powerpc/mm: use _raw variant of page table accessors
authorAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Wed, 13 Jul 2016 09:35:22 +0000 (15:05 +0530)
committerMichael Ellerman <mpe@ellerman.id.au>
Sun, 17 Jul 2016 06:42:51 +0000 (16:42 +1000)
commit66c570f545e056babdd9510595ce762dcedadd71
tree4d72435c8b6fd348562c5fb3f7ed93fc410e1e51
parentbf16cdf48a5369ba29614a0ade4ae5daf7a9e47c
powerpc/mm: use _raw variant of page table accessors

This switch few of the page table accessor to use the __raw variant
and does the cpu to big endian conversion of constants. This helps in
generating better code.

For ex: a pgd_none(pgd) check with and without fix is listed below

Without fix:
------------
   2240: 20 00 61 eb  ld      r27,32(r1)
/* PGD level */
typedef struct { __be64 pgd; } pgd_t;
static inline unsigned long pgd_val(pgd_t x)
{
return be64_to_cpu(x.pgd);

    2244: 22 00 66 78  rldicl  r6,r3,32,32
    2248: 3e 40 7d 54  rotlwi  r29,r3,8
    224c: 0e c0 7d 50  rlwimi  r29,r3,24,0,7
    2250: 3e 40 c5 54  rotlwi  r5,r6,8
    2254: 2e c4 7d 50  rlwimi  r29,r3,24,16,23
    2258: 0e c0 c5 50  rlwimi  r5,r6,24,0,7
    225c: 2e c4 c5 50  rlwimi  r5,r6,24,16,23
    2260: c6 07 bd 7b  rldicr  r29,r29,32,31
    2264: 78 2b bd 7f  or      r29,r29,r5
if (pgd_none(pgd))
    2268: 00 00 bd 2f  cmpdi   cr7,r29,0
    226c: 54 03 9e 41  beq     cr7,25c0 <__get_user_pages_fast+0x500>

With fix:
---------
    2370: 20 00 61 eb  ld      r27,32(r1)
if (pgd_none(pgd))
    2374: 00 00 bd 2f  cmpdi   cr7,r29,0
    2378: a8 03 9e 41  beq     cr7,2720 <__get_user_pages_fast+0x530>
break;
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Acked-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
arch/powerpc/include/asm/book3s/64/pgtable-4k.h
arch/powerpc/include/asm/book3s/64/pgtable-64k.h
arch/powerpc/include/asm/book3s/64/pgtable.h
arch/powerpc/include/asm/pgtable-be-types.h