134,16 @@
 #define   NFP_NET_CFG_CTRL_BPF		  (0x1 << 27) /* BPF offload capable */
 #define   NFP_NET_CFG_CTRL_LSO2		  (0x1 << 28) /* LSO/TSO (version 2) */
 #define   NFP_NET_CFG_CTRL_RSS2		  (0x1 << 29) /* RSS (version 2) */
+#define   NFP_NET_CFG_CTRL_CSUM_COMPLETE  (0x1 << 30) /* Checksum complete */
 
 #define NFP_NET_CFG_CTRL_LSO_ANY	(NFP_NET_CFG_CTRL_LSO | \
 					 NFP_NET_CFG_CTRL_LSO2)
 #define NFP_NET_CFG_CTRL_RSS_ANY	(NFP_NET_CFG_CTRL_RSS | \
 					 NFP_NET_CFG_CTRL_RSS2)
-#define NFP_NET_CFG_CTRL_CHAIN_META	NFP_NET_CFG_CTRL_RSS2
+#define NFP_NET_CFG_CTRL_RXCSUM_ANY	(NFP_NET_CFG_CTRL_RXCSUM | \
+					 NFP_NET_CFG_CTRL_CSUM_COMPLETE)
+#define NFP_NET_CFG_CTRL_CHAIN_META	(NFP_NET_CFG_CTRL_RSS2 | \
+					 NFP_NET_CFG_CTRL_CSUM_COMPLETE)
 
 #define NFP_NET_CFG_UPDATE              0x0004
 #define   NFP_NET_CFG_UPDATE_GEN          (0x1 <<  0) /* General update */
-- 
2.11.0

[PATCH net-next 7/9] nfp: complete the XDP TX ring only when it's full

[Jakub Kicinski]

Since XDP TX ring holds "spare" RX buffers anyway, we don't have to
rush the completion.  We can wait until ring fills up completely
before trying to reclaim buffers.  If RX poll has ended an no
buffer has been queued for XDP TX we have no guarantee we will see
another interrupt, so run the reclaim there as well, to make sure
TX statistics won't become stale.

This should help us reclaim more buffers per single queue controller
register read.

Note that the XDP completion is very trivial, it only adds up
the sizes of transmitted frames for statistics so the latency
spike should be acceptable.  In case user sets the ring sizes
to something crazy, limit the completion to 2k entries.

The check if the ring is empty at the beginning of xdp_complete()
is no longer needed - the callers will perform it.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
---
 drivers/net/ethernet/netronome/nfp/nfp_net.h       |  1 +
 .../net/ethernet/netronome/nfp/nfp_net_common.c    | 52 ++++++++++++++--------
 2 files changed, 35 insertions(+), 18 deletions(-)

diff --git a/drivers/net/ethernet/netronome/nfp/nfp_net.h b/drivers/net/ethernet/netronome/nfp/nfp_net.h
index acd9811d08d1..66319a1026bb 100644
--- a/drivers/net/ethernet/netronome/nfp/nfp_net.h
+++ b/drivers/net/ethernet/netronome/nfp/nfp_net.h
@@ -102,6 +102,7 @@
 #define NFP_NET_RX_DESCS_DEFAULT 4096	/* Default # of Rx descs per ring */
 
 #define NFP_NET_FL_BATCH	16	/* Add freelist in this Batch size */
+#define NFP_NET_XDP_MAX_COMPLETE 2048	/* XDP bufs to reclaim in NAPI poll */
 
 /* Offload definitions */
 #define NFP_NET_N_VXLAN_PORTS	(NFP_NET_CFG_VXLAN_SZ / sizeof(__be16))
diff --git a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
index d640b3331741..a4c6878f1df1 100644
--- a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
+++ b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
@@ -1001,27 +1001,30 @@ static void nfp_net_tx_complete(struct nfp_net_tx_ring *tx_ring)
 		  tx_ring->rd_p, tx_ring->wr_p, tx_ring->cnt);
 }
 
