On Wed, 2018-10-03 at 12:10 -0400, J . Bruce Fields wrote:
> The individual conversions of these caches looks straightforward to
> me.
> Thanks for doing this in these small steps. I'm assuming you're OK
> with
> these nfs/ changes going through the nfsd tree.
>
Yes please. With the bulk of the changes being nfsd specific, that
makes more sense to me.
> --b.
>
> On Mon, Oct 01, 2018 at 10:41:50AM -0400, Trond Myklebust wrote:
> > Enable RCU protected lookup in the legacy DNS resolver.
> >
> > Signed-off-by: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>
> > ---
> > fs/nfs/dns_resolve.c | 15 ++++++++++++---
> > 1 file changed, 12 insertions(+), 3 deletions(-)
> >
> > diff --git a/fs/nfs/dns_resolve.c b/fs/nfs/dns_resolve.c
> > index 060c658eab66..e93a5dc07c8c 100644
> > --- a/fs/nfs/dns_resolve.c
> > +++ b/fs/nfs/dns_resolve.c
> > @@ -65,6 +65,7 @@ struct nfs_dns_ent {
> >
> > struct sockaddr_storage addr;
> > size_t addrlen;
> > + struct rcu_head rcu_head;
> > };
> >
> >
> > @@ -101,15 +102,23 @@ static void nfs_dns_ent_init(struct
> > cache_head *cnew,
> > }
> > }
> >
> > -static void nfs_dns_ent_put(struct kref *ref)
> > +static void nfs_dns_ent_free_rcu(struct rcu_head *head)
> > {
> > struct nfs_dns_ent *item;
> >
> > - item = container_of(ref, struct nfs_dns_ent, h.ref);
> > + item = container_of(head, struct nfs_dns_ent, rcu_head);
> > kfree(item->hostname);
> > kfree(item);
> > }
> >
> > +static void nfs_dns_ent_put(struct kref *ref)
> > +{
> > + struct nfs_dns_ent *item;
> > +
> > + item = container_of(ref, struct nfs_dns_ent, h.ref);
> > + call_rcu(item, nfs_dns_ent_free_rcu);
> > +}
> > +
> > static struct cache_head *nfs_dns_ent_alloc(void)
> > {
> > struct nfs_dns_ent *item = kmalloc(sizeof(*item), GFP_KERNEL);
> > @@ -195,7 +204,7 @@ static struct nfs_dns_ent
> > *nfs_dns_lookup(struct cache_detail *cd,
> > {
> > struct cache_head *ch;
> >
> > - ch = sunrpc_cache_lookup(cd,
> > + ch = sunrpc_cache_lookup_rcu(cd,
> > &key->h,
> > nfs_dns_hash(key));
> > if (!ch)
> > --
> > 2.17.1
