Re: [PATCH 86/87] fs: switch timespec64 fields in inode to discrete integers

From: Jeff Layton <jlayton@kernel.org>
To: Christian Brauner <brauner@kernel.org>
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Subject: Re: [PATCH 86/87] fs: switch timespec64 fields in inode to discrete integers
Date: Fri, 29 Sep 2023 06:16:57 -0400	[thread overview]
Message-ID: <d52b4330cd26e8ef9b2999281b05e50bd7106b3a.camel@kernel.org> (raw)
In-Reply-To: <20230929-yuppie-unzweifelhaft-434bf13bc964@brauner>

On Fri, 2023-09-29 at 11:44 +0200, Christian Brauner wrote:
> > It is a lot of churn though.
> 
> I think that i_{a,c,m}time shouldn't be accessed directly by
> filesystems same as no filesystem should really access i_{g,u}id which
> we also provide i_{g,u}id_{read,write}() accessors for. The mode is
> another example where really most often should use helpers because of all
> the set*id stripping that we need to do (and the bugs that we had
> because of this...).
> 
> The interdependency between ctime and mtime is enough to hide this in
> accessors. The other big advantage is simply grepability. So really I
> would like to see this change even without the type switch.
> 
> In other words, there's no need to lump the two changes together. Do the
> conversion part and we can argue about the switch to discrete integers
> separately.
> 
> The other adavantage is that we have a cycle to see any possible
> regression from the conversion.
> 
> Thoughts anyone?

That works for me, and sort of what I was planning anyway. I mostly just
did the change to timestamp storage to see what it would look like
afterward.

FWIW, I'm planning to do a v2 patchbomb early next week, with the
changes that Chuck suggested (specific helpers for fetching the _sec and
_nsec fields). For now, I'll drop the change from timespec64 to discrete
fields. We can do that in a separate follow-on set.
-- 
Jeff Layton <jlayton@kernel.org>