On Tue, Aug 08, 2017 at 09:16:33PM +0800, Gao Feng wrote:
> At 2017-08-08 17:43:24, "Guillaume Nault" <g.na...@alphalink.fr> wrote:
> >--- a/drivers/net/ppp/ppp_generic.c
> >+++ b/drivers/net/ppp/ppp_generic.c
> >@@ -1915,21 +1915,23 @@ static void __ppp_channel_push(struct channel *pch)
> > spin_unlock(&pch->downl);
> > /* see if there is anything from the attached unit to be sent */
> > if (skb_queue_empty(&pch->file.xq)) {
> >- read_lock(&pch->upl);
> > ppp = pch->ppp;
> > if (ppp)
> >- ppp_xmit_process(ppp);
> >- read_unlock(&pch->upl);
> >+ __ppp_xmit_process(ppp);
> > }
> > }
> >
> > static void ppp_channel_push(struct channel *pch)
> > {
> >- local_bh_disable();
> >-
> >- __ppp_channel_push(pch);
> >-
> >- local_bh_enable();
> >+ read_lock_bh(&pch->upl);
> >+ if (pch->ppp) {
> >+ (*this_cpu_ptr(pch->ppp->xmit_recursion))++;
> >+ __ppp_channel_push(pch);
> >+ (*this_cpu_ptr(pch->ppp->xmit_recursion))--;
> >+ } else {
> >+ __ppp_channel_push(pch);
> >+ }
> >+ read_unlock_bh(&pch->upl);
>
> If invoked read_lock_bh in ppp_channel_push, it would be unnecessary to
> invoke read_lock(&pch->upl)
> in the __ppp_channel_push.
>
But this patch does remove read_lock(&pch->upl) from
__ppp_channel_push(). Or have I misunderstood your point?