[PATCH] i386: avoid checking for cpu gone when CONFIG_HOTPLUG_CPU not defined

Avoid checking for cpu gone in mm hot path when CONFIG_HOTPLUG_CPU is not
defined.

Signed-off-by: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Cc: Andi Kleen <ak@suse.de>
Cc: Gautham R Shenoy <ego@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

1 files changed, 3 insertions, 1 deletions

diff --git a/arch/i386/kernel/smp.c b/arch/i386/kernel/smp.c
index f8667109db1c..f98c3ffd6fc3 100644
--- a/arch/i386/kernel/smp.c
+++ b/arch/i386/kernel/smp.c
@@ -359,10 +359,12 @@ void native_flush_tlb_others(const cpumask_t *cpumaskp, struct mm_struct *mm,
         BUG_ON(cpu_isset(smp_processor_id(), cpumask));
         BUG_ON(!mm);
 
+#ifdef CONFIG_HOTPLUG_CPU
         /* If a CPU which we ran on has gone down, OK. */
         cpus_and(cpumask, cpumask, cpu_online_map);
-        if (cpus_empty(cpumask))
+        if (unlikely(cpus_empty(cpumask)))
                 return;
+#endif
 
         /*
          * i'm not happy about this global shared spinlock in the