From: Jan Klemkow <jan@openbsd.org>
Subject: ice(4): SoftLRO
To: tech@openbsd.org
Date: Thu, 26 Jun 2025 23:33:16 +0200

Hi,

This diff add SoftLRO support to ice(4) like its done in ixl(4).  It
doesn't use the ice_decode_rx_desc_ptype() function, because we just
want two specific cases of TCP inner protocols for our SoftLRO
mechanism.

ok?

bye,
Jan

Index: dev/pci/if_ice.c
===================================================================
RCS file: /cvs/src/sys/dev/pci/if_ice.c,v
diff -u -p -r1.51 if_ice.c
--- dev/pci/if_ice.c	23 Jun 2025 08:03:22 -0000	1.51
+++ dev/pci/if_ice.c	26 Jun 2025 20:43:15 -0000
@@ -29152,6 +29152,7 @@ ice_rxeof(struct ice_softc *sc, struct i
 	struct ice_rx_map *rxm;
 	bus_dmamap_t map;
 	unsigned int cons, prod;
+	struct mbuf_list mltcp = MBUF_LIST_INITIALIZER();
 	struct mbuf_list ml = MBUF_LIST_INITIALIZER();
 	struct mbuf *m;
 	uint16_t status0, ptype;
@@ -29235,7 +29236,14 @@ ice_rxeof(struct ice_softc *sc, struct i
 				ICE_RX_FLEX_DESC_PTYPE_M;
 			ice_rx_checksum(m, status0, ptype);
 
-			ml_enqueue(&ml, m);
+#ifndef SMALL_KERNEL
+			if (ISSET(ifp->if_xflags, IFXF_LRO) &&
+			    (ptype == ICE_RX_FLEX_DECS_PTYPE_MAC_IPV4_TCP ||
+			     ptype == ICE_RX_FLEX_DECS_PTYPE_MAC_IPV6_TCP))
+				tcp_softlro_glue(&mltcp, m, ifp);
+			else
+#endif
+				ml_enqueue(&ml, m);
 
 			rxq->rxq_m_head = NULL;
 			rxq->rxq_m_tail = &rxq->rxq_m_head;
@@ -29248,8 +29256,15 @@ ice_rxeof(struct ice_softc *sc, struct i
 	} while (cons != prod);
 
 	if (done) {
+		int livelocked = 0;
+
 		rxq->rxq_cons = cons;
+		if (ifiq_input(ifiq, &mltcp))
+			livelocked = 1;
 		if (ifiq_input(ifiq, &ml))
+			livelocked = 1;
+
+		if (livelocked)
 			if_rxr_livelocked(&rxq->rxq_acct);
 		ice_rxfill(sc, rxq);
 	}
@@ -30419,6 +30434,11 @@ ice_attach_hook(struct device *self)
 	    IFCAP_CSUM_TCPv4 | IFCAP_CSUM_UDPv4 |
 	    IFCAP_CSUM_TCPv6 | IFCAP_CSUM_UDPv6 |
 	    IFCAP_TSOv4 | IFCAP_TSOv6;
+	ifp->if_capabilities |= IFCAP_LRO;
+#if notyet
+	/* for now tcplro at ice(4) is default off */
+	ifp->if_xflags |= IFXF_LRO;
+#endif
 
 	if_attach(ifp);
 	ether_ifattach(ifp);
Index: dev/pci/if_icereg.h
===================================================================
RCS file: /cvs/src/sys/dev/pci/if_icereg.h,v
diff -u -p -r1.2 if_icereg.h
--- dev/pci/if_icereg.h	25 Nov 2024 12:50:47 -0000	1.2
+++ dev/pci/if_icereg.h	26 Jun 2025 20:34:50 -0000
@@ -13676,6 +13676,8 @@ enum ice_umbcast_dest_addr_types {
 
 /* for ice_32byte_rx_flex_desc.ptype_flexi_flags0 member */
 #define ICE_RX_FLEX_DESC_PTYPE_M	(0x3FF) /* 10-bits */
+#define ICE_RX_FLEX_DECS_PTYPE_MAC_IPV4_TCP 26
+#define ICE_RX_FLEX_DECS_PTYPE_MAC_IPV6_TCP 92
 
 enum ice_rx_flex_desc_flexi_flags0_bits { /* field is 6 bits long */
 	ICE_RX_FLEX_DESC_FLEXI_FLAGS0_S = 10,