-static void nfp_net_xdp_complete(struct nfp_net_tx_ring *tx_ring)
+static bool nfp_net_xdp_complete(struct nfp_net_tx_ring *tx_ring)
 {
 	struct nfp_net_r_vector *r_vec = tx_ring->r_vec;
 	u32 done_pkts = 0, done_bytes = 0;
+	bool done_all;
 	int idx, todo;
 	u32 qcp_rd_p;
 
-	if (tx_ring->wr_p == tx_ring->rd_p)
-		return;
-
 	/* Work out how many descriptors have been transmitted */
 	qcp_rd_p = nfp_qcp_rd_ptr_read(tx_ring->qcp_q);
 
 	if (qcp_rd_p == tx_ring->qcp_rd_p)
-		return;
+		return true;
 
 	if (qcp_rd_p > tx_ring->qcp_rd_p)
 		todo = qcp_rd_p - tx_ring->qcp_rd_p;
 	else
 		todo = qcp_rd_p + tx_ring->cnt - tx_ring->qcp_rd_p;
 
+	done_all = todo <= NFP_NET_XDP_MAX_COMPLETE;
+	todo = min(todo, NFP_NET_XDP_MAX_COMPLETE);
+
+	tx_ring->qcp_rd_p = (tx_ring->qcp_rd_p + todo) & (tx_ring->cnt - 1);
+
 	done_pkts = todo;
 	while (todo--) {
 		idx = tx_ring->rd_p & (tx_ring->cnt - 1);
@@ -1030,16 +1033,16 @@ static void nfp_net_xdp_complete(struct nfp_net_tx_ring *tx_ring)
 		done_bytes += tx_ring->txbufs[idx].real_len;
 	}
 
-	tx_ring->qcp_rd_p = qcp_rd_p;
-
 	u64_stats_update_begin(&r_vec->tx_sync);
 	r_vec->tx_bytes += done_bytes;
 	r_vec->tx_pkts += done_pkts;
 	u64_stats_update_end(&r_vec->tx_sync);
 
 	WARN_ONCE(tx_ring->wr_p - tx_ring->rd_p > tx_ring->cnt,
-		  "TX ring corruption rd_p=%u wr_p=%u cnt=%u\n",
+		  "XDP TX ring corruption rd_p=%u wr_p=%u cnt=%u\n",
 		  tx_ring->rd_p, tx_ring->wr_p, tx_ring->cnt);
+
+	return done_all;
 }
 
 /**
@@ -1500,15 +1503,23 @@ static bool
 nfp_net_tx_xdp_buf(struct nfp_net_dp *dp, struct nfp_net_rx_ring *rx_ring,
 		   struct nfp_net_tx_ring *tx_ring,
 		   struct nfp_net_rx_buf *rxbuf, unsigned int dma_off,
-		   unsigned int pkt_len)
+		   unsigned int pkt_len, bool *completed)
 {
 	struct nfp_net_tx_buf *txbuf;
 	struct nfp_net_tx_desc *txd;
 	int wr_idx;
 
 	if (unlikely(nfp_net_tx_full(tx_ring, 1))) {
-		nfp_net_rx_drop(dp, rx_ring->r_vec, rx_ring, rxbuf, NULL);
-		return false;
+		if (!*completed) {
+			nfp_net_xdp_complete(tx_ring);
+			*completed = true;
+		}
+
+		if (unlikely(nfp_net_tx_full(tx_ring, 1))) {
+			nfp_net_rx_drop(dp, rx_ring->r_vec, rx_ring, rxbuf,
+					NULL);
+			return false;
+		}
 	}
 
