blk-cgroup: separate out blkg_rwstat under CONFIG_BLK_CGROUP_RWSTAT

blkg_rwstat is now only used by bfq-iosched and blk-throtl when on
cgroup1.  Let's move it into its own files and gate it behind a config
option.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

1 files changed, 0 insertions, 159 deletions

diff --git a/include/linux/blk-cgroup.h b/include/linux/blk-cgroup.h
index 867ab391e409..48a66738143d 100644
--- a/include/linux/blk-cgroup.h
+++ b/include/linux/blk-cgroup.h
@@ -41,17 +41,6 @@ enum blkg_iostat_type {
 	BLKG_IOSTAT_NR,
 };
 
-enum blkg_rwstat_type {
-	BLKG_RWSTAT_READ,
-	BLKG_RWSTAT_WRITE,
-	BLKG_RWSTAT_SYNC,
-	BLKG_RWSTAT_ASYNC,
-	BLKG_RWSTAT_DISCARD,
-
-	BLKG_RWSTAT_NR,
-	BLKG_RWSTAT_TOTAL = BLKG_RWSTAT_NR,
-};
-
 struct blkcg_gq;
 
 struct blkcg {
@@ -83,19 +72,6 @@ struct blkg_iostat_set {
 };
 
 /*
- * blkg_[rw]stat->aux_cnt is excluded for local stats but included for
- * recursive.  Used to carry stats of dead children.
- */
-struct blkg_rwstat {
-	struct percpu_counter		cpu_cnt[BLKG_RWSTAT_NR];
-	atomic64_t			aux_cnt[BLKG_RWSTAT_NR];
-};
-
-struct blkg_rwstat_sample {
-	u64				cnt[BLKG_RWSTAT_NR];
-};
-
-/*
  * A blkcg_gq (blkg) is association between a block cgroup (blkcg) and a
  * request_queue (q).  This is used by blkcg policies which need to track
  * information per blkcg - q pair.
@@ -223,13 +199,6 @@ int blkcg_activate_policy(struct request_queue *q,
 void blkcg_deactivate_policy(struct request_queue *q,
 			     const struct blkcg_policy *pol);
 
-static inline u64 blkg_rwstat_read_counter(struct blkg_rwstat *rwstat,
-		unsigned int idx)
-{
-	return atomic64_read(&rwstat->aux_cnt[idx]) +
-		percpu_counter_sum_positive(&rwstat->cpu_cnt[idx]);
-}
-
 const char *blkg_dev_name(struct blkcg_gq *blkg);
 void blkcg_print_blkgs(struct seq_file *sf, struct blkcg *blkcg,
 		       u64 (*prfill)(struct seq_file *,
@@ -237,12 +206,6 @@ void blkcg_print_blkgs(struct seq_file *sf, struct blkcg *blkcg,
 		       const struct blkcg_policy *pol, int data,
 		       bool show_total);
 u64 __blkg_prfill_u64(struct seq_file *sf, struct blkg_policy_data *pd, u64 v);
-u64 __blkg_prfill_rwstat(struct seq_file *sf, struct blkg_policy_data *pd,
-			 const struct blkg_rwstat_sample *rwstat);
-u64 blkg_prfill_rwstat(struct seq_file *sf, struct blkg_policy_data *pd,
-		       int off);
-void blkg_rwstat_recursive_sum(struct blkcg_gq *blkg, struct blkcg_policy *pol,
-		int off, struct blkg_rwstat_sample *sum);
 
 struct blkg_conf_ctx {
 	struct gendisk			*disk;
@@ -594,128 +557,6 @@ static inline void blkg_put(struct blkcg_gq *blkg)
 		if (((d_blkg) = __blkg_lookup(css_to_blkcg(pos_css),	\
 					      (p_blkg)->q, false)))
 
