blkcg: move blkio_group_stats_cpu and friends to blk-throttle.c

blkio_group_stats_cpu is used only by blk-throtl and has no reason to
be defined in blkcg core.

* Move blkio_group_stats_cpu to blk-throttle.c and rename it to
  tg_stats_cpu.

* blkg_policy_data->stats_cpu is replaced with throtl_grp->stats_cpu.
  prfill functions updated accordingly.

* All related macros / functions are renamed so that they have tg_
  prefix and the unnecessary @pol arguments are dropped.

* Per-cpu stats allocation code is also moved from blk-cgroup.c to
  blk-throttle.c and gets simplified to only deal with
  BLKIO_POLICY_THROTL.  percpu stat free is performed by the exit
  method throtl_exit_blkio_group().

* throtl_reset_group_stats() implemented for
  blkio_reset_group_stats_fn method so that tg->stats_cpu can be
  reset.

Signed-off-by: Tejun Heo <tj@kernel.org>

1 files changed, 0 insertions, 13 deletions

diff --git a/block/blk-cgroup.h b/block/blk-cgroup.h
index 791570394..e368dd00 100644
--- a/block/blk-cgroup.h
+++ b/block/blk-cgroup.h
@@ -64,14 +64,6 @@ struct blkg_rwstat {
 	uint64_t			cnt[BLKG_RWSTAT_NR];
 };
 
-/* Per cpu blkio group stats */
-struct blkio_group_stats_cpu {
-	/* total bytes transferred */
-	struct blkg_rwstat		service_bytes;
-	/* total IOs serviced, post merge */
-	struct blkg_rwstat		serviced;
-};
-
 struct blkio_group_conf {
 	unsigned int weight;
 	u64 iops[2];
@@ -86,9 +78,6 @@ struct blkg_policy_data {
 	/* Configuration */
 	struct blkio_group_conf conf;
 
-	/* Per cpu stats pointer */
-	struct blkio_group_stats_cpu __percpu *stats_cpu;
-
 	/* pol->pdata_size bytes of private data used by policy impl */
 	char pdata[] __aligned(__alignof__(unsigned long long));
 };
@@ -106,8 +95,6 @@ struct blkio_group {
 
 	struct blkg_policy_data *pd[BLKIO_NR_POLICIES];
 
-	/* List of blkg waiting for per cpu stats memory to be allocated */
-	struct list_head alloc_node;
 	struct rcu_head rcu_head;
 };