From 1e8c66198926e4391c7fe67401126776c5e9de3b Mon Sep 17 00:00:00 2001 From: Ido Schimmel Date: Mon, 30 Mar 2020 22:38:18 +0300 Subject: devlink: Add packet trap policers support Devices capable of offloading the kernel's datapath and perform functions such as bridging and routing must also be able to send (trap) specific packets to the kernel (i.e., the CPU) for processing. For example, a device acting as a multicast-aware bridge must be able to trap IGMP membership reports to the kernel for processing by the bridge module. In most cases, the underlying device is capable of handling packet rates that are several orders of magnitude higher compared to those that can be handled by the CPU. Therefore, in order to prevent the underlying device from overwhelming the CPU, devices usually include packet trap policers that are able to police the trapped packets to rates that can be handled by the CPU. This patch allows capable device drivers to register their supported packet trap policers with devlink. User space can then tune the parameters of these policer (currently, rate and burst size) and read from the device the number of packets that were dropped by the policer, if supported. Subsequent patches in the series will allow device drivers to create default binding between these policers and packet trap groups and allow user space to change the binding. v2: * Add 'strict_start_type' in devlink policy * Have device drivers provide max/min rate/burst size for each policer. Use them to check validity of user provided parameters Signed-off-by: Ido Schimmel Reviewed-by: Jiri Pirko Reviewed-by: Jakub Kicinski Signed-off-by: David S. Miller --- include/net/devlink.h | 76 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 76 insertions(+) (limited to 'include/net') diff --git a/include/net/devlink.h b/include/net/devlink.h index 3f5cf62e4de8..9cd08fcfaff7 100644 --- a/include/net/devlink.h +++ b/include/net/devlink.h @@ -35,6 +35,7 @@ struct devlink { struct devlink_dpipe_headers *dpipe_headers; struct list_head trap_list; struct list_head trap_group_list; + struct list_head trap_policer_list; const struct devlink_ops *ops; struct xarray snapshot_ids; struct device *dev; @@ -545,6 +546,29 @@ struct devlink_health_reporter_ops { struct netlink_ext_ack *extack); }; +/** + * struct devlink_trap_policer - Immutable packet trap policer attributes. + * @id: Policer identifier. + * @init_rate: Initial rate in packets / sec. + * @init_burst: Initial burst size in packets. + * @max_rate: Maximum rate. + * @min_rate: Minimum rate. + * @max_burst: Maximum burst size. + * @min_burst: Minimum burst size. + * + * Describes immutable attributes of packet trap policers that drivers register + * with devlink. + */ +struct devlink_trap_policer { + u32 id; + u64 init_rate; + u64 init_burst; + u64 max_rate; + u64 min_rate; + u64 max_burst; + u64 min_burst; +}; + /** * struct devlink_trap_group - Immutable packet trap group attributes. * @name: Trap group name. @@ -742,6 +766,18 @@ enum devlink_trap_group_generic_id { .generic = true, \ } +#define DEVLINK_TRAP_POLICER(_id, _rate, _burst, _max_rate, _min_rate, \ + _max_burst, _min_burst) \ + { \ + .id = _id, \ + .init_rate = _rate, \ + .init_burst = _burst, \ + .max_rate = _max_rate, \ + .min_rate = _min_rate, \ + .max_burst = _max_burst, \ + .min_burst = _min_burst, \ + } + struct devlink_ops { int (*reload_down)(struct devlink *devlink, bool netns_change, struct netlink_ext_ack *extack); @@ -838,6 +874,38 @@ struct devlink_ops { */ int (*trap_group_init)(struct devlink *devlink, const struct devlink_trap_group *group); + /** + * @trap_policer_init: Trap policer initialization function. + * + * Should be used by device drivers to initialize the trap policer in + * the underlying device. + */ + int (*trap_policer_init)(struct devlink *devlink, + const struct devlink_trap_policer *policer); + /** + * @trap_policer_fini: Trap