ice: report hash type such as L2/L3/L4

The hardware is reporting the type of the hash used for RSS
as a PTYPE field in the receive descriptor. Use this value to set
the skb packet hash type by extending the hash type table to
cover all 10-bits of possible values (requiring some variables
to be changed from u8 to u16), and then use that table to convert
to one of the possible values in enum pkt_hash_types.

While we're here, remove the unused ptype struct value, which
makes table init easier for the zero entries, and use ranged
initializer to remove a bunch of code (works with gcc and clang).

Without this change, the kernel will recalculate the hash in software,
which can consume extra CPU cycles.

Co-developed-by: Kiran Patil <kiran.patil@intel.com>
Signed-off-by: Kiran Patil <kiran.patil@intel.com>
Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Tested-by: Tony Brelinski <tonyx.brelinski@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>

1 files changed, 18 insertions, 5 deletions

diff --git a/drivers/net/ethernet/intel/ice/ice_txrx_lib.c b/drivers/net/ethernet/intel/ice/ice_txrx_lib.c
index 166cf25d1139..171397dcf00a 100644
--- a/drivers/net/ethernet/intel/ice/ice_txrx_lib.c
+++ b/drivers/net/ethernet/intel/ice/ice_txrx_lib.c
@@ -38,10 +38,23 @@ void ice_release_rx_desc(struct ice_ring *rx_ring, u16 val)
  * ice_ptype_to_htype - get a hash type
  * @ptype: the ptype value from the descriptor
  *
- * Returns a hash type to be used by skb_set_hash
+ * Returns appropriate hash type (such as PKT_HASH_TYPE_L2/L3/L4) to be used by
+ * skb_set_hash based on PTYPE as parsed by HW Rx pipeline and is part of
+ * Rx desc.
  */
-static enum pkt_hash_types ice_ptype_to_htype(u8 __always_unused ptype)
+static enum pkt_hash_types ice_ptype_to_htype(u16 ptype)
 {
+	struct ice_rx_ptype_decoded decoded = ice_decode_rx_desc_ptype(ptype);
+
+	if (!decoded.known)
+		return PKT_HASH_TYPE_NONE;
+	if (decoded.payload_layer == ICE_RX_PTYPE_PAYLOAD_LAYER_PAY4)
+		return PKT_HASH_TYPE_L4;
+	if (decoded.payload_layer == ICE_RX_PTYPE_PAYLOAD_LAYER_PAY3)
+		return PKT_HASH_TYPE_L3;
+	if (decoded.outer_ip == ICE_RX_PTYPE_OUTER_L2)
+		return PKT_HASH_TYPE_L2;
+
 	return PKT_HASH_TYPE_NONE;
 }
 
@@ -54,7 +67,7 @@ static enum pkt_hash_types ice_ptype_to_htype(u8 __always_unused ptype)
  */
 static void
 ice_rx_hash(struct ice_ring *rx_ring, union ice_32b_rx_flex_desc *rx_desc,
-	    struct sk_buff *skb, u8 rx_ptype)
+	    struct sk_buff *skb, u16 rx_ptype)
 {
 	struct ice_32b_rx_flex_desc_nic *nic_mdid;
 	u32 hash;
@@ -81,7 +94,7 @@ ice_rx_hash(struct ice_ring *rx_ring, union ice_32b_rx_flex_desc *rx_desc,
  */
 static void
 ice_rx_csum(struct ice_ring *ring, struct sk_buff *skb,
-	    union ice_32b_rx_flex_desc *rx_desc, u8 ptype)
+	    union ice_32b_rx_flex_desc *rx_desc, u16 ptype)
 {
 	struct ice_rx_ptype_decoded decoded;
 	u16 rx_status0, rx_status1;
@@ -167,7 +180,7 @@ checksum_fail:
 void
 ice_process_skb_fields(struct ice_ring *rx_ring,
 		       union ice_32b_rx_flex_desc *rx_desc,
-		       struct sk_buff *skb, u8 ptype)
+		       struct sk_buff *skb, u16 ptype)
 {
 	ice_rx_hash(rx_ring, rx_desc, skb, ptype);