RE: [EXT] Re: [v4,net-next 1/4] net: qos: introduce a gate control flow action

[Po Liu <po.liu@nxp.com>]

Hi Vlad,

> -----Original Message-----
> From: Vlad Buslov <vlad@buslov.dev>
> Sent: 2020年4月30日 1:04
> To: Po Liu <po.liu@nxp.com>
> Cc: davem@davemloft.net; linux-kernel@vger.kernel.org;
> netdev@vger.kernel.org; vinicius.gomes@intel.com; Claudiu Manoil
> <claudiu.manoil@nxp.com>; Vladimir Oltean <vladimir.oltean@nxp.com>;
> Alexandru Marginean <alexandru.marginean@nxp.com>;
> michael.chan@broadcom.com; vishal@chelsio.com;
> saeedm@mellanox.com; leon@kernel.org; jiri@mellanox.com;
> idosch@mellanox.com; alexandre.belloni@bootlin.com;
> UNGLinuxDriver@microchip.com; kuba@kernel.org; jhs@mojatatu.com;
> xiyou.wangcong@gmail.com; simon.horman@netronome.com;
> pablo@netfilter.org; moshe@mellanox.com; m-karicheri2@ti.com;
> andre.guedes@linux.intel.com; stephen@networkplumber.org
> Subject: [EXT] Re: [v4,net-next 1/4] net: qos: introduce a gate control flow
> action
> 
> Caution: EXT Email
> 
> Hi Po,
> 
> On Tue 28 Apr 2020 at 06:34, Po Liu <Po.Liu@nxp.com> wrote:
> > Introduce a ingress frame gate control flow action.
> > Tc gate action does the work like this:
> > Assume there is a gate allow specified ingress frames can be passed at
> > specific time slot, and be dropped at specific time slot. Tc filter
> > chooses the ingress frames, and tc gate action would specify what slot
> > does these frames can be passed to device and what time slot would be
> > dropped.
> > Tc gate action would provide an entry list to tell how much time gate
> > keep open and how much time gate keep state close. Gate action also
> > assign a start time to tell when the entry list start. Then driver
> > would repeat the gate entry list cyclically.
> > For the software simulation, gate action requires the user assign a
> > time clock type.
> >
> > Below is the setting example in user space. Tc filter a stream source
> > ip address is 192.168.0.20 and gate action own two time slots. One is
> > last 200ms gate open let frame pass another is last 100ms gate close
> > let frames dropped. When the ingress frames have reach total frames
> > over
> > 8000000 bytes, the excessive frames will be dropped in that
> > 200000000ns time slot.
> >
> >> tc qdisc add dev eth0 ingress
> >
> >> tc filter add dev eth0 parent ffff: protocol ip \
> >          flower src_ip 192.168.0.20 \
> >          action gate index 2 clockid CLOCK_TAI \
> >          sched-entry open 200000000 -1 8000000 \
> >          sched-entry close 100000000 -1 -1
> >
> >> tc chain del dev eth0 ingress chain 0
> >
> > "sched-entry" follow the name taprio style. Gate state is
> > "open"/"close". Follow with period nanosecond. Then next item is
> > internal priority value means which ingress queue should put. "-1"
> > means wildcard. The last value optional specifies the maximum number
> > of MSDU octets that are permitted to pass the gate during the
> > specified time interval.
> > Base-time is not set will be 0 as default, as result start time would
> > be ((N + 1) * cycletime) which is the minimal of future time.
> >
> > Below example shows filtering a stream with destination mac address is
> > 10:00:80:00:00:00 and ip type is ICMP, follow the action gate. The
> > gate action would run with one close time slot which means always keep
> close.
> > The time cycle is total 200000000ns. The base-time would calculate by:
> >
> >  1357000000000 + (N + 1) * cycletime
> >
> > When the total value is the future time, it will be the start time.
> > The cycletime here would be 200000000ns for this case.
