Add `struct elv_change_ctx` and prepare for unifying elevator_change(),
with this way, any input & output parameter can be provided & observed
in top caller.
This way also helps to move kobject & debugfs things out of
->elevator_lock & freezing queue.
Signed-off-by: Ming Lei <ming.lei@xxxxxxxxxx>
---
block/blk-mq.c | 16 ++++++++++------
block/blk.h | 4 ++--
block/elevator.c | 33 +++++++++++++++++++--------------
block/elevator.h | 7 +++++++
4 files changed, 38 insertions(+), 22 deletions(-)
diff --git a/block/blk-mq.c b/block/blk-mq.c
index 0f4a5e674874..1a287c2e791c 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -4984,16 +4984,20 @@ static void __blk_mq_update_nr_hw_queues(struct blk_mq_tag_set *set,
}
list_for_each_entry(q, &set->tag_list, tag_set_list) {
- const char *name = "none";
-
- mutex_lock(&q->elevator_lock);
- if (q->elevator && !blk_queue_dying(q))
- name = q->elevator->type->elevator_name;
/*
* nr_hw_queues is changed and elevator data depends on
* it, so we have to force to rebuild elevator
*/
- __elevator_change(q, name, true);
+ struct elv_change_ctx ctx = {
+ .name = "none",
+ .force = true,
+ .uevent = true,
+ };
+
+ mutex_lock(&q->elevator_lock);
+ if (q->elevator && !blk_queue_dying(q))
+ ctx.name = q->elevator->type->elevator_name;
+ __elevator_change(q, &ctx);
mutex_unlock(&q->elevator_lock);
}
diff --git a/block/blk.h b/block/blk.h
index 0c3cc1af2525..be01cb9f3910 100644
--- a/block/blk.h
+++ b/block/blk.h
@@ -12,6 +12,7 @@
#include "blk-crypto-internal.h"
struct elevator_type;
+struct elv_change_ctx;
#define BLK_DEV_MAX_SECTORS (LLONG_MAX >> 9)
#define BLK_MIN_SEGMENT_SIZE 4096
@@ -319,8 +320,7 @@ bool blk_bio_list_merge(struct request_queue *q, struct list_head *list,
bool blk_insert_flush(struct request *rq);
-int __elevator_change(struct request_queue *q, const char *elevator_name,
- bool force);
+int __elevator_change(struct request_queue *q, struct elv_change_ctx *ctx);
void elevator_exit(struct request_queue *q);
int elv_register_queue(struct request_queue *q, bool uevent);
void elv_unregister_queue(struct request_queue *q);
diff --git a/block/elevator.c b/block/elevator.c
index 6bf3871c7164..836138fc148a 100644
--- a/block/elevator.c
+++ b/block/elevator.c
@@ -53,7 +53,8 @@ static LIST_HEAD(elv_list);
*/
#define rq_hash_key(rq) (blk_rq_pos(rq) + blk_rq_sectors(rq))
-static int elevator_change(struct request_queue *q, const char *name);
+static int elevator_change(struct request_queue *q,
+ struct elv_change_ctx *ctx);
/*
* Query io scheduler to see if the current process issuing bio may be
@@ -623,7 +624,8 @@ void elevator_init_mq(struct request_queue *q)
* If switching fails, we are most likely running out of memory and not able
* to restore the old io scheduler, so leaving the io scheduler being none.
*/
-static int elevator_switch(struct request_queue *q, struct elevator_type *new_e)
+static int elevator_switch(struct request_queue *q, struct elevator_type *new_e,
+ struct elv_change_ctx *ctx)
{
int ret;
@@ -641,7 +643,7 @@ static int elevator_switch(struct request_queue *q, struct elevator_type *new_e)
if (ret)
goto out_unfreeze;
- ret = elv_register_queue(q, true);
+ ret = elv_register_queue(q, ctx->uevent);
if (ret) {
elevator_exit(q);
goto out_unfreeze;
@@ -679,9 +681,9 @@ static void elevator_disable(struct request_queue *q)
/*
* Switch this queue to the given IO scheduler.
*/
-int __elevator_change(struct request_queue *q, const char *elevator_name,
- bool force)
+int __elevator_change(struct request_queue *q, struct elv_change_ctx *ctx)
{
+ const char *elevator_name = ctx->name;
struct elevator_type *e;
int ret;
@@ -695,19 +697,20 @@ int __elevator_change(struct request_queue *q, const char *elevator_name,
return 0;
}
- if (!force && q->elevator &&
+ if (!ctx->force && q->elevator &&
elevator_match(q->elevator->type, elevator_name))
return 0;
e = elevator_find_get(elevator_name);
if (!e)
return -EINVAL;
- ret = elevator_switch(q, e);
+ ret = elevator_switch(q, e, ctx);
elevator_put(e);
return ret;
}
-static int elevator_change(struct request_queue *q, const char *name)
+static int elevator_change(struct request_queue *q,
+ struct elv_change_ctx *ctx)
{
struct blk_mq_tag_set *set = q->tag_set;
unsigned int memflags;
@@ -721,7 +724,7 @@ static int elevator_change(struct request_queue *q, const char *name)
memflags = blk_mq_freeze_queue(q);
mutex_lock(&q->elevator_lock);
- ret = __elevator_change(q, name, false);
+ ret = __elevator_change(q, ctx);
mutex_unlock(&q->elevator_lock);
blk_mq_unfreeze_queue(q, memflags);
exit:
@@ -729,7 +732,7 @@ static int elevator_change(struct request_queue *q, const char *name)
return ret;
}
-static void elv_iosched_load_module(char *elevator_name)
+static void elv_iosched_load_module(const char *elevator_name)
{
struct elevator_type *found;
@@ -746,7 +749,9 @@ ssize_t elv_iosched_store(struct gendisk *disk, const char *buf,
{
struct request_queue *q = disk->queue;
char elevator_name[ELV_NAME_MAX];
- char *name;
+ struct elv_change_ctx ctx = {
+ .uevent = true,
+ };
int ret;
/*
@@ -755,11 +760,11 @@ ssize_t elv_iosched_store(struct gendisk *disk, const char *buf,
* queue is the one for the device storing the module file.
*/
strscpy(elevator_name, buf, sizeof(elevator_name));
- name = strstrip(elevator_name);
+ ctx.name = strstrip(elevator_name);
- elv_iosched_load_module(name);
+ elv_iosched_load_module(ctx.name);
- ret = elevator_change(q, name);
+ ret = elevator_change(q, &ctx);
if (!ret)
ret = count;
return ret;
diff --git a/block/elevator.h b/block/elevator.h
index 9198676644a9..63fc4cad16cc 100644
--- a/block/elevator.h
+++ b/block/elevator.h
@@ -122,6 +122,13 @@ struct elevator_queue
#define ELEVATOR_FLAG_REGISTERED 0
+/* Holding context data for changing elevator */
+struct elv_change_ctx {
+ const char *name;
+ bool force;
+ bool uevent;
+};
+
/*
* block elevator interface
*/
--
2.47.0