-static inline int blkg_rwstat_init(struct blkg_rwstat *rwstat, gfp_t gfp)
-{
-	int i, ret;
-
-	for (i = 0; i < BLKG_RWSTAT_NR; i++) {
-		ret = percpu_counter_init(&rwstat->cpu_cnt[i], 0, gfp);
-		if (ret) {
-			while (--i >= 0)
-				percpu_counter_destroy(&rwstat->cpu_cnt[i]);
-			return ret;
-		}
-		atomic64_set(&rwstat->aux_cnt[i], 0);
-	}
-	return 0;
-}
-
-static inline void blkg_rwstat_exit(struct blkg_rwstat *rwstat)
-{
-	int i;
-
-	for (i = 0; i < BLKG_RWSTAT_NR; i++)
-		percpu_counter_destroy(&rwstat->cpu_cnt[i]);
-}
-
-/**
- * blkg_rwstat_add - add a value to a blkg_rwstat
- * @rwstat: target blkg_rwstat
- * @op: REQ_OP and flags
- * @val: value to add
- *
- * Add @val to @rwstat.  The counters are chosen according to @rw.  The
- * caller is responsible for synchronizing calls to this function.
- */
-static inline void blkg_rwstat_add(struct blkg_rwstat *rwstat,
-				   unsigned int op, uint64_t val)
-{
-	struct percpu_counter *cnt;
-
-	if (op_is_discard(op))
-		cnt = &rwstat->cpu_cnt[BLKG_RWSTAT_DISCARD];
-	else if (op_is_write(op))
-		cnt = &rwstat->cpu_cnt[BLKG_RWSTAT_WRITE];
-	else
-		cnt = &rwstat->cpu_cnt[BLKG_RWSTAT_READ];
-
-	percpu_counter_add_batch(cnt, val, BLKG_STAT_CPU_BATCH);
-
-	if (op_is_sync(op))
-		cnt = &rwstat->cpu_cnt[BLKG_RWSTAT_SYNC];
-	else
-		cnt = &rwstat->cpu_cnt[BLKG_RWSTAT_ASYNC];
-
-	percpu_counter_add_batch(cnt, val, BLKG_STAT_CPU_BATCH);
-}
-
-/**
- * blkg_rwstat_read - read the current values of a blkg_rwstat
- * @rwstat: blkg_rwstat to read
- *
- * Read the current snapshot of @rwstat and return it in the aux counts.
- */
-static inline void blkg_rwstat_read(struct blkg_rwstat *rwstat,
-		struct blkg_rwstat_sample *result)
-{
-	int i;
-
-	for (i = 0; i < BLKG_RWSTAT_NR; i++)
-		result->cnt[i] =
-			percpu_counter_sum_positive(&rwstat->cpu_cnt[i]);
-}
-
-/**
- * blkg_rwstat_total - read the total count of a blkg_rwstat
- * @rwstat: blkg_rwstat to read
- *
- * Return the total count of @rwstat regardless of the IO direction.  This
- * function can be called without synchronization and takes care of u64
- * atomicity.
- */
-static inline uint64_t blkg_rwstat_total(struct blkg_rwstat *rwstat)
-{
-	struct blkg_rwstat_sample tmp = { };
-
-	blkg_rwstat_read(rwstat, &tmp);
-	return tmp.cnt[BLKG_RWSTAT_READ] + tmp.cnt[BLKG_RWSTAT_WRITE];
-}
-
-/**
- * blkg_rwstat_reset - reset a blkg_rwstat
- * @rwstat: blkg_rwstat to reset
- */
-static inline void blkg_rwstat_reset(struct blkg_rwstat *rwstat)
-{
-	int i;
-
-	for (i = 0; i < BLKG_RWSTAT_NR; i++) {
-		percpu_counter_set(&rwstat->cpu_cnt[i], 0);
-		atomic64_set(&rwstat->aux_cnt[i], 0);
-	}
-}
-
-/**
- * blkg_rwstat_add_aux - add a blkg_rwstat into another's aux count
- * @to: the destination blkg_rwstat
- * @from: the source
- *
- * Add @from's count including the aux one to @to's aux count.
- */
-static inline void blkg_rwstat_add_aux(struct blkg_rwstat *to,
-				       struct blkg_rwstat *from)
-{
-	u64 sum[BLKG_RWSTAT_NR];
-	int i;
-
-	for (i = 0; i < BLKG_RWSTAT_NR; i++)
-		sum[i] = percpu_counter_sum_positive(&from->cpu_cnt[i]);
-
-	for (i = 0; i < BLKG_RWSTAT_NR; i++)
-		atomic64_add(sum[i] + atomic64_read(&from->aux_cnt[i]),
-			     &to->aux_cnt[i]);
-}
-
 #ifdef CONFIG_BLK_DEV_THROTTLING
 extern bool blk_throtl_bio(struct request_queue *q, struct blkcg_gq *blkg,
 			   struct bio *bio);