linux/net/sched/act_police.c

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/*
* net/sched/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 cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 08:04:11 +00:00
#include <linux/slab.h>
#include <net/act_api.h>
#include <net/netlink.h>
#define L2T(p,L) qdisc_l2t((p)->tcfp_R_tab, L)
#define L2T_P(p,L) qdisc_l2t((p)->tcfp_P_tab, L)
#define POL_TAB_MASK 15
static struct tcf_common *tcf_police_ht[POL_TAB_MASK + 1];
static u32 police_idx_gen;
static DEFINE_RWLOCK(police_lock);
static struct tcf_hashinfo police_hash_info = {
.htab = tcf_police_ht,
.hmask = POL_TAB_MASK,
.lock = &police_lock,
};
/* 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 int tcf_act_police_walker(struct sk_buff *skb, struct netlink_callback *cb,
int type, struct tc_action *a)
{
struct tcf_common *p;
int err = 0, index = -1, i = 0, s_i = 0, n_i = 0;
struct nlattr *nest;
read_lock_bh(&police_lock);
s_i = cb->args[0];
for (i = 0; i < (POL_TAB_MASK + 1); i++) {
p = tcf_police_ht[tcf_hash(i, POL_TAB_MASK)];
for (; p; p = p->tcfc_next) {
index++;
if (index < s_i)
continue;
a->priv = p;
a->order = index;
nest = nla_nest_start(skb, a->order);
if (nest == NULL)
goto nla_put_failure;
if (type == RTM_DELACTION)
err = tcf_action_dump_1(skb, a, 0, 1);
else
err = tcf_action_dump_1(skb, a, 0, 0);
if (err < 0) {
index--;
nla_nest_cancel(skb, nest);
goto done;
}
nla_nest_end(skb, nest);
n_i++;
}
}
done:
read_unlock_bh(&police_lock);
if (n_i)
cb->args[0] += n_i;
return n_i;
nla_put_failure:
nla_nest_cancel(skb, nest);
goto done;
}
static void tcf_police_free_rcu(struct rcu_head *head)
{
kfree(container_of(head, struct tcf_police, tcf_rcu));
}
static void tcf_police_destroy(struct tcf_police *p)
{
unsigned int h = tcf_hash(p->tcf_index, POL_TAB_MASK);
struct tcf_common **p1p;
for (p1p = &tcf_police_ht[h]; *p1p; p1p = &(*p1p)->tcfc_next) {
if (*p1p == &p->common) {
write_lock_bh(&police_lock);
*p1p = p->tcf_next;
write_unlock_bh(&police_lock);
gen_kill_estimator(&p->tcf_bstats,
&p->tcf_rate_est);
if (p->tcfp_R_tab)
qdisc_put_rtab(p->tcfp_R_tab);
if (p->tcfp_P_tab)
qdisc_put_rtab(p->tcfp_P_tab);
/*
* gen_estimator est_timer() might access p->tcf_lock
* or bstats, wait a RCU grace period before freeing p
*/
call_rcu(&p->tcf_rcu, tcf_police_free_rcu);
return;
}
}
WARN_ON(1);
}
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_locate(struct nlattr *nla, struct nlattr *est,
struct tc_action *a, int ovr, int bind)
{
unsigned h;
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;
int size;
if (nla == NULL)
return -EINVAL;
err = nla_parse_nested(tb, TCA_POLICE_MAX, nla, police_policy);
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]);
if (parm->index) {
struct tcf_common *pc;
pc = tcf_hash_lookup(parm->index, &police_hash_info);
if (pc != NULL) {
a->priv = pc;
police = to_police(pc);
if (bind) {
police->tcf_bindcnt += 1;
police->tcf_refcnt += 1;
}
if (ovr)
goto override;
return ret;
}
}
police = kzalloc(sizeof(*police), GFP_KERNEL);
if (police == NULL)
return -ENOMEM;
ret = ACT_P_CREATED;
police->tcf_refcnt = 1;
spin_lock_init(&police->tcf_lock);
if (bind)
police->tcf_bindcnt = 1;
override:
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;
}
}
spin_lock_bh(&police->tcf_lock);
if (est) {
err = gen_replace_estimator(&police->tcf_bstats,
&police->tcf_rate_est,
&police->tcf_lock, est);
if (err)
goto failure_unlock;
} else if (tb[TCA_POLICE_AVRATE] &&
(ret == ACT_P_CREATED ||
!gen_estimator_active(&police->tcf_bstats,
&police->tcf_rate_est))) {
err = -EINVAL;
goto failure_unlock;
}
/* No failure allowed after this point */
if (R_tab != NULL) {
qdisc_put_rtab(police->tcfp_R_tab);
police->tcfp_R_tab = R_tab;
}
if (P_tab != NULL) {
