mm: compaction: fix COMPACTPAGEFAILED counting

Presently update_nr_listpages() doesn't have a role.  That's because lists
passed is always empty just after calling migrate_pages.  The
migrate_pages cleans up page list which have failed to migrate before
returning by aaa994b3.

 [PATCH] page migration: handle freeing of pages in migrate_pages()

 Do not leave pages on the lists passed to migrate_pages().  Seems that we will
 not need any postprocessing of pages.  This will simplify the handling of
 pages by the callers of migrate_pages().

At that time, we thought we don't need any postprocessing of pages.  But
the situation is changed.  The compaction need to know the number of
failed to migrate for COMPACTPAGEFAILED stat

This patch makes new rule for caller of migrate_pages to call
putback_lru_pages.  So caller need to clean up the lists so it has a
chance to postprocess the pages.  [suggested by Christoph Lameter]

Signed-off-by: Minchan Kim <minchan.kim@gmail.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Andi Kleen <andi@firstfloor.org>
Reviewed-by: Mel Gorman <mel@csn.ul.ie>
Reviewed-by: Wu Fengguang <fengguang.wu@intel.com>
Acked-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/mm/memory-failure.c b/mm/memory-failure.c
index 44a8cefeae6eb9627bf8f81330ea4edaa2452d81..124324134ff67b3c4a0bc06661b4f70f2406840f 100644 (file)
--- a/mm/memory-failure.c
+++ b/mm/memory-failure.c
@@ -1292,6 +1292,7 @@ static int soft_offline_huge_page(struct page *page, int flags)
        list_add(&hpage->lru, &pagelist);
        ret = migrate_huge_pages(&pagelist, new_page, MPOL_MF_MOVE_ALL, 0);
        if (ret) {
+                       putback_lru_pages(&pagelist);
                pr_debug("soft offline: %#lx: migration failed %d, type %lx\n",
                         pfn, ret, page->flags);
                if (ret > 0)

diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index 06662c5a3e86a1fc8f2db231e038d3e888d68801..4821338b4e4b02c8293a3fae50182d87a23667b4 100644 (file)
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -731,6 +731,8 @@ do_migrate_range(unsigned long start_pfn, unsigned long end_pfn)
                goto out;
        /* this function returns # of failed pages */
        ret = migrate_pages(&source, hotremove_migrate_alloc, 0, 1);
+       if (ret)
+               putback_lru_pages(&source);
 
 out:
        return ret;

diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index f969da5dd8a2136b92aab7e7c1a6ecc9083d6cb9..21243b2b7b070827809e443331be43a7172706d8 100644 (file)
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -931,8 +931,11 @@ static int migrate_to_node(struct mm_struct *mm, int source, int dest,
        check_range(mm, mm->mmap->vm_start, mm->task_size, &nmask,
                        flags | MPOL_MF_DISCONTIG_OK, &pagelist);
 
-       if (!list_empty(&pagelist))
+       if (!list_empty(&pagelist)) {
                err = migrate_pages(&pagelist, new_node_page, dest, 0);
+               if (err)
+                       putback_lru_pages(&pagelist);
+       }
 
        return err;
 }
@@ -1147,9 +1150,12 @@ static long do_mbind(unsigned long start, unsigned long len,
 
                err = mbind_range(mm, start, end, new);
 
-               if (!list_empty(&pagelist))
+               if (!list_empty(&pagelist)) {
                        nr_failed = migrate_pages(&pagelist, new_vma_page,
                                                (unsigned long)vma, 0);
+                       if (nr_failed)
+                               putback_lru_pages(&pagelist);
+               }
 
                if (!err && nr_failed && (flags & MPOL_MF_STRICT))
                        err = -EIO;

diff --git a/mm/migrate.c b/mm/migrate.c
index d917ac3207f51b9f4c4ec2927f31db82159fc193..35e454189966cbe42eab5e2172c7d64746d864c8 100644 (file)
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -883,8 +883,9 @@ out:
  *
  * The function returns after 10 attempts or if no pages
  * are movable anymore because to has become empty
- * or no retryable pages exist anymore. All pages will be
- * returned to the LRU or freed.
+ * or no retryable pages exist anymore.
+ * Caller should call putback_lru_pages to return pages to the LRU
+ * or free list.
  *
  * Return: Number of pages not migrated or error code.
  */
@@ -931,8 +932,6 @@ out:
        if (!swapwrite)
                current->flags &= ~PF_SWAPWRITE;
 
-       putback_lru_pages(from);
-
        if (rc)
                return rc;
 
@@ -1087,9 +1086,12 @@ set_status:
        }
 
        err = 0;
-       if (!list_empty(&pagelist))
+       if (!list_empty(&pagelist)) {
                err = migrate_pages(&pagelist, new_page_node,
                                (unsigned long)pm, 0);
+               if (err)
+                       putback_lru_pages(&pagelist);
+       }
 
        up_read(&mm->mmap_sem);
        return err;