Message-ID: <DM5PR1301MB2172C90CF04E14EA7FAD5528E78A9@DM5PR1301MB2172.namprd13.prod.outlook.com>
Date:   Mon, 1 Nov 2021 02:30:05 +0000
From:   Baowen Zheng <baowen.zheng@...igine.com>
To:     Oz Shlomo <ozsh@...dia.com>,
        Simon Horman <simon.horman@...igine.com>,
        "netdev@...r.kernel.org" <netdev@...r.kernel.org>
CC:     Vlad Buslov <vladbu@...dia.com>,
        Jamal Hadi Salim <jhs@...atatu.com>,
        Roi Dayan <roid@...dia.com>, Ido Schimmel <idosch@...dia.com>,
        Cong Wang <xiyou.wangcong@...il.com>,
        Jiri Pirko <jiri@...nulli.us>,
        Baowen Zheng <notifications@...hub.com>,
        Louis Peens <louis.peens@...igine.com>,
        oss-drivers <oss-drivers@...igine.com>
Subject: RE: [RFC/PATCH net-next v3 3/8] flow_offload: allow user to offload
 tc action to net device

On 10/31/2021 5:50 PM, Oz Shlomo wrote:
>On 10/28/2021 2:06 PM, Simon Horman wrote:
>> From: Baowen Zheng <baowen.zheng@...igine.com>
>>
>> Use flow_indr_dev_register/flow_indr_dev_setup_offload to offload tc
>> action.
>
>How will device drivers reference the offloaded actions when offloading a
>flow?
>Perhaps the flow_action_entry structure should also include the action index.
>
We have set action index in flow_offload_action to offload the action, also there are
already some actions in flow_action_entry include index which we want to offload.
If the driver wants to support action that needs index, I think it can add the index later,
it may not include in this patch, WDYT?
>>
>> We need to call tc_cleanup_flow_action to clean up tc action entry
>> since in tc_setup_action, some actions may hold dev refcnt, especially
>> the mirror action.
>>
>> Signed-off-by: Baowen Zheng <baowen.zheng@...igine.com>
>> Signed-off-by: Louis Peens <louis.peens@...igine.com>
>> Signed-off-by: Simon Horman <simon.horman@...igine.com>
>> ---
>>   include/linux/netdevice.h  |   1 +
>>   include/net/act_api.h      |   2 +-
>>   include/net/flow_offload.h |  17 ++++
>>   include/net/pkt_cls.h      |  15 ++++
>>   net/core/flow_offload.c    |  43 ++++++++--
>>   net/sched/act_api.c        | 166 +++++++++++++++++++++++++++++++++++++
>>   net/sched/cls_api.c        |  29 ++++++-
>>   7 files changed, 260 insertions(+), 13 deletions(-)
>>
>> diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
>> index 3ec42495a43a..9815c3a058e9 100644
>> --- a/include/linux/netdevice.h
>> +++ b/include/linux/netdevice.h
>> @@ -916,6 +916,7 @@ enum tc_setup_type {
>>   	TC_SETUP_QDISC_TBF,
>>   	TC_SETUP_QDISC_FIFO,
>>   	TC_SETUP_QDISC_HTB,
>> +	TC_SETUP_ACT,
>>   };
>>
>>   /* These structures hold the attributes of bpf state that are being
>> passed diff --git a/include/net/act_api.h b/include/net/act_api.h
>> index b5b624c7e488..9eb19188603c 100644
>> --- a/include/net/act_api.h
>> +++ b/include/net/act_api.h
>> @@ -239,7 +239,7 @@ static inline void
>tcf_action_inc_overlimit_qstats(struct tc_action *a)
>>   void tcf_action_update_stats(struct tc_action *a, u64 bytes, u64 packets,
>>   			     u64 drops, bool hw);
>>   int tcf_action_copy_stats(struct sk_buff *, struct tc_action *,
>> int);
>> -
>> +int tcf_action_offload_del(struct tc_action *action);
>>   int tcf_action_check_ctrlact(int action, struct tcf_proto *tp,
>>   			     struct tcf_chain **handle,
