lustre/kernel_patches/patches/raid6-configurable-cachesize.patch

   1 --- linux-2.6.9.orig/drivers/md/raid6main.c     2006-09-07 23:10:43.000000000 +0800
   2 +++ linux-2.6.9/drivers/md/raid6main.c  2006-09-07 23:11:25.000000000 +0800
   3 @@ -33,7 +33,7 @@
   4   * Stripe cache
   5   */
   6
   7 -#define NR_STRIPES             256
   8 +static int raid6_nr_stripes = 256 * 8;
   9  #define STRIPE_SIZE            PAGE_SIZE
  10  #define STRIPE_SHIFT           (PAGE_SHIFT - 9)
  11  #define STRIPE_SECTORS         (STRIPE_SIZE>>9)
  12 @@ -111,7 +111,7 @@ static inline void __release_stripe(raid
  13                         list_add_tail(&sh->lru, &conf->inactive_list);
  14                         atomic_dec(&conf->active_stripes);
  15                         if (!conf->inactive_blocked ||
  16 -                           atomic_read(&conf->active_stripes) < (NR_STRIPES*3/4))
  17 +                           atomic_read(&conf->active_stripes) < (raid6_nr_stripes*3/4))
  18                                 wake_up(&conf->wait_for_stripe);
  19                 }
  20         }
  21 @@ -274,7 +274,7 @@ static struct stripe_head *get_active_st
  22                                 conf->inactive_blocked = 1;
  23                                 wait_event_lock_irq(conf->wait_for_stripe,
  24                                                     !list_empty(&conf->inactive_list) &&
  25 -                                                   (atomic_read(&conf->active_stripes) < (NR_STRIPES *3/4)
  26 +                                                   (atomic_read(&conf->active_stripes) < (raid6_nr_stripes *3/4)
  27                                                      || !conf->inactive_blocked),
  28                                                     conf->device_lock,
  29                                                     unplug_slaves(conf->mddev);
  30 @@ -1805,7 +1805,7 @@ static int run (mddev_t *mddev)
  31         conf->chunk_size = mddev->chunk_size;
  32         conf->level = mddev->level;
  33         conf->algorithm = mddev->layout;
  34 -       conf->max_nr_stripes = NR_STRIPES;
  35 +       conf->max_nr_stripes = raid6_nr_stripes;
  36
  37         /* device size must be a multiple of chunk size */
  38         mddev->size &= ~(mddev->chunk_size/1024 -1);
  39 @@ -2139,5 +2139,6 @@ static void raid6_exit (void)
  40
  41  module_init(raid6_init);
  42  module_exit(raid6_exit);
  43 +module_param(raid6_nr_stripes, int, 0644);
  44  MODULE_LICENSE("GPL");
  45  MODULE_ALIAS("md-personality-8"); /* RAID6 */