Re: [RFC PATCH] fs: make s_count atomic_t

[Al Viro <viro@zeniv.linux.org.uk>]

On Fri, Nov 03, 2023 at 09:19:08AM +0100, Christoph Hellwig wrote:
> Same feeling as Jan here - this looks fine to me, but I wonder if there's
> much of a need.  Maybe run it past Al if he has any opinion?

[resurfaces from dcache stuff]

TBH, I'd rather see documentation of struct super_block life cycle
rules written up, just to see what ends up being too ugly to document ;-/
I have old notes on that stuff, but they are pretty much invalidated by
the rework that happened this summer...

I don't hate making ->s_count atomic, but short of real evidence that
sb_lock gets serious contention, I don't see much point either way.

PS: Re dcache - I've a growing branch with a bunch of massage in that area,
plus the local attempt at documentation that will go there.  How are we
going to manage the trees?  The coming cycle I'm probably back to normal
amount of activity; the summer had been a fucking nightmare, but the things
have settled down by now...  <looks> at least 5 topical branches, just
going by what I've got at the moment.