mm, page_alloc: un-inline the bad part of free_pages_check

From: Vlastimil Babka <vbabka@suse.cz>

!DEBUG_VM size and bloat-o-meter:

  add/remove: 1/0 grow/shrink: 0/2 up/down: 124/-370 (-246)
  function                                     old     new   delta
  free_pages_check_bad                           -     124    +124
  free_pcppages_bulk                          1288    1171    -117
  __free_pages_ok                              948     695    -253

DEBUG_VM:

  add/remove: 1/0 grow/shrink: 0/1 up/down: 124/-214 (-90)
  function                                     old     new   delta
  free_pages_check_bad                           -     124    +124
  free_pages_prepare                          1112     898    -214

[akpm@linux-foundation.org: fix whitespace]
Signed-off-by: NVlastimil Babka <vbabka@suse.cz>
Signed-off-by: NMel Gorman <mgorman@techsingularity.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

mm/page_alloc.c

@@ -806,18 +806,11 @@ static inline bool page_expected_state(struct page *page,
 	return true;
 }
 
-static inline int free_pages_check(struct page *page)
+static void free_pages_check_bad(struct page *page)
 {
 	const char *bad_reason;
 	unsigned long bad_flags;
 
-	if (page_expected_state(page, PAGE_FLAGS_CHECK_AT_FREE)) {
-		page_cpupid_reset_last(page);
-		page->flags &= ~PAGE_FLAGS_CHECK_AT_PREP;
-		return 0;
-	}
-
-	/* Something has gone sideways, find it */
 	bad_reason = NULL;
 	bad_flags = 0;
 
@@ -836,6 +829,18 @@ static inline int free_pages_check(struct page *page)
 		bad_reason = "page still charged to cgroup";
 #endif
 	bad_page(page, bad_reason, bad_flags);
+}
+
+static inline int free_pages_check(struct page *page)
+{
+	if (likely(page_expected_state(page, PAGE_FLAGS_CHECK_AT_FREE))) {
+		page_cpupid_reset_last(page);
+		page->flags &= ~PAGE_FLAGS_CHECK_AT_PREP;
+		return 0;
+	}
+
+	/* Something has gone sideways, find it */
+	free_pages_check_bad(page);
 	return 1;
 }