policer de-initialization function. + * + * Should be used by device drivers to de-initialize the trap policer + * in the underlying device. + */ + void (*trap_policer_fini)(struct devlink *devlink, + const struct devlink_trap_policer *policer); + /** + * @trap_policer_set: Trap policer parameters set function. + */ + int (*trap_policer_set)(struct devlink *devlink, + const struct devlink_trap_policer *policer, + u64 rate, u64 burst, + struct netlink_ext_ack *extack); + /** + * @trap_policer_counter_get: Trap policer counter get function. + * + * Should be used by device drivers to report number of packets dropped + * by the policer. + */ + int (*trap_policer_counter_get)(struct devlink *devlink, + const struct devlink_trap_policer *policer, + u64 *p_drops); }; static inline void *devlink_priv(struct devlink *devlink) @@ -1080,6 +1148,14 @@ int devlink_trap_groups_register(struct devlink *devlink, void devlink_trap_groups_unregister(struct devlink *devlink, const struct devlink_trap_group *groups, size_t groups_count); +int +devlink_trap_policers_register(struct devlink *devlink, + const struct devlink_trap_policer *policers, + size_t policers_count); +void +devlink_trap_policers_unregister(struct devlink *devlink, + const struct devlink_trap_policer *policers, + size_t policers_count); #if IS_ENABLED(CONFIG_NET_DEVLINK) -- cgit v1.2.3 From f9f54392d2c88b34a2aaa6e51b202b3fd9c984b4 Mon Sep 17 00:00:00 2001 From: Ido Schimmel Date: Mon, 30 Mar 2020 22:38:21 +0300 Subject: devlink: Add packet trap group parameters support Packet trap groups are used to aggregate logically related packet traps. Currently, these groups allow user space to batch operations such as setting the trap action of all member traps. In order to prevent the CPU from being overwhelmed by too many trapped packets, it is desirable to bind a packet trap policer to these groups. For example, to limit all the packets that encountered an exception during routing to 10Kpps. Allow device drivers to bind default packet trap policers to packet trap groups when the latter are registered with devlink. The next patch will enable user space to change this default binding. Signed-off-by: Ido Schimmel Reviewed-by: Jiri Pirko Reviewed-by: Jakub Kicinski Signed-off-by: David S. Miller --- .../net/ethernet/mellanox/mlxsw/spectrum_trap.c | 8 +++--- drivers/net/netdevsim/dev.c | 8 +++--- include/net/devlink.h | 5 +++- net/core/devlink.c | 31 ++++++++++++++++++++++ 4 files changed, 43 insertions(+), 9 deletions(-) (limited to 'include/net') diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_trap.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_trap.c index 727f6ef243df..24f15345ba84 100644 --- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_trap.c +++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_trap.c @@ -166,10 +166,10 @@ static void mlxsw_sp_rx_exception_listener(struct sk_buff *skb, u8 local_port, _action, false, SP_##_group_id, SET_FW_DEFAULT) static const struct devlink_trap_group mlxsw_sp_trap_groups_arr[] = { - DEVLINK_TRAP_GROUP_GENERIC(L2_DROPS), - DEVLINK_TRAP_GROUP_GENERIC(L3_DROPS), - DEVLINK_TRAP_GROUP_GENERIC(TUNNEL_DROPS), - DEVLINK_TRAP_GROUP_GENERIC(ACL_DROPS), + DEVLINK_TRAP_GROUP_GENERIC(L2_DROPS, 0), + DEVLINK_TRAP_GROUP_GENERIC(L3_DROPS, 0), + DEVLINK_TRAP_GROUP_GENERIC(TUNNEL_DROPS, 0), + DEVLINK_TRAP_GROUP_GENERIC(ACL_DROPS, 0), }; static const struct devlink_trap mlxsw_sp_traps_arr[] = { diff --git a/drivers/net/netdevsim/dev.c b/drivers/net/netdevsim/dev.c index 21341e592467..bda603cfe66a 100644 --- a/drivers/net/netdevsim/dev.c +++ b/drivers/net/netdevsim/dev.c @@ -452,10 +452,10 @@ static const struct devlink_trap_policer nsim_trap_policers_arr[] = { }; static const struct devlink_trap_group nsim_trap_groups_arr[] = { - DEVLINK_TRAP_GROUP_GENERIC(L2_DROPS), - DEVLINK_TRAP_GROUP_GENERIC(L3_DROPS), - DEVLINK_TRAP_GROUP_GENERIC(BUFFER_DROPS), - DEVLINK_TRAP_GROUP_GENERIC(ACL_DROPS), + DEVLINK_TRAP_GROUP_GENERIC(L2_DROPS, 