mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-23 04:17:58 +07:00
74030603df
Laura reported a sleep-in-atomic kernel warning inside tcf_act_police_init() which calls gen_replace_estimator() with spinlock protection. It is not necessary in this case, we already have RTNL lock here so it is enough to protect concurrent writers. For the reader, i.e. tcf_act_police(), it needs to make decision based on this rate estimator, in the worst case we drop more/less packets than necessary while changing the rate in parallel, it is still acceptable. Reported-by: Laura Abbott <labbott@redhat.com> Reported-by: Nick Huber <nicholashuber@gmail.com> Cc: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
365 lines
9.3 KiB
C
365 lines
9.3 KiB
C
/*
|
|
* net/sched/act_police.c Input police filter
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public License
|
|
* as published by the Free Software Foundation; either version
|
|
* 2 of the License, or (at your option) any later version.
|
|
*
|
|
* Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
|
|
* J Hadi Salim (action changes)
|
|
*/
|
|
|
|
#include <linux/module.h>
|
|
#include <linux/types.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/string.h>
|
|
#include <linux/errno.h>
|
|
#include <linux/skbuff.h>
|
|
#include <linux/rtnetlink.h>
|
|
#include <linux/init.h>
|
|
#include <linux/slab.h>
|
|
#include <net/act_api.h>
|
|
#include <net/netlink.h>
|
|
|
|
struct tcf_police {
|
|
struct tc_action common;
|
|
int tcfp_result;
|
|
u32 tcfp_ewma_rate;
|
|
s64 tcfp_burst;
|
|
u32 tcfp_mtu;
|
|
s64 tcfp_toks;
|
|
s64 tcfp_ptoks;
|
|
s64 tcfp_mtu_ptoks;
|
|
s64 tcfp_t_c;
|
|
struct psched_ratecfg rate;
|
|
bool rate_present;
|
|
struct psched_ratecfg peak;
|
|
bool peak_present;
|
|
};
|
|
|
|
#define to_police(pc) ((struct tcf_police *)pc)
|
|
|
|
#define POL_TAB_MASK 15
|
|
|
|
/* old policer structure from before tc actions */
|
|
struct tc_police_compat {
|
|
u32 index;
|
|
int action;
|
|
u32 limit;
|
|
u32 burst;
|
|
u32 mtu;
|
|
struct tc_ratespec rate;
|
|
struct tc_ratespec peakrate;
|
|
};
|
|
|
|
/* Each policer is serialized by its individual spinlock */
|
|
|
|
static unsigned int police_net_id;
|
|
static struct tc_action_ops act_police_ops;
|
|
|
|
static int tcf_act_police_walker(struct net *net, struct sk_buff *skb,
|
|
struct netlink_callback *cb, int type,
|
|
const struct tc_action_ops *ops)
|
|
{
|
|
struct tc_action_net *tn = net_generic(net, police_net_id);
|
|
|
|
return tcf_generic_walker(tn, skb, cb, type, ops);
|
|
}
|
|
|
|
static const struct nla_policy police_policy[TCA_POLICE_MAX + 1] = {
|
|
[TCA_POLICE_RATE] = { .len = TC_RTAB_SIZE },
|
|
[TCA_POLICE_PEAKRATE] = { .len = TC_RTAB_SIZE },
|
|
[TCA_POLICE_AVRATE] = { .type = NLA_U32 },
