[PATCH] block/throttle: Call throtl_update_dispatch_stats with throtl_grp directly.

[PATCH] block/throttle: Call throtl_update_dispatch_stats with throtl_grp directly.

[Tao Ma]

From: Tao Ma <boyu.mt@taobao.com>

All callers of throtl_update_dispatch_stats uses tg_to_blkg and then
in this function we use blkg_to_tg again to change it back. So remove
all these useless conversion and use throtl_grp directly to call
throtl_update_dispatch_stats.

Cc: Tejun Heo <tj@kernel.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Tao Ma <boyu.mt@taobao.com>
---
 block/blk-throttle.c |    7 +++----
 1 files changed, 3 insertions(+), 4 deletions(-)

diff --git a/block/blk-throttle.c b/block/blk-throttle.c
index e287c19..1588c2d 100644
--- a/block/blk-throttle.c
+++ b/block/blk-throttle.c
@@ -675,10 +675,9 @@ static bool tg_may_dispatch(struct throtl_data *td, struct throtl_grp *tg,
 	return 0;
 }
 
-static void throtl_update_dispatch_stats(struct blkcg_gq *blkg, u64 bytes,
+static void throtl_update_dispatch_stats(struct throtl_grp *tg, u64 bytes,
 					 int rw)
 {
-	struct throtl_grp *tg = blkg_to_tg(blkg);
 	struct tg_stats_cpu *stats_cpu;
 	unsigned long flags;
 
@@ -709,7 +708,7 @@ static void throtl_charge_bio(struct throtl_grp *tg, struct bio *bio)
 	tg->bytes_disp[rw] += bio->bi_size;
 	tg->io_disp[rw]++;
 
-	throtl_update_dispatch_stats(tg_to_blkg(tg), bio->bi_size, bio->bi_rw);
+	throtl_update_dispatch_stats(tg, bio->bi_size, bio->bi_rw);
 }
 
 static void throtl_add_bio_tg(struct throtl_data *td, struct throtl_grp *tg,
@@ -1133,7 +1132,7 @@ bool blk_throtl_bio(struct request_queue *q, struct bio *bio)
 	tg = throtl_lookup_tg(td, blkcg);
 	if (tg) {
 		if (tg_no_rule_group(tg, rw)) {
-			throtl_update_dispatch_stats(tg_to_blkg(tg),
+			throtl_update_dispatch_stats(tg,
 						     bio->bi_size, bio->bi_rw);
 			goto out_unlock_rcu;
 		}
-- 
1.7.0.4

Re: [PATCH] block/throttle: Call throtl_update_dispatch_stats with throtl_grp directly.

[Vivek Goyal]

On Fri, Aug 31, 2012 at 01:08:23PM +0800, Tao Ma wrote:
> From: Tao Ma <boyu.mt@taobao.com>
> 
> All callers of throtl_update_dispatch_stats uses tg_to_blkg and then
> in this function we use blkg_to_tg again to change it back. So remove
> all these useless conversion and use throtl_grp directly to call
> throtl_update_dispatch_stats.
> 
> Cc: Tejun Heo <tj@kernel.org>
> Cc: Vivek Goyal <vgoyal@redhat.com>
> Cc: Jens Axboe <axboe@kernel.dk>
> Signed-off-by: Tao Ma <boyu.mt@taobao.com>
> ---

Simple. Looks good.

Acked-by: Vivek Goyal <vgoyal@redhat.com>

Vivek

>  block/blk-throttle.c |    7 +++----
>  1 files changed, 3 insertions(+), 4 deletions(-)
> 
> diff --git a/block/blk-throttle.c b/block/blk-throttle.c
> index e287c19..1588c2d 100644
> --- a/block/blk-throttle.c
> +++ b/block/blk-throttle.c
> @@ -675,10 +675,9 @@ static bool tg_may_dispatch(struct throtl_data *td, struct throtl_grp *tg,
>  	return 0;
>  }
>  
> -static void throtl_update_dispatch_stats(struct blkcg_gq *blkg, u64 bytes,
> +static void throtl_update_dispatch_stats(struct throtl_grp *tg, u64 bytes,
>  					 int rw)
>  {
> -	struct throtl_grp *tg = blkg_to_tg(blkg);
>  	struct tg_stats_cpu *stats_cpu;
>  	unsigned long flags;
>  
> @@ -709,7 +708,7 @@ static void throtl_charge_bio(struct throtl_grp *tg, struct bio *bio)
>  	tg->bytes_disp[rw] += bio->bi_size;
>  	tg->io_disp[rw]++;
>  
> -	throtl_update_dispatch_stats(tg_to_blkg(tg), bio->bi_size, bio->bi_rw);
> +	throtl_update_dispatch_stats(tg, bio->bi_size, bio->bi_rw);
>  }
>  
>  static void throtl_add_bio_tg(struct throtl_data *td, struct throtl_grp *tg,
> @@ -1133,7 +1132,7 @@ bool blk_throtl_bio(struct request_queue *q, struct bio *bio)
>  	tg = throtl_lookup_tg(td, blkcg);
>  	if (tg) {
>  		if (tg_no_rule_group(tg, rw)) {
> -			throtl_update_dispatch_stats(tg_to_blkg(tg),
> +			throtl_update_dispatch_stats(tg,
>  						     bio->bi_size, bio->bi_rw);
>  			goto out_unlock_rcu;
>  		}
> -- 
> 1.7.0.4