>>   			     struct netlink_ext_ack *newchain); diff --git
>> a/include/net/flow_offload.h b/include/net/flow_offload.h index
>> 3961461d9c8b..aa28592fccc0 100644
>> --- a/include/net/flow_offload.h
>> +++ b/include/net/flow_offload.h
>> @@ -552,6 +552,23 @@ struct flow_cls_offload {
>>   	u32 classid;
>>   };
>>
>> +enum flow_act_command {
>> +	FLOW_ACT_REPLACE,
>> +	FLOW_ACT_DESTROY,
>> +	FLOW_ACT_STATS,
>> +};
>> +
>> +struct flow_offload_action {
>> +	struct netlink_ext_ack *extack; /* NULL in FLOW_ACT_STATS
>process*/
>> +	enum flow_act_command command;
>> +	enum flow_action_id id;
>> +	u32 index;
>> +	struct flow_stats stats;
>> +	struct flow_action action;
>> +};
>> +
>> +struct flow_offload_action *flow_action_alloc(unsigned int
>> +num_actions);
>> +
>>   static inline struct flow_rule *
>>   flow_cls_offload_flow_rule(struct flow_cls_offload *flow_cmd)
>>   {
>> diff --git a/include/net/pkt_cls.h b/include/net/pkt_cls.h index
>> 193f88ebf629..922775407257 100644
>> --- a/include/net/pkt_cls.h
>> +++ b/include/net/pkt_cls.h
>> @@ -258,6 +258,9 @@ static inline void tcf_exts_put_net(struct tcf_exts
>*exts)
>>   	for (; 0; (void)(i), (void)(a), (void)(exts))
>>   #endif
>>
>> +#define tcf_act_for_each_action(i, a, actions) \
>> +	for (i = 0; i < TCA_ACT_MAX_PRIO && ((a) = actions[i]); i++)
>> +
>>   static inline void
>>   tcf_exts_stats_update(const struct tcf_exts *exts,
>>   		      u64 bytes, u64 packets, u64 drops, u64 lastuse, @@ -532,8
>> +535,19 @@ tcf_match_indev(struct sk_buff *skb, int ifindex)
>>   	return ifindex == skb->skb_iif;
>>   }
>>
>> +#ifdef CONFIG_NET_CLS_ACT
>>   int tc_setup_flow_action(struct flow_action *flow_action,
>>   			 const struct tcf_exts *exts);
>> +#else
>> +static inline int tc_setup_flow_action(struct flow_action *flow_action,
>> +				       const struct tcf_exts *exts) {
>> +	return 0;
>> +}
>> +#endif
>> +
>> +int tc_setup_action(struct flow_action *flow_action,
>> +		    struct tc_action *actions[]);
>>   void tc_cleanup_flow_action(struct flow_action *flow_action);
>>
>>   int tc_setup_cb_call(struct tcf_block *block, enum tc_setup_type
>> type, @@ -554,6 +568,7 @@ int tc_setup_cb_reoffload(struct tcf_block
>*block, struct tcf_proto *tp,
>>   			  enum tc_setup_type type, void *type_data,
>>   			  void *cb_priv, u32 *flags, unsigned int
>*in_hw_count);
>>   unsigned int tcf_exts_num_actions(struct tcf_exts *exts);
>> +unsigned int tcf_act_num_actions_single(struct tc_action *act);
>>
>>   #ifdef CONFIG_NET_CLS_ACT
>>   int tcf_qevent_init(struct tcf_qevent *qe, struct Qdisc *sch, diff
>> --git a/net/core/flow_offload.c b/net/core/flow_offload.c index
>> 6beaea13564a..6676431733ef 100644
>> --- a/net/core/flow_offload.c
>> +++ b/net/core/flow_offload.c
>> @@ -27,6 +27,27 @@ struct flow_rule *flow_rule_alloc(unsigned int
>num_actions)
>>   }
>>   EXPORT_SYMBOL(flow_rule_alloc);
>>
>> +struct flow_offload_action *flow_action_alloc(unsigned int
>> +num_actions) {
>> +	struct flow_offload_action *fl_action;
>> +	int i;
>> +
>> +	fl_action = kzalloc(struct_size(fl_action, action.entries, num_actions),
>> +			    GFP_KERNEL);
>> +	if (!fl_action)
>> +		return NULL;
>> +
>> +	fl_action->action.num_entries = num_actions;
>> +	/* Pre-fill each action hw_stats with DONT_CARE.