|
|
[TCA_POLICE_RESULT] = { .type = NLA_U32 },
|
|
};
|
|
|
|
static int tcf_act_police_init(struct net *net, struct nlattr *nla,
|
|
struct nlattr *est, struct tc_action **a,
|
|
int ovr, int bind)
|
|
{
|
|
int ret = 0, err;
|
|
struct nlattr *tb[TCA_POLICE_MAX + 1];
|
|
struct tc_police *parm;
|
|
struct tcf_police *police;
|
|
struct qdisc_rate_table *R_tab = NULL, *P_tab = NULL;
|
|
struct tc_action_net *tn = net_generic(net, police_net_id);
|
|
bool exists = false;
|
|
int size;
|
|
|
|
if (nla == NULL)
|
|
return -EINVAL;
|
|
|
|
err = nla_parse_nested(tb, TCA_POLICE_MAX, nla, police_policy, NULL);
|
|
if (err < 0)
|
|
return err;
|
|
|
|
if (tb[TCA_POLICE_TBF] == NULL)
|
|
return -EINVAL;
|
|
size = nla_len(tb[TCA_POLICE_TBF]);
|
|
if (size != sizeof(*parm) && size != sizeof(struct tc_police_compat))
|
|
return -EINVAL;
|
|
|
|
parm = nla_data(tb[TCA_POLICE_TBF]);
|
|
exists = tcf_hash_check(tn, parm->index, a, bind);
|
|
if (exists && bind)
|
|
return 0;
|
|
|
|
if (!exists) {
|
|
ret = tcf_hash_create(tn, parm->index, NULL, a,
|
|
&act_police_ops, bind, false);
|
|
if (ret)
|
|
return ret;
|
|
ret = ACT_P_CREATED;
|
|
} else {
|
|
tcf_hash_release(*a, bind);
|
|
if (!ovr)
|
|
return -EEXIST;
|
|
}
|
|
|
|
police = to_police(*a);
|
|
if (parm->rate.rate) {
|
|
err = -ENOMEM;
|
|
R_tab = qdisc_get_rtab(&parm->rate, tb[TCA_POLICE_RATE]);
|
|
if (R_tab == NULL)
|
|
goto failure;
|
|
|
|
if (parm->peakrate.rate) {
|
|
P_tab = qdisc_get_rtab(&parm->peakrate,
|
|
tb[TCA_POLICE_PEAKRATE]);
|
|
if (P_tab == NULL)
|
|
goto failure;
|
|
}
|
|
}
|
|
|
|
if (est) {
|
|
err = gen_replace_estimator(&police->tcf_bstats, NULL,
|
|
&police->tcf_rate_est,
|
|
&police->tcf_lock,
|
|
NULL, est);
|
|
if (err)
|
|
goto failure;
|
|
} else if (tb[TCA_POLICE_AVRATE] &&
|
|
(ret == ACT_P_CREATED ||
|
|
!gen_estimator_active(&police->tcf_rate_est))) {
|
|
err = -EINVAL;
|
|
goto failure;
|
|
}
|
|
|
|
spin_lock_bh(&police->tcf_lock);
|
|
/* No failure allowed after this point */
|
|
police->tcfp_mtu = parm->mtu;
|
|
if (police->tcfp_mtu == 0) {
|
|
police->tcfp_mtu = ~0;
|
|
if (R_tab)
|
|
police->tcfp_mtu = 255 << R_tab->rate.cell_log;
|
|
}
|
|
if (R_tab) {
|
|
police->rate_present = true;
|
|
psched_ratecfg_precompute(&police->rate, &R_tab->rate, 0);
|
|
qdisc_put_rtab(R_tab);
|
|
} else {
|
|
police->rate_present = false;
|
|
}
|
|
if (P_tab) {
|
|
police->peak_present = true;
|
|
psched_ratecfg_precompute(&police->peak, &P_tab->rate, 0);
|
|
qdisc_put_rtab(P_tab);
|
|
} else {
|
|
police->peak_present = false;
|
|
}
|
|
|
|
if (tb[TCA_POLICE_RESULT])
|
|
police->tcfp_result = nla_get_u32(tb[TCA_POLICE_RESULT]);
|
|
police->tcfp_burst = PSCHED_TICKS2NS(parm->burst);
|
|
police->tcfp_toks = police->tcfp_burst;