 	wr_idx = tx_ring->wr_p & (tx_ring->cnt - 1);
@@ -1580,6 +1591,7 @@ static int nfp_net_rx(struct nfp_net_rx_ring *rx_ring, int budget)
 	struct nfp_net_dp *dp = &r_vec->nfp_net->dp;
 	struct nfp_net_tx_ring *tx_ring;
 	struct bpf_prog *xdp_prog;
+	bool xdp_tx_cmpl = false;
 	unsigned int true_bufsz;
 	struct sk_buff *skb;
 	int pkts_polled = 0;
@@ -1690,7 +1702,8 @@ static int nfp_net_rx(struct nfp_net_rx_ring *rx_ring, int budget)
 				if (unlikely(!nfp_net_tx_xdp_buf(dp, rx_ring,
 								 tx_ring, rxbuf,
 								 dma_off,
-								 pkt_len)))
+								 pkt_len,
+								 &xdp_tx_cmpl)))
 					trace_xdp_exception(dp->netdev,
 							    xdp_prog, act);
 				continue;
@@ -1738,8 +1751,14 @@ static int nfp_net_rx(struct nfp_net_rx_ring *rx_ring, int budget)
 		napi_gro_receive(&rx_ring->r_vec->napi, skb);
 	}
 
-	if (xdp_prog && tx_ring->wr_ptr_add)
-		nfp_net_tx_xmit_more_flush(tx_ring);
+	if (xdp_prog) {
+		if (tx_ring->wr_ptr_add)
+			nfp_net_tx_xmit_more_flush(tx_ring);
+		else if (unlikely(tx_ring->wr_p != tx_ring->rd_p) &&
+			 !xdp_tx_cmpl)
+			if (!nfp_net_xdp_complete(tx_ring))
+				pkts_polled = budget;
+	}
 	rcu_read_unlock();
 
 	return pkts_polled;
@@ -1760,11 +1779,8 @@ static int nfp_net_poll(struct napi_struct *napi, int budget)
 
 	if (r_vec->tx_ring)
 		nfp_net_tx_complete(r_vec->tx_ring);
-	if (r_vec->rx_ring) {
+	if (r_vec->rx_ring)
 		pkts_polled = nfp_net_rx(r_vec->rx_ring, budget);
-		if (r_vec->xdp_ring)
-			nfp_net_xdp_complete(r_vec->xdp_ring);
-	}
 
 	if (pkts_polled < budget)
 		if (napi_complete_done(napi, pkts_polled))
-- 
2.11.0

[PATCH net-next 8/9] nfp: add a helper for wrapping descriptor index

[Jakub Kicinski]

We have a number of places where we calculate the descriptor
index based on a value which may have overflown.  Create a
macro for masking with the ring size.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
---
 drivers/net/ethernet/netronome/nfp/nfp_net.h        |  3 +++
 drivers/net/ethernet/netronome/nfp/nfp_net_common.c | 21 ++++++++++-----------
 2 files changed, 13 insertions(+), 11 deletions(-)

diff --git a/drivers/net/ethernet/netronome/nfp/nfp_net.h b/drivers/net/ethernet/netronome/nfp/nfp_net.h
index 66319a1026bb..7b9518cbe965 100644
--- a/drivers/net/ethernet/netronome/nfp/nfp_net.h
+++ b/drivers/net/ethernet/netronome/nfp/nfp_net.h
@@ -117,6 +117,9 @@ struct nfp_eth_table_port;
 struct nfp_net;
 struct nfp_net_r_vector;
 
+/* Convenience macro for wrapping descriptor index on ring size */
+#define D_IDX(ring, idx)	((idx) & ((ring)->cnt - 1))
+
 /* Convenience macro for writing dma address into RX/TX descriptors */
 #define nfp_desc_set_dma_addr(desc, dma_addr)				\
 	do {								\
diff --git a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
index a4c6878f1df1..c64514f8ee65 100644
--- a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
+++ b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
@@ -809,7 +809,7 @@ static int nfp_net_tx(struct sk_buff *skb, struct net_device *netdev)
 	if (dma_mapping_error(dp->dev, dma_addr))
 		goto err_free;
 
-	wr_idx = tx_ring->wr_p & (tx_ring->cnt - 1);
+	wr_idx = D_IDX(tx_ring, tx_ring->wr_p);
 
