[PATCH 03/17] powerpc/nohash: use IS_ENABLED() to simplify __set_pte_at()

From: Christophe Leroy
Date: Fri May 04 2018 - 08:34:07 EST


By using IS_ENABLED() we can simplify __set_pte_at() by removing
redundant *ptep = pte

Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxx>
---
arch/powerpc/include/asm/nohash/pgtable.h | 23 ++++++++---------------
1 file changed, 8 insertions(+), 15 deletions(-)

diff --git a/arch/powerpc/include/asm/nohash/pgtable.h b/arch/powerpc/include/asm/nohash/pgtable.h
index f2fe3cbe90af..077472640b35 100644
--- a/arch/powerpc/include/asm/nohash/pgtable.h
+++ b/arch/powerpc/include/asm/nohash/pgtable.h
@@ -148,40 +148,33 @@ extern void set_pte_at(struct mm_struct *mm, unsigned long addr, pte_t *ptep,
static inline void __set_pte_at(struct mm_struct *mm, unsigned long addr,
pte_t *ptep, pte_t pte, int percpu)
{
-#if defined(CONFIG_PPC32) && defined(CONFIG_PTE_64BIT)
/* Second case is 32-bit with 64-bit PTE. In this case, we
* can just store as long as we do the two halves in the right order
* with a barrier in between.
* In the percpu case, we also fallback to the simple update
*/
- if (percpu) {
- *ptep = pte;
+ if (IS_ENABLED(CONFIG_PPC32) && IS_ENABLED(CONFIG_PTE_64BIT) && !percpu) {
+ __asm__ __volatile__("\
+ stw%U0%X0 %2,%0\n\
+ eieio\n\
+ stw%U0%X0 %L2,%1"
+ : "=m" (*ptep), "=m" (*((unsigned char *)ptep+4))
+ : "r" (pte) : "memory");
return;
}
- __asm__ __volatile__("\
- stw%U0%X0 %2,%0\n\
- eieio\n\
- stw%U0%X0 %L2,%1"
- : "=m" (*ptep), "=m" (*((unsigned char *)ptep+4))
- : "r" (pte) : "memory");
-
-#else
/* Anything else just stores the PTE normally. That covers all 64-bit
* cases, and 32-bit non-hash with 32-bit PTEs.
*/
*ptep = pte;

-#ifdef CONFIG_PPC_BOOK3E_64
/*
* With hardware tablewalk, a sync is needed to ensure that
* subsequent accesses see the PTE we just wrote. Unlike userspace
* mappings, we can't tolerate spurious faults, so make sure
* the new PTE will be seen the first time.
*/
- if (is_kernel_addr(addr))
+ if (IS_ENABLED(CONFIG_PPC_BOOK3E_64) && is_kernel_addr(addr))
mb();
-#endif
-#endif
}


--
2.13.3