[PATCHSET block/for-4.2/writeback] blkcg: blkcg_policy methods cleanup

[Tejun Heo <tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>]

This patchset contains assorted cleanups for blkcg_policy methods.

* alloc/free are added.  exit is dropped.

* blk-throttle's async percpu allocation is replaced with direct
  allocation.

* all methods now take blkcg_policy_data instead of blkcg_gq.

Nothing too controversial.

Jens, as we're at the beginning of the 4.2 merge window, I'll ping /
repost this patchset along with other pending patchsets once -rc1
drops.

This patchset contains the following seven patches.

 0001-blkcg-remove-unnecessary-request_list-blkg-NULL-test.patch
 0002-blkcg-use-blkg_free-in-blkcg_init_queue-failure-path.patch
 0003-blkcg-make-blkcg_activate_policy-allow-NULL-pd_init_.patch
 0004-blkcg-replace-blkcg_policy-pd_size-with-pd_alloc-fre.patch
 0005-blk-throttle-remove-asynchrnous-percpu-stats-allocat.patch
 0006-blk-throttle-clean-up-blkg_policy_data-alloc-init-ex.patch
 0007-blkcg-make-blkcg_policy-methods-take-a-pointer-to-bl.patch

0001-0003 are misc cleanups.  0004-0006 add alloc/free methods and
remove blk-throttle's async percpu allocation mechanism.  0007 makes
all methods take blkcg_policy_data.

This patchset is also available in the following git branch.

 git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup.git review-blkcg-methods-cleanup

and is on top of

[1] block/for-4.2/writeback
[2] [PATCHSET block/for-4.2/writeback] block, cgroup: make cfq charge async IOs to the appropriate blkcgs

diffstat follows.  Thanks.

 block/blk-cgroup.c         |   53 +++++--------
 block/blk-throttle.c       |  173 +++++++++++++--------------------------------
 block/cfq-iosched.c        |   37 +++++++--
 include/linux/blk-cgroup.h |   31 +++-----
 4 files changed, 116 insertions(+), 178 deletions(-)

--
tejun

[1] 5857cd637bc0 ("bdi: fix wrong error return value in cgwb_create()").
[2] http://lkml.kernel.org/g/1433753973-23684-1-git-send-email-tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org