 	/* Stash the soft descriptor of the head then initialize it */
 	txbuf = &tx_ring->txbufs[wr_idx];
@@ -852,7 +852,7 @@ static int nfp_net_tx(struct sk_buff *skb, struct net_device *netdev)
 			if (dma_mapping_error(dp->dev, dma_addr))
 				goto err_unmap;
 
-			wr_idx = (wr_idx + 1) & (tx_ring->cnt - 1);
+			wr_idx = D_IDX(tx_ring, wr_idx + 1);
 			tx_ring->txbufs[wr_idx].skb = skb;
 			tx_ring->txbufs[wr_idx].dma_addr = dma_addr;
 			tx_ring->txbufs[wr_idx].fidx = f;
@@ -946,8 +946,7 @@ static void nfp_net_tx_complete(struct nfp_net_tx_ring *tx_ring)
 		todo = qcp_rd_p + tx_ring->cnt - tx_ring->qcp_rd_p;
 
 	while (todo--) {
-		idx = tx_ring->rd_p & (tx_ring->cnt - 1);
-		tx_ring->rd_p++;
+		idx = D_IDX(tx_ring, tx_ring->rd_p++);
 
 		skb = tx_ring->txbufs[idx].skb;
 		if (!skb)
@@ -1023,11 +1022,11 @@ static bool nfp_net_xdp_complete(struct nfp_net_tx_ring *tx_ring)
 	done_all = todo <= NFP_NET_XDP_MAX_COMPLETE;
 	todo = min(todo, NFP_NET_XDP_MAX_COMPLETE);
 
-	tx_ring->qcp_rd_p = (tx_ring->qcp_rd_p + todo) & (tx_ring->cnt - 1);
+	tx_ring->qcp_rd_p = D_IDX(tx_ring, tx_ring->qcp_rd_p + todo);
 
 	done_pkts = todo;
 	while (todo--) {
-		idx = tx_ring->rd_p & (tx_ring->cnt - 1);
+		idx = D_IDX(tx_ring, tx_ring->rd_p);
 		tx_ring->rd_p++;
 
 		done_bytes += tx_ring->txbufs[idx].real_len;
@@ -1063,7 +1062,7 @@ nfp_net_tx_ring_reset(struct nfp_net_dp *dp, struct nfp_net_tx_ring *tx_ring)
 		struct sk_buff *skb;
 		int idx, nr_frags;
 
-		idx = tx_ring->rd_p & (tx_ring->cnt - 1);
+		idx = D_IDX(tx_ring, tx_ring->rd_p);
 		tx_buf = &tx_ring->txbufs[idx];
 
 		skb = tx_ring->txbufs[idx].skb;
@@ -1216,7 +1215,7 @@ static void nfp_net_rx_give_one(const struct nfp_net_dp *dp,
 {
 	unsigned int wr_idx;
 
-	wr_idx = rx_ring->wr_p & (rx_ring->cnt - 1);
+	wr_idx = D_IDX(rx_ring, rx_ring->wr_p);
 
 	nfp_net_dma_sync_dev_rx(dp, dma_addr);
 
@@ -1254,7 +1253,7 @@ static void nfp_net_rx_ring_reset(struct nfp_net_rx_ring *rx_ring)
 	unsigned int wr_idx, last_idx;
 
 	/* Move the empty entry to the end of the list */
-	wr_idx = rx_ring->wr_p & (rx_ring->cnt - 1);
+	wr_idx = D_IDX(rx_ring, rx_ring->wr_p);
 	last_idx = rx_ring->cnt - 1;
 	rx_ring->rxbufs[wr_idx].dma_addr = rx_ring->rxbufs[last_idx].dma_addr;
 	rx_ring->rxbufs[wr_idx].frag = rx_ring->rxbufs[last_idx].frag;
@@ -1522,7 +1521,7 @@ nfp_net_tx_xdp_buf(struct nfp_net_dp *dp, struct nfp_net_rx_ring *rx_ring,
 		}
 	}
 
