Re: [PATCH 40/45] block: move bio io prio to a new field

Hannes Reinecke
2016-06-06T06:51:05Z

On 06/05/2016 09:32 PM, mchristi@redhat.com wrote:
> From: Mike Christie <mchristi@redhat.com>
>
> In the next patch, we move drop the compat code and make
> the op a separate value that is hidden in bi_rw. To give
> the op and rq bits flags room to grow this moves prio to
> its own field.
>
> Signed-off-by: Mike Christie <mchristi@redhat.com>
> ---
> include/linux/bio.h | 14 ++------------
> include/linux/blk_types.h | 5 ++---
> 2 files changed, 4 insertions(+), 15 deletions(-)
>
> diff --git a/include/linux/bio.h b/include/linux/bio.h
> index 4568647..35108c2 100644
> --- a/include/linux/bio.h
> +++ b/include/linux/bio.h
> @@ -47,18 +47,8 @@
> #define bio_op(bio) (op_from_rq_bits((bio)->bi_rw))
> #define bio_set_op_attrs(bio, op, flags) ((bio)->bi_rw |= (op | flags))
>
> -/*
> - * upper 16 bits of bi_rw define the io priority of this bio
> - */
> -#define BIO_PRIO_SHIFT (8 * sizeof(unsigned long) - IOPRIO_BITS)
> -#define bio_prio(bio) ((bio)->bi_rw >> BIO_PRIO_SHIFT)
> -#define bio_prio_valid(bio) ioprio_valid(bio_prio(bio))
> -
> -#define bio_set_prio(bio, prio) do { \
> - WARN_ON(prio >= (1 << IOPRIO_BITS)); \
> - (bio)->bi_rw &= ((1UL << BIO_PRIO_SHIFT) - 1); \
> - (bio)->bi_rw |= ((unsigned long) (prio) << BIO_PRIO_SHIFT); \
> -} while (0)
> +#define bio_prio(bio) (bio)->bi_ioprio
> +#define bio_set_prio(bio, prio) ((bio)->bi_ioprio = prio)
>
> /*
> * various member access, note that bio_data should of course not be used
> diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h
> index 6e60baa..2738413 100644
> --- a/include/linux/blk_types.h
> +++ b/include/linux/blk_types.h
> @@ -48,9 +48,8 @@ struct bio {
> struct block_device *bi_bdev;
> unsigned int bi_flags; /* status, command, etc */
> int bi_error;
> - unsigned long bi_rw; /* bottom bits READ/WRITE,
> - * top bits priority
> - */
> + unsigned long bi_rw; /* READ/WRITE */
> + unsigned short bi_ioprio;
>
> struct bvec_iter bi_iter;
>
>
Reviewed-by: Hannes Reinecke <hare@suse.com>

Cheers,

Hannes
--
Dr. Hannes Reinecke Teamlead Storage & Networking
hare@suse.de +49 911 74053 688
SUSE LINUX GmbH, Maxfeldstr. 5, 90409 Nürnberg
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