enic: Move enic resource adjustments to separate function

Move the enic resource adjustments out of enic_set_intr_mode() and into
its own function, enic_adjust_resources().

Co-developed-by: John Daley <johndale@cisco.com>
Signed-off-by: John Daley <johndale@cisco.com>
Co-developed-by: Satish Kharat <satishkh@cisco.com>
Signed-off-by: Satish Kharat <satishkh@cisco.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Nelson Escobar <neescoba@cisco.com>
Reviewed-by: Vadim Fedorenko <vadim.fedorenko@linux.dev>
Link: https://patch.msgid.link/20241113-remove_vic_resource_limits-v4-6-a34cf8570c67@cisco.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/drivers/net/ethernet/cisco/enic/enic_main.c b/drivers/net/ethernet/cisco/enic/enic_main.c
index 8b07899462d0671843579d16c8c935d9ebbe447b..84e85c9e2bf52f0089c0a8d03fb6d22ada4d086c 100644 (file)
--- a/drivers/net/ethernet/cisco/enic/enic_main.c
+++ b/drivers/net/ethernet/cisco/enic/enic_main.c
@@ -2448,30 +2448,11 @@ static int enic_set_intr_mode(struct enic *enic)
        /* Set interrupt mode (INTx, MSI, MSI-X) depending
         * on system capabilities.
         *
-        * We need a minimum of 1 RQ, 1 WQ, and 2 CQs
-        *
+        * Try MSI-X first
         */
 
-       if (enic->rq_avail < 1 || enic->wq_avail < 1 || enic->cq_avail < 2) {
-               dev_err(enic_get_dev(enic),
-                       "Not enough resources available rq: %d wq: %d cq: %d\n",
-                       enic->rq_avail, enic->wq_avail,
-                       enic->cq_avail);
-               return -ENOSPC;
-       }
-
-       /* if RSS isn't set, then we can only use one RQ */
-       if (!ENIC_SETTING(enic, RSS))
-               enic->rq_avail = 1;
-
-       /* Try MSI-X first */
        if (enic->config.intr_mode < 1 &&
            enic->intr_avail >= ENIC_MSIX_MIN_INTR) {
-               unsigned int max_queues;
-               unsigned int rq_default;
-               unsigned int rq_avail;
-               unsigned int wq_avail;
-
                for (i = 0; i < enic->intr_avail; i++)
                        enic->msix_entry[i].entry = i;
 
@@ -2479,28 +2460,6 @@ static int enic_set_intr_mode(struct enic *enic)
                                                 ENIC_MSIX_MIN_INTR,
                                                 enic->intr_avail);
                if (num_intr > 0) {
-                       wq_avail = min(enic->wq_avail, ENIC_WQ_MAX);
-                       rq_default = netif_get_num_default_rss_queues();
-                       rq_avail = min3(enic->rq_avail, ENIC_RQ_MAX, rq_default);
-                       max_queues = min(enic->cq_avail,
-                                        enic->intr_avail - ENIC_MSIX_RESERVED_INTR);
-
-                       if (wq_avail + rq_avail <= max_queues) {
-                               enic->rq_count = rq_avail;
-                               enic->wq_count = wq_avail;
-                       } else {
-                               /* recalculate wq/rq count */
-                               if (rq_avail < wq_avail) {
-                                       enic->rq_count = min(rq_avail, max_queues / 2);
-                                       enic->wq_count = max_queues - enic->rq_count;
-                               } else {
-                                       enic->wq_count = min(wq_avail, max_queues / 2);
-                                       enic->rq_count = max_queues - enic->wq_count;
-                               }
-                       }
-                       enic->cq_count = enic->rq_count + enic->wq_count;
-                       enic->intr_count = enic->cq_count + ENIC_MSIX_RESERVED_INTR;
-
                        vnic_dev_set_intr_mode(enic->vdev,
                                               VNIC_DEV_INTR_MODE_MSIX);
                        enic->intr_avail = num_intr;
@@ -2516,14 +2475,8 @@ static int enic_set_intr_mode(struct enic *enic)
        if (enic->config.intr_mode < 2 &&
            enic->intr_avail >= 1 &&
            !pci_enable_msi(enic->pdev)) {
-
-               enic->rq_count = 1;
-               enic->wq_count = 1;
-               enic->cq_count = 2;
-               enic->intr_count = 1;
                enic->intr_avail = 1;
                vnic_dev_set_intr_mode(enic->vdev, VNIC_DEV_INTR_MODE_MSI);
-
                return 0;
        }
 