-	wr_idx = tx_ring->wr_p & (tx_ring->cnt - 1);
+	wr_idx = D_IDX(tx_ring, tx_ring->wr_p);
 
 	/* Stash the soft descriptor of the head then initialize it */
 	txbuf = &tx_ring->txbufs[wr_idx];
@@ -1610,7 +1609,7 @@ static int nfp_net_rx(struct nfp_net_rx_ring *rx_ring, int budget)
 		dma_addr_t new_dma_addr;
 		void *new_frag;
 
-		idx = rx_ring->rd_p & (rx_ring->cnt - 1);
+		idx = D_IDX(rx_ring, rx_ring->rd_p);
 
 		rxd = &rx_ring->rxds[idx];
 		if (!(rxd->rxd.meta_len_dd & PCIE_DESC_RX_DD))
-- 
2.11.0

[PATCH net-next 9/9] nfp: eliminate an if statement in calculation of completed frames

[Jakub Kicinski]

Given that our rings are always a power of 2, we can simplify the
calculation of number of completed TX descriptors by using masking
instead of if statement based on whether the index have wrapped
or not.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
---
 drivers/net/ethernet/netronome/nfp/nfp_net_common.c | 10 ++--------
 1 file changed, 2 insertions(+), 8 deletions(-)

diff --git a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
index c64514f8ee65..da83e17b8b20 100644
--- a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
+++ b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
@@ -940,10 +940,7 @@ static void nfp_net_tx_complete(struct nfp_net_tx_ring *tx_ring)
 	if (qcp_rd_p == tx_ring->qcp_rd_p)
 		return;
 
-	if (qcp_rd_p > tx_ring->qcp_rd_p)
-		todo = qcp_rd_p - tx_ring->qcp_rd_p;
-	else
-		todo = qcp_rd_p + tx_ring->cnt - tx_ring->qcp_rd_p;
+	todo = D_IDX(tx_ring, qcp_rd_p + tx_ring->cnt - tx_ring->qcp_rd_p);
 
 	while (todo--) {
 		idx = D_IDX(tx_ring, tx_ring->rd_p++);
@@ -1014,10 +1011,7 @@ static bool nfp_net_xdp_complete(struct nfp_net_tx_ring *tx_ring)
 	if (qcp_rd_p == tx_ring->qcp_rd_p)
 		return true;
 
-	if (qcp_rd_p > tx_ring->qcp_rd_p)
-		todo = qcp_rd_p - tx_ring->qcp_rd_p;
-	else
-		todo = qcp_rd_p + tx_ring->cnt - tx_ring->qcp_rd_p;
+	todo = D_IDX(tx_ring, qcp_rd_p + tx_ring->cnt - tx_ring->qcp_rd_p);
 
 	done_all = todo <= NFP_NET_XDP_MAX_COMPLETE;
 	todo = min(todo, NFP_NET_XDP_MAX_COMPLETE);
-- 
2.11.0

Re: [oss-drivers] [PATCH net-next 3/9] nfp: support LSO2 capability

[Simon Horman]

On Mon, May 15, 2017 at 05:55:17PM -0700, Jakub Kicinski wrote:
> From: Edwin Peer <edwin.peer@netronome.com>
> 
> Firmware advertising the LSO2 capability exploits driver provided L3 and L4
> offsets in order to avoid parsing packet headers in the TX path. The vlan
> field in struct nfp_net_tx_desc is repurposed, making TXVLAN a mutually
> exclusive configuration to LSO2.
> 
> Signed-off-by: Edwin Peer <edwin.peer@netronome.com>
> Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>

Reviewed-by: Simon Horman <simon.horman@netronome.com>

Re: [oss-drivers] [PATCH net-next 9/9] nfp: eliminate an if statement in calculation of completed frames

[Simon Horman]