|
|
if (police->peak_present) {
|
|
police->tcfp_mtu_ptoks = (s64) psched_l2t_ns(&police->peak,
|
|
police->tcfp_mtu);
|
|
police->tcfp_ptoks = police->tcfp_mtu_ptoks;
|
|
}
|
|
police->tcf_action = parm->action;
|
|
|
|
if (tb[TCA_POLICE_AVRATE])
|
|
police->tcfp_ewma_rate = nla_get_u32(tb[TCA_POLICE_AVRATE]);
|
|
|
|
spin_unlock_bh(&police->tcf_lock);
|
|
if (ret != ACT_P_CREATED)
|
|
return ret;
|
|
|
|
police->tcfp_t_c = ktime_get_ns();
|
|
tcf_hash_insert(tn, *a);
|
|
|
|
return ret;
|
|
|
|
failure:
|
|
qdisc_put_rtab(P_tab);
|
|
qdisc_put_rtab(R_tab);
|
|
if (ret == ACT_P_CREATED)
|
|
tcf_hash_cleanup(*a, est);
|
|
return err;
|
|
}
|
|
|
|
static int tcf_act_police(struct sk_buff *skb, const struct tc_action *a,
|
|
struct tcf_result *res)
|
|
{
|
|
struct tcf_police *police = to_police(a);
|
|
s64 now;
|
|
s64 toks;
|
|
s64 ptoks = 0;
|
|
|
|
spin_lock(&police->tcf_lock);
|
|
|
|
bstats_update(&police->tcf_bstats, skb);
|
|
tcf_lastuse_update(&police->tcf_tm);
|
|
|
|
if (police->tcfp_ewma_rate) {
|
|
struct gnet_stats_rate_est64 sample;
|
|
|
|
if (!gen_estimator_read(&police->tcf_rate_est, &sample) ||
|
|
sample.bps >= police->tcfp_ewma_rate) {
|
|
police->tcf_qstats.overlimits++;
|
|
if (police->tcf_action == TC_ACT_SHOT)
|
|
police->tcf_qstats.drops++;
|
|
spin_unlock(&police->tcf_lock);
|
|
return police->tcf_action;
|
|
}
|
|
}
|
|
|
|
if (qdisc_pkt_len(skb) <= police->tcfp_mtu) {
|
|
if (!police->rate_present) {
|
|
spin_unlock(&police->tcf_lock);
|
|
return police->tcfp_result;
|
|
}
|
|
|
|
now = ktime_get_ns();
|
|
toks = min_t(s64, now - police->tcfp_t_c,
|
|
police->tcfp_burst);
|
|
if (police->peak_present) {
|
|
ptoks = toks + police->tcfp_ptoks;
|
|
if (ptoks > police->tcfp_mtu_ptoks)
|
|
ptoks = police->tcfp_mtu_ptoks;
|
|
ptoks -= (s64) psched_l2t_ns(&police->peak,
|
|
qdisc_pkt_len(skb));
|
|
}
|
|
toks += police->tcfp_toks;
|
|
if (toks > police->tcfp_burst)
|
|
toks = police->tcfp_burst;
|
|
toks -= (s64) psched_l2t_ns(&police->rate, qdisc_pkt_len(skb));
|
|
if ((toks|ptoks) >= 0) {
|
|
police->tcfp_t_c = now;
|
|
police->tcfp_toks = toks;
|
|
police->tcfp_ptoks = ptoks;
|
|
if (police->tcfp_result == TC_ACT_SHOT)
|
|
police->tcf_qstats.drops++;
|
|
spin_unlock(&police->tcf_lock);
|
|
return police->tcfp_result;
|
|
}
|
|
}
|
|
|
|
police->tcf_qstats.overlimits++;
|
|
if (police->tcf_action == TC_ACT_SHOT)
|
|
police->tcf_qstats.drops++;
|
|
spin_unlock(&police->tcf_lock);
|
|
return police->tcf_action;
|
|
}
|
|
|
|
static int tcf_act_police_dump(struct sk_buff *skb, struct tc_action *a,
|
|
int bind, int ref)
|
|
{
|
|
unsigned char *b = skb_tail_pointer(skb);
|
|
struct tcf_police *police = to_police(a);
|
|
struct tc_police opt = {
|
|
.index = police->tcf_index,
|
|
