mm: show page state on migration failure

It is very useful to find the reason of the migration failure if we
know what the page is not migrated and the state of the page.

Change-Id: If6def51cbe8ac5b48a49c860a925633a36b498a2
Signed-off-by: Cho KyongHo <pullip.cho@samsung.com>

diff --git a/mm/migrate.c b/mm/migrate.c
index 1236449b4777be3cf61e8cd68616c2c3faa5fd9f..104b9746942d6d48e049cb7952f6c528691cef68 100644 (file)
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -1406,6 +1406,16 @@ int migrate_pages(struct list_head *from, new_page_t get_new_page,
                                                private, page, pass > 2, mode,
                                                reason);
 
+                       if ((rc != -EAGAIN) && (rc != MIGRATEPAGE_SUCCESS)) {
+                               phys_addr_t pa = page_to_phys(page);
+
+                               pr_err("%s failed(%d): PA%pa,mapcnt%d,cnt%d\n",
+                                       __func__, rc, &pa,
+                                       page_mapcount(page), page_count(page));
+
+                               dump_page_owner(page);
+                       }
+
                        switch(rc) {
                        case -ENOMEM:
                                nr_failed++;