On Mon, May 15, 2017 at 05:55:23PM -0700, Jakub Kicinski wrote:
> Given that our rings are always a power of 2, we can simplify the
> calculation of number of completed TX descriptors by using masking
> instead of if statement based on whether the index have wrapped
> or not.
> 
> Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>

Reviewed-by: Simon Horman <simon.horman@netronome.com>

Re: [oss-drivers] [PATCH net-next 8/9] nfp: add a helper for wrapping descriptor index

[Simon Horman]

On Mon, May 15, 2017 at 05:55:22PM -0700, Jakub Kicinski wrote:
> We have a number of places where we calculate the descriptor
> index based on a value which may have overflown.  Create a
> macro for masking with the ring size.
> 
> Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
> ---
>  drivers/net/ethernet/netronome/nfp/nfp_net.h        |  3 +++
>  drivers/net/ethernet/netronome/nfp/nfp_net_common.c | 21 ++++++++++-----------
>  2 files changed, 13 insertions(+), 11 deletions(-)
> 
> diff --git a/drivers/net/ethernet/netronome/nfp/nfp_net.h b/drivers/net/ethernet/netronome/nfp/nfp_net.h
> index 66319a1026bb..7b9518cbe965 100644
> --- a/drivers/net/ethernet/netronome/nfp/nfp_net.h
> +++ b/drivers/net/ethernet/netronome/nfp/nfp_net.h
> @@ -117,6 +117,9 @@ struct nfp_eth_table_port;
>  struct nfp_net;
>  struct nfp_net_r_vector;
>  
> +/* Convenience macro for wrapping descriptor index on ring size */
> +#define D_IDX(ring, idx)	((idx) & ((ring)->cnt - 1))

Any reason not to make this a function?

That notwithstanding:

Reviewed-by: Simon Horman <simon.horman@netronome.com>

Re: [oss-drivers] [PATCH net-next 8/9] nfp: add a helper for wrapping descriptor index

[Jakub Kicinski]

On Tue, 16 May 2017 09:08:08 +0200, Simon Horman wrote:
> On Mon, May 15, 2017 at 05:55:22PM -0700, Jakub Kicinski wrote:
> > We have a number of places where we calculate the descriptor
> > index based on a value which may have overflown.  Create a
> > macro for masking with the ring size.
> > 
> > Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
> > ---
> >  drivers/net/ethernet/netronome/nfp/nfp_net.h        |  3 +++
> >  drivers/net/ethernet/netronome/nfp/nfp_net_common.c | 21 ++++++++++-----------
> >  2 files changed, 13 insertions(+), 11 deletions(-)
> > 
> > diff --git a/drivers/net/ethernet/netronome/nfp/nfp_net.h b/drivers/net/ethernet/netronome/nfp/nfp_net.h
> > index 66319a1026bb..7b9518cbe965 100644
> > --- a/drivers/net/ethernet/netronome/nfp/nfp_net.h
> > +++ b/drivers/net/ethernet/netronome/nfp/nfp_net.h
> > @@ -117,6 +117,9 @@ struct nfp_eth_table_port;
> >  struct nfp_net;
> >  struct nfp_net_r_vector;
> >  
> > +/* Convenience macro for wrapping descriptor index on ring size */
> > +#define D_IDX(ring, idx)	((idx) & ((ring)->cnt - 1))  
> 
> Any reason not to make this a function?

This is to be able to use the same macro for both RX and TX rings.  If
you look below in the code I have a macro for setting dma addresses on
descriptors also regardless of the type.

It makes the code a tiny bit cleaner IMHO and should be acceptable for
trivial macros.

> That notwithstanding:
> 
> Reviewed-by: Simon Horman <simon.horman@netronome.com>

Thanks for the reviews!