>> +	 * Caller can override this if it wants stats for a given action.
>> +	 */
>> +	for (i = 0; i < num_actions; i++)
>> +		fl_action->action.entries[i].hw_stats =
>> +FLOW_ACTION_HW_STATS_DONT_CARE;
>> +
>> +	return fl_action;
>> +}
>> +EXPORT_SYMBOL(flow_action_alloc);
>> +
>>   #define FLOW_DISSECTOR_MATCH(__rule, __type, __out)
>		\
>>   	const struct flow_match *__m = &(__rule)->match;
>	\
>>   	struct flow_dissector *__d = (__m)->dissector;
>	\
>> @@ -549,19 +570,25 @@ int flow_indr_dev_setup_offload(struct
>net_device *dev,	struct Qdisc *sch,
>>   				void (*cleanup)(struct flow_block_cb
>*block_cb))
>>   {
>>   	struct flow_indr_dev *this;
>> +	u32 count = 0;
>> +	int err;
>>
>>   	mutex_lock(&flow_indr_block_lock);
>> +	if (bo) {
>> +		if (bo->command == FLOW_BLOCK_BIND)
>> +			indir_dev_add(data, dev, sch, type, cleanup, bo);
>> +		else if (bo->command == FLOW_BLOCK_UNBIND)
>> +			indir_dev_remove(data);
>> +	}
>>
>> -	if (bo->command == FLOW_BLOCK_BIND)
>> -		indir_dev_add(data, dev, sch, type, cleanup, bo);
>> -	else if (bo->command == FLOW_BLOCK_UNBIND)
>> -		indir_dev_remove(data);
>> -
>> -	list_for_each_entry(this, &flow_block_indr_dev_list, list)
>> -		this->cb(dev, sch, this->cb_priv, type, bo, data, cleanup);
>> +	list_for_each_entry(this, &flow_block_indr_dev_list, list) {
>> +		err = this->cb(dev, sch, this->cb_priv, type, bo, data, cleanup);
>> +		if (!err)
>> +			count++;
>> +	}
>>
>>   	mutex_unlock(&flow_indr_block_lock);
>>
>> -	return list_empty(&bo->cb_list) ? -EOPNOTSUPP : 0;
>> +	return (bo && list_empty(&bo->cb_list)) ? -EOPNOTSUPP : count;
>>   }
>>   EXPORT_SYMBOL(flow_indr_dev_setup_offload);
>> diff --git a/net/sched/act_api.c b/net/sched/act_api.c index
>> 3258da3d5bed..33f2ff885b4b 100644
>> --- a/net/sched/act_api.c
>> +++ b/net/sched/act_api.c
>> @@ -21,6 +21,19 @@
>>   #include <net/pkt_cls.h>
>>   #include <net/act_api.h>
>>   #include <net/netlink.h>
>> +#include <net/tc_act/tc_pedit.h>
>> +#include <net/tc_act/tc_mirred.h>
>> +#include <net/tc_act/tc_vlan.h>
>> +#include <net/tc_act/tc_tunnel_key.h> #include <net/tc_act/tc_csum.h>
>> +#include <net/tc_act/tc_gact.h> #include <net/tc_act/tc_police.h>
>> +#include <net/tc_act/tc_sample.h> #include <net/tc_act/tc_skbedit.h>
>> +#include <net/tc_act/tc_ct.h> #include <net/tc_act/tc_mpls.h>
>> +#include <net/tc_act/tc_gate.h> #include <net/flow_offload.h>
>>
>>   #ifdef CONFIG_INET
>>   DEFINE_STATIC_KEY_FALSE(tcf_frag_xmit_count);
>> @@ -148,6 +161,7 @@ static int __tcf_action_put(struct tc_action *p, bool
>bind)
>>   		idr_remove(&idrinfo->action_idr, p->tcfa_index);
>>   		mutex_unlock(&idrinfo->lock);
>>
>> +		tcf_action_offload_del(p);
>>   		tcf_action_cleanup(p);
>>   		return 1;
>>   	}
>> @@ -341,6 +355,7 @@ static int tcf_idr_release_unsafe(struct tc_action *p)
