On Tue, Aug 29, 2017 at 03:25:35AM +0000, Chris Mi wrote: > > > > -----Original Message----- > > From: Simon Horman [mailto:simon.hor...@netronome.com] > > Sent: Monday, August 28, 2017 7:37 PM > > To: Chris Mi <chr...@mellanox.com> > > Cc: netdev@vger.kernel.org; j...@mojatatu.com; > > xiyou.wangc...@gmail.com; j...@resnulli.us; da...@davemloft.net; > > mawil...@microsoft.com > > Subject: Re: [patch net-next 2/3] net/sched: Change cls_flower to use IDR > > > > On Mon, Aug 28, 2017 at 02:41:16AM -0400, Chris Mi wrote: > > > Currently, all filters with the same priority are linked in a doubly > > > linked list. Every filter should have a unique handle. To make the > > > handle unique, we need to iterate the list every time to see if the > > > handle exists or not when inserting a new filter. It is time-consuming. > > > For example, it takes about 5m3.169s to insert 64K rules. > > > > > > This patch changes cls_flower to use IDR. With this patch, it takes > > > about 0m1.127s to insert 64K rules. The improvement is huge. > > > > Very nice :) > > > > > But please note that in this testing, all filters share the same action. > > > If every filter has a unique action, that is another bottleneck. > > > Follow-up patch in this patchset addresses that. > > > > > > Signed-off-by: Chris Mi <chr...@mellanox.com> > > > Signed-off-by: Jiri Pirko <j...@mellanox.com> > > > --- > > > net/sched/cls_flower.c | 55 > > > +++++++++++++++++++++----------------------------- > > > 1 file changed, 23 insertions(+), 32 deletions(-) > > > > > > diff --git a/net/sched/cls_flower.c b/net/sched/cls_flower.c index > > > bd9dab4..3d041d2 100644 > > > --- a/net/sched/cls_flower.c > > > +++ b/net/sched/cls_flower.c > > > > ... > > > > > @@ -890,6 +870,7 @@ static int fl_change(struct net *net, struct sk_buff > > *in_skb, > > > struct cls_fl_filter *fnew; > > > struct nlattr **tb; > > > struct fl_flow_mask mask = {}; > > > + unsigned long idr_index; > > > int err; > > > > > > if (!tca[TCA_OPTIONS]) > > > @@ -920,13 +901,21 @@ static int fl_change(struct net *net, struct sk_buff > > *in_skb, > > > goto errout; > > > > > > if (!handle) { > > > - handle = fl_grab_new_handle(tp, head); > > > - if (!handle) { > > > - err = -EINVAL; > > > + err = idr_alloc_ext(&head->handle_idr, fnew, &idr_index, > > > + 1, 0x80000000, GFP_KERNEL); > > > + if (err) > > > goto errout; > > > - } > > > + fnew->handle = idr_index; > > > + } > > > + > > > + /* user specifies a handle and it doesn't exist */ > > > + if (handle && !fold) { > > > + err = idr_alloc_ext(&head->handle_idr, fnew, &idr_index, > > > + handle, handle + 1, GFP_KERNEL); > > > + if (err) > > > + goto errout; > > > + fnew->handle = idr_index; > > > } > > > - fnew->handle = handle; > > > > > > if (tb[TCA_FLOWER_FLAGS]) { > > > fnew->flags = nla_get_u32(tb[TCA_FLOWER_FLAGS]); > > > @@ -980,6 +969,8 @@ static int fl_change(struct net *net, struct sk_buff > > *in_skb, > > > *arg = fnew; > > > > > > if (fold) { > > > + fnew->handle = handle; > > > > Can it be the case that fold is non-NULL and handle is zero? > > The handling of that case seem to have changed in this patch. > I don't think that could happen. In function tc_ctl_tfilter(), > > fl_get() will be called. If handle is zero, fl_get() will return NULL. > That means fold is NULL.
Thanks for the explanation, I see that now. > > > + idr_replace_ext(&head->handle_idr, fnew, fnew->handle); > > > list_replace_rcu(&fold->list, &fnew->list); > > > tcf_unbind_filter(tp, &fold->res); > > > call_rcu(&fold->rcu, fl_destroy_filter);
