virtio_test: support event index
[linux-2.6.git] / block / blk-ioc.c
index 4ae0929..c898049 100644 (file)
@@ -7,6 +7,7 @@
 #include <linux/bio.h>
 #include <linux/blkdev.h>
 #include <linux/bootmem.h>     /* for max_pfn/max_low_pfn */
+#include <linux/slab.h>
 
 #include "blk.h"
 
@@ -17,17 +18,13 @@ static struct kmem_cache *iocontext_cachep;
 
 static void cfq_dtor(struct io_context *ioc)
 {
-       struct cfq_io_context *cic[1];
-       int r;
+       if (!hlist_empty(&ioc->cic_list)) {
+               struct cfq_io_context *cic;
 
-       /*
-        * We don't have a specific key to lookup with, so use the gang
-        * lookup to just retrieve the first item stored. The cfq exit
-        * function will iterate the full tree, so any member will do.
-        */
-       r = radix_tree_gang_lookup(&ioc->radix_root, (void **) cic, 0, 1);
-       if (r > 0)
-               cic[0]->dtor(ioc);
+               cic = list_entry(ioc->cic_list.first, struct cfq_io_context,
+                                                               cic_list);
+               cic->dtor(ioc);
+       }
 }
 
 /*
@@ -39,14 +36,12 @@ int put_io_context(struct io_context *ioc)
        if (ioc == NULL)
                return 1;
 
-       BUG_ON(atomic_read(&ioc->refcount) == 0);
+       BUG_ON(atomic_long_read(&ioc->refcount) == 0);
 
-       if (atomic_dec_and_test(&ioc->refcount)) {
+       if (atomic_long_dec_and_test(&ioc->refcount)) {
                rcu_read_lock();
-               if (ioc->aic && ioc->aic->dtor)
-                       ioc->aic->dtor(ioc->aic);
-               rcu_read_unlock();
                cfq_dtor(ioc);
+               rcu_read_unlock();
 
                kmem_cache_free(iocontext_cachep, ioc);
                return 1;
@@ -57,37 +52,32 @@ EXPORT_SYMBOL(put_io_context);
 
 static void cfq_exit(struct io_context *ioc)
 {
-       struct cfq_io_context *cic[1];
-       int r;
-
        rcu_read_lock();
-       /*
-        * See comment for cfq_dtor()
-        */
-       r = radix_tree_gang_lookup(&ioc->radix_root, (void **) cic, 0, 1);
-       rcu_read_unlock();
 
-       if (r > 0)
-               cic[0]->exit(ioc);
+       if (!hlist_empty(&ioc->cic_list)) {
+               struct cfq_io_context *cic;
+
+               cic = list_entry(ioc->cic_list.first, struct cfq_io_context,
+                                                               cic_list);
+               cic->exit(ioc);
+       }
+       rcu_read_unlock();
 }
 
-/* Called by the exitting task */
-void exit_io_context(void)
+/* Called by the exiting task */
+void exit_io_context(struct task_struct *task)
 {
        struct io_context *ioc;
 
-       task_lock(current);
-       ioc = current->io_context;
-       current->io_context = NULL;
-       task_unlock(current);
+       task_lock(task);
+       ioc = task->io_context;
+       task->io_context = NULL;
+       task_unlock(task);
 
-       if (atomic_dec_and_test(&ioc->nr_tasks)) {
-               if (ioc->aic && ioc->aic->exit)
-                       ioc->aic->exit(ioc->aic);
+       if (atomic_dec_and_test(&ioc->nr_tasks))
                cfq_exit(ioc);
 
-               put_io_context(ioc);
-       }
+       put_io_context(ioc);
 }
 
 struct io_context *alloc_io_context(gfp_t gfp_flags, int node)
@@ -96,16 +86,19 @@ struct io_context *alloc_io_context(gfp_t gfp_flags, int node)
 
        ret = kmem_cache_alloc_node(iocontext_cachep, gfp_flags, node);
        if (ret) {
-               atomic_set(&ret->refcount, 1);
+               atomic_long_set(&ret->refcount, 1);
                atomic_set(&ret->nr_tasks, 1);
                spin_lock_init(&ret->lock);
                ret->ioprio_changed = 0;
                ret->ioprio = 0;
-               ret->last_waited = jiffies; /* doesn't matter... */
+               ret->last_waited = 0; /* doesn't matter... */
                ret->nr_batch_requests = 0; /* because this is 0 */
-               ret->aic = NULL;
                INIT_RADIX_TREE(&ret->radix_root, GFP_ATOMIC | __GFP_HIGH);
+               INIT_HLIST_HEAD(&ret->cic_list);
                ret->ioc_data = NULL;
+#if defined(CONFIG_BLK_CGROUP) || defined(CONFIG_BLK_CGROUP_MODULE)
+               ret->cgroup_changed = 0;
+#endif
        }
 
        return ret;
@@ -156,26 +149,12 @@ struct io_context *get_io_context(gfp_t gfp_flags, int node)
                ret = current_io_context(gfp_flags, node);
                if (unlikely(!ret))
                        break;
-       } while (!atomic_inc_not_zero(&ret->refcount));
+       } while (!atomic_long_inc_not_zero(&ret->refcount));
 
        return ret;
 }
 EXPORT_SYMBOL(get_io_context);
 
-void copy_io_context(struct io_context **pdst, struct io_context **psrc)
-{
-       struct io_context *src = *psrc;
-       struct io_context *dst = *pdst;
-
-       if (src) {
-               BUG_ON(atomic_read(&src->refcount) == 0);
-               atomic_inc(&src->refcount);
-               put_io_context(dst);
-               *pdst = src;
-       }
-}
-EXPORT_SYMBOL(copy_io_context);
-
 static int __init blk_ioc_init(void)
 {
        iocontext_cachep = kmem_cache_create("blkdev_ioc",