1 files changed, 17 insertions, 45 deletions

diff --git a/block/blk-ioc.c b/block/blk-ioc.c
index fb23965595da..e23c797b4685 100644
--- a/block/blk-ioc.c
+++ b/block/blk-ioc.c
@@ -205,16 +205,15 @@ void exit_io_context(struct task_struct *task)
         put_io_context(ioc, NULL);
 }
 
-static struct io_context *create_task_io_context(struct task_struct *task,
-                                                 gfp_t gfp_flags, int node,
-                                                 bool take_ref)
+void create_io_context_slowpath(struct task_struct *task, gfp_t gfp_flags,
+                                int node)
 {
         struct io_context *ioc;
 
         ioc = kmem_cache_alloc_node(iocontext_cachep, gfp_flags | __GFP_ZERO,
                                     node);
         if (unlikely(!ioc))
-                return NULL;
+                return;
 
         /* initialize */
         atomic_long_set(&ioc->refcount, 1);
@@ -226,42 +225,13 @@ static struct io_context *create_task_io_context(struct task_struct *task,
 
         /* try to install, somebody might already have beaten us to it */
         task_lock(task);
-
-        if (!task->io_context && !(task->flags & PF_EXITING)) {
+        if (!task->io_context && !(task->flags & PF_EXITING))
                 task->io_context = ioc;
-        } else {
+        else
                 kmem_cache_free(iocontext_cachep, ioc);
-                ioc = task->io_context;
-        }
-
-        if (ioc && take_ref)
-                get_io_context(ioc);
-
         task_unlock(task);
-        return ioc;
 }
-
-/**
- * current_io_context - get io_context of %current
- * @gfp_flags: allocation flags, used if allocation is necessary
- * @node: allocation node, used if allocation is necessary
- *
- * Return io_context of %current.  If it doesn't exist, it is created with
- * @gfp_flags and @node.  The returned io_context does NOT have its
- * reference count incremented.  Because io_context is exited only on task
- * exit, %current can be sure that the returned io_context is valid and
- * alive as long as it is executing.
- */
-struct io_context *current_io_context(gfp_t gfp_flags, int node)
-{
-        might_sleep_if(gfp_flags & __GFP_WAIT);
-
-        if (current->io_context)
-                return current->io_context;
-
-        return create_task_io_context(current, gfp_flags, node, false);
-}
-EXPORT_SYMBOL(current_io_context);
+EXPORT_SYMBOL(create_io_context_slowpath);
 
 /**
  * get_task_io_context - get io_context of a task
@@ -274,7 +244,7 @@ EXPORT_SYMBOL(current_io_context);
  * incremented.
  *
  * This function always goes through task_lock() and it's better to use
- * current_io_context() + get_io_context() for %current.
+ * %current->io_context + get_io_context() for %current.
  */
 struct io_context *get_task_io_context(struct task_struct *task,
                                        gfp_t gfp_flags, int node)
@@ -283,16 +253,18 @@ struct io_context *get_task_io_context(struct task_struct *task,
 
         might_sleep_if(gfp_flags & __GFP_WAIT);
 
-        task_lock(task);
-        ioc = task->io_context;
-        if (likely(ioc)) {
-                get_io_context(ioc);
+        do {
+                task_lock(task);
+                ioc = task->io_context;
+                if (likely(ioc)) {
+                        get_io_context(ioc);
+                        task_unlock(task);
+                        return ioc;
+                }
                 task_unlock(task);
-                return ioc;
-        }
-        task_unlock(task);
+        } while (create_io_context(task, gfp_flags, node));
 
-        return create_task_io_context(task, gfp_flags, node, true);
+        return NULL;
 }
 EXPORT_SYMBOL(get_task_io_context);