In order to minimize code size (CONFIG_CC_OPTIMIZE_FOR_SIZE=y),
compiler might choose to make a regular function call (out-of-line) for
shmem_is_huge() instead of inlining it. When transparent hugepages are
disabled (CONFIG_TRANSPARENT_HUGEPAGE=n), it can cause compilation
error.
mm/shmem.c: In function ‘shmem_getattr’:
./include/linux/huge_mm.h:383:27: note: in expansion of macro ‘BUILD_BUG’
383 | #define HPAGE_PMD_SIZE ({ BUILD_BUG(); 0; })
| ^~~~~~~~~
mm/shmem.c:1148:33: note: in expansion of macro ‘HPAGE_PMD_SIZE’
1148 | stat->blksize = HPAGE_PMD_SIZE;
To prevent the possible error, always inline shmem_is_huge() when
transparent hugepages are disabled.
Signed-off-by: Sumanth Korikkar <sumanthk@xxxxxxxxxxxxx>
---
include/linux/shmem_fs.h | 9 +++++++++
mm/shmem.c | 6 ------
2 files changed, 9 insertions(+), 6 deletions(-)
diff --git a/include/linux/shmem_fs.h b/include/linux/shmem_fs.h
index a4c15db2f5e5..3fb18f7eb73e 100644
--- a/include/linux/shmem_fs.h
+++ b/include/linux/shmem_fs.h
@@ -110,8 +110,17 @@ extern struct page *shmem_read_mapping_page_gfp(struct address_space *mapping,
extern void shmem_truncate_range(struct inode *inode, loff_t start, loff_t end);
int shmem_unuse(unsigned int type);
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
extern bool shmem_is_huge(struct inode *inode, pgoff_t index, bool shmem_huge_force,
struct mm_struct *mm, unsigned long vm_flags);
+#else
+static __always_inline bool shmem_is_huge(struct inode *inode, pgoff_t index, bool shmem_huge_force,
+ struct mm_struct *mm, unsigned long vm_flags)
+{
+ return false;
+}
+#endif
+
#ifdef CONFIG_SHMEM
extern unsigned long shmem_swap_usage(struct vm_area_struct *vma);
#else
diff --git a/mm/shmem.c b/mm/shmem.c
index 0aad0d9a621b..94ab99b6b574 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -748,12 +748,6 @@ static long shmem_unused_huge_count(struct super_block *sb,
#define shmem_huge SHMEM_HUGE_DENY
-bool shmem_is_huge(struct inode *inode, pgoff_t index, bool shmem_huge_force,
- struct mm_struct *mm, unsigned long vm_flags)
-{
- return false;
-}
-
static unsigned long shmem_unused_huge_shrink(struct shmem_sb_info *sbinfo,
struct shrink_control *sc, unsigned long nr_to_split)
{
--
2.40.1
