vcs.maemo.org Git - kernel-bfs/blob - kernel-bfs-2.6.28/debian/patches/bfq/block-switch-from-BFQ-v1-to-BFQ-v1-r1.patch

   1 diff -uprN linux-2.6.28.orig/block/bfq-ioc.c linux-2.6.28.new/block/bfq-ioc.c
   2 --- linux-2.6.28.orig/block/bfq-ioc.c   2011-06-11 08:27:30.326116630 +0200
   3 +++ linux-2.6.28.new/block/bfq-ioc.c    2011-06-11 08:57:12.535863444 +0200
   4 @@ -55,10 +55,11 @@ static void cic_free_func(struct io_cont
   5  {
   6         unsigned long flags;
   7
   8 -       BUG_ON(cic->dead_key == 0);
   9 +       BUG_ON(!(cic->dead_key & CIC_DEAD_KEY));
  10
  11         spin_lock_irqsave(&ioc->lock, flags);
  12 -       radix_tree_delete(&ioc->bfq_radix_root, cic->dead_key);
  13 +       radix_tree_delete(&ioc->bfq_radix_root,
  14 +               cic->dead_key >> CIC_DEAD_INDEX_SHIFT);
  15         hlist_del_init_rcu(&cic->cic_list);
  16         spin_unlock_irqrestore(&ioc->lock, flags);
  17
  18 @@ -83,9 +84,7 @@ static void bfq_free_io_context(struct i
  19   *
  20   * Whenever no more tasks are using @cic or @bfqd is deallocated we
  21   * need to invalidate its entry in the radix tree hash table and to
  22 - * release the queues it refers to.  Save the key used for insertion
  23 - * in @cic->dead_key to remove @cic from the radix tree later and assign
  24 - * %NULL to its search key to prevent future lookups to succeed on it.
  25 + * release the queues it refers to.
  26   *
  27   * Called under the queue lock.
  28   */
  29 @@ -99,7 +98,7 @@ static void __bfq_exit_single_io_context
  30         /*
  31          * Make sure key == NULL is seen for dead queues.
  32          */
  33 -       cic->dead_key = (unsigned long)cic->key;
  34 +       cic->dead_key = bfqd_dead_key(bfqd);
  35         smp_wmb();
  36
  37         rcu_assign_pointer(cic->key, NULL);
  38 @@ -190,6 +189,7 @@ static void bfq_drop_dead_cic(struct bfq
  39         unsigned long flags;
  40
  41         WARN_ON(!list_empty(&cic->queue_list));
  42 +       BUG_ON(cic->dead_key != bfqd_dead_key(bfqd));
  43
  44         spin_lock_irqsave(&ioc->lock, flags);
  45
  46 @@ -203,7 +203,7 @@ static void bfq_drop_dead_cic(struct bfq
  47          * times.
  48          */
  49         if (!hlist_unhashed(&cic->cic_list)) {
  50 -               radix_tree_delete(&ioc->bfq_radix_root, (unsigned long)bfqd);
  51 +               radix_tree_delete(&ioc->bfq_radix_root, bfqd->cic_index);
  52                 hlist_del_init_rcu(&cic->cic_list);
  53                 bfq_cic_free(cic);
  54         }
  55 @@ -241,7 +241,7 @@ static struct cfq_io_context *bfq_cic_lo
  56
  57         do {
  58                 cic = radix_tree_lookup(&ioc->bfq_radix_root,
  59 -                                       (unsigned long)bfqd);
  60 +                                       bfqd->cic_index);
  61                 if (cic == NULL)
  62                         goto out;
  63
  64 @@ -292,7 +292,7 @@ static int bfq_cic_link(struct bfq_data
  65
  66                 spin_lock_irqsave(&ioc->lock, flags);
  67                 ret = radix_tree_insert(&ioc->bfq_radix_root,
  68 -                                       (unsigned long)bfqd, cic);
  69 +                                       bfqd->cic_index, cic);
  70                 if (ret == 0)
  71                         hlist_add_head_rcu(&cic->cic_list, &ioc->bfq_cic_list);
  72                 spin_unlock_irqrestore(&ioc->lock, flags);
  73 diff -uprN linux-2.6.28.orig/block/bfq-iosched.c linux-2.6.28.new/block/bfq-iosched.c
  74 --- linux-2.6.28.orig/block/bfq-iosched.c       2011-06-11 08:57:33.541762649 +0200
  75 +++ linux-2.6.28.new/block/bfq-iosched.c        2011-06-11 08:57:12.543862653 +0200
  76 @@ -59,6 +59,7 @@
  77  #include <linux/elevator.h>
  78  #include <linux/rbtree.h>
  79  #include <linux/ioprio.h>
  80 +#include <linux/idr.h>
  81  #include "bfq.h"
  82
