[dm-devel] [PATCH 10/11] block: use block_bio class for getrq and sleeprq

[Chaitanya Kulkarni]

On 6/29/20 10:13 PM, Christoph Hellwig wrote:
> On Mon, Jun 29, 2020 at 04:43:13PM -0700, Chaitanya Kulkarni wrote:
>> The only difference in block_get_rq and block_bio was the last param
>> passed  __entry->nr_sector & bio->bi_iter.bi_size respectively. Since
>> that is not the case anymore replace block_get_rq class with block_bio
>> for block_getrq and block_sleeprq events, also adjust the code to handle
>> null bio case in block_bio.
> To me it seems like keeping the NULL bio case separate actually is a
> little simpler..
> 
> 

Keeping it separate will have an extra event class and related
event(s) for only handling null bio case.

Also the block_get_rq class uses 4 comparisons with ?:.
This patch reduces it to only one comparison in fast path.

With above explanation does it make sense to get rid of the
blk_get_rq ?