.action = police->tcf_action,
|
|
.mtu = police->tcfp_mtu,
|
|
.burst = PSCHED_NS2TICKS(police->tcfp_burst),
|
|
.refcnt = police->tcf_refcnt - ref,
|
|
.bindcnt = police->tcf_bindcnt - bind,
|
|
};
|
|
struct tcf_t t;
|
|
|
|
if (police->rate_present)
|
|
psched_ratecfg_getrate(&opt.rate, &police->rate);
|
|
if (police->peak_present)
|
|
psched_ratecfg_getrate(&opt.peakrate, &police->peak);
|
|
if (nla_put(skb, TCA_POLICE_TBF, sizeof(opt), &opt))
|
|
goto nla_put_failure;
|
|
if (police->tcfp_result &&
|
|
nla_put_u32(skb, TCA_POLICE_RESULT, police->tcfp_result))
|
|
goto nla_put_failure;
|
|
if (police->tcfp_ewma_rate &&
|
|
nla_put_u32(skb, TCA_POLICE_AVRATE, police->tcfp_ewma_rate))
|
|
goto nla_put_failure;
|
|
|
|
t.install = jiffies_to_clock_t(jiffies - police->tcf_tm.install);
|
|
t.lastuse = jiffies_to_clock_t(jiffies - police->tcf_tm.lastuse);
|
|
t.firstuse = jiffies_to_clock_t(jiffies - police->tcf_tm.firstuse);
|
|
t.expires = jiffies_to_clock_t(police->tcf_tm.expires);
|
|
if (nla_put_64bit(skb, TCA_POLICE_TM, sizeof(t), &t, TCA_POLICE_PAD))
|
|
goto nla_put_failure;
|
|
|
|
return skb->len;
|
|
|
|
nla_put_failure:
|
|
nlmsg_trim(skb, b);
|
|
return -1;
|
|
}
|
|
|
|
static int tcf_police_search(struct net *net, struct tc_action **a, u32 index)
|
|
{
|
|
struct tc_action_net *tn = net_generic(net, police_net_id);
|
|
|
|
return tcf_hash_search(tn, a, index);
|
|
}
|
|
|
|
MODULE_AUTHOR("Alexey Kuznetsov");
|
|
MODULE_DESCRIPTION("Policing actions");
|
|
MODULE_LICENSE("GPL");
|
|
|
|
static struct tc_action_ops act_police_ops = {
|
|
.kind = "police",
|
|
.type = TCA_ID_POLICE,
|
|
.owner = THIS_MODULE,
|
|
.act = tcf_act_police,
|
|
.dump = tcf_act_police_dump,
|
|
.init = tcf_act_police_init,
|
|
.walk = tcf_act_police_walker,
|
|
.lookup = tcf_police_search,
|
|
.size = sizeof(struct tcf_police),
|
|
};
|
|
|
|
static __net_init int police_init_net(struct net *net)
|
|
{
|
|
struct tc_action_net *tn = net_generic(net, police_net_id);
|
|
|
|
return tc_action_net_init(tn, &act_police_ops, POL_TAB_MASK);
|
|
}
|
|
|
|
static void __net_exit police_exit_net(struct net *net)
|
|
{
|
|
struct tc_action_net *tn = net_generic(net, police_net_id);
|
|
|
|
tc_action_net_exit(tn);
|
|
}
|
|
|
|
static struct pernet_operations police_net_ops = {
|
|
.init = police_init_net,
|
|
.exit = police_exit_net,
|
|
.id = &police_net_id,
|
|
.size = sizeof(struct tc_action_net),
|
|
};
|
|
|
|
static int __init police_init_module(void)
|
|
{
|
|
return tcf_register_action(&act_police_ops, &police_net_ops);
|
|
}
|
|
|
|
static void __exit police_cleanup_module(void)
|
|
{
|
|
tcf_unregister_action(&act_police_ops, &police_net_ops);
|
|
}
|
|
|
|
module_init(police_init_module);
|
|
module_exit(police_cleanup_module);
|