mm/hwpoison: fix refcount of THP head page in no-injection case

[deliverable/linux.git] / mm / vmscan.c

diff --git a/mm/vmscan.c b/mm/vmscan.c
index 99ec00d6a5dd6ed910c5935b957f301e58266830..8276a3a615ca0049515affe9adbd4a0480ce8c4a 100644 (file)
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -175,7 +175,7 @@ static bool sane_reclaim(struct scan_control *sc)
        if (!memcg)
                return true;
 #ifdef CONFIG_CGROUP_WRITEBACK
-       if (cgroup_on_dfl(mem_cgroup_css(memcg)->cgroup))
+       if (memcg->css.cgroup)
                return true;
 #endif
        return false;
@@ -1098,7 +1098,12 @@ static unsigned long shrink_page_list(struct list_head *page_list,
                        if (!sc->may_writepage)
                                goto keep_locked;
 
-                       /* Page is dirty, try to write it out here */
+                       /*
+                        * Page is dirty. Flush the TLB if a writable entry
+                        * potentially exists to avoid CPU writes after IO
+                        * starts and then write it out here.
+                        */
+                       try_to_unmap_flush_dirty();
                        switch (pageout(page, mapping, sc)) {
                        case PAGE_KEEP:
                                goto keep_locked;
@@ -1191,7 +1196,7 @@ cull_mlocked:
                if (PageSwapCache(page))
                        try_to_free_swap(page);
                unlock_page(page);
-               putback_lru_page(page);
+               list_add(&page->lru, &ret_pages);
                continue;
 
 activate_locked:
@@ -1354,7 +1359,8 @@ static unsigned long isolate_lru_pages(unsigned long nr_to_scan,
        unsigned long nr_taken = 0;
        unsigned long scan;
 
-       for (scan = 0; scan < nr_to_scan && !list_empty(src); scan++) {
+       for (scan = 0; scan < nr_to_scan && nr_taken < nr_to_scan &&
+                                       !list_empty(src); scan++) {
                struct page *page;
                int nr_pages;