0), + DEVLINK_TRAP_GROUP_GENERIC(L3_DROPS, 1), + DEVLINK_TRAP_GROUP_GENERIC(BUFFER_DROPS, 2), + DEVLINK_TRAP_GROUP_GENERIC(ACL_DROPS, 3), }; static const struct devlink_trap nsim_traps_arr[] = { diff --git a/include/net/devlink.h b/include/net/devlink.h index 9cd08fcfaff7..63834686c8d3 100644 --- a/include/net/devlink.h +++ b/include/net/devlink.h @@ -574,6 +574,7 @@ struct devlink_trap_policer { * @name: Trap group name. * @id: Trap group identifier. * @generic: Whether the trap group is generic or not. + * @init_policer_id: Initial policer identifier. * * Describes immutable attributes of packet trap groups that drivers register * with devlink. @@ -582,6 +583,7 @@ struct devlink_trap_group { const char *name; u16 id; bool generic; + u32 init_policer_id; }; #define DEVLINK_TRAP_METADATA_TYPE_F_IN_PORT BIT(0) @@ -759,11 +761,12 @@ enum devlink_trap_group_generic_id { .metadata_cap = _metadata_cap, \ } -#define DEVLINK_TRAP_GROUP_GENERIC(_id) \ +#define DEVLINK_TRAP_GROUP_GENERIC(_id, _policer_id) \ { \ .name = DEVLINK_TRAP_GROUP_GENERIC_NAME_##_id, \ .id = DEVLINK_TRAP_GROUP_GENERIC_ID_##_id, \ .generic = true, \ + .init_policer_id = _policer_id, \ } #define DEVLINK_TRAP_POLICER(_id, _rate, _burst, _max_rate, _min_rate, \ diff --git a/net/core/devlink.c b/net/core/devlink.c index e22b8ed67bf7..544543443e96 100644 --- a/net/core/devlink.c +++ b/net/core/devlink.c @@ -5739,6 +5739,7 @@ struct devlink_trap_policer_item { /** * struct devlink_trap_group_item - Packet trap group attributes. * @group: Immutable packet trap group attributes. + * @policer_item: Associated policer item. Can be NULL. * @list: trap_group_list member. * @stats: Trap group statistics. * @@ -5747,6 +5748,7 @@ struct devlink_trap_policer_item { */ struct devlink_trap_group_item { const struct devlink_trap_group *group; + struct devlink_trap_policer_item *policer_item; struct list_head list; struct devlink_stats __percpu *stats; }; @@ -6161,6 +6163,11 @@ devlink_nl_trap_group_fill(struct sk_buff *msg, struct devlink *devlink, nla_put_flag(msg, DEVLINK_ATTR_TRAP_GENERIC)) goto nla_put_failure; + if (group_item->policer_item && + nla_put_u32(msg, DEVLINK_ATTR_TRAP_POLICER_ID, + group_item->policer_item->policer->id)) + goto nla_put_failure; + err = devlink_trap_stats_put(msg, group_item->stats); if (err) goto nla_put_failure; @@ -8759,6 +8766,25 @@ void *devlink_trap_ctx_priv(void *trap_ctx) } EXPORT_SYMBOL_GPL(devlink_trap_ctx_priv); +static int +devlink_trap_group_item_policer_link(struct devlink *devlink, + struct devlink_trap_group_item *group_item) +{ + u32 policer_id = group_item->group->init_policer_id; + struct devlink_trap_policer_item *policer_item; + + if (policer_id == 0) + return 0; + + policer_item = devlink_trap_policer_item_lookup(devlink, policer_id); + if (WARN_ON_ONCE(!policer_item)) + return -EINVAL; + + group_item->policer_item = policer_item; + + return 0; +} + static int devlink_trap_group_register(struct devlink *devlink, const struct devlink_trap_group *group) @@ -8781,6 +8807,10 @@ devlink_trap_group_register(struct devlink *devlink, group_item->group = group; + err = devlink_trap_group_item_policer_link(devlink, group_item); + if (err) + goto err_policer_link; + if (devlink->ops->trap_group_init) { err = devlink->ops->trap_group_init(devlink, group); if (err) @@ -8794,6 +8824,7 @@ devlink_trap_group_register(struct devlink *devlink, return 0; err_group_init: +err_policer_link: free_percpu(group_item->stats); err_stats_alloc: kfree(group_item); -- cgit v1.2.3 From c064875a63528e8ebcefc0ae450ed0fd904d08c4 Mon Sep 17 00:00:00 2001 From: Ido Schimmel Date: Mon, 30 Mar 2020 22:38:22 +0300 Subject: devlink: Allow setting of packet trap group parameters The previous patch allowed device drivers to publish their default binding between packet trap policers and packet trap groups. However, some