From c367a44133bcd7f94fb48b58e991dbffe7c25e22 Mon Sep 17 00:00:00 2001 From: "Aneesh Kumar K.V" Date: Tue, 1 Mar 2016 12:59:18 +0530 Subject: [PATCH] powerpc/mm: add _PAGE_HASHPTE similar to 4K hash 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 Signed-off-by: Michael Ellerman --- 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, -- 2.20.1