On Mon, 2022-08-15 at 22:40 +0100, Al Viro wrote: > On Mon, Aug 15, 2022 at 05:26:20PM -0400, Rik van Riel wrote: > > TL;DR: it runs better than it looks, and I am looking for ideas on > > how to make it look better > > > Unfortunately there seems to be a tradeoff between temporarily > > allocating things on the stack, and having slightly uglier code, > > or adding a struct rcu_work to the struct vfsmount. > > > > I am not entirely happy with the way this code looks, and hoping > > for suggestions on how to improve it. > > > > IMO you are going in wrong direction with that; it's a long story, > and I've partial writeup on that, but I won't have it ready for > posting until the end of the week.  Put it that way - there's > a possibility of reorganizing the way mount refcounts work, > eliminating this synchronize_rcu().  RCU delay still has to happen > in some form, but we get smarter ways to wait for it. > I'm more than happy to abandon this approach. I looked at this a bunch, and could not find a nice way to do this the way the VFS currently works, and am looking forward to getting this done in a better way! -- All Rights Reversed.