> >
> >> tc filter add dev eth0 parent ffff:  protocol ip \
> >          flower skip_hw ip_proto icmp dst_mac 10:00:80:00:00:00 \
> >          action gate index 12 base-time 1357000000000 \
> >          sched-entry close 200000000 -1 -1 \
> >          clockid CLOCK_TAI
> >
> > Signed-off-by: Po Liu <Po.Liu@nxp.com>
> > ---
> >  include/net/tc_act/tc_gate.h        |  47 ++
> >  include/uapi/linux/pkt_cls.h        |   1 +
> >  include/uapi/linux/tc_act/tc_gate.h |  47 ++
> >  net/sched/Kconfig                   |  12 +
> >  net/sched/Makefile                  |   1 +
> >  net/sched/act_gate.c                | 638 ++++++++++++++++++++++++++++
> >  6 files changed, 746 insertions(+)
> >  create mode 100644 include/net/tc_act/tc_gate.h  create mode 100644
> > include/uapi/linux/tc_act/tc_gate.h
> >  create mode 100644 net/sched/act_gate.c
> >
> > diff --git a/include/net/tc_act/tc_gate.h
> > b/include/net/tc_act/tc_gate.h new file mode 100644 index
> > 000000000000..330ad8b02495
> > --- /dev/null
> > +++ b/include/net/tc_act/tc_gate.h
> > @@ -0,0 +1,47 @@
> > +/* SPDX-License-Identifier: GPL-2.0-or-later */
> > +/* Copyright 2020 NXP */
> > +
> > +#ifndef __NET_TC_GATE_H
> > +#define __NET_TC_GATE_H
> > +
> > +#include <net/act_api.h>
> > +#include <linux/tc_act/tc_gate.h>
> > +
> > +struct tcfg_gate_entry {
> > +     int                     index;
> > +     u8                      gate_state;
> > +     u32                     interval;
> > +     s32                     ipv;
> > +     s32                     maxoctets;
> > +     struct list_head        list;
> > +};
> > +
> > +struct tcf_gate_params {
> > +     s32                     tcfg_priority;
> > +     u64                     tcfg_basetime;
> > +     u64                     tcfg_cycletime;
> > +     u64                     tcfg_cycletime_ext;
> > +     u32                     tcfg_flags;
> > +     s32                     tcfg_clockid;
> > +     size_t                  num_entries;
> > +     struct list_head        entries;
> > +};
> > +
> > +#define GATE_ACT_GATE_OPEN   BIT(0)
> > +#define GATE_ACT_PENDING     BIT(1)
> > +
> > +struct tcf_gate {
> > +     struct tc_action        common;
> > +     struct tcf_gate_params  param;
> > +     u8                      current_gate_status;
> > +     ktime_t                 current_close_time;
> > +     u32                     current_entry_octets;
> > +     s32                     current_max_octets;
> > +     struct tcfg_gate_entry  *next_entry;
> > +     struct hrtimer          hitimer;
> > +     enum tk_offsets         tk_offset;
> > +};
> > +
> > +#define to_gate(a) ((struct tcf_gate *)a)
> > +
> > +#endif
> > diff --git a/include/uapi/linux/pkt_cls.h
> > b/include/uapi/linux/pkt_cls.h index 9f06d29cab70..fc672b232437
> 100644
> > --- a/include/uapi/linux/pkt_cls.h
> > +++ b/include/uapi/linux/pkt_cls.h
> > @@ -134,6 +134,7 @@ enum tca_id {
> >       TCA_ID_CTINFO,
> >       TCA_ID_MPLS,
> >       TCA_ID_CT,
> > +     TCA_ID_GATE,
> >       /* other actions go here */
> >       __TCA_ID_MAX = 255
> >  };
> > diff --git a/include/uapi/linux/tc_act/tc_gate.h
> > b/include/uapi/linux/tc_act/tc_gate.h
> > new file mode 100644
> > index 000000000000..f214b3a6d44f
> > --- /dev/null
> > +++ b/include/uapi/linux/tc_act/tc_gate.h
> > @@ -0,0 +1,47 @@
> > +/* SPDX-License-Identifier: GPL-2.0+ WITH Linux-syscall-note */
> > +/* Copyright 2020 NXP */
> > +
> > +#ifndef __LINUX_TC_GATE_H
> > +#define __LINUX_TC_GATE_H
> > +
> > +#include <linux/pkt_cls.h>
> > +
> > +struct tc_gate {
> > +     tc_gen;
> > +};
> > +
> > +enum {
> > +     TCA_GATE_ENTRY_UNSPEC,
> > +     TCA_GATE_ENTRY_INDEX,
> > +     TCA_GATE_ENTRY_GATE,
> > +     TCA_GATE_ENTRY_INTERVAL,
> > +     TCA_GATE_ENTRY_IPV,
> > +     TCA_GATE_ENTRY_MAX_OCTETS,
> > +     __TCA_GATE_ENTRY_MAX,
> > +};
> > +#define TCA_GATE_ENTRY_MAX (__TCA_GATE_ENTRY_MAX - 1)
> > +
> > +enum {
> > +     TCA_GATE_ONE_ENTRY_UNSPEC,
> > +     TCA_GATE_ONE_ENTRY,
> > +     __TCA_GATE_ONE_ENTRY_MAX,
> > +};
> > +#define TCA_GATE_ONE_ENTRY_MAX (__TCA_GATE_ONE_ENTRY_MAX
> - 1)
> > +
> > +enum {
> > +     TCA_GATE_UNSPEC,
> > +     TCA_GATE_TM,
> > +     TCA_GATE_PARMS,
> > +     TCA_GATE_PAD,
> > +     TCA_GATE_PRIORITY,
> > +     TCA_GATE_ENTRY_LIST,
> > +     TCA_GATE_BASE_TIME,
> > +     TCA_GATE_CYCLE_TIME,
> > +     TCA_GATE_CYCLE_TIME_EXT,
> > +     TCA_GATE_FLAGS,
> > +     TCA_GATE_CLOCKID,
> > +     __TCA_GATE_MAX,
> > +};
> > +#define TCA_GATE_MAX (__TCA_GATE_MAX - 1)
> > +
> > +#endif
> > diff --git a/net/sched/Kconfig b/net/sched/Kconfig index
> > bfbefb7bff9d..2f20073f4f84 100644
> > --- a/net/sched/Kconfig
> > +++ b/net/sched/Kconfig
> > @@ -981,6 +981,18 @@ config NET_ACT_CT
> >         To compile this code as a module, choose M here: the
> >         module will be called act_ct.
