mm-mmzonec-use-try_cmpxchg-in-page_cpupid_xchg_last.patch removed from -mm tree

The patch titled
Subject: mm/mmzone.c: use try_cmpxchg() in page_cpupid_xchg_last()
has been removed from the -mm tree. Its filename was
mm-mmzonec-use-try_cmpxchg-in-page_cpupid_xchg_last.patch

This patch was dropped because it was merged into mainline or a subsystem tree

------------------------------------------------------
From: Peter Collingbourne <[email protected]>
Subject: mm/mmzone.c: use try_cmpxchg() in page_cpupid_xchg_last()

This will let us avoid an additional read from page->flags when retrying the compare-exchange on some architectures.

---

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

@@ -89,13 +89,14 @@ int page_cpupid_xchg_last(struct page *p
 	unsigned long old_flags, flags;
 	int last_cpupid;
 
+	old_flags = READ_ONCE(page->flags);
 	do {
-		old_flags = flags = page->flags;
-		last_cpupid = page_cpupid_last(page);
+		flags = old_flags;
+		last_cpupid = (flags >> LAST_CPUPID_PGSHIFT) & LAST_CPUPID_MASK;
 
 		flags &= ~(LAST_CPUPID_MASK << LAST_CPUPID_PGSHIFT);
 		flags |= (cpupid & LAST_CPUPID_MASK) << LAST_CPUPID_PGSHIFT;
-	} while (unlikely(cmpxchg(&page->flags, old_flags, flags) != old_flags));
+	} while (unlikely(!try_cmpxchg(&page->flags, &old_flags, flags)));
 
 	return last_cpupid;
 }

_

Patches currently in -mm which might be from [email protected] are

kasan-update-function-name-in-comments.patch