[PATCH 2/8] powerpc/mm: add _PAGE_HASHPTE similar to 4K hash

[Aneesh Kumar K.V]

We don't need to update linux page table entry with _PAGE_HASHPTE early
in hash pte fault. A parallel pte update will loop via _PAGE_BUSY
and look at _PAGE_HASHPTE for a required hpte flush only if
_PAGE_BUSY is cleared. That ensures a pte update will wait for a
parallel hpte insert to finish before looking at _PAGE_HASHPTE bit.

To avoid further confusion drop setting _PAGE_HASHPTE in cmpxchg in __hash_page_4K.

commit 41743a4e34f0 ("powerpc: Free a PTE bit on ppc64 with 64K pages")
did similar change for 64K config

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar at linux.vnet.ibm.com>
---
 arch/powerpc/mm/hash64_4k.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/powerpc/mm/hash64_4k.c b/arch/powerpc/mm/hash64_4k.c
index e3e76b929f33..47d1b26effc6 100644
--- a/arch/powerpc/mm/hash64_4k.c
+++ b/arch/powerpc/mm/hash64_4k.c
@@ -44,7 +44,7 @@ int __hash_page_4K(unsigned long ea, unsigned long access, unsigned long vsid,
 		 * a write access. Since this is 4K insert of 64K page size
 		 * also add _PAGE_COMBO
 		 */
-		new_pte = old_pte | _PAGE_BUSY | _PAGE_ACCESSED | _PAGE_HASHPTE;
+		new_pte = old_pte | _PAGE_BUSY | _PAGE_ACCESSED;
 		if (access & _PAGE_RW)
 			new_pte |= _PAGE_DIRTY;
 	} while (old_pte != __cmpxchg_u64((unsigned long *)ptep,
-- 
2.5.0