Re: [oss-drivers] [PATCH net-next 8/9] nfp: add a helper for wrapping descriptor index

[Simon Horman]

On Tue, May 16, 2017 at 12:38:57AM -0700, Jakub Kicinski wrote:
> On Tue, 16 May 2017 09:08:08 +0200, Simon Horman wrote:
> > On Mon, May 15, 2017 at 05:55:22PM -0700, Jakub Kicinski wrote:
> > > We have a number of places where we calculate the descriptor
> > > index based on a value which may have overflown.  Create a
> > > macro for masking with the ring size.
> > > 
> > > Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
> > > ---
> > >  drivers/net/ethernet/netronome/nfp/nfp_net.h        |  3 +++
> > >  drivers/net/ethernet/netronome/nfp/nfp_net_common.c | 21 ++++++++++-----------
> > >  2 files changed, 13 insertions(+), 11 deletions(-)
> > > 
> > > diff --git a/drivers/net/ethernet/netronome/nfp/nfp_net.h b/drivers/net/ethernet/netronome/nfp/nfp_net.h
> > > index 66319a1026bb..7b9518cbe965 100644
> > > --- a/drivers/net/ethernet/netronome/nfp/nfp_net.h
> > > +++ b/drivers/net/ethernet/netronome/nfp/nfp_net.h
> > > @@ -117,6 +117,9 @@ struct nfp_eth_table_port;
> > >  struct nfp_net;
> > >  struct nfp_net_r_vector;
> > >  
> > > +/* Convenience macro for wrapping descriptor index on ring size */
> > > +#define D_IDX(ring, idx)	((idx) & ((ring)->cnt - 1))  
> > 
> > Any reason not to make this a function?
> 
> This is to be able to use the same macro for both RX and TX rings.  If
> you look below in the code I have a macro for setting dma addresses on
> descriptors also regardless of the type.
> 
> It makes the code a tiny bit cleaner IMHO and should be acceptable for
> trivial macros.

Thanks for the clarification, that sounds reasonable to me.

> > That notwithstanding:
> > 
> > Reviewed-by: Simon Horman <simon.horman@netronome.com>
> 
> Thanks for the reviews!

Re: [PATCH net-next 0/9] nfp: LSO, checksum and XDP datapath updates

[David Miller]

From: Jakub Kicinski <jakub.kicinski@netronome.com>
Date: Mon, 15 May 2017 17:55:14 -0700

> This series introduces a number of refinements to standard features
> like LSO and checksum offload.  Three major features are support for
> CHECKSUM_COMPLETE, refinement of TSO handling and another small speed
> up for XDP TX.  This series also switches from depending on some 
> app FW<>driver ABI versions to heavier use of capabilities.

Series applied, thanks Jakub.

RE: [PATCH net-next 9/9] nfp: eliminate an if statement in calculation of completed frames

[David Laight]

From: Jakub Kicinski
> Sent: 16 May 2017 01:55
> Given that our rings are always a power of 2, we can simplify the
> calculation of number of completed TX descriptors by using masking
> instead of if statement based on whether the index have wrapped
> or not.
> 
> Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
> ---
>  drivers/net/ethernet/netronome/nfp/nfp_net_common.c | 10 ++--------
>  1 file changed, 2 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
> b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
> index c64514f8ee65..da83e17b8b20 100644
> --- a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
> +++ b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
> @@ -940,10 +940,7 @@ static void nfp_net_tx_complete(struct nfp_net_tx_ring *tx_ring)
>  	if (qcp_rd_p == tx_ring->qcp_rd_p)
>  		return;
> 
> -	if (qcp_rd_p > tx_ring->qcp_rd_p)
> -		todo = qcp_rd_p - tx_ring->qcp_rd_p;
> -	else
> -		todo = qcp_rd_p + tx_ring->cnt - tx_ring->qcp_rd_p;
> +	todo = D_IDX(tx_ring, qcp_rd_p + tx_ring->cnt - tx_ring->qcp_rd_p);

I'm not sure you need to add tx_ring->cnt here.
I bet D_IDX() masks it away.

