powerpc/mm/radix: Don't do page walk cache flush when doing full mm flush

For fullmm tlb flush, we do a flush with RIC_FLUSH_ALL which will invalidate all
related caches (radix__tlb_flush()). Hence the pwc flush is not needed.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Acked-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

arch/powerpc/mm/tlb-radix.c

@@ -129,6 +129,12 @@ void radix__local_flush_tlb_pwc(struct mmu_gather *tlb, unsigned long addr)
 {
 	unsigned long pid;
 	struct mm_struct *mm = tlb->mm;
+	/*
+	 * If we are doing a full mm flush, we will do a tlb flush
+	 * with RIC_FLUSH_ALL later.
+	 */
+	if (tlb->fullmm)
+		return;
 
 	preempt_disable();
 
@@ -195,6 +201,12 @@ void radix__flush_tlb_pwc(struct mmu_gather *tlb, unsigned long addr)
 	unsigned long pid;
 	struct mm_struct *mm = tlb->mm;
 
+	/*
+	 * If we are doing a full mm flush, we will do a tlb flush
+	 * with RIC_FLUSH_ALL later.
+	 */
+	if (tlb->fullmm)
+		return;
 	preempt_disable();
 
 	pid = mm->context.id;