"Naveen N. Rao" [off-list ref] writes:

On 2017/06/19 03:21PM, Aneesh Kumar K.V wrote:

quoted

quoted

@@ -1445,8 +1446,8 @@ do_hash_page:
 handle_page_fault:
 	andis.  r0,r4,DSISR_DABRMATCH@h
 	bne-    handle_dabr_fault
-	ld	r4,_DAR(r1)
-	ld	r5,_DSISR(r1)
+	mr	r5,r4
+	mr	r4,r3
 	addi	r3,r1,STACK_FRAME_OVERHEAD
 	bl	do_page_fault
 	cmpdi	r3,0

Can we avoid that if we rearrange args of other functions calls, so that
we can use r3 and r4 as it is ?

Here's a version that does that. Again, boot tested with radix and 
disable_radix.

Thanks,
Naveen

-
Change data_access_common() and instruction_access_common() to load the
trap number in r3, DAR in r4 and DSISR in r5 (rather than in r5, r3 and
r4 respectively). This change allows us to eliminate a few un-necessary
memory loads and register move operations in handle_page_fault(),
handle_dabr_fault() and label '77'.

Signed-off-by: Naveen N. Rao <redacted>
---
 arch/powerpc/kernel/exceptions-64s.S | 38 +++++++++++++++++-------------------
 1 file changed, 18 insertions(+), 20 deletions(-)

Sorry I missed this and now it doesn't apply. Do you mind rebasing.

cheers