Retry check-insert sequence in action init functions if action with same
index was inserted concurrently.

Signed-off-by: Vlad Buslov <redacted>
---
net/sched/act_bpf.c        | 8 +++++++-
net/sched/act_connmark.c   | 8 +++++++-
net/sched/act_csum.c       | 8 +++++++-
net/sched/act_gact.c       | 8 +++++++-
net/sched/act_ife.c        | 8 +++++++-
net/sched/act_ipt.c        | 8 +++++++-
net/sched/act_mirred.c     | 8 +++++++-
net/sched/act_nat.c        | 8 +++++++-
net/sched/act_pedit.c      | 8 +++++++-
net/sched/act_police.c     | 9 ++++++++-
net/sched/act_sample.c     | 8 +++++++-
net/sched/act_simple.c     | 9 ++++++++-
net/sched/act_skbedit.c    | 8 +++++++-
net/sched/act_skbmod.c     | 8 +++++++-
net/sched/act_tunnel_key.c | 9 ++++++++-
net/sched/act_vlan.c       | 9 ++++++++-
16 files changed, 116 insertions(+), 16 deletions(-)

diff --git a/net/sched/act_bpf.c b/net/sched/act_bpf.c
index 5554bf7..7e20fdc 100644
--- a/net/sched/act_bpf.c
+++ b/net/sched/act_bpf.c

@@ -299,10 +299,16 @@ static int tcf_bpf_init(struct net *net, struct nlattr *nla,

	parm = nla_data(tb[TCA_ACT_BPF_PARMS]);

+replay:
	if (!tcf_idr_check(tn, parm->index, act, bind)) {
		ret = tcf_idr_create(tn, parm->index, est, act,
				     &act_bpf_ops, bind, true);
-		if (ret < 0)
+		/* Action with specified index was created concurrently.
+		 * Check again.
+		 */
+		if (parm->index && ret == -ENOSPC)
+			goto replay;
+		else if (ret)