users might not be content with this binding and would like to change it. In case user space passed a packet trap policer identifier when setting a packet trap group, invoke the appropriate device driver callback and pass the new policer identifier. v2: * Check for presence of 'DEVLINK_ATTR_TRAP_POLICER_ID' in devlink_trap_group_set() and bail if not present * Add extack error message in case trap group was partially modified Signed-off-by: Ido Schimmel Reviewed-by: Jiri Pirko Acked-by: Jakub Kicinski Signed-off-by: David S. Miller --- include/net/devlink.h | 9 +++++++++ net/core/devlink.c | 56 +++++++++++++++++++++++++++++++++++++++++++++++++-- 2 files changed, 63 insertions(+), 2 deletions(-) (limited to 'include/net') diff --git a/include/net/devlink.h b/include/net/devlink.h index 63834686c8d3..8ffc1b5cd89b 100644 --- a/include/net/devlink.h +++ b/include/net/devlink.h @@ -877,6 +877,15 @@ struct devlink_ops { */ int (*trap_group_init)(struct devlink *devlink, const struct devlink_trap_group *group); + /** + * @trap_group_set: Trap group parameters set function. + * + * Note: @policer can be NULL when a policer is being unbound from + * @group. + */ + int (*trap_group_set)(struct devlink *devlink, + const struct devlink_trap_group *group, + const struct devlink_trap_policer *policer); /** * @trap_policer_init: Trap policer initialization function. * diff --git a/net/core/devlink.c b/net/core/devlink.c index 544543443e96..80f97722f31f 100644 --- a/net/core/devlink.c +++ b/net/core/devlink.c @@ -6283,7 +6283,7 @@ __devlink_trap_group_action_set(struct devlink *devlink, static int devlink_trap_group_action_set(struct devlink *devlink, struct devlink_trap_group_item *group_item, - struct genl_info *info) + struct genl_info *info, bool *p_modified) { enum devlink_trap_action trap_action; int err; @@ -6302,6 +6302,47 @@ devlink_trap_group_action_set(struct devlink *devlink, if (err) return err; + *p_modified = true; + + return 0; +} + +static int devlink_trap_group_set(struct devlink *devlink, + struct devlink_trap_group_item *group_item, + struct genl_info *info) +{ + struct devlink_trap_policer_item *policer_item; + struct netlink_ext_ack *extack = info->extack; + const struct devlink_trap_policer *policer; + struct nlattr **attrs = info->attrs; + int err; + + if (!attrs[DEVLINK_ATTR_TRAP_POLICER_ID]) + return 0; + + if (!devlink->ops->trap_group_set) + return -EOPNOTSUPP; + + policer_item = group_item->policer_item; + if (attrs[DEVLINK_ATTR_TRAP_POLICER_ID]) { + u32 policer_id; + + policer_id = nla_get_u32(attrs[DEVLINK_ATTR_TRAP_POLICER_ID]); + policer_item = devlink_trap_policer_item_lookup(devlink, + policer_id); + if (policer_id && !policer_item) { + NL_SET_ERR_MSG_MOD(extack, "Device did not register this trap policer"); + return -ENOENT; + } + } + policer = policer_item ? policer_item->policer : NULL; + + err = devlink->ops->trap_group_set(devlink, group_item->group, policer); + if (err) + return err; + + group_item->policer_item = policer_item; + return 0; } @@ -6311,6 +6352,7 @@ static int devlink_nl_cmd_trap_group_set_doit(struct sk_buff *skb, struct netlink_ext_ack *extack = info->extack; struct devlink *devlink = info->user_ptr[0]; struct devlink_trap_group_item *group_item; + bool modified = false; int err; if (list_empty(&devlink->trap_group_list)) @@ -6322,11 +6364,21 @@ static int devlink_nl_cmd_trap_group_set_doit(struct sk_buff *skb, return -ENOENT; } - err = devlink_trap_group_action_set(devlink, group_item, info); + err = devlink_trap_group_action_set(devlink, group_item, info, + &modified); if (err) return err; + err = devlink_trap_group_set(devlink, group_item, info); + if (err) + goto err_trap_group_set; + return 0; + +err_trap_group_set: + if (modified) + NL_SET_ERR_MSG_MOD(extack, "Trap group set failed, but some changes were committed already"); + return err; } static struct devlink_trap_policer_item * -- cgit v1.2.3