powerpc/mm/radix: Skip ptesync in pte update helpers

BugLink: http://bugs.launchpad.net/bugs/1667116
We do them at the start of tlb flush, and we are sure a pte update will be
followed by a tlbflush. Hence we can skip the ptesync in pte update helpers.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Tested-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
(cherry picked from linux-next commit 438e69b52be776c035aa2a851ccc1709033d729b)
Signed-off-by: Seth Forshee <seth.forshee@canonical.com>

diff --git a/arch/powerpc/include/asm/book3s/64/radix.h b/arch/powerpc/include/asm/book3s/64/radix.h
index fcf822d6c204fa17f846b98e18a9ee28a45d08dc..77e590c77299a9445bed8ba598da4e090def4112 100644 (file)
--- a/arch/powerpc/include/asm/book3s/64/radix.h
+++ b/arch/powerpc/include/asm/book3s/64/radix.h
@@ -144,13 +144,11 @@ static inline unsigned long radix__pte_update(struct mm_struct *mm,
                 * new value of pte
                 */
                new_pte = (old_pte | set) & ~clr;
-               asm volatile("ptesync" : : : "memory");
                radix__flush_tlb_pte_p9_dd1(old_pte, mm, addr);
                if (new_pte)
                        __radix_pte_update(ptep, 0, new_pte);
        } else
                old_pte = __radix_pte_update(ptep, clr, set);
-       asm volatile("ptesync" : : : "memory");
        if (!huge)
                assert_pte_locked(mm, addr);
 
@@ -195,7 +193,6 @@ static inline void radix__ptep_set_access_flags(struct mm_struct *mm,
                unsigned long old_pte, new_pte;
 
                old_pte = __radix_pte_update(ptep, ~0, 0);
-               asm volatile("ptesync" : : : "memory");
                /*
                 * new value of pte
                 */