@@ -2537,14 +2490,8 @@ static int enic_set_intr_mode(struct enic *enic)
 
        if (enic->config.intr_mode < 3 &&
            enic->intr_avail >= 3) {
-
-               enic->rq_count = 1;
-               enic->wq_count = 1;
-               enic->cq_count = 2;
-               enic->intr_count = 3;
                enic->intr_avail = 3;
                vnic_dev_set_intr_mode(enic->vdev, VNIC_DEV_INTR_MODE_INTX);
-
                return 0;
        }
 
@@ -2569,6 +2516,67 @@ static void enic_clear_intr_mode(struct enic *enic)
        vnic_dev_set_intr_mode(enic->vdev, VNIC_DEV_INTR_MODE_UNKNOWN);
 }
 
+static int enic_adjust_resources(struct enic *enic)
+{
+       unsigned int max_queues;
+       unsigned int rq_default;
+       unsigned int rq_avail;
+       unsigned int wq_avail;
+
+       if (enic->rq_avail < 1 || enic->wq_avail < 1 || enic->cq_avail < 2) {
+               dev_err(enic_get_dev(enic),
+                       "Not enough resources available rq: %d wq: %d cq: %d\n",
+                       enic->rq_avail, enic->wq_avail,
+                       enic->cq_avail);
+               return -ENOSPC;
+       }
+
+       /* if RSS isn't set, then we can only use one RQ */
+       if (!ENIC_SETTING(enic, RSS))
+               enic->rq_avail = 1;
+
+       switch (vnic_dev_get_intr_mode(enic->vdev)) {
+       case VNIC_DEV_INTR_MODE_INTX:
+       case VNIC_DEV_INTR_MODE_MSI:
+               enic->rq_count = 1;
+               enic->wq_count = 1;
+               enic->cq_count = 2;
+               enic->intr_count = enic->intr_avail;
+               break;
+       case VNIC_DEV_INTR_MODE_MSIX:
+               /* Adjust the number of wqs/rqs/cqs/interrupts that will be
+                * used based on which resource is the most constrained
+                */
+               wq_avail = min(enic->wq_avail, ENIC_WQ_MAX);
+               rq_default = netif_get_num_default_rss_queues();
+               rq_avail = min3(enic->rq_avail, ENIC_RQ_MAX, rq_default);
+               max_queues = min(enic->cq_avail,
+                                enic->intr_avail - ENIC_MSIX_RESERVED_INTR);
+               if (wq_avail + rq_avail <= max_queues) {
+                       enic->rq_count = rq_avail;
+                       enic->wq_count = wq_avail;
+               } else {
+                       /* recalculate wq/rq count */
+                       if (rq_avail < wq_avail) {
+                               enic->rq_count = min(rq_avail, max_queues / 2);
+                               enic->wq_count = max_queues - enic->rq_count;
+                       } else {
+                               enic->wq_count = min(wq_avail, max_queues / 2);
+                               enic->rq_count = max_queues - enic->wq_count;
+                       }
+               }
+               enic->cq_count = enic->rq_count + enic->wq_count;
+               enic->intr_count = enic->cq_count + ENIC_MSIX_RESERVED_INTR;
+
+               break;
+       default:
+               dev_err(enic_get_dev(enic), "Unknown interrupt mode\n");
+               return -EINVAL;
+       }
+
+       return 0;
+}
+
 static void enic_get_queue_stats_rx(struct net_device *dev, int idx,
                                    struct netdev_queue_stats_rx *rxs)
 {
@@ -2807,9 +2815,7 @@ static int enic_dev_init(struct enic *enic)
         */
        enic_kdump_kernel_config(enic);
 
-       /* Set interrupt mode based on resource counts and system
-        * capabilities
-        */
+       /* Set interrupt mode based on system capabilities */
 
        err = enic_set_intr_mode(enic);
        if (err) {
@@ -2818,6 +2824,13 @@ static int enic_dev_init(struct enic *enic)
                goto err_out_free_vnic_resources;
        }
 
+       /* Adjust resource counts based on most constrained resources */
+       err = enic_adjust_resources(enic);
+       if (err) {
+               dev_err(dev, "Failed to adjust resources\n");
+               goto err_out_free_vnic_resources;
+       }
+
        /* Allocate and configure vNIC resources
         */