On Thu, Feb 02, 2017 at 03:38:07PM +0100, Andreas Schultz wrote:
>
>
> ----- On Feb 2, 2017, at 3:28 PM, pablo pa...@netfilter.org wrote:
>
> > On Thu, Feb 02, 2017 at 03:12:55PM +0100, Andreas Schultz wrote:
> >> Hi,
> >>
> >> ----- On Feb 2, 2017, at 2:56 PM, pablo pa...@netfilter.org wrote:
> >>
> >> > On Mon, Jan 30, 2017 at 05:37:12PM +0100, Andreas Schultz wrote:
> >> >> Having the socket present in context simplifies the sending logic.
> >> >> It also fixes the invalid assumption that we have to use the same
> >> >> sending socket for all client IP's on a specific gtp interface.
> >> >>
> >> >> Signed-off-by: Andreas Schultz <aschu...@tpip.net>
> >> >> ---
> >> >> drivers/net/gtp.c | 72
> >> >> ++++++++++++++++++++++++++++++-------------------------
> >> >> 1 file changed, 39 insertions(+), 33 deletions(-)
> >> >>
> >> >> diff --git a/drivers/net/gtp.c b/drivers/net/gtp.c
> >> >> index 68c6c9b..ff00597 100644
> >> >> --- a/drivers/net/gtp.c
> >> >> +++ b/drivers/net/gtp.c
> >> > [...]
> >> >> @@ -984,16 +966,26 @@ static int ipv4_pdp_add(struct gtp_dev *gtp,
> >> >> struct
> >> >> genl_info *info)
> >> >> return 0;
> >> >> }
> >> >>
> >> >> +static void pdp_context_free(struct rcu_head *head)
> >> >> +{
> >> >> + struct pdp_ctx *pctx = container_of(head, struct pdp_ctx,
> >> >> rcu_head);
> >> >> +
> >> >> + sock_put(pctx->sk);
> >> >> + kfree(pctx);
> >> >> +}
> >> >> +
> >> >> static void pdp_context_delete(struct pdp_ctx *pctx)
> >> >> {
> >> >> hlist_del_rcu(&pctx->hlist_tid);
> >> >> hlist_del_rcu(&pctx->hlist_addr);
> >> >> - kfree(pctx);
> >> >> + call_rcu(&pctx->rcu_head, pdp_context_free);
> >> >
> >> > This is fixing incorrect rcu conversion in 4/6. Please, fix this there.
> >>
> >> Ehm, right, but the kfree in 4/6 could have been a kfree_rcu instead
> >> without
> >> the call_rcu.
> >>
> >> Do you prefer to introduce the call_rcu in 4/6 and then just add the
> >> sock_put
> >> in this patch or should I change 4/6 to kfree_rcu and do the call_rcu
> >> conversion here?
> >
> > I suggest you just call kfree_rcu() from 4/6.
> >
> > Regarding holding socket reference, see my comment for patch 1/6.
>
> This is going to be a problem at this stage of the changes.
>
> The final goal is to have a reference from the socket to the pdp context.
Is this just a cleanup? Or you need this sk caching for some follow up
work?
> Then, when the socket is closed, the pdp context can be destroyed.
>
> However, at this point, only the netdevice knows about the contexts. So
> when the socket is closed, the pdp context would have a dangling reference
> to the socket.
>
> I can integrate this change into the later one. But it will make that
> change larger and more difficult to review.
>
> I guess, I'm going to drop this change from this series and see if can
> reorder the next part so that it still makes and I easy to review....
Agreed. Thanks.
