s390/pgtable: skip pgste updates on full flush

On process exit there is no more need for the pgste information.
Skip the expensive storage key operations which should speed up
termination of KVM processes.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

arch/s390/include/asm/pgtable.h

@@ -1144,10 +1144,9 @@ static inline pte_t ptep_get_and_clear_full(struct mm_struct *mm,
 	pgste_t pgste;
 	pte_t pte;
 
-	if (mm_has_pgste(mm)) {
+	if (!full && mm_has_pgste(mm)) {
 		pgste = pgste_get_lock(ptep);
-		if (!full)
-			pgste = pgste_ipte_notify(mm, address, ptep, pgste);
+		pgste = pgste_ipte_notify(mm, address, ptep, pgste);
 	}
 
 	pte = *ptep;
@@ -1155,7 +1154,7 @@ static inline pte_t ptep_get_and_clear_full(struct mm_struct *mm,
 		__ptep_ipte(address, ptep);
 	pte_val(*ptep) = _PAGE_INVALID;
 
-	if (mm_has_pgste(mm)) {
+	if (!full && mm_has_pgste(mm)) {
 		pgste = pgste_update_all(&pte, pgste);
 		pgste_set_unlock(ptep, pgste);
 	}