Le 11/04/2018 à 11:03, Laurent Dufour a écrit :
On 11/04/2018 10:58, Christophe LEROY wrote:
Le 11/04/2018 à 10:03, Laurent Dufour a écrit :
Remove the additional define HAVE_PTE_SPECIAL and rely directly on
CONFIG_ARCH_HAS_PTE_SPECIAL.
There is no functional change introduced by this patch
Signed-off-by: Laurent Dufour <lduf...@linux.vnet.ibm.com>
---
mm/memory.c | 19 ++++++++-----------
1 file changed, 8 insertions(+), 11 deletions(-)
diff --git a/mm/memory.c b/mm/memory.c
index 96910c625daa..7f7dc7b2a341 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -817,17 +817,12 @@ static void print_bad_pte(struct vm_area_struct *vma,
unsigned long addr,
* PFNMAP mappings in order to support COWable mappings.
*
*/
-#ifdef CONFIG_ARCH_HAS_PTE_SPECIAL
-# define HAVE_PTE_SPECIAL 1
-#else
-# define HAVE_PTE_SPECIAL 0
-#endif
struct page *_vm_normal_page(struct vm_area_struct *vma, unsigned long addr,
pte_t pte, bool with_public_device)
{
unsigned long pfn = pte_pfn(pte);
- if (HAVE_PTE_SPECIAL) {
+ if (IS_ENABLED(CONFIG_ARCH_HAS_PTE_SPECIAL)) {
if (likely(!pte_special(pte)))
goto check_pfn;
if (vma->vm_ops && vma->vm_ops->find_special_page)
@@ -862,7 +857,7 @@ struct page *_vm_normal_page(struct vm_area_struct *vma,
unsigned long addr,
return NULL;
}
- /* !HAVE_PTE_SPECIAL case follows: */
+ /* !CONFIG_ARCH_HAS_PTE_SPECIAL case follows: */
if (unlikely(vma->vm_flags & (VM_PFNMAP|VM_MIXEDMAP))) {
if (vma->vm_flags & VM_MIXEDMAP) {
@@ -881,7 +876,8 @@ struct page *_vm_normal_page(struct vm_area_struct *vma,
unsigned long addr,
if (is_zero_pfn(pfn))
return NULL;
-check_pfn:
+
+check_pfn: __maybe_unused
See below
if (unlikely(pfn > highest_memmap_pfn)) {
print_bad_pte(vma, addr, pte, NULL);
return NULL;
@@ -891,7 +887,7 @@ struct page *_vm_normal_page(struct vm_area_struct *vma,
unsigned long addr,
* NOTE! We still have PageReserved() pages in the page tables.
* eg. VDSO mappings can cause them to exist.
*/
-out:
+out: __maybe_unused
Why do you need that change ?
There is no reason for the compiler to complain. It would complain if the goto
was within a #ifdef, but all the purpose of using IS_ENABLED() is to allow the
compiler to properly handle all possible cases. That's all the force of
IS_ENABLED() compared to ifdefs, and that the reason why they are plebicited,
ref Linux Codying style for a detailed explanation.
Fair enough.
Should I submit a v4 just to remove these so ugly __maybe_unused ?
Most likely, unless the mm maintainer agrees to remove them by himself
when applying your patch ?
Christophe
--
To unsubscribe from this list: send the line "unsubscribe linux-doc" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
