amd-xgbe: Add NUMA affinity support for IRQ hints

For IRQ affinity, set the affinity hints for the IRQs to be (initially) on
the processors corresponding to the NUMA node of the device.

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/amd/xgbe/xgbe-drv.c

@@ -192,12 +192,17 @@ static int xgbe_alloc_channels(struct xgbe_prv_data *pdata)
 	struct xgbe_channel *channel;
 	struct xgbe_ring *ring;
 	unsigned int count, i;
+	unsigned int cpu;
 	int node;
 
-	node = dev_to_node(pdata->dev);
-
 	count = max_t(unsigned int, pdata->tx_ring_count, pdata->rx_ring_count);
 	for (i = 0; i < count; i++) {
+		/* Attempt to use a CPU on the node the device is on */
+		cpu = cpumask_local_spread(i, dev_to_node(pdata->dev));
+
+		/* Set the allocation node based on the returned CPU */
+		node = cpu_to_node(cpu);
+
 		channel = xgbe_alloc_node(sizeof(*channel), node);
 		if (!channel)
 			goto err_mem;
@@ -209,6 +214,7 @@ static int xgbe_alloc_channels(struct xgbe_prv_data *pdata)
 		channel->dma_regs = pdata->xgmac_regs + DMA_CH_BASE +
 				    (DMA_CH_INC * i);
 		channel->node = node;
+		cpumask_set_cpu(cpu, &channel->affinity_mask);
 
 		if (pdata->per_channel_irq)
 			channel->dma_irq = pdata->channel_irq[i];
@@ -236,7 +242,7 @@ static int xgbe_alloc_channels(struct xgbe_prv_data *pdata)
 		}
 
 		netif_dbg(pdata, drv, pdata->netdev,
-			  "%s: node=%d\n", channel->name, node);
+			  "%s: cpu=%u, node=%d\n", channel->name, cpu, node);
 
 		netif_dbg(pdata, drv, pdata->netdev,
 			  "%s: dma_regs=%p, dma_irq=%d, tx=%p, rx=%p\n",
@@ -916,6 +922,9 @@ static int xgbe_request_irqs(struct xgbe_prv_data *pdata)
 				     channel->dma_irq);
 			goto err_dma_irq;
 		}
+
+		irq_set_affinity_hint(channel->dma_irq,
+				      &channel->affinity_mask);
 	}
 
 	return 0;
@@ -925,6 +934,7 @@ err_dma_irq:
 	for (i--; i < pdata->channel_count; i--) {
 		channel = pdata->channel[i];
 
+		irq_set_affinity_hint(channel->dma_irq, NULL);
 		devm_free_irq(pdata->dev, channel->dma_irq, channel);
 	}
 
@@ -952,6 +962,8 @@ static void xgbe_free_irqs(struct xgbe_prv_data *pdata)
 
 	for (i = 0; i < pdata->channel_count; i++) {
 		channel = pdata->channel[i];
+
+		irq_set_affinity_hint(channel->dma_irq, NULL);
 		devm_free_irq(pdata->dev, channel->dma_irq, channel);
 	}
 }

drivers/net/ethernet/amd/xgbe/xgbe.h

@@ -128,6 +128,7 @@
 #include <linux/net_tstamp.h>
 #include <net/dcbnl.h>
 #include <linux/completion.h>
+#include <linux/cpumask.h>
 
 #define XGBE_DRV_NAME		"amd-xgbe"
 #define XGBE_DRV_VERSION	"1.0.3"
@@ -465,6 +466,7 @@ struct xgbe_channel {
 	struct xgbe_ring *rx_ring;
 
 	int node;
+	cpumask_t affinity_mask;
 } ____cacheline_aligned;
 
 enum xgbe_state {