mm/page_alloc.c: bad_[reason|flags] is not necessary when PageHWPoison

Patch series "mm/page_alloc.c: cleanup on check page", v3.

This patchset does some cleanup related to check page.

1. Remove unnecessary bad_reason assignment
2. Remove bad_flags to bad_page()
3. Rename function for naming convention
4. Extract common part to check page

Thanks for suggestions from David Rientjes and Anshuman Khandual.

This patch (of 5):

Since function returns directly, bad_[reason|flags] is not used any where.
And move this to the first.

This is a following cleanup for commit e570f56cccd21 ("mm:
check_new_page_bad() directly returns in __PG_HWPOISON case")

Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: David Rientjes <rientjes@google.com>
Link: http://lkml.kernel.org/r/20200411220357.9636-2-richard.weiyang@gmail.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 0a2a67c7f230731a808022ea3f52155bfbb44e23..3ef7db15ec70d3842ad9dda82d99b8f8275272bb 100644 (file)
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -2097,19 +2097,17 @@ static void check_new_page_bad(struct page *page)
        const char *bad_reason = NULL;
        unsigned long bad_flags = 0;
 
+       if (unlikely(page->flags & __PG_HWPOISON)) {
+               /* Don't complain about hwpoisoned pages */
+               page_mapcount_reset(page); /* remove PageBuddy */
+               return;
+       }
        if (unlikely(atomic_read(&page->_mapcount) != -1))
                bad_reason = "nonzero mapcount";
        if (unlikely(page->mapping != NULL))
                bad_reason = "non-NULL mapping";
        if (unlikely(page_ref_count(page) != 0))
                bad_reason = "nonzero _refcount";
-       if (unlikely(page->flags & __PG_HWPOISON)) {
-               bad_reason = "HWPoisoned (hardware-corrupted)";
-               bad_flags = __PG_HWPOISON;
-               /* Don't complain about hwpoisoned pages */
-               page_mapcount_reset(page); /* remove PageBuddy */
-               return;
-       }
        if (unlikely(page->flags & PAGE_FLAGS_CHECK_AT_PREP)) {
                bad_reason = "PAGE_FLAGS_CHECK_AT_PREP flag set";
                bad_flags = PAGE_FLAGS_CHECK_AT_PREP;