[dm-devel] [PATCH v3 1/3] block: add bio_start_io_acct_time() to control start_time

[Christoph Hellwig]

On Thu, Jan 27, 2022 at 11:17:51PM -0500, Mike Snitzer wrote:
> +	__part_start_io_acct(bio->bi_bdev, bio_sectors(bio),
> +			     bio_op(bio), start_time);
>  }
> +EXPORT_SYMBOL_GPL(bio_start_io_acct_time);
>  
>  /**
>   * bio_start_io_acct - start I/O accounting for bio based drivers
> @@ -1084,14 +1096,15 @@ static unsigned long __part_start_io_acct(struct block_device *part,
>   */
>  unsigned long bio_start_io_acct(struct bio *bio)
>  {
> -	return __part_start_io_acct(bio->bi_bdev, bio_sectors(bio), bio_op(bio));
> +	return __part_start_io_acct(bio->bi_bdev, bio_sectors(bio),
> +				    bio_op(bio), jiffies);

Is droppingthe READ_ONCE safe here?  This is a honest question as these
helpers still confuse me.

The rest looks good:

Reviewed-by: Christoph Hellwig <hch at lst.de>