Introduce support for a lowest priority wildcard (catch-all) rule in
ethtool's Network Flow Classification (NFC) for the igc driver. The
wildcard rule directs all unmatched network traffic, including traffic not
captured by Receive Side Scaling (RSS), to a specified queue. This
functionality utilizes the Default Queue feature available in I225/I226
hardware.
The implementation has been validated on Intel ADL-S systems with two
back-to-back connected I226 network interfaces.
Testing Procedure:
1. On the Device Under Test (DUT), verify the initial statistic:
$ ethtool -S enp1s0 | grep rx_q.*packets
rx_queue_0_packets: 0
rx_queue_1_packets: 0
rx_queue_2_packets: 0
rx_queue_3_packets: 0
2. From the Link Partner, send 10 ARP packets:
$ arping -c 10 -I enp170s0 169.254.1.2
3. On the DUT, verify the packet reception on Queue 0:
$ ethtool -S enp1s0 | grep rx_q.*packets
rx_queue_0_packets: 10
rx_queue_1_packets: 0
rx_queue_2_packets: 0
rx_queue_3_packets: 0
4. On the DUT, add a wildcard rule to route all packets to Queue 3:
$ sudo ethtool -N enp1s0 flow-type ether queue 3
5. From the Link Partner, send another 10 ARP packets:
$ arping -c 10 -I enp170s0 169.254.1.2
6. Now, packets are routed to Queue 3 by the wildcard (Default Queue) rule:
$ ethtool -S enp1s0 | grep rx_q.*packets
rx_queue_0_packets: 10
rx_queue_1_packets: 0
rx_queue_2_packets: 0
rx_queue_3_packets: 10
7. On the DUT, add a EtherType rule to route ARP packet to Queue 1:
$ sudo ethtool -N enp1s0 flow-type ether proto 0x0806 queue 1
8. From the Link Partner, send another 10 ARP packets:
$ arping -c 10 -I enp170s0 169.254.1.2
9. Now, packets are routed to Queue 1 by the EtherType rule because it is
higher priority than the wildcard (Default Queue) rule:
$ ethtool -S enp1s0 | grep rx_q.*packets
rx_queue_0_packets: 10
rx_queue_1_packets: 10
rx_queue_2_packets: 0
rx_queue_3_packets: 10
10. On the DUT, delete all the NFC rules:
$ sudo ethtool -N enp1s0 delete 63
$ sudo ethtool -N enp1s0 delete 64
11. From the Link Partner, send another 10 ARP packets:
$ arping -c 10 -I enp170s0 169.254.1.2
12. Now, packets are routed to Queue 0 because the value of Default Queue
is reset back to 0:
$ ethtool -S enp1s0 | grep rx_q.*packets
rx_queue_0_packets: 20
rx_queue_1_packets: 10
rx_queue_2_packets: 0
rx_queue_3_packets: 10
Reviewed-by: Kurt Kanzenbach <kurt@linutronix.de>
Co-developed-by: Blanco Alcaine Hector <hector.blanco.alcaine@intel.com>
Signed-off-by: Blanco Alcaine Hector <hector.blanco.alcaine@intel.com>
Signed-off-by: Song Yoong Siang <yoong.siang.song@intel.com>
---
drivers/net/ethernet/intel/igc/igc.h | 11 +++++++---
drivers/net/ethernet/intel/igc/igc_defines.h | 1 +
drivers/net/ethernet/intel/igc/igc_ethtool.c | 18 ++++++++++++++++
drivers/net/ethernet/intel/igc/igc_main.c | 22 ++++++++++++++++++++
4 files changed, 49 insertions(+), 3 deletions(-)
diff --git a/drivers/net/ethernet/intel/igc/igc.h b/drivers/net/ethernet/intel/igc/igc.h
index 0b35e593d5ee..c580ecc954be 100644
--- a/drivers/net/ethernet/intel/igc/igc.h
+++ b/drivers/net/ethernet/intel/igc/igc.h
@@ -631,6 +631,7 @@ enum igc_filter_match_flags {
IGC_FILTER_FLAG_DST_MAC_ADDR = BIT(3),
IGC_FILTER_FLAG_USER_DATA = BIT(4),
IGC_FILTER_FLAG_VLAN_ETYPE = BIT(5),
+ IGC_FILTER_FLAG_DEFAULT_QUEUE = BIT(6),
};
struct igc_nfc_filter {
@@ -658,10 +659,14 @@ struct igc_nfc_rule {
bool flex;
};
-/* IGC supports a total of 32 NFC rules: 16 MAC address based, 8 VLAN priority
- * based, 8 ethertype based and 32 Flex filter based rules.
