x86, 32-bit: improve lazy TLB handling code

Impact: micro-optimize the 32-bit TLB flush code

Use the faster x86_{read,write}_percpu() accessors here.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/arch/x86/kernel/tlb_32.c b/arch/x86/kernel/tlb_32.c
index f4049f3..4290d91 100644
--- a/arch/x86/kernel/tlb_32.c
+++ b/arch/x86/kernel/tlb_32.c
@@ -34,9 +34,8 @@
  */
 void leave_mm(int cpu)
 {
-	if (per_cpu(cpu_tlbstate, cpu).state == TLBSTATE_OK)
-		BUG();
-	cpu_clear(cpu, per_cpu(cpu_tlbstate, cpu).active_mm->cpu_vm_mask);
+	BUG_ON(x86_read_percpu(cpu_tlbstate.state) == TLBSTATE_OK);
+	cpu_clear(cpu, x86_read_percpu(cpu_tlbstate.active_mm)->cpu_vm_mask);
 	load_cr3(swapper_pg_dir);
 }
 EXPORT_SYMBOL_GPL(leave_mm);
@@ -104,8 +103,8 @@
 		 * BUG();
 		 */
 
-	if (flush_mm == per_cpu(cpu_tlbstate, cpu).active_mm) {
-		if (per_cpu(cpu_tlbstate, cpu).state == TLBSTATE_OK) {
+	if (flush_mm == x86_read_percpu(cpu_tlbstate.active_mm)) {
+		if (x86_read_percpu(cpu_tlbstate.state) == TLBSTATE_OK) {
 			if (flush_va == TLB_FLUSH_ALL)
 				local_flush_tlb();
 			else
@@ -238,7 +237,7 @@
 	unsigned long cpu = smp_processor_id();
 
 	__flush_tlb_all();
-	if (per_cpu(cpu_tlbstate, cpu).state == TLBSTATE_LAZY)
+	if (x86_read_percpu(cpu_tlbstate.state) == TLBSTATE_LAZY)
 		leave_mm(cpu);
 }