[032/131] mm/page_alloc.c: bad_[reason|flags] is not necessary when PageHWPoison

Commit Message

Andrew Morton June 3, 2020, 10:58 p.m. UTC

From: Wei Yang <[e-mail]>
Subject: 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")

Link: http://lkml.kernel.org/r/[e-mail]
Signed-off-by: Wei Yang <[e-mail]>
Acked-by: Michal Hocko <[e-mail]>
Reviewed-by: David Hildenbrand <[e-mail]>
Cc: Anshuman Khandual <[e-mail]>
Cc: David Rientjes <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
---

 mm/page_alloc.c |   12 +++++-------
 1 file changed, 5 insertions(+), 7 deletions(-)

Patch

--- a/mm/page_alloc.c~mm-page_allocc-bad_-is-not-necessary-when-pagehwpoison
+++ a/mm/page_alloc.c
@@ -2097,19 +2097,17 @@  static void check_new_page_bad(struct pa
 	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;