[PATCH] enic: fix build warning without CONFIG_CPUMASK_OFFSTACK

[Arnd Bergmann]

The enic driver relies on the CONFIG_CPUMASK_OFFSTACK feature to
dynamically allocate a struct member, but this is normally intended for
local variables.

Building with clang, I get a warning for a few locations that check the
address of the cpumask_var_t:

drivers/net/ethernet/cisco/enic/enic_main.c:122:22: error: address of array 'enic->msix[i].affinity_mask' will always evaluate to 'true' [-Werror,-Wpointer-bool-conversion]

As far as I can tell, the code is still correct, as the truth value of
the pointer is what we need in this configuration.  To get rid of the
warning, I split out the check into a separate function, and hide that
portion if CONFIG_CPUMASK_OFFSTACK is disabled.

Fixes: 322cf7e3a4e8 ("enic: assign affinity hint to interrupts")
Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
---
 drivers/net/ethernet/cisco/enic/enic_main.c | 18 ++++++++++++------
 1 file changed, 12 insertions(+), 6 deletions(-)

diff --git a/drivers/net/ethernet/cisco/enic/enic_main.c b/drivers/net/ethernet/cisco/enic/enic_main.c
index 9a7f70db20c7..f652a8bd163e 100644
--- a/drivers/net/ethernet/cisco/enic/enic_main.c
+++ b/drivers/net/ethernet/cisco/enic/enic_main.c
@@ -112,6 +112,15 @@ static struct enic_intr_mod_range mod_range[ENIC_MAX_LINK_SPEEDS] = {
 	{3,  6}, /* 10 - 40 Gbps */
 };
 
+static inline int enic_affinity_mask_empty(struct enic *enic, int i)
+{
+#ifdef CONFIG_CPUMASK_OFFSTACK
+	if (!enic->msix[i].affinity_mask)
+		return 1;
+#endif
+	return cpumask_empty(enic->msix[i].affinity_mask);
+}
+
 static void enic_init_affinity_hint(struct enic *enic)
 {
 	int numa_node = dev_to_node(&enic->pdev->dev);
@@ -119,8 +128,7 @@ static void enic_init_affinity_hint(struct enic *enic)
 
 	for (i = 0; i < enic->intr_count; i++) {
 		if (enic_is_err_intr(enic, i) || enic_is_notify_intr(enic, i) ||
-		    (enic->msix[i].affinity_mask &&
-		     !cpumask_empty(enic->msix[i].affinity_mask)))
+		    !enic_affinity_mask_empty(enic, i))
 			continue;
 		if (zalloc_cpumask_var(&enic->msix[i].affinity_mask,
 				       GFP_KERNEL))
@@ -148,8 +156,7 @@ static void enic_set_affinity_hint(struct enic *enic)
 	for (i = 0; i < enic->intr_count; i++) {
 		if (enic_is_err_intr(enic, i)		||
 		    enic_is_notify_intr(enic, i)	||
-		    !enic->msix[i].affinity_mask	||
-		    cpumask_empty(enic->msix[i].affinity_mask))
+		    enic_affinity_mask_empty(enic, i))
 			continue;
 		err = irq_set_affinity_hint(enic->msix_entry[i].vector,
 					    enic->msix[i].affinity_mask);
@@ -161,8 +168,7 @@ static void enic_set_affinity_hint(struct enic *enic)
 	for (i = 0; i < enic->wq_count; i++) {
 		int wq_intr = enic_msix_wq_intr(enic, i);
 
-		if (enic->msix[wq_intr].affinity_mask &&
-		    !cpumask_empty(enic->msix[wq_intr].affinity_mask))
+		if (!enic_affinity_mask_empty(enic, wq_intr))
 			netif_set_xps_queue(enic->netdev,
 					    enic->msix[wq_intr].affinity_mask,
 					    i);
-- 
2.20.0