Merge branch 'akpm' (patches from Andrew)

Merge misc updates from Andrew Morton:
 "146 patches.

  Subsystems affected by this patch series: kthread, ia64, scripts,
  ntfs, squashfs, ocfs2, vfs, and mm (slab-generic, slab, kmemleak,
  dax, kasan, debug, pagecache, gup, shmem, frontswap, memremap,
  memcg, selftests, pagemap, dma, vmalloc, memory-failure, hugetlb,
  userfaultfd, vmscan, mempolicy, oom-kill, hugetlbfs, migration, thp,
  ksm, page-poison, percpu, rmap, zswap, zram, cleanups, hmm, and
  damon)"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (146 commits)
  mm/damon: hide kernel pointer from tracepoint event
  mm/damon/vaddr: hide kernel pointer from damon_va_three_regions() failure log
  mm/damon/vaddr: use pr_debug() for damon_va_three_regions() failure logging
  mm/damon/dbgfs: remove an unnecessary variable
  mm/damon: move the implementation of damon_insert_region to damon.h
  mm/damon: add access checking for hugetlb pages
  Docs/admin-guide/mm/damon/usage: update for schemes statistics
  mm/damon/dbgfs: support all DAMOS stats
  Docs/admin-guide/mm/damon/reclaim: document statistics parameters
  mm/damon/reclaim: provide reclamation statistics
  mm/damon/schemes: account how many times quota limit has exceeded
  mm/damon/schemes: account scheme actions that successfully applied
  mm/damon: remove a mistakenly added comment for a future feature
  Docs/admin-guide/mm/damon/usage: update for kdamond_pid and (mk|rm)_contexts
  Docs/admin-guide/mm/damon/usage: mention tracepoint at the beginning
  Docs/admin-guide/mm/damon/usage: remove redundant information
  Docs/admin-guide/mm/damon/usage: update for scheme quotas and watermarks
  mm/damon: convert macro functions to static inline functions
  mm/damon: modify damon_rand() macro to static inline function
  mm/damon: move damon_rand() definition into damon.h
  ...

1 files changed, 15 insertions, 29 deletions

diff --git a/mm/swapfile.c b/mm/swapfile.c
index e59e08ef46e1..caa9f81a0d15 100644
--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -1601,31 +1601,30 @@ static bool page_swapped(struct page *page)
 	return false;
 }
 
-static int page_trans_huge_map_swapcount(struct page *page, int *total_mapcount,
+static int page_trans_huge_map_swapcount(struct page *page,
 					 int *total_swapcount)
 {
-	int i, map_swapcount, _total_mapcount, _total_swapcount;
+	int i, map_swapcount, _total_swapcount;
 	unsigned long offset = 0;
 	struct swap_info_struct *si;
 	struct swap_cluster_info *ci = NULL;
 	unsigned char *map = NULL;
-	int mapcount, swapcount = 0;
+	int swapcount = 0;
 
 	/* hugetlbfs shouldn't call it */
 	VM_BUG_ON_PAGE(PageHuge(page), page);
 
 	if (!IS_ENABLED(CONFIG_THP_SWAP) || likely(!PageTransCompound(page))) {
-		mapcount = page_trans_huge_mapcount(page, total_mapcount);
 		if (PageSwapCache(page))
 			swapcount = page_swapcount(page);
 		if (total_swapcount)
 			*total_swapcount = swapcount;
-		return mapcount + swapcount;
+		return swapcount + page_trans_huge_mapcount(page);
 	}
 
 	page = compound_head(page);
 
-	_total_mapcount = _total_swapcount = map_swapcount = 0;
+	_total_swapcount = map_swapcount = 0;
 	if (PageSwapCache(page)) {
 		swp_entry_t entry;
 
@@ -1639,8 +1638,7 @@ static int page_trans_huge_map_swapcount(struct page *page, int *total_mapcount,
 	if (map)
 		ci = lock_cluster(si, offset);
 	for (i = 0; i < HPAGE_PMD_NR; i++) {
-		mapcount = atomic_read(&page[i]._mapcount) + 1;
-		_total_mapcount += mapcount;
+		int mapcount = atomic_read(&page[i]._mapcount) + 1;
 		if (map) {
 			swapcount = swap_count(map[offset + i]);
 			_total_swapcount += swapcount;
@@ -1648,19 +1646,14 @@ static int page_trans_huge_map_swapcount(struct page *page, int *total_mapcount,
 		map_swapcount = max(map_swapcount, mapcount + swapcount);
 	}
 	unlock_cluster(ci);
-	if (PageDoubleMap(page)) {
+
+	if (PageDoubleMap(page))
 		map_swapcount -= 1;
-		_total_mapcount -= HPAGE_PMD_NR;
-	}
-	mapcount = compound_mapcount(page);
-	map_swapcount += mapcount;
-	_total_mapcount += mapcount;
-	if (total_mapcount)
-		*total_mapcount = _total_mapcount;
+
 	if (total_swapcount)
 		*total_swapcount = _total_swapcount;
 
-	return map_swapcount;
+	return map_swapcount + compound_mapcount(page);
 }
 
 /*
@@ -1668,22 +1661,15 @@ static int page_trans_huge_map_swapcount(struct page *page, int *total_mapcount,
  * to it.  And as a side-effect, free up its swap: because the old content
  * on disk will never be read, and seeking back there to write new content
  * later would only waste time away from clustering.
- *
- * NOTE: total_map_swapcount should not be relied upon by the caller if
- * reuse_swap_page() returns false, but it may be always overwritten
- * (see the other implementation for CONFIG_SWAP=n).
  */
-bool reuse_swap_page(struct page *page, int *total_map_swapcount)
+bool reuse_swap_page(struct page *page)
 {
-	int count, total_mapcount, total_swapcount;
+	int count, total_swapcount;
 
 	VM_BUG_ON_PAGE(!PageLocked(page), page);
 	if (unlikely(PageKsm(page)))
 		return false;
-	count = page_trans_huge_map_swapcount(page, &total_mapcount,
-					      &total_swapcount);
-	if (total_map_swapcount)
-		*total_map_swapcount = total_mapcount + total_swapcount;
+	count = page_trans_huge_map_swapcount(page, &total_swapcount);
 	if (count == 1 && PageSwapCache(page) &&
 	    (likely(!PageTransCompound(page)) ||
 	     /* The remaining swap count will be freed soon */
@@ -1917,14 +1903,14 @@ static int unuse_pte(struct vm_area_struct *vma, pmd_t *pmd,
 	dec_mm_counter(vma->vm_mm, MM_SWAPENTS);
 	inc_mm_counter(vma->vm_mm, MM_ANONPAGES);
 	get_page(page);
-	set_pte_at(vma->vm_mm, addr, pte,
-		   pte_mkold(mk_pte(page, vma->vm_page_prot)));
 	if (page == swapcache) {
 		page_add_anon_rmap(page, vma, addr, false);
 	} else { /* ksm created a completely new copy */
 		page_add_new_anon_rmap(page, vma, addr, false);
 		lru_cache_add_inactive_or_unevictable(page, vma);
 	}
+	set_pte_at(vma->vm_mm, addr, pte,
+		   pte_mkold(mk_pte(page, vma->vm_page_prot)));
 	swap_free(entry);
 out:
 	pte_unmap_unlock(pte, ptl);