mm: meminit: remove mminit_verify_page_links

mminit_verify_page_links() is an extremely paranoid check that was introduced when memory initialisation was being heavily reworked. Profiles indicated that up to 10% of parallel memory initialisation was spent on checking this for every page. The cost could be reduced but in practice this check only found problems very early during the initialisation rewrite and has found nothing since. This patch removes an expensive unnecessary check. Signed-off-by: Mel Gorman <[email protected]> Tested-by: Nate Zimmer <[email protected]> Tested-by: Waiman Long <[email protected]> Tested-by: Daniel J Blueman <[email protected]> Acked-by: Pekka Enberg <[email protected]> Cc: Robin Holt <[email protected]> Cc: Nate Zimmer <[email protected]> Cc: Dave Hansen <[email protected]> Cc: Waiman Long <[email protected]> Cc: Scott Norton <[email protected]> Cc: "Luck, Tony" <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: "H. Peter Anvin" <[email protected]> Cc: Thomas Gleixner <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
mrcsosa · Jul 1, 2015 · 74033a7 · 74033a7
1 parent ac5d253
commit 74033a7
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Showing 3 changed files with 0 additions and 17 deletions.
diff --git a/mm/internal.h b/mm/internal.h
@@ -362,10 +362,7 @@ do { \
 } while (0)
 
 extern void mminit_verify_pageflags_layout(void);
-extern void mminit_verify_page_links(struct page *page,
-		enum zone_type zone, unsigned long nid, unsigned long pfn);
 extern void mminit_verify_zonelist(void);
-
 #else
 
 static inline void mminit_dprintk(enum mminit_level level,
@@ -377,11 +374,6 @@ static inline void mminit_verify_pageflags_layout(void)
 {
 }
 
-static inline void mminit_verify_page_links(struct page *page,
-		enum zone_type zone, unsigned long nid, unsigned long pfn)
-{
-}
-
 static inline void mminit_verify_zonelist(void)
 {
 }

diff --git a/mm/mm_init.c b/mm/mm_init.c
@@ -131,14 +131,6 @@ void __init mminit_verify_pageflags_layout(void)
 	BUG_ON(or_mask != add_mask);
 }
 
-void __meminit mminit_verify_page_links(struct page *page, enum zone_type zone,
-			unsigned long nid, unsigned long pfn)
-{
-	BUG_ON(page_to_nid(page) != nid);
-	BUG_ON(page_zonenum(page) != zone);
-	BUG_ON(page_to_pfn(page) != pfn);
-}
-
 static __init int set_mminit_loglevel(char *str)
 {
 	get_option(&str, &mminit_loglevel);

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
@@ -839,7 +839,6 @@ static void __meminit __init_single_page(struct page *page, unsigned long pfn,
 				unsigned long zone, int nid)
 {
 	set_page_links(page, zone, nid, pfn);
-	mminit_verify_page_links(page, zone, nid, pfn);
 	init_page_count(page);
 	page_mapcount_reset(page);
 	page_cpupid_reset_last(page);