Re: semantics of rhashtable and sysvipc

[Linus Torvalds]

On Thu, May 24, 2018 at 12:08 PM Davidlohr Bueso <dave@xxxxxxxxxxxx> wrote:


> However, after how about the resize being based on HASH_MIN_SIZE instead
of
> HASH_DEFAULT_SIZE?

I think that sounds reasonable. We wouldn't expect this to ever happen in
practice, and as you say, if it *does* happen, the size of the hash array
is the last of our problems.

> Considering that some users set p.min_size to be rather large-ish (up to
1024
> buckets afaict), we'd need the following:

>          size = min(ht->p.min_size, HASH_MIN_SIZE);

Bah, let's just go for simplicity, and just make it HASH_MIN_SIZE
unconditionally, and just have a single fallback: if the first "normal"
allocation fails, do one single unconditional allocation with HASH_MIN_SIZE
and GFP_NOFAIL.

I think that should work fine.

                Linus