[PATCH] mm: ptd_alloc inline and out

It seems odd to me that, whereas pud_alloc and pmd_alloc test inline, only
calling out-of-line __pud_alloc __pmd_alloc if allocation needed,
pte_alloc_map and pte_alloc_kernel are entirely out-of-line.  Though it does
add a little to kernel size, change them to macros testing inline, calling
__pte_alloc or __pte_alloc_kernel to allocate out-of-line.  Mark none of them
as fastcalls, leave that to CONFIG_REGPARM or not.

It also seems more natural for the out-of-line functions to leave the offset
calculation and map to the inline, which has to do it anyway for the common
case.  At least mremap move wants __pte_alloc without _map.

Macros rather than inline functions, certainly to avoid the header file issues
which arise from CONFIG_HIGHPTE needing kmap_types.h, but also in case any
architectures I haven't built would have other such problems.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 3 insertions, 8 deletions

diff --git a/include/asm-generic/4level-fixup.h b/include/asm-generic/4level-fixup.h
index c20ec257ecc0..68c6fea994d9 100644
--- a/include/asm-generic/4level-fixup.h
+++ b/include/asm-generic/4level-fixup.h
@@ -10,14 +10,9 @@
 
 #define pud_t                           pgd_t
 
-#define pmd_alloc(mm, pud, address)                     \
-({      pmd_t *ret;                                     \
-        if (pgd_none(*pud))                             \
-                ret = __pmd_alloc(mm, pud, address);    \
-        else                                            \
-                ret = pmd_offset(pud, address);         \
-        ret;                                            \
-})
+#define pmd_alloc(mm, pud, address) \
+        ((unlikely(pgd_none(*(pud))) && __pmd_alloc(mm, pud, address))? \
+                NULL: pmd_offset(pud, address))
 
 #define pud_alloc(mm, pgd, address)     (pgd)
 #define pud_offset(pgd, start)          (pgd)