@@ -181,8 +181,6 @@ static inline int __ptep_test_and_clear_young(struct mm_struct *mm,
{
unsigned long old;
- if (!pte_young(*ptep))
- return 0;
old = pte_update(mm, addr, ptep, _PAGE_ACCESSED, 0, 0);
return (old & _PAGE_ACCESSED) != 0;
}
@@ -198,10 +196,6 @@ static inline int __ptep_test_and_clear_young(struct mm_struct *mm,
static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr,
pte_t *ptep)
{
-
- if ((pte_val(*ptep) & _PAGE_RW) == 0)
- return;
-
pte_update(mm, addr, ptep, _PAGE_RW, 0, 0);
}
@@ -209,9 +203,6 @@ static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr,
static inline void huge_ptep_set_wrprotect(struct mm_struct *mm,
unsigned long addr, pte_t *ptep)
{
- if ((pte_val(*ptep) & _PAGE_RW) == 0)
- return;
-
pte_update(mm, addr, ptep, _PAGE_RW, 0, 1);
}
@@ -47,6 +47,9 @@ static inline pte_basic_t pte_update(struct mm_struct *mm, unsigned long addr, p
pte_basic_t old = pte_val(*p);
pte_basic_t new = (old & ~(pte_basic_t)clr) | set;
+ if (new == old)
+ return old;
+
*p = __pte(new);
if (IS_ENABLED(CONFIG_44x) && (old & _PAGE_USER) && (old & _PAGE_EXEC))
On nohash/64, a few callers of pte_update() check if there is really a change in order to avoid an unnecessary write. Refactor that inside pte_update(). Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> --- arch/powerpc/include/asm/nohash/64/pgtable.h | 9 --------- arch/powerpc/include/asm/nohash/pgtable.h | 3 +++ 2 files changed, 3 insertions(+), 9 deletions(-)