+/* IGC supports a total of 65 NFC rules, listed below in order of priority:
+ * - 16 MAC address based filtering rules (highest priority)
+ * - 8 ethertype based filtering rules
+ * - 32 Flex filter based filtering rules
+ * - 8 VLAN priority based filtering rules
+ * - 1 default queue rule (lowest priority)
*/
-#define IGC_MAX_RXNFC_RULES 64
+#define IGC_MAX_RXNFC_RULES 65
struct igc_flex_filter {
u8 index;
diff --git a/drivers/net/ethernet/intel/igc/igc_defines.h b/drivers/net/ethernet/intel/igc/igc_defines.h
index d80254f2a278..498ba1522ca4 100644
--- a/drivers/net/ethernet/intel/igc/igc_defines.h
+++ b/drivers/net/ethernet/intel/igc/igc_defines.h
@@ -391,6 +391,7 @@
#define IGC_MRQC_RSS_FIELD_IPV6_TCP 0x00200000
#define IGC_MRQC_RSS_FIELD_IPV4_UDP 0x00400000
#define IGC_MRQC_RSS_FIELD_IPV6_UDP 0x00800000
+#define IGC_MRQC_DEFAULT_QUEUE_MASK GENMASK(5, 3)
/* Header split receive */
#define IGC_RFCTL_IPV6_EX_DIS 0x00010000
diff --git a/drivers/net/ethernet/intel/igc/igc_ethtool.c b/drivers/net/ethernet/intel/igc/igc_ethtool.c
index a7f397b58cd6..ecb35b693ce5 100644
--- a/drivers/net/ethernet/intel/igc/igc_ethtool.c
+++ b/drivers/net/ethernet/intel/igc/igc_ethtool.c
@@ -1283,6 +1283,24 @@ static void igc_ethtool_init_nfc_rule(struct igc_nfc_rule *rule,
rule->flex = true;
else
rule->flex = false;
+
+ /* The wildcard rule is only applied if:
+ * a) None of the other filtering rules match (match_flags is zero)
+ * b) The flow type is ETHER_FLOW only (no additional fields set)
+ * c) Mask for Source MAC address is not specified (all zeros)
+ * d) Mask for Destination MAC address is not specified (all zeros)
+ * e) Mask for L2 EtherType is not specified (zero)
+ *
+ * If all these conditions are met, the rule is treated as a wildcard
+ * rule. Default queue feature will be used, so that all packets that do
+ * not match any other rule will be routed to the default queue.
+ */
+ if (!rule->filter.match_flags &&
+ fsp->flow_type == ETHER_FLOW &&
+ is_zero_ether_addr(fsp->m_u.ether_spec.h_source) &&
+ is_zero_ether_addr(fsp->m_u.ether_spec.h_dest) &&
+ !fsp->m_u.ether_spec.h_proto)
+ rule->filter.match_flags = IGC_FILTER_FLAG_DEFAULT_QUEUE;
}
/**
diff --git a/drivers/net/ethernet/intel/igc/igc_main.c b/drivers/net/ethernet/intel/igc/igc_main.c
index 2e12915b42a9..87311ea47018 100644
--- a/drivers/net/ethernet/intel/igc/igc_main.c
+++ b/drivers/net/ethernet/intel/igc/igc_main.c
@@ -3874,6 +3874,22 @@ static void igc_del_flex_filter(struct igc_adapter *adapter,
wr32(IGC_WUFC, wufc);
}
+static void igc_set_default_queue_filter(struct igc_adapter *adapter, u32 queue)
+{
+ struct igc_hw *hw = &adapter->hw;
+ u32 mrqc = rd32(IGC_MRQC);
+
+ mrqc &= ~IGC_MRQC_DEFAULT_QUEUE_MASK;
+ mrqc |= FIELD_PREP(IGC_MRQC_DEFAULT_QUEUE_MASK, queue);
+ wr32(IGC_MRQC, mrqc);
+}
+
+static void igc_reset_default_queue_filter(struct igc_adapter *adapter)
+{
+ /* Reset the default queue to its default value which is Queue 0 */
+ igc_set_default_queue_filter(adapter, 0);
+}
+
static int igc_enable_nfc_rule(struct igc_adapter *adapter,
struct igc_nfc_rule *rule)
{
@@ -3912,6 +3928,9 @@ static int igc_enable_nfc_rule(struct igc_adapter *adapter,
return err;
}
+ if (rule->filter.match_flags & IGC_FILTER_FLAG_DEFAULT_QUEUE)
+ igc_set_default_queue_filter(adapter, rule->action);
+
return 0;
}
@@ -3939,6 +3958,9 @@ static void igc_disable_nfc_rule(struct igc_adapter *adapter,
