Re: [PATCH v2 04/21] srcutree: Add an atomic Tree SRCU

[Paul E. McKenney]

On Mon, Oct 12, 2026 at 01:49:15PM +0100, David Woodhouse wrote:
> On Thu, 2026-10-08 at 08:51 -0700, Paul E. McKenney wrote:
> > On Thu, Oct 08, 2026 at 09:39:29AM +0200, David Woodhouse wrote:
> > > If it isn't already too late (i.e. if it hasn't already made it to a
> > > tree where changing commit-ids is painful), please could you change my
> > > attribution to use the dwmw@xxxxxxxxxxxx email address for both Co-
> > > developed-by: and Signed-off-by: tags? I'm fairly sure you made up that
> > > Signed-off-by: with the infradead address, which is naughty of you :)
> > 
> > Indeed, I would have grabbed the first email I could find from you and
> > applied the From: field from that email, as opposed to finding the exact
> > email containing your prototype of the patch and then locating and copying
> > out the Signed-off-by.  And if I were to happen to find the email that
> > I am now replying to, I would once again get infradead rather than amazon.
> > 
> > Apologies, but life was flowing fast, and it probably will be from time
> > to time in the future.  So thank you for checking and please continue
> > to do so.
> 
> Yeah, no problem. I do try to be good and give a SoB even when I'm
> throwing out a snippet of code that's *directional* and doesn't even
> compile. Mostly because I hate it when I'm on the receiving end of
> such, *use* the snippet I'm given, and then have to chase for a real
> SoB from a drive-by co-author.
> 
> In this case I think it was 
> https://lore.kernel.org/all/fb87f673bf290cad133d113dbb0750a7752b9d30.camel@xxxxxxxxxxxxx/
> which did have them both on the patch itself.
> 
> > > I tell people you should only ever cut-and-paste SoB lines, because
> > > that way the magic is intact. So here are the two you need for patches
> > > 4 and 5 of this series:
> > > 
> > > Signed-off-by: David Woodhouse <dwmw@xxxxxxxxxxxx>
> > > Signed-off-by: David Woodhouse <dwmw@xxxxxxxxxxxx>
> > 
> > Thank you again, and I have this note to myself for my next rebase:
> > 
> > a5130cf7b27f ("srcutree: Add an atomic Tree SRCU")
> > 85d5f89bdc42 ("srcutiny: Add an atomic Tiny SRCU")
> > 	Co-developed-by: David Woodhouse <dwmw@xxxxxxxxxxxx>
> > 	Signed-off-by: David Woodhouse <dwmw@xxxxxxxxxxxx>
> > 
> > Does that cover it?
> 
> Looks good, thanks!

And these are now applied in my -rcu tree:

60df507b6091 ("srcutree: Add an atomic Tree SRCU")
a48669f0c49c ("srcutiny: Add an atomic Tiny SRCU")

I intend to send the pull request before the merge window opens, so if
further adjustment is needed, please let me know right away.

> > And while we are discussing, how goes the use case?
> 
> It's working well. Torture tests and Sashiko reviews have tweaked it a
> bit, and found one issue that was already there in the upstream kernel.
> https://git.infradead.org/?p=users/dwmw2/linux.git;a=shortlog;h=refs/heads/gpc-srcu-v2
> 
> I've also backported it to a production tree (albeit using non-atomic
> SRCU there for now) and it works there too.
> 
> I still have to put my own eyes on some of those latest tweaks (and
> probably rewrite/decimate the commit messages). Will do so once the
> dust settles on the atomic-srcu work and I can rebase on top of a
> stable commit. But there's no rush; this whole thing has been on the
> back burner for a long time.

Here is hoping!  ;-)

							Thanx, Paul