mm: remove offlining arg to migrate_pages

No functional change, but the only purpose of the offlining argument to
migrate_pages() etc, was to ensure that __unmap_and_move() could migrate a
KSM page for memory hotremove (which took ksm_thread_mutex) but not for
other callers.  Now all cases are safe, remove the arg.

Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Petr Holasek <pholasek@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Izik Eidus <izik.eidus@ravellosystems.com>
Cc: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 13 insertions, 22 deletions

diff --git a/mm/migrate.c b/mm/migrate.c
index 20a03eb0667f..3bbaf5d230b0 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -701,7 +701,7 @@ static int move_to_new_page(struct page *newpage, struct page *page,
 }
 
 static int __unmap_and_move(struct page *page, struct page *newpage,
-                        int force, bool offlining, enum migrate_mode mode)
+                                int force, enum migrate_mode mode)
 {
         int rc = -EAGAIN;
         int remap_swapcache = 1;
@@ -847,8 +847,7 @@ out:
  * to the newly allocated page in newpage.
  */
 static int unmap_and_move(new_page_t get_new_page, unsigned long private,
-                        struct page *page, int force, bool offlining,
-                        enum migrate_mode mode)
+                        struct page *page, int force, enum migrate_mode mode)
 {
         int rc = 0;
         int *result = NULL;
@@ -866,7 +865,7 @@ static int unmap_and_move(new_page_t get_new_page, unsigned long private,
                 if (unlikely(split_huge_page(page)))
                         goto out;
 
-        rc = __unmap_and_move(page, newpage, force, offlining, mode);
+        rc = __unmap_and_move(page, newpage, force, mode);
 
         if (unlikely(rc == MIGRATEPAGE_BALLOON_SUCCESS)) {
                 /*
@@ -926,8 +925,7 @@ out:
  */
 static int unmap_and_move_huge_page(new_page_t get_new_page,
                                 unsigned long private, struct page *hpage,
-                                int force, bool offlining,
-                                enum migrate_mode mode)
+                                int force, enum migrate_mode mode)
 {
         int rc = 0;
         int *result = NULL;
@@ -989,9 +987,8 @@ out:
  *
  * Return: Number of pages not migrated or error code.
  */
-int migrate_pages(struct list_head *from,
-                new_page_t get_new_page, unsigned long private, bool offlining,
-                enum migrate_mode mode, int reason)
+int migrate_pages(struct list_head *from, new_page_t get_new_page,
+                unsigned long private, enum migrate_mode mode, int reason)
 {
         int retry = 1;
         int nr_failed = 0;
@@ -1012,8 +1009,7 @@ int migrate_pages(struct list_head *from,
                         cond_resched();
 
                         rc = unmap_and_move(get_new_page, private,
-                                                page, pass > 2, offlining,
-                                                mode);
+                                                page, pass > 2, mode);
 
                         switch(rc) {
                         case -ENOMEM:
@@ -1046,15 +1042,13 @@ out:
 }
 
 int migrate_huge_page(struct page *hpage, new_page_t get_new_page,
-                      unsigned long private, bool offlining,
-                      enum migrate_mode mode)
+                      unsigned long private, enum migrate_mode mode)
 {
         int pass, rc;
 
         for (pass = 0; pass < 10; pass++) {
-                rc = unmap_and_move_huge_page(get_new_page,
-                                              private, hpage, pass > 2, offlining,
-                                              mode);
+                rc = unmap_and_move_huge_page(get_new_page, private,
+                                                hpage, pass > 2, mode);
                 switch (rc) {
                 case -ENOMEM:
                         goto out;
@@ -1177,8 +1171,7 @@ set_status:
         err = 0;
         if (!list_empty(&pagelist)) {
                 err = migrate_pages(&pagelist, new_page_node,
-                                (unsigned long)pm, 0, MIGRATE_SYNC,
-                                MR_SYSCALL);
+                                (unsigned long)pm, MIGRATE_SYNC, MR_SYSCALL);
                 if (err)
                         putback_lru_pages(&pagelist);
         }
@@ -1613,10 +1606,8 @@ int migrate_misplaced_page(struct page *page, int node)
                 goto out;
 
         list_add(&page->lru, &migratepages);
-        nr_remaining = migrate_pages(&migratepages,
-                        alloc_misplaced_dst_page,
-                        node, false, MIGRATE_ASYNC,
-                        MR_NUMA_MISPLACED);
+        nr_remaining = migrate_pages(&migratepages, alloc_misplaced_dst_page,
+                                     node, MIGRATE_ASYNC, MR_NUMA_MISPLACED);
         if (nr_remaining) {
                 putback_lru_pages(&migratepages);
                 isolated = 0;