Re: [PATCH 3/6] md/bcache: use generic io stats accounting functions to simplify io stat accounting

Re: [PATCH 3/6] md/bcache: use generic io stats accounting functions to simplify io stat accounting

[Kent Overstreet]

On Mon, Nov 24, 2014 at 11:05:24AM +0800, Gu Zheng wrote:
> Use generic io stats accounting help functions (generic_{start,end}_io_acct)
> to simplify io stat accounting.
> 
> Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com>

Cool!

Acked-by: Kent Overstreet <kmo@datera.io>

> ---
>  drivers/md/bcache/request.c |   23 ++++++-----------------
>  1 files changed, 6 insertions(+), 17 deletions(-)
> 
> diff --git a/drivers/md/bcache/request.c b/drivers/md/bcache/request.c
> index 62e6e98..ab43fad 100644
> --- a/drivers/md/bcache/request.c
> +++ b/drivers/md/bcache/request.c
> @@ -601,13 +601,8 @@ static void request_endio(struct bio *bio, int error)
>  static void bio_complete(struct search *s)
>  {
>  	if (s->orig_bio) {
> -		int cpu, rw = bio_data_dir(s->orig_bio);
> -		unsigned long duration = jiffies - s->start_time;
> -
> -		cpu = part_stat_lock();
> -		part_round_stats(cpu, &s->d->disk->part0);
> -		part_stat_add(cpu, &s->d->disk->part0, ticks[rw], duration);
> -		part_stat_unlock();
> +		generic_end_io_acct(bio_data_dir(s->orig_bio),
> +				    &s->d->disk->part0, s->start_time);
>  
>  		trace_bcache_request_end(s->d, s->orig_bio);
>  		bio_endio(s->orig_bio, s->iop.error);
> @@ -959,12 +954,9 @@ static void cached_dev_make_request(struct request_queue *q, struct bio *bio)
>  	struct search *s;
>  	struct bcache_device *d = bio->bi_bdev->bd_disk->private_data;
>  	struct cached_dev *dc = container_of(d, struct cached_dev, disk);
> -	int cpu, rw = bio_data_dir(bio);
> +	int rw = bio_data_dir(bio);
>  
> -	cpu = part_stat_lock();
> -	part_stat_inc(cpu, &d->disk->part0, ios[rw]);
> -	part_stat_add(cpu, &d->disk->part0, sectors[rw], bio_sectors(bio));
> -	part_stat_unlock();
> +	generic_start_io_acct(rw, bio_sectors(bio), &d->disk->part0);
>  
>  	bio->bi_bdev = dc->bdev;
>  	bio->bi_iter.bi_sector += dc->sb.data_offset;
> @@ -1074,12 +1066,9 @@ static void flash_dev_make_request(struct request_queue *q, struct bio *bio)
>  	struct search *s;
>  	struct closure *cl;
>  	struct bcache_device *d = bio->bi_bdev->bd_disk->private_data;
> -	int cpu, rw = bio_data_dir(bio);
> +	int rw = bio_data_dir(bio);
>  
> -	cpu = part_stat_lock();
> -	part_stat_inc(cpu, &d->disk->part0, ios[rw]);
> -	part_stat_add(cpu, &d->disk->part0, sectors[rw], bio_sectors(bio));
> -	part_stat_unlock();
> +	generic_start_io_acct(rw, bio_sectors(bio), &d->disk->part0);
>  
>  	s = search_alloc(bio, d);
>  	cl = &s->cl;
> -- 
> 1.7.7
> 

Re: [PATCH 0/6] blk: introduce generic io stat accounting help function

[Jens Axboe]

On 11/23/2014 08:05 PM, Gu Zheng wrote:
> Many block drivers accounting io stat based on bio (e.g. NVMe...),
> the blk_account_io_start/end() which is based on request
> does not make sense to them, so here we introduce the similar help
> function named generic_start/end_io_acct base on raw sectors, and it can
> simplify some driver's open io accounting code.
>
> Gu Zheng (6):
>    blk: introduce generic io stat accounting help function
>    NVMe: use generic io stat accounting functions to simplify
>      nvme_start/end_io_acct
>    md/bcache: use generic io stats accounting functions to simplify io
>      stat accounting
>    drbd: use generic io stats accounting functions to simplify io stat
>      accounting
>    md: use generic io stats accounting functions to simplify io stat
>      accounting
>    block/rsxx: use generic io stats accounting functions to simplify io
>      stat accounting

Thanks, this looks good. I'll apply it, except 2/6, since nvme no longer 
uses them.

-- 
Jens Axboe

Re: [PATCH 0/6] blk: introduce generic io stat accounting help function

[Gu Zheng]

On 11/24/2014 11:03 PM, Jens Axboe wrote:

> On 11/23/2014 08:05 PM, Gu Zheng wrote:
>> Many block drivers accounting io stat based on bio (e.g. NVMe...),
>> the blk_account_io_start/end() which is based on request
>> does not make sense to them, so here we introduce the similar help
>> function named generic_start/end_io_acct base on raw sectors, and it can
>> simplify some driver's open io accounting code.
>>
>> Gu Zheng (6):
>>    blk: introduce generic io stat accounting help function
>>    NVMe: use generic io stat accounting functions to simplify
>>      nvme_start/end_io_acct
>>    md/bcache: use generic io stats accounting functions to simplify io
>>      stat accounting
>>    drbd: use generic io stats accounting functions to simplify io stat
>>      accounting
>>    md: use generic io stats accounting functions to simplify io stat
>>      accounting
>>    block/rsxx: use generic io stats accounting functions to simplify io
>>      stat accounting
> 
> Thanks, this looks good. I'll apply it, except 2/6, since nvme no longer uses them.

OK.

Thanks,
Gu

>