> >
> > +config NET_ACT_GATE
> > +     tristate "Frame gate entry list control tc action"
> > +     depends on NET_CLS_ACT
> > +     help
> > +       Say Y here to allow to control the ingress flow to be passed at
> > +       specific time slot and be dropped at other specific time slot by
> > +       the gate entry list.
> > +
> > +       If unsure, say N.
> > +       To compile this code as a module, choose M here: the
> > +       module will be called act_gate.
> > +
> >  config NET_IFE_SKBMARK
> >       tristate "Support to encoding decoding skb mark on IFE action"
> >       depends on NET_ACT_IFE
> > diff --git a/net/sched/Makefile b/net/sched/Makefile index
> > 31c367a6cd09..66bbf9a98f9e 100644
> > --- a/net/sched/Makefile
> > +++ b/net/sched/Makefile
> > @@ -30,6 +30,7 @@ obj-$(CONFIG_NET_IFE_SKBPRIO)       +=
> act_meta_skbprio.o
> >  obj-$(CONFIG_NET_IFE_SKBTCINDEX)     += act_meta_skbtcindex.o
> >  obj-$(CONFIG_NET_ACT_TUNNEL_KEY)+= act_tunnel_key.o
> >  obj-$(CONFIG_NET_ACT_CT)     += act_ct.o
> > +obj-$(CONFIG_NET_ACT_GATE)   += act_gate.o
> >  obj-$(CONFIG_NET_SCH_FIFO)   += sch_fifo.o
> >  obj-$(CONFIG_NET_SCH_CBQ)    += sch_cbq.o
> >  obj-$(CONFIG_NET_SCH_HTB)    += sch_htb.o
> > diff --git a/net/sched/act_gate.c b/net/sched/act_gate.c new file mode
> > 100644 index 000000000000..916f6fe56692
> > --- /dev/null
> > +++ b/net/sched/act_gate.c
> > @@ -0,0 +1,638 @@
> > +// SPDX-License-Identifier: GPL-2.0-or-later
> > +/* Copyright 2020 NXP */
> > +
> > +#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>
> > +#include <net/pkt_cls.h>
> > +#include <net/tc_act/tc_gate.h>
> > +
> > +static unsigned int gate_net_id;
> > +static struct tc_action_ops act_gate_ops;
> > +
> > +static ktime_t gate_get_time(struct tcf_gate *gact) {
> > +     ktime_t mono = ktime_get();
> > +
> > +     switch (gact->tk_offset) {
> > +     case TK_OFFS_MAX:
> > +             return mono;
> > +     default:
> > +             return ktime_mono_to_any(mono, gact->tk_offset);
> > +     }
> > +
> > +     return KTIME_MAX;
> > +}
> > +
> > +static int gate_get_start_time(struct tcf_gate *gact, ktime_t *start)
> > +{
> > +     struct tcf_gate_params *param = &gact->param;
> > +     ktime_t now, base, cycle;
> > +     u64 n;
> > +
> > +     base = ns_to_ktime(param->tcfg_basetime);
> > +     now = gate_get_time(gact);
> > +
> > +     if (ktime_after(base, now)) {
> > +             *start = base;
> > +             return 0;
> > +     }
> > +
> > +     cycle = param->tcfg_cycletime;
> > +
> > +     /* cycle time should not be zero */
> > +     if (!cycle)
> > +             return -EFAULT;
> > +
> > +     n = div64_u64(ktime_sub_ns(now, base), cycle);
> > +     *start = ktime_add_ns(base, (n + 1) * cycle);
> > +     return 0;
> > +}
> > +
> > +static void gate_start_timer(struct tcf_gate *gact, ktime_t start) {
> > +     ktime_t expires;
> > +
> > +     expires = hrtimer_get_expires(&gact->hitimer);
> > +     if (expires == 0)
> > +             expires = KTIME_MAX;
> > +
> > +     start = min_t(ktime_t, start, expires);
> > +
> > +     hrtimer_start(&gact->hitimer, start, HRTIMER_MODE_ABS); }
> > +
> > +static enum hrtimer_restart gate_timer_func(struct hrtimer *timer) {
> > +     struct tcf_gate *gact = container_of(timer, struct tcf_gate,
> > +                                          hitimer);
> > +     struct tcf_gate_params *p = &gact->param;
> > +     struct tcfg_gate_entry *next;
> > +     ktime_t close_time, now;
> > +
> > +     spin_lock(&gact->tcf_lock);
> > +
> > +     next = gact->next_entry;
> > +
> > +     /* cycle start, clear pending bit, clear total octets */
> > +     gact->current_gate_status = next->gate_state ?
