These changes are the raw update to linux-4.4.6-rt14. Kernel sources

[kvmfornfv.git] / kernel / net / sched / act_gact.c

diff --git a/kernel/net/sched/act_gact.c b/kernel/net/sched/act_gact.c
index 7fffc22..5c1b051 100644 (file)
--- a/kernel/net/sched/act_gact.c
+++ b/kernel/net/sched/act_gact.c
@@ -28,14 +28,18 @@
 #ifdef CONFIG_GACT_PROB
 static int gact_net_rand(struct tcf_gact *gact)
 {
-       if (!gact->tcfg_pval || prandom_u32() % gact->tcfg_pval)
+       smp_rmb(); /* coupled with smp_wmb() in tcf_gact_init() */
+       if (prandom_u32() % gact->tcfg_pval)
                return gact->tcf_action;
        return gact->tcfg_paction;
 }
 
 static int gact_determ(struct tcf_gact *gact)
 {
-       if (!gact->tcfg_pval || gact->tcf_bstats.packets % gact->tcfg_pval)
+       u32 pack = atomic_inc_return(&gact->packets);
+
+       smp_rmb(); /* coupled with smp_wmb() in tcf_gact_init() */
+       if (pack % gact->tcfg_pval)
                return gact->tcf_action;
        return gact->tcfg_paction;
 }
@@ -85,7 +89,8 @@ static int tcf_gact_init(struct net *net, struct nlattr *nla,
 #endif
 
        if (!tcf_hash_check(parm->index, a, bind)) {
-               ret = tcf_hash_create(parm->index, est, a, sizeof(*gact), bind);
+               ret = tcf_hash_create(parm->index, est, a, sizeof(*gact),
+                                     bind, true);
                if (ret)
                        return ret;
                ret = ACT_P_CREATED;
@@ -99,16 +104,19 @@ static int tcf_gact_init(struct net *net, struct nlattr *nla,
 
        gact = to_gact(a);
 
-       spin_lock_bh(&gact->tcf_lock);
+       ASSERT_RTNL();
        gact->tcf_action = parm->action;
 #ifdef CONFIG_GACT_PROB
        if (p_parm) {
                gact->tcfg_paction = p_parm->paction;
-               gact->tcfg_pval    = p_parm->pval;
+               gact->tcfg_pval    = max_t(u16, 1, p_parm->pval);
+               /* Make sure tcfg_pval is written before tcfg_ptype
+                * coupled with smp_rmb() in gact_net_rand() & gact_determ()
+                */
+               smp_wmb();
                gact->tcfg_ptype   = p_parm->ptype;
        }
 #endif
-       spin_unlock_bh(&gact->tcf_lock);
        if (ret == ACT_P_CREATED)
                tcf_hash_insert(a);
        return ret;
@@ -118,23 +126,21 @@ static int tcf_gact(struct sk_buff *skb, const struct tc_action *a,
                    struct tcf_result *res)
 {
        struct tcf_gact *gact = a->priv;
-       int action = TC_ACT_SHOT;
+       int action = READ_ONCE(gact->tcf_action);
 
-       spin_lock(&gact->tcf_lock);
 #ifdef CONFIG_GACT_PROB
-       if (gact->tcfg_ptype)
-               action = gact_rand[gact->tcfg_ptype](gact);
-       else
-               action = gact->tcf_action;
-#else
-       action = gact->tcf_action;
+       {
+       u32 ptype = READ_ONCE(gact->tcfg_ptype);
+
+       if (ptype)
+               action = gact_rand[ptype](gact);
+       }
 #endif
-       gact->tcf_bstats.bytes += qdisc_pkt_len(skb);
-       gact->tcf_bstats.packets++;
+       bstats_cpu_update(this_cpu_ptr(gact->common.cpu_bstats), skb);
        if (action == TC_ACT_SHOT)
-               gact->tcf_qstats.drops++;
-       gact->tcf_tm.lastuse = jiffies;
-       spin_unlock(&gact->tcf_lock);
+               qstats_drop_inc(this_cpu_ptr(gact->common.cpu_qstats));
+
+       tcf_lastuse_update(&gact->tcf_tm);
 
        return action;
 }