percpu-refcount, aio: use percpu_ref_cancel_init() in ioctx_alloc()
percpu-refcount, aio: use percpu_ref_cancel_init() in ioctx_alloc()

ioctx_alloc() reaches inside percpu_ref and directly frees
->pcpu_count in its failure path, which is quite gross.  percpu_ref
has been providing a proper interface to do this,
percpu_ref_cancel_init(), for quite some time now.  Let's use that
instead.

This patch doesn't introduce any behavior changes.

Signed-off-by: Tejun Heo <546b05909706652891a87f7bfe385ae147f61f91@kernel.org>
Acked-by: Benjamin LaHaise <b05c66fa21e46731bb89a779db663748f3df8f6a@kvack.org>
Cc: Kent Overstreet <99dffa8a9668ab7f6cde1c94b42a210109971113@daterainc.com>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs