On Sat, 2021-04-24 at 17:39 +0000, Chuck Lever III wrote:
>
>
> > On Apr 23, 2021, at 5:06 PM, Trond Myklebust <
> > trondmy@xxxxxxxxxxxxxxx> wrote:
> >
> > On Mon, 2021-04-19 at 14:02 -0400, Chuck Lever wrote:
> > > Currently rpcrdma_reps_destroy() assumes that, at transport
> > > tear-down, the content of the rb_free_reps list is the same as
> > > the
> > > content of the rb_all_reps list. Although that is usually true,
> > > using the rb_all_reps list should be more reliable because of
> > > the way it's managed. And, rpcrdma_reps_unmap() uses rb_all_reps;
> > > these two functions should both traverse the "all" list.
> > >
> > > Ensure that all rpcrdma_reps are always destroyed whether they
> > > are
> > > on the rep free list or not.
> > >
> > > Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx>
> > > ---
> > > net/sunrpc/xprtrdma/verbs.c | 31 ++++++++++++++++++++++++-----
> > > --
> > > 1 file changed, 24 insertions(+), 7 deletions(-)
> > >
> > > diff --git a/net/sunrpc/xprtrdma/verbs.c
> > > b/net/sunrpc/xprtrdma/verbs.c
> > > index 1b599a623eea..482fdc9e25c2 100644
> > > --- a/net/sunrpc/xprtrdma/verbs.c
> > > +++ b/net/sunrpc/xprtrdma/verbs.c
> > > @@ -1007,16 +1007,23 @@ struct rpcrdma_rep
> > > *rpcrdma_rep_create(struct
> > > rpcrdma_xprt *r_xprt,
> > > return NULL;
> > > }
> > >
> > > -/* No locking needed here. This function is invoked only by the
> > > - * Receive completion handler, or during transport shutdown.
> > > - */
> > > -static void rpcrdma_rep_destroy(struct rpcrdma_rep *rep)
> > > +static void rpcrdma_rep_destroy_locked(struct rpcrdma_rep *rep)
> >
> > The name here is extremely confusing. As far as I can tell, this
> > isn't
> > called with any lock?
>
> Fair enough.
>
> I renamed it rpcrdma_rep_free() and it doesn't seem to have
> any consequences for downstream commits in this series.
Sounds good.
>
> You could do a global edit, I can resend you this patch with
> the change, or I can post a v4 of this series. Let me know
> your preference.
>
Can you please just resend this patch with the update, unless there are
repercussions for the other patches? (in which case a v4 would be
welcome)
>
> > > {
> > > - list_del(&rep->rr_all);
> > > rpcrdma_regbuf_free(rep->rr_rdmabuf);
> > > kfree(rep);
> > > }
> > >
> > > +static void rpcrdma_rep_destroy(struct rpcrdma_rep *rep)
> > > +{
> > > + struct rpcrdma_buffer *buf = &rep->rr_rxprt->rx_buf;
> > > +
> > > + spin_lock(&buf->rb_lock);
> > > + list_del(&rep->rr_all);
> > > + spin_unlock(&buf->rb_lock);
> > > +
> > > + rpcrdma_rep_destroy_locked(rep);
> > > +}
> > > +
> > > static struct rpcrdma_rep *rpcrdma_rep_get_locked(struct
> > > rpcrdma_buffer *buf)
> > > {
> > > struct llist_node *node;
> > > @@ -1049,8 +1056,18 @@ static void rpcrdma_reps_destroy(struct
> > > rpcrdma_buffer *buf)
> > > {
> > > struct rpcrdma_rep *rep;
> > >
> > > - while ((rep = rpcrdma_rep_get_locked(buf)) != NULL)
> > > - rpcrdma_rep_destroy(rep);
> > > + spin_lock(&buf->rb_lock);
> > > + while ((rep = list_first_entry_or_null(&buf->rb_all_reps,
> > > + struct
> > > rpcrdma_rep,
> > > + rr_all)) != NULL)
> > > {
> > > + list_del(&rep->rr_all);
> > > + spin_unlock(&buf->rb_lock);
> > > +
> > > + rpcrdma_rep_destroy_locked(rep);
> > > +
> > > + spin_lock(&buf->rb_lock);
> > > + }
> > > + spin_unlock(&buf->rb_lock);
> > > }
> > >
> > > /**
> > >
> > >
> >
> > --
> > Trond Myklebust
> > Linux NFS client maintainer, Hammerspace
> > trond.myklebust@xxxxxxxxxxxxxxx
>
> --
> Chuck Lever
>
>
>
--
Trond Myklebust
Linux NFS client maintainer, Hammerspace
trond.myklebust@xxxxxxxxxxxxxxx
