There is only one user of hugetlb_optimize_vmemmap_enabled() outside of
hugetlb_vmemmap, that is flush_dcache_page() in arch/arm64/mm/flush.c.
However, it does not need to call hugetlb_optimize_vmemmap_enabled()
in flush_dcache_page() since HugeTLB pages are always fully mapped
and only head page will be set PG_dcache_clean meaning only head page
's flag may need to be cleared (see commit cf5a501d985b). After this
change, there is no users of hugetlb_optimize_vmemmap_enabled() outside
of hugetlb_vmemmap. So remove hugetlb_optimize_vmemmap_enabled() to
simplify the code.
Signed-off-by: Muchun Song <songmuchun@xxxxxxxxxxxxx>
Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
Cc: Will Deacon <will@xxxxxxxxxx>
Cc: Anshuman Khandual <anshuman.khandual@xxxxxxx>
---
arch/arm64/mm/flush.c | 13 +++----------
include/linux/page-flags.h | 14 ++------------
mm/hugetlb_vmemmap.c | 3 ++-
3 files changed, 7 insertions(+), 23 deletions(-)
diff --git a/arch/arm64/mm/flush.c b/arch/arm64/mm/flush.c
index fc4f710e9820..5f9379b3c8c8 100644
--- a/arch/arm64/mm/flush.c
+++ b/arch/arm64/mm/flush.c
@@ -76,17 +76,10 @@ EXPORT_SYMBOL_GPL(__sync_icache_dcache);
void flush_dcache_page(struct page *page)
{
/*
- * Only the head page's flags of HugeTLB can be cleared since the tail
- * vmemmap pages associated with each HugeTLB page are mapped with
- * read-only when CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP is enabled (more
- * details can refer to vmemmap_remap_pte()). Although
- * __sync_icache_dcache() only set PG_dcache_clean flag on the head
- * page struct, there is more than one page struct with PG_dcache_clean
- * associated with the HugeTLB page since the head vmemmap page frame
- * is reused (more details can refer to the comments above
- * page_fixed_fake_head()).
+ * HugeTLB pages are always fully mapped and only head page will be
+ * set PG_dcache_clean (see comments in __sync_icache_dcache()).
*/
- if (hugetlb_optimize_vmemmap_enabled() && PageHuge(page))
+ if (PageHuge(page))
page = compound_head(page);
if (test_bit(PG_dcache_clean, &page->flags))
diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h
index b70124b9c7c1..404f4ede17f5 100644
--- a/include/linux/page-flags.h
+++ b/include/linux/page-flags.h
@@ -203,12 +203,6 @@ enum pageflags {
DECLARE_STATIC_KEY_MAYBE(CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP_DEFAULT_ON,
hugetlb_optimize_vmemmap_key);
-static __always_inline bool hugetlb_optimize_vmemmap_enabled(void)
-{
- return static_branch_maybe(CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP_DEFAULT_ON,
- &hugetlb_optimize_vmemmap_key);
-}
-
/*
* If the feature of optimizing vmemmap pages associated with each HugeTLB
* page is enabled, the head vmemmap page frame is reused and all of the tail
@@ -227,7 +221,8 @@ static __always_inline bool hugetlb_optimize_vmemmap_enabled(void)
*/
static __always_inline const struct page *page_fixed_fake_head(const struct page *page)
{
- if (!hugetlb_optimize_vmemmap_enabled())
+ if (!static_branch_maybe(CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP_DEFAULT_ON,
+ &hugetlb_optimize_vmemmap_key))
return page;
/*
@@ -255,11 +250,6 @@ static inline const struct page *page_fixed_fake_head(const struct page *page)
{
return page;
}
-
-static inline bool hugetlb_optimize_vmemmap_enabled(void)
-{
- return false;
-}
#endif
static __always_inline int page_is_fake_head(struct page *page)
diff --git a/mm/hugetlb_vmemmap.c b/mm/hugetlb_vmemmap.c
index 970c36b8935f..d1fea65fec98 100644
--- a/mm/hugetlb_vmemmap.c
+++ b/mm/hugetlb_vmemmap.c
@@ -124,7 +124,8 @@ void __init hugetlb_vmemmap_init(struct hstate *h)
BUILD_BUG_ON(__NR_USED_SUBPAGE >=
RESERVE_VMEMMAP_SIZE / sizeof(struct page));
- if (!hugetlb_optimize_vmemmap_enabled())
+ if (!static_branch_maybe(CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP_DEFAULT_ON,
+ &hugetlb_optimize_vmemmap_key))
return;
if (!is_power_of_2(sizeof(struct page))) {
--
2.11.0