  83  /* Max number of dispatches in one round of service. */
  84 @@ -98,6 +99,9 @@ static DEFINE_PER_CPU(unsigned long, bfq
  85  static struct completion *bfq_ioc_gone;
  86  static DEFINE_SPINLOCK(bfq_ioc_gone_lock);
  87
  88 +static DEFINE_SPINLOCK(cic_index_lock);
  89 +static DEFINE_IDA(cic_index_ida);
  90 +
  91  /* Below this threshold (in ms), we consider thinktime immediate. */
  92  #define BFQ_MIN_TT             2
  93
  94 @@ -1983,6 +1987,10 @@ static void bfq_exit_queue(struct elevat
  95
  96         bfq_shutdown_timer_wq(bfqd);
  97
  98 +       spin_lock(&cic_index_lock);
  99 +       ida_remove(&cic_index_ida, bfqd->cic_index);
 100 +       spin_unlock(&cic_index_lock);
 101 +
 102         /* Wait for cic->key accessors to exit their grace periods. */
 103         synchronize_rcu();
 104
 105 @@ -1992,15 +2000,40 @@ static void bfq_exit_queue(struct elevat
 106         kfree(bfqd);
 107  }
 108
 109 +static int bfq_alloc_cic_index(void)
 110 +{
 111 +       int index, error;
 112 +
 113 +       do {
 114 +               if (!ida_pre_get(&cic_index_ida, GFP_KERNEL))
 115 +                       return -ENOMEM;
 116 +
 117 +               spin_lock(&cic_index_lock);
 118 +               error = ida_get_new(&cic_index_ida, &index);
 119 +               spin_unlock(&cic_index_lock);
 120 +               if (error && error != -EAGAIN)
 121 +                       return error;
 122 +       } while (error);
 123 +
 124 +       return index;
 125 +}
 126 +
 127  static void *bfq_init_queue(struct request_queue *q)
 128  {
 129         struct bfq_group *bfqg;
 130         struct bfq_data *bfqd;
 131 +       int i;
 132 +
 133 +       i = bfq_alloc_cic_index();
 134 +       if (i < 0)
 135 +               return NULL;
 136
 137         bfqd = kmalloc_node(sizeof(*bfqd), GFP_KERNEL | __GFP_ZERO, q->node);
 138         if (bfqd == NULL)
 139                 return NULL;
 140
 141 +       bfqd->cic_index = i;
 142 +
 143         INIT_LIST_HEAD(&bfqd->cic_list);
 144
 145         bfqd->queue = q;
 146 @@ -2273,6 +2306,7 @@ static void __exit bfq_exit(void)
 147         smp_wmb();
 148         if (elv_ioc_count_read(bfq_ioc_count) != 0)
 149                 wait_for_completion(&all_gone);
 150 +       ida_destroy(&cic_index_ida);
 151         bfq_slab_kill();
 152  }
 153
 154 diff -uprN linux-2.6.28.orig/block/bfq.h linux-2.6.28.new/block/bfq.h
 155 --- linux-2.6.28.orig/block/bfq.h       2011-06-11 08:57:33.545762247 +0200
 156 +++ linux-2.6.28.new/block/bfq.h        2011-06-11 08:57:12.543862653 +0200
 157 @@ -195,6 +195,7 @@ struct bfq_group;
 158   * @peak_rate: peak transfer rate observed for a budget.
 159   * @peak_rate_samples: number of samples used to calculate @peak_rate.
 160   * @bfq_max_budget: maximum budget allotted to a bfq_queue before rescheduling.
 161 + * @cic_index: use small consequent indexes as radix tree keys to reduce depth
 162   * @cic_list: list of all the cics active on the bfq_data device.
 163   * @group_list: list of all the bfq_groups active on the device.
 164   * @active_list: list of all the bfq_queues active on the device.
 165 @@ -248,6 +249,7 @@ struct bfq_data {
 166         u64 peak_rate;
 167         unsigned long bfq_max_budget;
 168
 169 +       unsigned int cic_index;
 170         struct list_head cic_list;
 171         struct hlist_head group_list;
 172         struct list_head active_list;
 173 @@ -495,6 +497,14 @@ static inline void call_for_each_cic(str
 174         rcu_read_unlock();
 175  }
 176
 177 +#define CIC_DEAD_KEY    1ul
 178 +#define CIC_DEAD_INDEX_SHIFT    1
 179 +
 180 +static inline unsigned long bfqd_dead_key(struct bfq_data *bfqd)
 181 +{
 182 +       return (unsigned long)(bfqd->cic_index << CIC_DEAD_INDEX_SHIFT | CIC_DEAD_KEY);
 183 +}
 184 +
 185  /**
 186   * bfq_get_bfqd_locked - get a lock to a bfqd using a RCU protected pointer.
 187   * @ptr: a pointer to a bfqd.