>>   		return -EPERM;
>>
>>   	if (refcount_dec_and_test(&p->tcfa_refcnt)) {
>> +		tcf_action_offload_del(p);
>>   		idr_remove(&p->idrinfo->action_idr, p->tcfa_index);
>>   		tcf_action_cleanup(p);
>>   		return ACT_P_DELETED;
>> @@ -452,6 +467,7 @@ static int tcf_idr_delete_index(struct tcf_idrinfo
>*idrinfo, u32 index)
>>   						p->tcfa_index));
>>   			mutex_unlock(&idrinfo->lock);
>>
>> +			tcf_action_offload_del(p);
>>   			tcf_action_cleanup(p);
>>   			module_put(owner);
>>   			return 0;
>> @@ -1061,6 +1077,154 @@ struct tc_action *tcf_action_init_1(struct net
>*net, struct tcf_proto *tp,
>>   	return ERR_PTR(err);
>>   }
>>
>> +static int flow_action_init(struct flow_offload_action *fl_action,
>> +			    struct tc_action *act,
>> +			    enum flow_act_command cmd,
>> +			    struct netlink_ext_ack *extack) {
>> +	if (!fl_action)
>> +		return -EINVAL;
>> +
>> +	fl_action->extack = extack;
>> +	fl_action->command = cmd;
>> +	fl_action->index = act->tcfa_index;
>> +
>> +	if (is_tcf_gact_ok(act)) {
>> +		fl_action->id = FLOW_ACTION_ACCEPT;
>> +	} else if (is_tcf_gact_shot(act)) {
>> +		fl_action->id = FLOW_ACTION_DROP;
>> +	} else if (is_tcf_gact_trap(act)) {
>> +		fl_action->id = FLOW_ACTION_TRAP;
>> +	} else if (is_tcf_gact_goto_chain(act)) {
>> +		fl_action->id = FLOW_ACTION_GOTO;
>> +	} else if (is_tcf_mirred_egress_redirect(act)) {
>> +		fl_action->id = FLOW_ACTION_REDIRECT;
>> +	} else if (is_tcf_mirred_egress_mirror(act)) {
>> +		fl_action->id = FLOW_ACTION_MIRRED;
>> +	} else if (is_tcf_mirred_ingress_redirect(act)) {
>> +		fl_action->id = FLOW_ACTION_REDIRECT_INGRESS;
>> +	} else if (is_tcf_mirred_ingress_mirror(act)) {
>> +		fl_action->id = FLOW_ACTION_MIRRED_INGRESS;
>> +	} else if (is_tcf_vlan(act)) {
>> +		switch (tcf_vlan_action(act)) {
>> +		case TCA_VLAN_ACT_PUSH:
>> +			fl_action->id = FLOW_ACTION_VLAN_PUSH;
>> +			break;
>> +		case TCA_VLAN_ACT_POP:
>> +			fl_action->id = FLOW_ACTION_VLAN_POP;
>> +			break;
>> +		case TCA_VLAN_ACT_MODIFY:
>> +			fl_action->id = FLOW_ACTION_VLAN_MANGLE;
>> +			break;
>> +		default:
>> +			return -EOPNOTSUPP;
>> +		}
>> +	} else if (is_tcf_tunnel_set(act)) {
>> +		fl_action->id = FLOW_ACTION_TUNNEL_ENCAP;
>> +	} else if (is_tcf_tunnel_release(act)) {
>> +		fl_action->id = FLOW_ACTION_TUNNEL_DECAP;
>> +	} else if (is_tcf_csum(act)) {
>> +		fl_action->id = FLOW_ACTION_CSUM;
>> +	} else if (is_tcf_skbedit_mark(act)) {
>> +		fl_action->id = FLOW_ACTION_MARK;
>> +	} else if (is_tcf_sample(act)) {
>> +		fl_action->id = FLOW_ACTION_SAMPLE;
>> +	} else if (is_tcf_police(act)) {
>> +		fl_action->id = FLOW_ACTION_POLICE;
>> +	} else if (is_tcf_ct(act)) {
>> +		fl_action->id = FLOW_ACTION_CT;
>> +	} else if (is_tcf_mpls(act)) {
>> +		switch (tcf_mpls_action(act)) {