>  	while (todo--) {
>  		idx = D_IDX(tx_ring, tx_ring->rd_p++);

That '++' looks suspicious.
I think you need to decide whether you are incrementing pointers into the ring
or indexes into it.
Sometimes it is safer to use a non-wrapping index and mask when accessing the entry.
	entry_ptr = &ring[idx & (RING_SIZE - 1)]
Ring full is then (read_idx == write_idx + RING_SIZE),
ring empty (read_idx == write_idx).
So the index just wrap at (probably)_2^32.

	David

Re: [PATCH net-next 9/9] nfp: eliminate an if statement in calculation of completed frames

[Jakub Kicinski]

On Wed, 17 May 2017 11:07:19 +0000, David Laight wrote:
> From: Jakub Kicinski
> > Sent: 16 May 2017 01:55
> > Given that our rings are always a power of 2, we can simplify the
> > calculation of number of completed TX descriptors by using masking
> > instead of if statement based on whether the index have wrapped
> > or not.
> > 
> > Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
> > ---
> >  drivers/net/ethernet/netronome/nfp/nfp_net_common.c | 10 ++--------
> >  1 file changed, 2 insertions(+), 8 deletions(-)
> > 
> > diff --git a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
> > b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
> > index c64514f8ee65..da83e17b8b20 100644
> > --- a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
> > +++ b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
> > @@ -940,10 +940,7 @@ static void nfp_net_tx_complete(struct nfp_net_tx_ring *tx_ring)
> >  	if (qcp_rd_p == tx_ring->qcp_rd_p)
> >  		return;
> > 
> > -	if (qcp_rd_p > tx_ring->qcp_rd_p)
> > -		todo = qcp_rd_p - tx_ring->qcp_rd_p;
> > -	else
> > -		todo = qcp_rd_p + tx_ring->cnt - tx_ring->qcp_rd_p;
> > +	todo = D_IDX(tx_ring, qcp_rd_p + tx_ring->cnt - tx_ring->qcp_rd_p);  
> 
> I'm not sure you need to add tx_ring->cnt here.
> I bet D_IDX() masks it away.

True, feel free to send a fix, or I will queue up a correction after
other work I have pending.

> >  	while (todo--) {
> >  		idx = D_IDX(tx_ring, tx_ring->rd_p++);  
> 
> That '++' looks suspicious.
> I think you need to decide whether you are incrementing pointers into the ring
> or indexes into it.
> Sometimes it is safer to use a non-wrapping index and mask when accessing the entry.
> 	entry_ptr = &ring[idx & (RING_SIZE - 1)]
> Ring full is then (read_idx == write_idx + RING_SIZE),
> ring empty (read_idx == write_idx).
> So the index just wrap at (probably)_2^32.

I may be missing the point.  I use a mix of the two, actually, the
software pointers are free running (non-wrapping) but the HW QCP
pointers wrap.  Because HW pointers wrap I always keep one entry on 
the rings empty, see nfp_net_tx_full().

RE: [PATCH net-next 9/9] nfp: eliminate an if statement in calculation of completed frames

[David Laight]

From: Jakub Kicinski
> Sent: 17 May 2017 18:37
..
> > >  	while (todo--) {
> > >  		idx = D_IDX(tx_ring, tx_ring->rd_p++);
> >
> > That '++' looks suspicious.
> > I think you need to decide whether you are incrementing pointers into the ring
> > or indexes into it.
> > Sometimes it is safer to use a non-wrapping index and mask when accessing the entry.
> > 	entry_ptr = &ring[idx & (RING_SIZE - 1)]
> > Ring full is then (read_idx == write_idx + RING_SIZE),
> > ring empty (read_idx == write_idx).
> > So the index just wrap at (probably)_2^32.
> 
> I may be missing the point.  I use a mix of the two, actually, the
> software pointers are free running (non-wrapping) but the HW QCP
> pointers wrap.  Because HW pointers wrap I always keep one entry on
> the rings empty, see nfp_net_tx_full().

Ah, I'd assumed that rd_p was a pointer, not an index.

	David