--- zzzz-none-000/linux-3.10.107/net/sched/act_gact.c 2017-06-27 09:49:32.000000000 +0000 +++ scorpion-7490-727/linux-3.10.107/net/sched/act_gact.c 2021-02-04 17:41:59.000000000 +0000 @@ -1,5 +1,5 @@ /* - * net/sched/gact.c Generic actions + * net/sched/act_gact.c Generic actions * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License @@ -24,27 +24,22 @@ #include #define GACT_TAB_MASK 15 -static struct tcf_common *tcf_gact_ht[GACT_TAB_MASK + 1]; -static u32 gact_idx_gen; -static DEFINE_RWLOCK(gact_lock); - -static struct tcf_hashinfo gact_hash_info = { - .htab = tcf_gact_ht, - .hmask = GACT_TAB_MASK, - .lock = &gact_lock, -}; #ifdef CONFIG_GACT_PROB static int gact_net_rand(struct tcf_gact *gact) { - if (!gact->tcfg_pval || net_random() % 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; } @@ -65,7 +60,6 @@ struct nlattr *tb[TCA_GACT_MAX + 1]; struct tc_gact *parm; struct tcf_gact *gact; - struct tcf_common *pc; int ret = 0; int err; #ifdef CONFIG_GACT_PROB @@ -94,67 +88,59 @@ } #endif - pc = tcf_hash_check(parm->index, a, bind, &gact_hash_info); - if (!pc) { - pc = tcf_hash_create(parm->index, est, a, sizeof(*gact), - bind, &gact_idx_gen, &gact_hash_info); - if (IS_ERR(pc)) - return PTR_ERR(pc); + if (!tcf_hash_check(parm->index, a, bind)) { + ret = tcf_hash_create(parm->index, est, a, sizeof(*gact), + bind, true); + if (ret) + return ret; ret = ACT_P_CREATED; } else { - if (!ovr) { - tcf_hash_release(pc, bind, &gact_hash_info); + if (bind)/* dont override defaults */ + return 0; + tcf_hash_release(a, bind); + if (!ovr) return -EEXIST; - } } - gact = to_gact(pc); + 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(pc, &gact_hash_info); + tcf_hash_insert(a); return ret; } -static int tcf_gact_cleanup(struct tc_action *a, int bind) -{ - struct tcf_gact *gact = a->priv; - - if (gact) - return tcf_hash_release(&gact->common, bind, &gact_hash_info); - return 0; -} - 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; } @@ -199,16 +185,11 @@ static struct tc_action_ops act_gact_ops = { .kind = "gact", - .hinfo = &gact_hash_info, .type = TCA_ACT_GACT, - .capab = TCA_CAP_NONE, .owner = THIS_MODULE, .act = tcf_gact, .dump = tcf_gact_dump, - .cleanup = tcf_gact_cleanup, - .lookup = tcf_hash_search, .init = tcf_gact_init, - .walk = tcf_generic_walker }; MODULE_AUTHOR("Jamal Hadi Salim(2002-4)"); @@ -222,7 +203,7 @@ #else pr_info("GACT probability NOT on\n"); #endif - return tcf_register_action(&act_gact_ops); + return tcf_register_action(&act_gact_ops, GACT_TAB_MASK); } static void __exit gact_cleanup_module(void)