Re: [dm-devel] [PATCH v3 05/16] block: Kill bi_destructor

[Tejun Heo <tj kernel org>]

On Fri, May 25, 2012 at 01:25:28PM -0700, Kent Overstreet wrote:
> Now that we've got generic code for freeing bios allocated from bio
> pools, this isn't needed anymore.
> 
> This also changes the semantics of bio_free() a bit - it now also frees
> bios allocated by bio_kmalloc(). It's also no longer exported, as
> without bi_destructor there should be no need for it to be called
> anywhere else.

I like this patch but I'd *really* like to see the patch description
giving some background and explains *why* this is a good change.

> diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h
> index 6b7daf3..b6ddbf1 100644
> --- a/include/linux/blk_types.h
> +++ b/include/linux/blk_types.h
> @@ -74,11 +74,8 @@ struct bio {
>  	struct bio_integrity_payload *bi_integrity;  /* data integrity */
>  #endif
>  
> -	/* If bi_pool is non NULL, bi_destructor is not called */
>  	struct bio_set		*bi_pool;

Maybe explain that %NULL bi_pool indicates kmalloc backed allocation?

-- 
tejun