> GATE_ACT_GATE_OPEN : 0;
> > +     gact->current_entry_octets = 0;
> > +     gact->current_max_octets = next->maxoctets;
> > +
> > +     gact->current_close_time = ktime_add_ns(gact->current_close_time,
> > +                                             next->interval);
> > +
> > +     close_time = gact->current_close_time;
> > +
> > +     if (list_is_last(&next->list, &p->entries))
> > +             next = list_first_entry(&p->entries,
> > +                                     struct tcfg_gate_entry, list);
> > +     else
> > +             next = list_next_entry(next, list);
> > +
> > +     now = gate_get_time(gact);
> > +
> > +     if (ktime_after(now, close_time)) {
> > +             ktime_t cycle, base;
> > +             u64 n;
> > +
> > +             cycle = p->tcfg_cycletime;
> > +             base = ns_to_ktime(p->tcfg_basetime);
> > +             n = div64_u64(ktime_sub_ns(now, base), cycle);
> > +             close_time = ktime_add_ns(base, (n + 1) * cycle);
> > +     }
> > +
> > +     gact->next_entry = next;
> > +
> > +     hrtimer_set_expires(&gact->hitimer, close_time);
> > +
> > +     spin_unlock(&gact->tcf_lock);
> > +
> > +     return HRTIMER_RESTART;
> > +}
> > +
> > +static int tcf_gate_act(struct sk_buff *skb, const struct tc_action *a,
> > +                     struct tcf_result *res) {
> > +     struct tcf_gate *gact = to_gate(a);
> > +
> > +     spin_lock_bh(&gact->tcf_lock);
> 
> I think you need to use regular spin_lock() function here because this
> function is called from softirq context.

Understand, I'll change to spin_lock().

> 
> > +
> > +     tcf_lastuse_update(&gact->tcf_tm);
> > +     bstats_update(&gact->tcf_bstats, skb);
> > +
> > +     if (unlikely(gact->current_gate_status & GATE_ACT_PENDING)) {
> > +             spin_unlock_bh(&gact->tcf_lock);
> > +             return gact->tcf_action;
> > +     }
> > +
> > +     if (!(gact->current_gate_status & GATE_ACT_GATE_OPEN))
> > +             goto drop;
> > +
> > +     if (gact->current_max_octets >= 0) {
> > +             gact->current_entry_octets += qdisc_pkt_len(skb);
> > +             if (gact->current_entry_octets > gact->current_max_octets) {
> > +                     gact->tcf_qstats.overlimits++;
> > +                     goto drop;
> > +             }
> > +     }
> > +
> > +     spin_unlock_bh(&gact->tcf_lock);
> > +
> > +     return gact->tcf_action;
> > +drop:
> > +     gact->tcf_qstats.drops++;
> > +     spin_unlock_bh(&gact->tcf_lock);
> > +
> > +     return TC_ACT_SHOT;
> > +}
> > +
> > +static const struct nla_policy entry_policy[TCA_GATE_ENTRY_MAX + 1]
> = {
> > +     [TCA_GATE_ENTRY_INDEX]          = { .type = NLA_U32 },
> > +     [TCA_GATE_ENTRY_GATE]           = { .type = NLA_FLAG },
> > +     [TCA_GATE_ENTRY_INTERVAL]       = { .type = NLA_U32 },
> > +     [TCA_GATE_ENTRY_IPV]            = { .type = NLA_S32 },
> > +     [TCA_GATE_ENTRY_MAX_OCTETS]     = { .type = NLA_S32 },
> > +};
> > +
> > +static const struct nla_policy gate_policy[TCA_GATE_MAX + 1] = {
> > +     [TCA_GATE_PARMS]                = { .len = sizeof(struct tc_gate),
> > +                                         .type = NLA_EXACT_LEN },
> > +     [TCA_GATE_PRIORITY]             = { .type = NLA_S32 },
> > +     [TCA_GATE_ENTRY_LIST]           = { .type = NLA_NESTED },
> > +     [TCA_GATE_BASE_TIME]            = { .type = NLA_U64 },
> > +     [TCA_GATE_CYCLE_TIME]           = { .type = NLA_U64 },
> > +     [TCA_GATE_CYCLE_TIME_EXT]       = { .type = NLA_U64 },
> > +     [TCA_GATE_FLAGS]                = { .type = NLA_U32 },
> > +     [TCA_GATE_CLOCKID]              = { .type = NLA_S32 },
> > +};
> > +
> > +static int fill_gate_entry(struct nlattr **tb, struct tcfg_gate_entry *entry,
> > +                        struct netlink_ext_ack *extack) {
> > +     u32 interval = 0;
> > +
