[PATCH net-next 03/11] bnxt_en: assign CPU affinity hints to bnxt_en IRQs

[Michael Chan]

From: Vasundhara Volam <vasundhara-v.vo...@broadcom.com>

This patch provides hints to irqbalance to map bnxt_en device IRQs
to specific CPU cores. cpumask_local_spread() is used, which first
maps IRQs to near NUMA cores; when those cores are exhausted, IRQs
are mapped to far NUMA cores.

Signed-off-by: Vasundhara Volam <vasundhara-v.vo...@broadcom.com>
Signed-off-by: Michael Chan <michael.c...@broadcom.com>
---
 drivers/net/ethernet/broadcom/bnxt/bnxt.c | 25 ++++++++++++++++++++++++-
 drivers/net/ethernet/broadcom/bnxt/bnxt.h |  4 +++-
 2 files changed, 27 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c 
b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
index 4b0a807..9657bfb 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
@@ -49,6 +49,7 @@
 #include <linux/aer.h>
 #include <linux/bitmap.h>
 #include <linux/cpu_rmap.h>
+#include <linux/cpumask.h>
 
 #include "bnxt_hsi.h"
 #include "bnxt.h"
@@ -5554,8 +5555,15 @@ static void bnxt_free_irq(struct bnxt *bp)
 
        for (i = 0; i < bp->cp_nr_rings; i++) {
                irq = &bp->irq_tbl[i];
-               if (irq->requested)
+               if (irq->requested) {
+                       if (irq->have_cpumask) {
+                               irq_set_affinity_hint(irq->vector, NULL);
+                               free_cpumask_var(irq->cpu_mask);
+                               irq->have_cpumask = 0;
+                       }
                        free_irq(irq->vector, bp->bnapi[i]);
+               }
+
                irq->requested = 0;
        }
 }
@@ -5588,6 +5596,21 @@ static int bnxt_request_irq(struct bnxt *bp)
                        break;
 
                irq->requested = 1;
+
+               if (zalloc_cpumask_var(&irq->cpu_mask, GFP_KERNEL)) {
+                       int numa_node = dev_to_node(&bp->pdev->dev);
+
+                       irq->have_cpumask = 1;
+                       cpumask_set_cpu(cpumask_local_spread(i, numa_node),
+                                       irq->cpu_mask);
+                       rc = irq_set_affinity_hint(irq->vector, irq->cpu_mask);
+                       if (rc) {
+                               netdev_warn(bp->dev,
+                                           "Set affinity failed, IRQ = %d\n",
+                                           irq->vector);
+                               break;
+                       }
+               }
        }
        return rc;
 }
diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.h 
b/drivers/net/ethernet/broadcom/bnxt/bnxt.h
index 568516f..801c0f7 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.h
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.h
@@ -701,8 +701,10 @@ struct bnxt_napi {
 struct bnxt_irq {
        irq_handler_t   handler;
        unsigned int    vector;
-       u8              requested;
+       u8              requested:1;
+       u8              have_cpumask:1;
        char            name[IFNAMSIZ + 2];
+       cpumask_var_t   cpu_mask;
 };
 
 #define HWRM_RING_ALLOC_TX     0x1
-- 
1.8.3.1