cfq-iosched: add hlist for browsing parallel to the radix tree

[safe/jmp/linux-2.6] / block / blk-ioc.c

diff --git a/block/blk-ioc.c b/block/blk-ioc.c
index 4ae0929..e34df7c 100644 (file)
--- a/block/blk-ioc.c
+++ b/block/blk-ioc.c
@@ -17,17 +17,13 @@ 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);
+       }
 }
 
 /*
@@ -57,18 +53,16 @@ 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 */
@@ -105,6 +99,7 @@ struct io_context *alloc_io_context(gfp_t gfp_flags, int node)
                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;
        }