ebiederm-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org (Eric W. Biederman) writes:

Andy Lutomirski [off-list ref] writes:

quoted

This text was actually my suggested comment text.

Now I see.

quoted

If you put smp_rmb() in this function with a comment like that, then I
think it will all make sense and be obviously correct (even with most
of the other barriers removed).

Right.

Given that we have to be careful when using these things anyway what
I was hoping to achieve with the barriers appears impossible, and
confusing so I will see about just adding barriers where we need them
for real.  Sigh.

Doh.  The code has been entirely too clever.

There are no need for atomics or other cleverness, I just need to
generalize id_map_mutex.  I knew that had to be a trivially correct
way of handling this mess.

Eric