>> +		case TCA_MPLS_ACT_PUSH:
>> +			fl_action->id = FLOW_ACTION_MPLS_PUSH;
>> +			break;
>> +		case TCA_MPLS_ACT_POP:
>> +			fl_action->id = FLOW_ACTION_MPLS_POP;
>> +			break;
>> +		case TCA_MPLS_ACT_MODIFY:
>> +			fl_action->id = FLOW_ACTION_MPLS_MANGLE;
>> +			break;
>> +		default:
>> +			return -EOPNOTSUPP;
>> +		}
>> +	} else if (is_tcf_skbedit_ptype(act)) {
>> +		fl_action->id = FLOW_ACTION_PTYPE;
>> +	} else if (is_tcf_skbedit_priority(act)) {
>> +		fl_action->id = FLOW_ACTION_PRIORITY;
>> +	} else if (is_tcf_gate(act)) {
>> +		fl_action->id = FLOW_ACTION_GATE;
>> +	} else {
>> +		return -EOPNOTSUPP;
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +static int tcf_action_offload_cmd(struct flow_offload_action *fl_act,
>> +				  struct netlink_ext_ack *extack) {
>> +	int err;
>> +
>> +	if (IS_ERR(fl_act))
>> +		return PTR_ERR(fl_act);
>> +
>> +	err = flow_indr_dev_setup_offload(NULL, NULL, TC_SETUP_ACT,
>> +					  fl_act, NULL, NULL);
>> +	if (err < 0)
>> +		return err;
>> +
>> +	return 0;
>> +}
>> +
>> +/* offload the tc command after inserted */ static int
>> +tcf_action_offload_add(struct tc_action *action,
>> +				  struct netlink_ext_ack *extack) {
>> +	struct tc_action *actions[TCA_ACT_MAX_PRIO] = {
>> +		[0] = action,
>> +	};
>> +	struct flow_offload_action *fl_action;
>> +	int err = 0;
>> +
>> +	fl_action = flow_action_alloc(tcf_act_num_actions_single(action));
>> +	if (!fl_action)
>> +		return -EINVAL;
>> +
>> +	err = flow_action_init(fl_action, action, FLOW_ACT_REPLACE, extack);
>> +	if (err)
>> +		goto fl_err;
>> +
>> +	err = tc_setup_action(&fl_action->action, actions);
>> +	if (err) {
>> +		NL_SET_ERR_MSG_MOD(extack,
>> +				   "Failed to setup tc actions for offload\n");
>> +		goto fl_err;
>> +	}
>> +
>> +	err = tcf_action_offload_cmd(fl_action, extack);
>> +	tc_cleanup_flow_action(&fl_action->action);
>> +
>> +fl_err:
>> +	kfree(fl_action);
>> +
>> +	return err;
>> +}
>> +
>> +int tcf_action_offload_del(struct tc_action *action) {
>> +	struct flow_offload_action fl_act;
>> +	int err = 0;
>> +
>> +	if (!action)
>> +		return -EINVAL;
>> +
>> +	err = flow_action_init(&fl_act, action, FLOW_ACT_DESTROY, NULL);
>> +	if (err)
>> +		return err;
>> +
>> +	return tcf_action_offload_cmd(&fl_act, NULL); }
>> +
>>   /* Returns numbers of initialized actions or negative error. */
>>
>>   int tcf_action_init(struct net *net, struct tcf_proto *tp, struct
>> nlattr *nla, @@ -1103,6 +1267,8 @@ int tcf_action_init(struct net *net,
>struct tcf_proto *tp, struct nlattr *nla,
>>   		sz += tcf_action_fill_size(act);
>>   		/* Start from index 0 */
>>   		actions[i - 1] = act;
>> +		if (!(flags & TCA_ACT_FLAGS_BIND))
>> +			tcf_action_offload_add(act, extack);
>
>Why is this restricted to actions created without the TCA_ACT_FLAGS_BIND
>flag?