if (rule->filter.match_flags & IGC_FILTER_FLAG_DST_MAC_ADDR)
igc_del_mac_filter(adapter, IGC_MAC_FILTER_TYPE_DST,
rule->filter.dst_addr);
+
+ if (rule->filter.match_flags & IGC_FILTER_FLAG_DEFAULT_QUEUE)
+ igc_reset_default_queue_filter(adapter);
}
/**
--
2.34.1On 20/06/2025 13:02, Song Yoong Siang wrote: > Introduce support for a lowest priority wildcard (catch-all) rule in > ethtool's Network Flow Classification (NFC) for the igc driver. The > wildcard rule directs all unmatched network traffic, including traffic not > captured by Receive Side Scaling (RSS), to a specified queue. This > functionality utilizes the Default Queue feature available in I225/I226 > hardware. > > The implementation has been validated on Intel ADL-S systems with two > back-to-back connected I226 network interfaces. > > Testing Procedure: > 1. On the Device Under Test (DUT), verify the initial statistic: > $ ethtool -S enp1s0 | grep rx_q.*packets > rx_queue_0_packets: 0 > rx_queue_1_packets: 0 > rx_queue_2_packets: 0 > rx_queue_3_packets: 0 > > 2. From the Link Partner, send 10 ARP packets: > $ arping -c 10 -I enp170s0 169.254.1.2 > > 3. On the DUT, verify the packet reception on Queue 0: > $ ethtool -S enp1s0 | grep rx_q.*packets > rx_queue_0_packets: 10 > rx_queue_1_packets: 0 > rx_queue_2_packets: 0 > rx_queue_3_packets: 0 > > 4. On the DUT, add a wildcard rule to route all packets to Queue 3: > $ sudo ethtool -N enp1s0 flow-type ether queue 3 > > 5. From the Link Partner, send another 10 ARP packets: > $ arping -c 10 -I enp170s0 169.254.1.2 > > 6. Now, packets are routed to Queue 3 by the wildcard (Default Queue) rule: > $ ethtool -S enp1s0 | grep rx_q.*packets > rx_queue_0_packets: 10 > rx_queue_1_packets: 0 > rx_queue_2_packets: 0 > rx_queue_3_packets: 10 > > 7. On the DUT, add a EtherType rule to route ARP packet to Queue 1: > $ sudo ethtool -N enp1s0 flow-type ether proto 0x0806 queue 1 > > 8. From the Link Partner, send another 10 ARP packets: > $ arping -c 10 -I enp170s0 169.254.1.2 > > 9. Now, packets are routed to Queue 1 by the EtherType rule because it is > higher priority than the wildcard (Default Queue) rule: > $ ethtool -S enp1s0 | grep rx_q.*packets > rx_queue_0_packets: 10 > rx_queue_1_packets: 10 > rx_queue_2_packets: 0 > rx_queue_3_packets: 10 > > 10. On the DUT, delete all the NFC rules: > $ sudo ethtool -N enp1s0 delete 63 > $ sudo ethtool -N enp1s0 delete 64 > > 11. From the Link Partner, send another 10 ARP packets: > $ arping -c 10 -I enp170s0 169.254.1.2 > > 12. Now, packets are routed to Queue 0 because the value of Default Queue > is reset back to 0: > $ ethtool -S enp1s0 | grep rx_q.*packets > rx_queue_0_packets: 20 > rx_queue_1_packets: 10 > rx_queue_2_packets: 0 > rx_queue_3_packets: 10 > > Reviewed-by: Kurt Kanzenbach <kurt@linutronix.de> > Co-developed-by: Blanco Alcaine Hector <hector.blanco.alcaine@intel.com> > Signed-off-by: Blanco Alcaine Hector <hector.blanco.alcaine@intel.com> > Signed-off-by: Song Yoong Siang <yoong.siang.song@intel.com> > --- > drivers/net/ethernet/intel/igc/igc.h | 11 +++++++--- > drivers/net/ethernet/intel/igc/igc_defines.h | 1 + > drivers/net/ethernet/intel/igc/igc_ethtool.c | 18 ++++++++++++++++ > drivers/net/ethernet/intel/igc/igc_main.c | 22 ++++++++++++++++++++ > 4 files changed, 49 insertions(+), 3 deletions(-) > Tested-by: Mor Bar-Gabay <morx.bar.gabay@intel.com>
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