On 08/01/2012 08:27 PM, Tejun Heo wrote:

On Wed, Aug 01, 2012 at 08:24:32PM +0200, Sasha Levin wrote:

quoted

On 08/01/2012 08:21 PM, Tejun Heo wrote:

quoted

On Wed, Aug 01, 2012 at 08:19:52PM +0200, Sasha Levin wrote:

quoted

If we switch to using functions, we could no longer hide it anywhere
(we'd need to either turn the buckets into a struct, or have the
user pass it around to all functions).

Create an outer struct hash_table which remembers the size?

Possible. I just wanted to avoid creating new structs where they're not really required.

Do you think it's worth it for eliminating those two macros?

What if someone wants to allocate hashtable dynamically which isn't
too unlikely?  I think it's best to stay away from macro tricks as
much as possible although I gotta admit I fall into the macro trap
more often than I would like.

Using a struct makes the dynamic case much easier, but it complicates the static case.

Previously we could create the buckets statically.

Consider this struct:

struct hash_table {
	u32 bits;
	struct hlist_head buckets[];
};

We can't make any code that wraps this to make it work properly statically allocated nice enough to be acceptable.


What if when creating the buckets, we actually allocate bits+1 buckets, and use the last bucket not as a bucket but as the bitcount? It looks like a hack but I think it's much nicer than the previous.

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