RE: [EXT] Re: [RFC,net-next 2/9] net: qos: introduce a gate control flow action

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

Hi Jakub,

> -----Original Message-----
> From: Jakub Kicinski <kuba@kernel.org>
> Sent: 2020年3月7日 3:11
> 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>; Xiaoliang Yang
> <xiaoliang.yang_1@nxp.com>; Roy Zang <roy.zang@nxp.com>; Mingkai Hu
> <mingkai.hu@nxp.com>; Jerry Huang <jerry.huang@nxp.com>; Leo Li
> <leoyang.li@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; jhs@mojatatu.com;
> xiyou.wangcong@gmail.com; john.hurley@netronome.com;
> simon.horman@netronome.com;
> pieter.jansenvanvuuren@netronome.com; pablo@netfilter.org;
> moshe@mellanox.com; ivan.khoronzhuk@linaro.org; m-karicheri2@ti.com;
> andre.guedes@linux.intel.com; jakub.kicinski@netronome.com
> Subject: [EXT] Re: [RFC,net-next 2/9] net: qos: introduce a gate control flow
> action
> 
> Caution: EXT Email
> 
> On Fri,  6 Mar 2020 20:56:00 +0800 Po Liu wrote:
> > Introduce a ingress frame gate control flow action. tc create a gate
> > action would provide a gate list to control when open/close state.
> > when the gate open state, the flow could pass but not when gate state
> > is close. The driver would repeat the gate list cyclically. User also
> > could assign a time point to start the gate list by the basetime
> > parameter. if the basetime has passed current time, start time would
> > calculate by the cycletime of the gate list.
> > The action gate behavior try to keep according to the IEEE 802.1Qci spec.
> > For the software simulation, require the user input the clock type.
> >
> > Below is the setting example in user space:
> >
> > > 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 \
> >          sched-entry OPEN 200000000 -1 -1 \
> >          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 the period nanosecond. Then next -1 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.
> >
> > NOTE: This software simulator version not separate the
> admin/operation
> > state machine. Update setting would overwrite stop the previos setting
> > and waiting new cycle start.
> >
> > Signed-off-by: Po Liu <Po.Liu@nxp.com>
> 
> > diff --git a/net/sched/act_gate.c b/net/sched/act_gate.c new file mode
> > 100644 index 000000000000..c2c243ca028c
> > --- /dev/null
> > +++ b/net/sched/act_gate.c
> > @@ -0,0 +1,645 @@
> > +// SPDX-License-Identifier: (GPL-2.0+)
> 
> Why the parenthesis?

Will changed to GPL-2.0-or-later.

> 
> > +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) },
> > +     [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;
> > +
> > +     if (tb[TCA_GATE_ENTRY_GATE])
> > +             entry->gate_state = 1;
> > +     else
> > +             entry->gate_state = 0;
> 
> nla_get_flag()

Ok,  will parse by the nla_get_flag()

> 
> > +
> > +     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;
> > +     }
> 
> > +static int parse_gate_list(struct nlattr *list,
> > +                        struct tcf_gate_params *sched,
> > +                        struct netlink_ext_ack *extack) {
> > +     struct nlattr *n;
> > +     int err, rem;
> > +     int i = 0;
> > +
> > +     if (!list)
> > +             return -EINVAL;
> > +
> > +     nla_for_each_nested(n, list, rem) {
> > +             struct tcfg_gate_entry *entry;
> > +
> > +             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");
> > +                     return -ENOMEM;
> > +             }
> > +
> > +             err = parse_gate_entry(n, entry, i, extack);
> > +             if (err < 0) {
> > +                     kfree(entry);
> 
> doesn't this leak previously added entries?

Ok, will fix it.

> 
> > +                     return err;
> > +             }
> > +
> > +             list_add_tail(&entry->list, &sched->entries);
> > +             i++;
> > +     }
> > +
> > +     sched->num_entries = i;
> > +
> > +     return i;
> > +}
> 
> 
> > +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_deprecated(tb, TCA_GATE_ENTRY_MAX, n,
> 
> Please don't use the deprecated calls in new code.

Understand, will change to nla_parse_nested()

> 
> > +                                       entry_policy, NULL);
> > +     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); }

Thanks!

Po Liu