blkcg: move blkg_for_each_descendant_pre() to block/blk-cgroup.h
blk-throttle hierarchy support will make use of it. Move
blkg_for_each_descendant_pre() from block/blk-cgroup.c to
block/blk-cgroup.h.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c
index 7fc35f6..b950306 100644
--- a/block/blk-cgroup.c
+++ b/block/blk-cgroup.c
@@ -32,26 +32,6 @@
static struct blkcg_policy *blkcg_policy[BLKCG_MAX_POLS];
-static struct blkcg_gq *__blkg_lookup(struct blkcg *blkcg,
- struct request_queue *q, bool update_hint);
-
-/**
- * blkg_for_each_descendant_pre - pre-order walk of a blkg's descendants
- * @d_blkg: loop cursor pointing to the current descendant
- * @pos_cgrp: used for iteration
- * @p_blkg: target blkg to walk descendants of
- *
- * Walk @c_blkg through the descendants of @p_blkg. Must be used with RCU
- * read locked. If called under either blkcg or queue lock, the iteration
- * is guaranteed to include all and only online blkgs. The caller may
- * update @pos_cgrp by calling cgroup_rightmost_descendant() to skip
- * subtree.
- */
-#define blkg_for_each_descendant_pre(d_blkg, pos_cgrp, p_blkg) \
- cgroup_for_each_descendant_pre((pos_cgrp), (p_blkg)->blkcg->css.cgroup) \
- if (((d_blkg) = __blkg_lookup(cgroup_to_blkcg(pos_cgrp), \
- (p_blkg)->q, false)))
-
static bool blkcg_policy_enabled(struct request_queue *q,
const struct blkcg_policy *pol)
{
@@ -158,8 +138,8 @@
* @q's bypass state. If @update_hint is %true, the caller should be
* holding @q->queue_lock and lookup hint is updated on success.
*/
-static struct blkcg_gq *__blkg_lookup(struct blkcg *blkcg,
- struct request_queue *q, bool update_hint)
+struct blkcg_gq *__blkg_lookup(struct blkcg *blkcg, struct request_queue *q,
+ bool update_hint)
{
struct blkcg_gq *blkg;