[PATCH 2/2] block, bfq: delete "bfq" prefix from cgroup filenames

[Paolo Valente]

From: Angelo Ruocco <angeloruocco90@xxxxxxxxx>

When bfq was merged into mainline, there were two I/O schedulers that
implemented the proportional-share policy: bfq for blk-mq and cfq for
legacy blk. bfq's interface files in the blkio/io controller have the
same names as cfq. But the cgroups interface doesn't allow two
entities to use the same name for their files, so for bfq we had to
prepend the "bfq" prefix to each of its files. However no legacy code
uses these modified file names. This naming also causes confusion, as,
e.g., in [1].

Now cfq has gone with legacy blk, so there is no need any longer for
these prefixes in (the never used) bfq names. In view of this fact, this
commit removes these prefixes, thereby enabling legacy code to truly
use the proportional share policy in blk-mq.

[1] https://github.com/systemd/systemd/issues/7057

Signed-off-by: Angelo Ruocco <angeloruocco90@xxxxxxxxx>
Signed-off-by: Paolo Valente <paolo.valente@xxxxxxxxxx>
---
 block/bfq-cgroup.c | 46 +++++++++++++++++++++++-----------------------
 1 file changed, 23 insertions(+), 23 deletions(-)

diff --git a/block/bfq-cgroup.c b/block/bfq-cgroup.c
index decda96770f4..7f0160f5155f 100644
--- a/block/bfq-cgroup.c
+++ b/block/bfq-cgroup.c
@@ -1213,7 +1213,7 @@ struct blkcg_policy blkcg_policy_bfq = {
 
 struct cftype bfq_blkcg_legacy_files[] = {
 	{
-		.name = "bfq.weight",
+		.name = "weight",
 		.flags = CFTYPE_NOT_ON_ROOT,
 		.seq_show = bfq_io_show_weight_legacy,
 		.write_u64 = bfq_io_set_weight_legacy,
@@ -1227,42 +1227,42 @@ struct cftype bfq_blkcg_legacy_files[] = {
 
 	/* statistics, covers only the tasks in the bfqg */
 	{
-		.name = "bfq.io_service_bytes",
+		.name = "io_service_bytes",
 		.private = (unsigned long)&blkcg_policy_bfq,
 		.seq_show = blkg_print_stat_bytes,
 	},
 	{
-		.name = "bfq.io_serviced",
+		.name = "io_serviced",
 		.private = (unsigned long)&blkcg_policy_bfq,
 		.seq_show = blkg_print_stat_ios,
 	},
 #ifdef CONFIG_BFQ_CGROUP_DEBUG
 	{
-		.name = "bfq.time",
+		.name = "time",
 		.private = offsetof(struct bfq_group, stats.time),
 		.seq_show = bfqg_print_stat,
 	},
 	{
-		.name = "bfq.sectors",
+		.name = "sectors",
 		.seq_show = bfqg_print_stat_sectors,
 	},
 	{
-		.name = "bfq.io_service_time",
+		.name = "io_service_time",
 		.private = offsetof(struct bfq_group, stats.service_time),
 		.seq_show = bfqg_print_rwstat,
 	},
 	{
-		.name = "bfq.io_wait_time",
+		.name = "io_wait_time",
 		.private = offsetof(struct bfq_group, stats.wait_time),
 		.seq_show = bfqg_print_rwstat,
 	},
 	{
-		.name = "bfq.io_merged",
+		.name = "io_merged",
 		.private = offsetof(struct bfq_group, stats.merged),
 		.seq_show = bfqg_print_rwstat,
 	},
 	{
-		.name = "bfq.io_queued",
+		.name = "io_queued",
 		.private = offsetof(struct bfq_group, stats.queued),
 		.seq_show = bfqg_print_rwstat,
 	},
@@ -1270,66 +1270,66 @@ struct cftype bfq_blkcg_legacy_files[] = {
 
 	/* the same statistics which cover the bfqg and its descendants */
 	{
-		.name = "bfq.io_service_bytes_recursive",
+		.name = "io_service_bytes_recursive",
 		.private = (unsigned long)&blkcg_policy_bfq,
 		.seq_show = blkg_print_stat_bytes_recursive,
 	},
 	{
-		.name = "bfq.io_serviced_recursive",
+		.name = "io_serviced_recursive",
 		.private = (unsigned long)&blkcg_policy_bfq,
 		.seq_show = blkg_print_stat_ios_recursive,
 	},
 #ifdef CONFIG_BFQ_CGROUP_DEBUG
 	{
-		.name = "bfq.time_recursive",
+		.name = "time_recursive",
 		.private = offsetof(struct bfq_group, stats.time),
 		.seq_show = bfqg_print_stat_recursive,
 	},
 	{
-		.name = "bfq.sectors_recursive",
+		.name = "sectors_recursive",
 		.seq_show = bfqg_print_stat_sectors_recursive,
 	},
 	{
-		.name = "bfq.io_service_time_recursive",
+		.name = "io_service_time_recursive",
 		.private = offsetof(struct bfq_group, stats.service_time),
 		.seq_show = bfqg_print_rwstat_recursive,
 	},
 	{
-		.name = "bfq.io_wait_time_recursive",
+		.name = "io_wait_time_recursive",
 		.private = offsetof(struct bfq_group, stats.wait_time),
 		.seq_show = bfqg_print_rwstat_recursive,
 	},
 	{
-		.name = "bfq.io_merged_recursive",
+		.name = "io_merged_recursive",
 		.private = offsetof(struct bfq_group, stats.merged),
 		.seq_show = bfqg_print_rwstat_recursive,
 	},
 	{
-		.name = "bfq.io_queued_recursive",
+		.name = "io_queued_recursive",
 		.private = offsetof(struct bfq_group, stats.queued),
 		.seq_show = bfqg_print_rwstat_recursive,
 	},
 	{
-		.name = "bfq.avg_queue_size",
+		.name = "avg_queue_size",
 		.seq_show = bfqg_print_avg_queue_size,
 	},
 	{
-		.name = "bfq.group_wait_time",
+		.name = "group_wait_time",
 		.private = offsetof(struct bfq_group, stats.group_wait_time),
 		.seq_show = bfqg_print_stat,
 	},
 	{
-		.name = "bfq.idle_time",
+		.name = "idle_time",
 		.private = offsetof(struct bfq_group, stats.idle_time),
 		.seq_show = bfqg_print_stat,
 	},
 	{
-		.name = "bfq.empty_time",
+		.name = "empty_time",
 		.private = offsetof(struct bfq_group, stats.empty_time),
 		.seq_show = bfqg_print_stat,
 	},
 	{
-		.name = "bfq.dequeue",
+		.name = "dequeue",
 		.private = offsetof(struct bfq_group, stats.dequeue),
 		.seq_show = bfqg_print_stat,
 	},
@@ -1339,7 +1339,7 @@ struct cftype bfq_blkcg_legacy_files[] = {
 
 struct cftype bfq_blkg_files[] = {
 	{
-		.name = "bfq.weight",
+		.name = "weight",
 		.flags = CFTYPE_NOT_ON_ROOT,
 		.seq_show = bfq_io_show_weight,
 		.write = bfq_io_set_weight,
-- 
2.20.1