On Thu, Jun 13, 2024 at 09:40:36AM -0600, Keith Busch wrote:
> On Thu, Jun 13, 2024 at 08:15:06AM -0700, Paul E. McKenney wrote:
> > On Thu, Jun 13, 2024 at 08:47:26AM -0600, Keith Busch wrote:
> > > >
> > > > Just make a helper function like this:
> > > >
> > > > static void my_synchronize_srcu(void)
> > > > {
> > > > synchronize_srcu(&my_srcu_struct);
> > > > }
> > > >
> > > > Or am I missing something subtle here?
> > >
> > > That would work if we had a global srcu, but the intended usage
> > > dynamically allocates one per device the driver is attached to, so a
> > > void callback doesn't know which one to sync.
> >
> > Ah, good point! I suppose that a further suggestion to just JIT the
> > needed function would not be well-received? ;-)
> >
> > I cannot resist suggesting placing a pointer to the srcu_struct in
> > the task structure. /me runs...
> >
> > Perhaps somewhat more constructively, my usual question: Is it really
> > necessary to have per-driver SRCU here? What would break if there was
> > a global srcu_struct that applied to all drivers?
>
> There's not a strict need for srcu_struct to be per device that I know
> of. It was just done this way to keep usage localized to the parts that
> need to be protected. The fear being that one device's long running
> reader could prevent another device from quickly tearing down.
That is a legitimate concern.
Is there a way to avoid this issue by making this be a statement parameter
to a macro?
Thanx, Paul
