src/patches/suse-2.6.27.39/patches.arch/mm-avoid-bad-page-on-lru

   1 From: Russ Anderson <rja@sgi.com>
   2 Subject: mm: Avoid putting a bad page back on the LRU v8
   3 References: 415829
   4 Acked-by: schwab@suse.de
   5
   6 Prevent a page with a physical memory error from being placed back
   7 on the LRU.  A new page flag (PG_memerror) is added if
   8 CONFIG_PAGEFLAGS_EXTENDED is defined.
   9
  10 Version 8 change:  Removed hot path check for pages with memory
  11 errors on the free list.
  12
  13 Signed-off-by: Russ Anderson <rja@sgi.com>
  14 Reviewed-by: Christoph Lameter <cl@linux-foundation.org>
  15
  16 ---
  17  include/linux/page-flags.h |   15 ++++++++++++++-
  18  mm/migrate.c               |   36 +++++++++++++++++++++++++++++++++++-
  19  2 files changed, 49 insertions(+), 2 deletions(-)
  20
  21 Index: linux/mm/migrate.c
  22 ===================================================================
  23 --- linux.orig/mm/migrate.c     2008-07-29 13:18:23.000000000 -0500
  24 +++ linux/mm/migrate.c  2008-07-29 13:21:03.000000000 -0500
  25 @@ -65,6 +65,7 @@ int isolate_lru_page(struct page *page,
  26         }
  27         return ret;
  28  }
  29 +EXPORT_SYMBOL(isolate_lru_page);
  30
  31  /*
  32   * migrate_prep() needs to be called before we start compiling a list of pages
  33 @@ -82,6 +83,7 @@ int migrate_prep(void)
  34
  35         return 0;
  36  }
  37 +EXPORT_SYMBOL(migrate_prep);
  38
  39  static inline void move_to_lru(struct page *page)
  40  {
  41 @@ -116,6 +118,7 @@ int putback_lru_pages(struct list_head *
  42         }
  43         return count;
  44  }
  45 +EXPORT_SYMBOL(putback_lru_pages);
  46
  47  /*
  48   * Restore a potential migration pte to a working pte entry
  49 @@ -741,7 +744,26 @@ unlock:
  50                  * restored.
  51                  */
  52                 list_del(&page->lru);
  53 -               move_to_lru(page);
  54 +               if (PageMemError(page)) {
  55 +                       if (rc == 0)
  56 +                               /*
  57 +                                * A page with a memory error that has
  58 +                                * been migrated will not be moved to
  59 +                                * the LRU.
  60 +                                */
  61 +                               goto move_newpage;
  62 +                       else
  63 +                               /*
  64 +                                * The page failed to migrate and will not
  65 +                                * be added to the bad page list.  Clearing
  66 +                                * the error bit will allow another attempt
  67 +                                * to migrate if it gets another correctable
  68 +                                * error.
  69 +                                */
  70 +                               ClearPageMemError(page);
  71 +               }
  72 +
  73 +               move_to_lru(page);
  74         }
  75
  76  move_newpage:
  77 @@ -813,6 +835,17 @@ int migrate_pages(struct list_head *from
  78                         }
  79                 }
  80         }
  81 +
  82 +       if (rc != 0)
  83 +               list_for_each_entry_safe(page, page2, from, lru)
  84 +                       if (PageMemError(page))
  85 +                               /*
  86 +                                * The page failed to migrate.  Clearing
  87 +                                * the error bit will allow another attempt
  88 +                                * to migrate if it gets another correctable
  89 +                                * error.
  90 +                                */
  91 +                               ClearPageMemError(page);
  92         rc = 0;
  93  out:
  94         if (!swapwrite)
  95 @@ -825,6 +858,7 @@ out:
  96
  97         return nr_failed + retry;
  98  }
  99 +EXPORT_SYMBOL(migrate_pages);
 100
 101  #ifdef CONFIG_NUMA
 102  /*
 103 Index: linux/include/linux/page-flags.h
 104 ===================================================================
 105 --- linux.orig/include/linux/page-flags.h       2008-07-29 13:18:23.000000000 -0500
 106 +++ linux/include/linux/page-flags.h    2008-07-29 13:21:03.000000000 -0500
 107 @@ -84,6 +84,7 @@ enum pageflags {
 108         PG_private,             /* If pagecache, has fs-private data */
 109         PG_writeback,           /* Page is under writeback */
 110  #ifdef CONFIG_PAGEFLAGS_EXTENDED
 111 +       PG_memerror,            /* Page has a physical memory error */
 112         PG_head,                /* A head page */
 113         PG_tail,                /* A tail page */
 114  #else
 115 @@ -147,15 +148,21 @@ static inline int TestSetPage##uname(str
 116  static inline int TestClearPage##uname(struct page *page)              \
 117                 { return test_and_clear_bit(PG_##lname, &page->flags); }
 118
 119 +#define PAGEFLAGMASK(uname, lname)                                     \
 120 +static inline int PAGEMASK_##uname(void)                               \
 121 +               { return (1 << PG_##lname); }
 122
 123  #define PAGEFLAG(uname, lname) TESTPAGEFLAG(uname, lname)              \
 124 -       SETPAGEFLAG(uname, lname) CLEARPAGEFLAG(uname, lname)
 125 +       SETPAGEFLAG(uname, lname) CLEARPAGEFLAG(uname, lname)           \
 126 +       PAGEFLAGMASK(uname, lname)
 127
 128  #define __PAGEFLAG(uname, lname) TESTPAGEFLAG(uname, lname)            \
 129         __SETPAGEFLAG(uname, lname)  __CLEARPAGEFLAG(uname, lname)
 130
 131  #define PAGEFLAG_FALSE(uname)                                          \
 132  static inline int Page##uname(struct page *page)                       \
 133 +                       { return 0; }                                   \
 134 +static inline int PAGEMASK_##uname(void)                               \
 135                         { return 0; }
 136
 137  #define TESTSCFLAG(uname, lname)                                       \
 138 @@ -325,6 +332,12 @@ static inline void __ClearPageTail(struc
 139  }
 140
 141  #endif /* !PAGEFLAGS_EXTENDED */
 142 +
 143 +#ifdef CONFIG_PAGEFLAGS_EXTENDED
 144 +PAGEFLAG(MemError, memerror)
 145 +#else
 146 +PAGEFLAG_FALSE(MemError)
 147 +#endif
 148
 149  #define PAGE_FLAGS     (1 << PG_lru   | 1 << PG_private   | 1 << PG_locked | \
 150                          1 << PG_buddy | 1 << PG_writeback | \