> > +     entry->gate_state = nla_get_flag(tb[TCA_GATE_ENTRY_GATE]);
> > +
> > +     if (tb[TCA_GATE_ENTRY_INTERVAL])
> > +             interval = nla_get_u32(tb[TCA_GATE_ENTRY_INTERVAL]);
> > +
> > +     if (interval == 0) {
> > +             NL_SET_ERR_MSG(extack, "Invalid interval for schedule entry");
> > +             return -EINVAL;
> > +     }
> > +
> > +     entry->interval = interval;
> > +
> > +     if (tb[TCA_GATE_ENTRY_IPV])
> > +             entry->ipv = nla_get_s32(tb[TCA_GATE_ENTRY_IPV]);
> > +     else
> > +             entry->ipv = -1;
> > +
> > +     if (tb[TCA_GATE_ENTRY_MAX_OCTETS])
> > +             entry->maxoctets =
> nla_get_s32(tb[TCA_GATE_ENTRY_MAX_OCTETS]);
> > +     else
> > +             entry->maxoctets = -1;
> > +
> > +     return 0;
> > +}
> > +
> > +static int parse_gate_entry(struct nlattr *n, struct  tcfg_gate_entry
> *entry,
> > +                         int index, struct netlink_ext_ack *extack) {
> > +     struct nlattr *tb[TCA_GATE_ENTRY_MAX + 1] = { };
> > +     int err;
> > +
> > +     err = nla_parse_nested(tb, TCA_GATE_ENTRY_MAX, n, entry_policy,
> extack);
> > +     if (err < 0) {
> > +             NL_SET_ERR_MSG(extack, "Could not parse nested entry");
> > +             return -EINVAL;
> > +     }
> > +
> > +     entry->index = index;
> > +
> > +     return fill_gate_entry(tb, entry, extack); }
> > +
> > +static void release_entry_list(struct list_head *entries) {
> > +     struct tcfg_gate_entry *entry, *e;
> > +
> > +     list_for_each_entry_safe(entry, e, entries, list) {
> > +             list_del(&entry->list);
> > +             kfree(entry);
> > +     }
> > +}
> > +
> > +static int parse_gate_list(struct nlattr *list_attr,
> > +                        struct tcf_gate_params *sched,
> > +                        struct netlink_ext_ack *extack) {
> > +     struct tcfg_gate_entry *entry;
> > +     struct nlattr *n;
> > +     int err, rem;
> > +     int i = 0;
> > +
> > +     if (!list_attr)
> > +             return -EINVAL;
> > +
> > +     nla_for_each_nested(n, list_attr, rem) {
> > +             if (nla_type(n) != TCA_GATE_ONE_ENTRY) {
> > +                     NL_SET_ERR_MSG(extack, "Attribute isn't type 'entry'");
> > +                     continue;
> > +             }
> > +
> > +             entry = kzalloc(sizeof(*entry), GFP_KERNEL);
> > +             if (!entry) {
> > +                     NL_SET_ERR_MSG(extack, "Not enough memory for entry");
> > +                     err = -ENOMEM;
> > +                     goto release_list;
> > +             }
> > +
> > +             err = parse_gate_entry(n, entry, i, extack);
> > +             if (err < 0) {
> > +                     kfree(entry);
> > +                     goto release_list;
> > +             }
> > +
> > +             list_add_tail(&entry->list, &sched->entries);
> > +             i++;
> > +     }
> > +
> > +     sched->num_entries = i;
> > +
> > +     return i;
> > +
> > +release_list:
> > +     release_entry_list(&sched->entries);
> > +
> > +     return err;
> > +}
> > +
> > +static int tcf_gate_init(struct net *net, struct nlattr *nla,
> > +                      struct nlattr *est, struct tc_action **a,
> > +                      int ovr, int bind, bool rtnl_held,
> > +                      struct tcf_proto *tp, u32 flags,
> > +                      struct netlink_ext_ack *extack) {
> > +     struct tc_action_net *tn = net_generic(net, gate_net_id);
> > +     enum tk_offsets tk_offset = TK_OFFS_TAI;
> > +     struct nlattr *tb[TCA_GATE_MAX + 1];
> > +     struct tcf_chain *goto_ch = NULL;
> > +     struct tcf_gate_params *p;
> > +     s32 clockid = CLOCK_TAI;
> > +     struct tcf_gate *gact;
> > +     struct tc_gate *parm;
> > +     int ret = 0, err;
> > +     u64 basetime = 0;
> > +     u32 gflags = 0;
> > +     s32 prio = -1;
> > +     ktime_t start;
