Re: [PATCH v3 net-next 13/14] af_unix: Replace garbage collection algorithm.

[Kuniyuki Iwashima <kuniyu@amazon.com>]

From: Paolo Abeni <pabeni@redhat.com>
Date: Wed, 28 Feb 2024 09:08:32 +0100
> On Tue, 2024-02-27 at 19:32 -0800, Kuniyuki Iwashima wrote:
> > From: Paolo Abeni <pabeni@redhat.com>
> > Date: Tue, 27 Feb 2024 12:36:51 +0100
> > > On Fri, 2024-02-23 at 13:40 -0800, Kuniyuki Iwashima wrote:
> > > > diff --git a/net/unix/garbage.c b/net/unix/garbage.c
> > > > index 060e81be3614..59a87a997a4d 100644
> > > > --- a/net/unix/garbage.c
> > > > +++ b/net/unix/garbage.c
> > > > @@ -314,6 +314,48 @@ static bool unix_vertex_dead(struct unix_vertex *vertex)
> > > >  	return true;
> > > >  }
> > > >  
> > > > +static struct sk_buff_head hitlist;
> > > 
> > > I *think* hitlist could be replaced with a local variable in
> > > __unix_gc(), WDYT?
> > 
> > Actually it was a local variable in the first draft.
> > 
> > In the current GC impl, hitlist is passed down to functions,
> > but only the leaf function uses it, and I thought the global
> > variable would be easier to follow.
> > 
> > And now __unix_gc() is not called twice at the same time thanks
> > to workqueue, and hitlist can be a global variable.
> 
> My personal preference would be for a local variable, unless it makes
> the code significant more complex: I think it's more clear and avoid
> possible false sharing issues in the data segment.

I didn't think of that point.
I'll use a local variable for hitlist.

Thanks!