[PATCH 3.2 22/46] mm: hugetlb: allow hugepages_supported to be architecture specific

Ben Hutchings
2016-06-12T21:35:55Z

From: Dominik Dingel <dingel@linux.vnet.ibm.com>

commit 2531c8cf56a640cd7d17057df8484e570716a450 upstream.

s390 has a constant hugepage size, by setting HPAGE_SHIFT we also change
e.g. the pageblock_order, which should be independent in respect to
hugepage support.

With this patch every architecture is free to define how to check
for hugepage support.

Signed-off-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Cc: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
include/linux/hugetlb.h | 17 ++++++++---------
1 file changed, 8 insertions(+), 9 deletions(-)

--- a/include/linux/hugetlb.h
+++ b/include/linux/hugetlb.h
@@ -344,15 +344,14 @@ static inline pgoff_t basepage_index(str
return __basepage_index(page);
}

-static inline bool hugepages_supported(void)
-{
- /*
- * Some platform decide whether they support huge pages at boot
- * time. On these, such as powerpc, HPAGE_SHIFT is set to 0 when
- * there is no such support
- */
- return HPAGE_SHIFT != 0;
-}
+#ifndef hugepages_supported
+/*
+ * Some platform decide whether they support huge pages at boot
+ * time. Some of them, such as powerpc, set HPAGE_SHIFT to 0
+ * when there is no such support
+ */
+#define hugepages_supported() (HPAGE_SHIFT != 0)
+#endif

#else
struct hstate {};