> > +     u32 index;
> > +
> > +     if (!nla)
> > +             return -EINVAL;
> > +
> > +     err = nla_parse_nested(tb, TCA_GATE_MAX, nla, gate_policy, extack);
> > +     if (err < 0)
> > +             return err;
> > +
> > +     if (!tb[TCA_GATE_PARMS])
> > +             return -EINVAL;
> > +
> > +     parm = nla_data(tb[TCA_GATE_PARMS]);
> > +     index = parm->index;
> > +
> > +     err = tcf_idr_check_alloc(tn, &index, a, bind);
> > +     if (err < 0)
> > +             return err;
> > +
> > +     if (err && bind)
> > +             return 0;
> > +
> > +     if (!err) {
> > +             ret = tcf_idr_create(tn, index, est, a,
> > +                                  &act_gate_ops, bind, false, 0);
> > +             if (ret) {
> > +                     tcf_idr_cleanup(tn, index);
> > +                     return ret;
> > +             }
> > +
> > +             ret = ACT_P_CREATED;
> > +     } else if (!ovr) {
> > +             tcf_idr_release(*a, bind);
> > +             return -EEXIST;
> > +     }
> > +
> > +     if (tb[TCA_GATE_PRIORITY])
> > +             prio = nla_get_s32(tb[TCA_GATE_PRIORITY]);
> > +
> > +     if (tb[TCA_GATE_BASE_TIME])
> > +             basetime = nla_get_u64(tb[TCA_GATE_BASE_TIME]);
> > +
> > +     if (tb[TCA_GATE_FLAGS])
> > +             gflags = nla_get_u32(tb[TCA_GATE_FLAGS]);
> > +
> > +     if (tb[TCA_GATE_CLOCKID]) {
> > +             clockid = nla_get_s32(tb[TCA_GATE_CLOCKID]);
> > +             switch (clockid) {
> > +             case CLOCK_REALTIME:
> > +                     tk_offset = TK_OFFS_REAL;
> > +                     break;
> > +             case CLOCK_MONOTONIC:
> > +                     tk_offset = TK_OFFS_MAX;
> > +                     break;
> > +             case CLOCK_BOOTTIME:
> > +                     tk_offset = TK_OFFS_BOOT;
> > +                     break;
> > +             case CLOCK_TAI:
> > +                     tk_offset = TK_OFFS_TAI;
> > +                     break;
> > +             default:
> > +                     NL_SET_ERR_MSG(extack, "Invalid 'clockid'");
> > +                     goto release_idr;
> > +             }
> > +     }
> > +
> > +     err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack);
> > +     if (err < 0)
> > +             goto release_idr;
> > +
> > +     gact = to_gate(*a);
> > +
> > +     spin_lock_bh(&gact->tcf_lock);
> > +     p = &gact->param;
> > +
> > +     if (tb[TCA_GATE_CYCLE_TIME]) {
> > +             p->tcfg_cycletime = nla_get_u64(tb[TCA_GATE_CYCLE_TIME]);
> > +             if (!p->tcfg_cycletime_ext)
> > +                     goto chain_put;
> > +     }
> > +
> > +     INIT_LIST_HEAD(&p->entries);
> > +     if (tb[TCA_GATE_ENTRY_LIST]) {
> > +             err = parse_gate_list(tb[TCA_GATE_ENTRY_LIST], p, extack);
> > +             if (err < 0)
> > +                     goto chain_put;
> > +     }
> > +
> > +     if (!p->tcfg_cycletime) {
> > +             struct tcfg_gate_entry *entry;
> > +             ktime_t cycle = 0;
> > +
> > +             list_for_each_entry(entry, &p->entries, list)
> > +                     cycle = ktime_add_ns(cycle, entry->interval);
> > +             p->tcfg_cycletime = cycle;
> > +     }
> > +
> > +     if (tb[TCA_GATE_CYCLE_TIME_EXT])
> > +             p->tcfg_cycletime_ext =
> > +                     nla_get_u64(tb[TCA_GATE_CYCLE_TIME_EXT]);
> > +
> > +     p->tcfg_priority = prio;
> > +     p->tcfg_basetime = basetime;
> > +     p->tcfg_clockid = clockid;
> > +     p->tcfg_flags = gflags;
> > +
> > +     gact->tk_offset = tk_offset;
> > +     hrtimer_init(&gact->hitimer, clockid, HRTIMER_MODE_ABS);
> > +     gact->hitimer.function = gate_timer_func;
> > +
> > +     err = gate_get_start_time(gact, &start);
> > +     if (err < 0) {
> > +             NL_SET_ERR_MSG(extack,
> > +                            "Internal error: failed get start time");
