[v2 PATCH] mm: rmap: use VM_BUG_ON_PAGE() in __page_check_anon_rmap()

From: Yang Shi
Date: Thu Nov 07 2019 - 15:09:16 EST


The __page_check_anon_rmap() just calls two BUG_ON()s protected by
CONFIG_DEBUG_VM, the #ifdef could be eliminated by using VM_BUG_ON_PAGE().

Cc: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
Signed-off-by: Yang Shi <yang.shi@xxxxxxxxxxxxxxxxx>
---
v2: Use VM_BUG_ON_PAGE() per Kirill and update the subject accordingly.

mm/rmap.c | 7 +++----
1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/mm/rmap.c b/mm/rmap.c
index d17cbf3..71d58d6 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -1055,7 +1055,6 @@ static void __page_set_anon_rmap(struct page *page,
static void __page_check_anon_rmap(struct page *page,
struct vm_area_struct *vma, unsigned long address)
{
-#ifdef CONFIG_DEBUG_VM
/*
* The page's anon-rmap details (mapping and index) are guaranteed to
* be set up correctly at this point.
@@ -1068,9 +1067,9 @@ static void __page_check_anon_rmap(struct page *page,
* are initially only visible via the pagetables, and the pte is locked
* over the call to page_add_new_anon_rmap.
*/
- BUG_ON(page_anon_vma(page)->root != vma->anon_vma->root);
- BUG_ON(page_to_pgoff(page) != linear_page_index(vma, address));
-#endif
+ VM_BUG_ON_PAGE(page_anon_vma(page)->root != vma->anon_vma->root, page);
+ VM_BUG_ON_PAGE(page_to_pgoff(page) != linear_page_index(vma, address),
+ page);
}

/**
--
1.8.3.1