>How are actions instantiated by the filters different from those that are
>created by "tc actions"?
>
Our patch aims to offload tc action that is created independent of any flow. It is usually
offloaded when it is added or replaced. 
This patch is to implement a process of reoffloading the actions when driver is
inserted or removed, so it will still offload the independent actions. 
>>   	}
>>
>>   	/* We have to commit them all together, because if any error
>> happened in diff --git a/net/sched/cls_api.c b/net/sched/cls_api.c
>> index 2ef8f5a6205a..351d93988b8b 100644
>> --- a/net/sched/cls_api.c
>> +++ b/net/sched/cls_api.c
>> @@ -3544,8 +3544,8 @@ static enum flow_action_hw_stats
>tc_act_hw_stats(u8 hw_stats)
>>   	return hw_stats;
>>   }
>>
>> -int tc_setup_flow_action(struct flow_action *flow_action,
>> -			 const struct tcf_exts *exts)
>> +int tc_setup_action(struct flow_action *flow_action,
>> +		    struct tc_action *actions[])
>>   {
>>   	struct tc_action *act;
>>   	int i, j, k, err = 0;
>> @@ -3554,11 +3554,11 @@ int tc_setup_flow_action(struct flow_action
>*flow_action,
>>   	BUILD_BUG_ON(TCA_ACT_HW_STATS_IMMEDIATE !=
>FLOW_ACTION_HW_STATS_IMMEDIATE);
>>   	BUILD_BUG_ON(TCA_ACT_HW_STATS_DELAYED !=
>> FLOW_ACTION_HW_STATS_DELAYED);
>>
>> -	if (!exts)
>> +	if (!actions)
>>   		return 0;
>>
>>   	j = 0;
>> -	tcf_exts_for_each_action(i, act, exts) {
>> +	tcf_act_for_each_action(i, act, actions) {
>>   		struct flow_action_entry *entry;
>>
>>   		entry = &flow_action->entries[j];
>> @@ -3725,7 +3725,19 @@ int tc_setup_flow_action(struct flow_action
>*flow_action,
>>   	spin_unlock_bh(&act->tcfa_lock);
>>   	goto err_out;
>>   }
>> +EXPORT_SYMBOL(tc_setup_action);
>> +
>> +#ifdef CONFIG_NET_CLS_ACT
>> +int tc_setup_flow_action(struct flow_action *flow_action,
>> +			 const struct tcf_exts *exts)
>> +{
>> +	if (!exts)
>> +		return 0;
>> +
>> +	return tc_setup_action(flow_action, exts->actions); }
>>   EXPORT_SYMBOL(tc_setup_flow_action);
>> +#endif
>>
>>   unsigned int tcf_exts_num_actions(struct tcf_exts *exts)
>>   {
>> @@ -3743,6 +3755,15 @@ unsigned int tcf_exts_num_actions(struct
>tcf_exts *exts)
>>   }
>>   EXPORT_SYMBOL(tcf_exts_num_actions);
>>
>> +unsigned int tcf_act_num_actions_single(struct tc_action *act) {
>> +	if (is_tcf_pedit(act))
>> +		return tcf_pedit_nkeys(act);
>> +	else
>> +		return 1;
>> +}
>> +EXPORT_SYMBOL(tcf_act_num_actions_single);
>> +
>>   #ifdef CONFIG_NET_CLS_ACT
>>   static int tcf_qevent_parse_block_index(struct nlattr *block_index_attr,
>>   					u32 *p_block_index,
>>

Powered by blists - more mailing lists