> > +             release_entry_list(&p->entries);
> > +             goto chain_put;
> > +     }
> > +
> > +     gact->current_close_time = start;
> > +     gact->current_gate_status = GATE_ACT_GATE_OPEN |
> > + GATE_ACT_PENDING;
> > +
> > +     gact->next_entry = list_first_entry(&p->entries,
> > +                                         struct tcfg_gate_entry,
> > + list);
> > +
> > +     goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch);
> > +
> > +     gate_start_timer(gact, start);
> > +
> > +     spin_unlock_bh(&gact->tcf_lock);
> > +
> > +     if (goto_ch)
> > +             tcf_chain_put_by_act(goto_ch);
> > +
> > +     if (ret == ACT_P_CREATED)
> > +             tcf_idr_insert(tn, *a);
> > +     return ret;
> > +
> > +chain_put:
> > +     spin_unlock_bh(&gact->tcf_lock);
> > +
> > +     if (goto_ch)
> > +             tcf_chain_put_by_act(goto_ch);
> > +release_idr:
> > +     tcf_idr_release(*a, bind);
> > +     return err;
> > +}
> > +
> > +static void tcf_gate_cleanup(struct tc_action *a) {
> > +     struct tcf_gate *gact = to_gate(a);
> > +     struct tcf_gate_params *p;
> > +
> > +     spin_lock_bh(&gact->tcf_lock);
> 
> No need to lock in tc_action_ops->cleanup() callbacks.

I'll remove the lock in cleanup callback. Thanks!

> 
> > +
> > +     hrtimer_cancel(&gact->hitimer);
> > +
> > +     p = &gact->param;
> > +     release_entry_list(&p->entries);
> > +
> > +     spin_unlock_bh(&gact->tcf_lock); }
> > +
> > +static int dumping_entry(struct sk_buff *skb,
> > +                      struct tcfg_gate_entry *entry) {
> > +     struct nlattr *item;
> > +
> > +     item = nla_nest_start_noflag(skb, TCA_GATE_ONE_ENTRY);
> > +     if (!item)
> > +             return -ENOSPC;
> > +
> > +     if (nla_put_u32(skb, TCA_GATE_ENTRY_INDEX, entry->index))
> > +             goto nla_put_failure;
> > +
> > +     if (entry->gate_state && nla_put_flag(skb, TCA_GATE_ENTRY_GATE))
> > +             goto nla_put_failure;
> > +
> > +     if (nla_put_u32(skb, TCA_GATE_ENTRY_INTERVAL, entry->interval))
> > +             goto nla_put_failure;
> > +
> > +     if (nla_put_s32(skb, TCA_GATE_ENTRY_MAX_OCTETS, entry-
> >maxoctets))
> > +             goto nla_put_failure;
> > +
> > +     if (nla_put_s32(skb, TCA_GATE_ENTRY_IPV, entry->ipv))
> > +             goto nla_put_failure;
> > +
> > +     return nla_nest_end(skb, item);
> > +
> > +nla_put_failure:
> > +     nla_nest_cancel(skb, item);
> > +     return -1;
> > +}
> > +
> > +static int tcf_gate_dump(struct sk_buff *skb, struct tc_action *a,
> > +                      int bind, int ref) {
> > +     unsigned char *b = skb_tail_pointer(skb);
> > +     struct tcf_gate *gact = to_gate(a);
> > +     struct tc_gate opt = {
> > +             .index    = gact->tcf_index,
> > +             .refcnt   = refcount_read(&gact->tcf_refcnt) - ref,
> > +             .bindcnt  = atomic_read(&gact->tcf_bindcnt) - bind,
> > +     };
> > +     struct tcfg_gate_entry *entry;
> > +     struct tcf_gate_params *p;
> > +     struct nlattr *entry_list;
> > +     struct tcf_t t;
> > +
> > +     spin_lock_bh(&gact->tcf_lock);
> > +     opt.action = gact->tcf_action;
> > +
> > +     p = &gact->param;
> > +
> > +     if (nla_put(skb, TCA_GATE_PARMS, sizeof(opt), &opt))
> > +             goto nla_put_failure;
> > +
> > +     if (nla_put_u64_64bit(skb, TCA_GATE_BASE_TIME,
> > +                           p->tcfg_basetime, TCA_GATE_PAD))
> > +             goto nla_put_failure;
> > +
> > +     if (nla_put_u64_64bit(skb, TCA_GATE_CYCLE_TIME,
> > +                           p->tcfg_cycletime, TCA_GATE_PAD))
> > +             goto nla_put_failure;
> > +
> > +     if (nla_put_u64_64bit(skb, TCA_GATE_CYCLE_TIME_EXT,
> > +                           p->tcfg_cycletime_ext, TCA_GATE_PAD))
> > +             goto nla_put_failure;
