[dm-devel] [Bcache v13 11/16] bcache: Core btree code

Tejun Heo tj at kernel.org
Wed May 30 07:47:08 UTC 2012


A couple more comments from this round of reading.

On Wed, May 09, 2012 at 11:10:48PM -0400, Kent Overstreet wrote:
> +#define btree_prio		USHRT_MAX
> +#define initial_prio		32768

Why are these in lower case?

> +#define PTR_BUCKET(c, k, n)						\
> +	(PTR_CACHE(c, k, n)->buckets + PTR_BUCKET_NR(c, k, n))

PTR_BUCKET(c, k, n)

Awesome.  I don't know what type it takes or what each single
character argument stands for.

> +static inline bool cached_dev_get(struct cached_dev *d)
> +{
> +	if (!atomic_inc_not_zero(&d->count))
> +		return false;
> +
> +	smp_mb__after_atomic_inc();

What is this mb() paired with?  Whenever using a mb, please specify
what the mb is paired with.

> +	return true;
> +}

Thanks.

-- 
tejun




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