From: Yang Shi <yang.shi@xxxxxxxxxxxxxxxxx>
Subject: mm: thp: remove debug_cow switch
Since commit 3917c80280c93a7123f ("thp: change CoW semantics for
anon-THP"), the CoW page fault of THP has been rewritten, debug_cow is not
used anymore. So, just remove it.
Link: http://lkml.kernel.org/r/1592270980-116062-1-git-send-email-yang.shi@xxxxxxxxxxxxxxxxx
Signed-off-by: Yang Shi <yang.shi@xxxxxxxxxxxxxxxxx>
Reviewed-by: Zi Yan <ziy@xxxxxxxxxx>
Cc: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/linux/huge_mm.h | 7 -------
mm/huge_memory.c | 21 ---------------------
2 files changed, 28 deletions(-)
--- a/include/linux/huge_mm.h~mm-thp-remove-debug_cow-switch
+++ a/include/linux/huge_mm.h
@@ -181,13 +181,6 @@ static inline bool transhuge_vma_suitabl
#define transparent_hugepage_use_zero_page() \
(transparent_hugepage_flags & \
(1<<TRANSPARENT_HUGEPAGE_USE_ZERO_PAGE_FLAG))
-#ifdef CONFIG_DEBUG_VM
-#define transparent_hugepage_debug_cow() \
- (transparent_hugepage_flags & \
- (1<<TRANSPARENT_HUGEPAGE_DEBUG_COW_FLAG))
-#else /* CONFIG_DEBUG_VM */
-#define transparent_hugepage_debug_cow() 0
-#endif /* CONFIG_DEBUG_VM */
extern unsigned long thp_get_unmapped_area(struct file *filp,
unsigned long addr, unsigned long len, unsigned long pgoff,
--- a/mm/huge_memory.c~mm-thp-remove-debug_cow-switch
+++ a/mm/huge_memory.c
@@ -303,24 +303,6 @@ static ssize_t hpage_pmd_size_show(struc
static struct kobj_attribute hpage_pmd_size_attr =
__ATTR_RO(hpage_pmd_size);
-#ifdef CONFIG_DEBUG_VM
-static ssize_t debug_cow_show(struct kobject *kobj,
- struct kobj_attribute *attr, char *buf)
-{
- return single_hugepage_flag_show(kobj, attr, buf,
- TRANSPARENT_HUGEPAGE_DEBUG_COW_FLAG);
-}
-static ssize_t debug_cow_store(struct kobject *kobj,
- struct kobj_attribute *attr,
- const char *buf, size_t count)
-{
- return single_hugepage_flag_store(kobj, attr, buf, count,
- TRANSPARENT_HUGEPAGE_DEBUG_COW_FLAG);
-}
-static struct kobj_attribute debug_cow_attr =
- __ATTR(debug_cow, 0644, debug_cow_show, debug_cow_store);
-#endif /* CONFIG_DEBUG_VM */
-
static struct attribute *hugepage_attr[] = {
&enabled_attr.attr,
&defrag_attr.attr,
@@ -329,9 +311,6 @@ static struct attribute *hugepage_attr[]
#ifdef CONFIG_SHMEM
&shmem_enabled_attr.attr,
#endif
-#ifdef CONFIG_DEBUG_VM
- &debug_cow_attr.attr,
-#endif
NULL,
};
_
