3 files changed, 23 insertions, 22 deletions

diff --git a/drivers/block/as-iosched.c b/drivers/block/as-iosched.c
index 564172234819..c6744ff38294 100644
--- a/drivers/block/as-iosched.c
+++ b/drivers/block/as-iosched.c
@@ -1973,8 +1973,8 @@ static int __init as_init(void)
 
 static void __exit as_exit(void)
 {
-        kmem_cache_destroy(arq_pool);
         elv_unregister(&iosched_as);
+        kmem_cache_destroy(arq_pool);
 }
 
 module_init(as_init);
diff --git a/drivers/block/cfq-iosched.c b/drivers/block/cfq-iosched.c
index 94690e4d41e0..5281f8e70510 100644
--- a/drivers/block/cfq-iosched.c
+++ b/drivers/block/cfq-iosched.c
@@ -2418,28 +2418,8 @@ static int __init cfq_init(void)
 
 static void __exit cfq_exit(void)
 {
-        struct task_struct *g, *p;
-        unsigned long flags;
-
-        read_lock_irqsave(&tasklist_lock, flags);
-
-        /*
-         * iterate each process in the system, removing our io_context
-         */
-        do_each_thread(g, p) {
-                struct io_context *ioc = p->io_context;
-
-                if (ioc && ioc->cic) {
-                        ioc->cic->exit(ioc->cic);
-                        cfq_free_io_context(ioc->cic);
-                        ioc->cic = NULL;
-                }
-        } while_each_thread(g, p);
-
-        read_unlock_irqrestore(&tasklist_lock, flags);
-
-        cfq_slab_kill();
         elv_unregister(&iosched_cfq);
+        cfq_slab_kill();
 }
 
 module_init(cfq_init);
diff --git a/drivers/block/elevator.c b/drivers/block/elevator.c
index 55621d5c5774..58e881bfd189 100644
--- a/drivers/block/elevator.c
+++ b/drivers/block/elevator.c
@@ -642,6 +642,27 @@ EXPORT_SYMBOL_GPL(elv_register);
 
 void elv_unregister(struct elevator_type *e)
 {
+        struct task_struct *g, *p;
+
+        /*
+         * Iterate every thread in the process to remove the io contexts.
+         */
+        read_lock(&tasklist_lock);
+        do_each_thread(g, p) {
+                struct io_context *ioc = p->io_context;
+                if (ioc && ioc->cic) {
+                        ioc->cic->exit(ioc->cic);
+                        ioc->cic->dtor(ioc->cic);
+                        ioc->cic = NULL;
+                }
+                if (ioc && ioc->aic) {
+                        ioc->aic->exit(ioc->aic);
+                        ioc->aic->dtor(ioc->aic);
+                        ioc->aic = NULL;
+                }
+        } while_each_thread(g, p);
+        read_unlock(&tasklist_lock);
+
         spin_lock_irq(&elv_list_lock);
         list_del_init(&e->list);
         spin_unlock_irq(&elv_list_lock);