qdisc_put_rtab(police->tcfp_P_tab);
police->tcfp_P_tab = P_tab;
}
if (tb[TCA_POLICE_RESULT])
police->tcfp_result = nla_get_u32(tb[TCA_POLICE_RESULT]);
police->tcfp_toks = police->tcfp_burst = parm->burst;
police->tcfp_mtu = parm->mtu;
if (police->tcfp_mtu == 0) {
police->tcfp_mtu = ~0;
if (police->tcfp_R_tab)
police->tcfp_mtu = 255<<police->tcfp_R_tab->rate.cell_log;
}
if (police->tcfp_P_tab)
police->tcfp_ptoks = L2T_P(police, police->tcfp_mtu);
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 = psched_get_time();
police->tcf_index = parm->index ? parm->index :
tcf_hash_new_index(&police_idx_gen, &police_hash_info);
h = tcf_hash(police->tcf_index, POL_TAB_MASK);
write_lock_bh(&police_lock);
police->tcf_next = tcf_police_ht[h];
tcf_police_ht[h] = &police->common;
write_unlock_bh(&police_lock);
a->priv = police;
return ret;
failure_unlock:
spin_unlock_bh(&police->tcf_lock);
failure:
if (P_tab)
qdisc_put_rtab(P_tab);
if (R_tab)
qdisc_put_rtab(R_tab);
if (ret == ACT_P_CREATED)
kfree(police);
return err;
}
static int tcf_act_police_cleanup(struct tc_action *a, int bind)
{
struct tcf_police *p = a->priv;
int ret = 0;
if (p != NULL) {
if (bind)
p->tcf_bindcnt--;
p->tcf_refcnt--;
if (p->tcf_refcnt <= 0 && !p->tcf_bindcnt) {
tcf_police_destroy(p);
ret = 1;
}
}
return ret;
}
static int tcf_act_police(struct sk_buff *skb, struct tc_action *a,
struct tcf_result *res)
{
struct tcf_police *police = a->priv;
psched_time_t now;
long toks;
long ptoks = 0;
spin_lock(&police->tcf_lock);
bstats_update(&police->tcf_bstats, skb);
if (police->tcfp_ewma_rate &&
police->tcf_rate_est.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->tcfp_R_tab == NULL) {
spin_unlock(&police->tcf_lock);
return police->tcfp_result;
}
now = psched_get_time();
toks = psched_tdiff_bounded(now, police->tcfp_t_c,
police->tcfp_burst);
if (police->tcfp_P_tab) {
ptoks = toks + police->tcfp_ptoks;
if (ptoks > (long)L2T_P(police, police->tcfp_mtu))
ptoks = (long)L2T_P(police, police->tcfp_mtu);
ptoks -= L2T_P(police, qdisc_pkt_len(skb));
}
toks += police->tcfp_toks;
if (toks > (long)police->tcfp_burst)
toks = police->tcfp_burst;
toks -= L2T(police, qdisc_pkt_len(skb));
if ((toks|ptoks) >= 0) {
police->tcfp_t_c = now;
police->tcfp_toks = toks;
police->tcfp_ptoks = ptoks;
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 = a->priv;
struct tc_police opt = {
.index = police->tcf_index,
.action = police->tcf_action,
.mtu = police->tcfp_mtu,
.burst = police->tcfp_burst,
.refcnt = police->tcf_refcnt - ref,
.bindcnt = police->tcf_bindcnt - bind,
};
if (police->tcfp_R_tab)
opt.rate = police->tcfp_R_tab->rate;
if (police->tcfp_P_tab)
opt.peakrate = police->tcfp_P_tab->rate;
NLA_PUT(skb, TCA_POLICE_TBF, sizeof(opt), &opt);
if (police->tcfp_result)
NLA_PUT_U32(skb, TCA_POLICE_RESULT, police->tcfp_result);
if (police->tcfp_ewma_rate)
NLA_PUT_U32(skb, TCA_POLICE_AVRATE, police->tcfp_ewma_rate);
return skb->len;
nla_put_failure:
nlmsg_trim(skb, b);
return -1;
}
MODULE_AUTHOR("Alexey Kuznetsov");
MODULE_DESCRIPTION("Policing actions");
MODULE_LICENSE("GPL");
static struct tc_action_ops act_police_ops = {
.kind = "police",
.hinfo = &police_hash_info,
.type = TCA_ID_POLICE,
.capab = TCA_CAP_NONE,
.owner = THIS_MODULE,
.act = tcf_act_police,
.dump = tcf_act_police_dump,
.cleanup = tcf_act_police_cleanup,
.lookup = tcf_hash_search,
.init = tcf_act_police_locate,
.walk = tcf_act_police_walker
};
static int __init
police_init_module(void)
{
return tcf_register_action(&act_police_ops);
}
static void __exit
police_cleanup_module(void)
{
tcf_unregister_action(&act_police_ops);
rcu_barrier(); /* Wait for completion of call_rcu()'s (tcf_police_free_rcu) */
}
module_init(police_init_module);
module_exit(police_cleanup_module);