> > +
> > +     if (nla_put_s32(skb, TCA_GATE_CLOCKID, p->tcfg_clockid))
> > +             goto nla_put_failure;
> > +
> > +     if (nla_put_u32(skb, TCA_GATE_FLAGS, p->tcfg_flags))
> > +             goto nla_put_failure;
> > +
> > +     if (nla_put_s32(skb, TCA_GATE_PRIORITY, p->tcfg_priority))
> > +             goto nla_put_failure;
> > +
> > +     entry_list = nla_nest_start_noflag(skb, TCA_GATE_ENTRY_LIST);
> > +     if (!entry_list)
> > +             goto nla_put_failure;
> > +
> > +     list_for_each_entry(entry, &p->entries, list) {
> > +             if (dumping_entry(skb, entry) < 0)
> > +                     goto nla_put_failure;
> > +     }
> > +
> > +     nla_nest_end(skb, entry_list);
> > +
> > +     tcf_tm_dump(&t, &gact->tcf_tm);
> > +     if (nla_put_64bit(skb, TCA_GATE_TM, sizeof(t), &t, TCA_GATE_PAD))
> > +             goto nla_put_failure;
> > +     spin_unlock_bh(&gact->tcf_lock);
> > +
> > +     return skb->len;
> > +
> > +nla_put_failure:
> > +     spin_unlock_bh(&gact->tcf_lock);
> > +     nlmsg_trim(skb, b);
> > +     return -1;
> > +}
> > +
> > +static int tcf_gate_walker(struct net *net, struct sk_buff *skb,
> > +                        struct netlink_callback *cb, int type,
> > +                        const struct tc_action_ops *ops,
> > +                        struct netlink_ext_ack *extack) {
> > +     struct tc_action_net *tn = net_generic(net, gate_net_id);
> > +
> > +     return tcf_generic_walker(tn, skb, cb, type, ops, extack); }
> > +
> > +static void tcf_gate_stats_update(struct tc_action *a, u64 bytes, u32
> packets,
> > +                               u64 lastuse, bool hw) {
> > +     struct tcf_gate *gact = to_gate(a);
> > +     struct tcf_t *tm = &gact->tcf_tm;
> > +
> > +     tcf_action_update_stats(a, bytes, packets, false, hw);
> > +     tm->lastuse = max_t(u64, tm->lastuse, lastuse); }
> > +
> > +static int tcf_gate_search(struct net *net, struct tc_action **a, u32
> > +index) {
> > +     struct tc_action_net *tn = net_generic(net, gate_net_id);
> > +
> > +     return tcf_idr_search(tn, a, index); }
> > +
> > +static size_t tcf_gate_get_fill_size(const struct tc_action *act) {
> > +     return nla_total_size(sizeof(struct tc_gate)); }
> > +
> > +static struct tc_action_ops act_gate_ops = {
> > +     .kind           =       "gate",
> > +     .id             =       TCA_ID_GATE,
> > +     .owner          =       THIS_MODULE,
> > +     .act            =       tcf_gate_act,
> > +     .dump           =       tcf_gate_dump,
> > +     .init           =       tcf_gate_init,
> > +     .cleanup        =       tcf_gate_cleanup,
> > +     .walk           =       tcf_gate_walker,
> > +     .stats_update   =       tcf_gate_stats_update,
> > +     .get_fill_size  =       tcf_gate_get_fill_size,
> > +     .lookup         =       tcf_gate_search,
> > +     .size           =       sizeof(struct tcf_gate),
> > +};
> > +
> > +static __net_init int gate_init_net(struct net *net) {
> > +     struct tc_action_net *tn = net_generic(net, gate_net_id);
> > +
> > +     return tc_action_net_init(net, tn, &act_gate_ops); }
> > +
> > +static void __net_exit gate_exit_net(struct list_head *net_list) {
> > +     tc_action_net_exit(net_list, gate_net_id); }
> > +
> > +static struct pernet_operations gate_net_ops = {
> > +     .init = gate_init_net,
> > +     .exit_batch = gate_exit_net,
> > +     .id   = &gate_net_id,
> > +     .size = sizeof(struct tc_action_net), };
> > +
> > +static int __init gate_init_module(void) {
> > +     return tcf_register_action(&act_gate_ops, &gate_net_ops); }
> > +
> > +static void __exit gate_cleanup_module(void) {
> > +     tcf_unregister_action(&act_gate_ops, &gate_net_ops); }
> > +
> > +module_init(gate_init_module);
> > +module_exit(gate_cleanup_module);
> > +MODULE_LICENSE("GPL v2");

Thanks a lot.

Br,
Po Liu