]> asedeno.scripts.mit.edu Git - linux.git/blobdiff - mm/migrate.c
mm: enable thp migration for shmem thp
[linux.git] / mm / migrate.c
index 70ef794cccae97feda86c34e54b961eaa120138e..568433023831ae098dd5a9d3c1dd209d7dd04be7 100644 (file)
@@ -472,7 +472,7 @@ int migrate_page_move_mapping(struct address_space *mapping,
        pslot = radix_tree_lookup_slot(&mapping->i_pages,
                                        page_index(page));
 
-       expected_count += 1 + page_has_private(page);
+       expected_count += hpage_nr_pages(page) + page_has_private(page);
        if (page_count(page) != expected_count ||
                radix_tree_deref_slot_protected(pslot,
                                        &mapping->i_pages.xa_lock) != page) {
@@ -505,7 +505,7 @@ int migrate_page_move_mapping(struct address_space *mapping,
         */
        newpage->index = page->index;
        newpage->mapping = page->mapping;
-       get_page(newpage);      /* add cache reference */
+       page_ref_add(newpage, hpage_nr_pages(page)); /* add cache reference */
        if (PageSwapBacked(page)) {
                __SetPageSwapBacked(newpage);
                if (PageSwapCache(page)) {
@@ -524,13 +524,26 @@ int migrate_page_move_mapping(struct address_space *mapping,
        }
 
        radix_tree_replace_slot(&mapping->i_pages, pslot, newpage);
+       if (PageTransHuge(page)) {
+               int i;
+               int index = page_index(page);
+
+               for (i = 0; i < HPAGE_PMD_NR; i++) {
+                       pslot = radix_tree_lookup_slot(&mapping->i_pages,
+                                                      index + i);
+                       radix_tree_replace_slot(&mapping->i_pages, pslot,
+                                               newpage + i);
+               }
+       } else {
+               radix_tree_replace_slot(&mapping->i_pages, pslot, newpage);
+       }
 
        /*
         * Drop cache reference from old page by unfreezing
         * to one less reference.
         * We know this isn't the last reference.
         */
-       page_ref_unfreeze(page, expected_count - 1);
+       page_ref_unfreeze(page, expected_count - hpage_nr_pages(page));
 
        xa_unlock(&mapping->i_pages);
        /* Leave irq disabled to prevent preemption while updating stats */