cpumask: convert drivers/net/sfc

Impact: reduce stack usage, use new cpumask API.

Remove a cpumask from the stack.  Ben Hutchings indicated that printing
a warning and returning 1 was acceptable for the corner case where allocation
fails.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Mike Travis <travis@sgi.com>
Cc: Ben Hutchings <bhutchings@solarflare.com>
Cc: linux-net-drivers@solarflare.com

1 files changed, 11 insertions, 4 deletions

diff --git a/drivers/net/sfc/efx.c b/drivers/net/sfc/efx.c
index f2e56ceee0ea..101c00a7bb73 100644
--- a/drivers/net/sfc/efx.c
+++ b/drivers/net/sfc/efx.c
@@ -854,20 +854,27 @@ static void efx_fini_io(struct efx_nic *efx)
  * interrupts across them. */
 static int efx_wanted_rx_queues(void)
 {
-        cpumask_t core_mask;
+        cpumask_var_t core_mask;
         int count;
         int cpu;
 
-        cpus_clear(core_mask);
+        if (!alloc_cpumask_var(&core_mask, GFP_KERNEL)) {
+                printk(KERN_WARNING
+                       "efx.c: allocation failure, irq balancing hobbled\n");
+                return 1;
+        }
+
+        cpumask_clear(core_mask);
         count = 0;
         for_each_online_cpu(cpu) {
-                if (!cpu_isset(cpu, core_mask)) {
+                if (!cpumask_test_cpu(cpu, core_mask)) {
                         ++count;
-                        cpumask_or(&core_mask, &core_mask,
+                        cpumask_or(core_mask, core_mask,
                                    topology_core_cpumask(cpu));
                 }
         }
 
+        free_cpumask_var(core_mask);
         return count;
 }