path: root/arch/powerpc/include
diff options
authorAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>2017-02-09 08:28:19 +0530
committerMichael Ellerman <mpe@ellerman.id.au>2017-02-15 20:02:40 +1100
commitca94573b9c69d224e50e1084a2776772f4ea030d (patch)
tree6cbe50dc5a4222c9f289819acb92f13eff5bf01b /arch/powerpc/include
parent18061c17c8ecdbdbf1e7d1695ec44e7388b4f601 (diff)
powerpc/mm/radix: Update pte update sequence for pte clear case
In the kernel we do follow the below sequence in different code paths. pte = ptep_get_clear(ptep) .... set_pte_at(ptep, pte) We do that for mremap, autonuma protection update and softdirty clearing. This implies our optimization to skip a tlb flush when clearing a pte update is not valid, because for DD1 system that followup set_pte_at will be done witout doing the required tlbflush. Fix that by always doing the dd1 style pte update irrespective of new_pte value. In a later patch we will optimize the application exit case. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> 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>
Diffstat (limited to 'arch/powerpc/include')
1 files changed, 3 insertions, 9 deletions
diff --git a/arch/powerpc/include/asm/book3s/64/radix.h b/arch/powerpc/include/asm/book3s/64/radix.h
index 0032b662284c..98c9ab37593c 100644
--- a/arch/powerpc/include/asm/book3s/64/radix.h
+++ b/arch/powerpc/include/asm/book3s/64/radix.h
@@ -144,16 +144,10 @@ static inline unsigned long radix__pte_update(struct mm_struct *mm,
* new value of pte
new_pte = (old_pte | set) & ~clr;
- /*
- * If we are trying to clear the pte, we can skip
- * the below sequence and batch the tlb flush. The
- * tlb flush batching is done by mmu gather code
- */
- if (new_pte) {
- asm volatile("ptesync" : : : "memory");
- radix__flush_tlb_pte_p9_dd1(old_pte, mm, addr);
+ 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");