/* * Copyright (c) 2016 Cisco and/or its affiliates. * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at: * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ /** * \brief * The load-balance object represents an ECMP choice. The buckets of a load * balance object point to the sub-graph after the choice is made. * THe load-balance object is also object type returned from a FIB table lookup. * As such it needs to represent the case where there is only one coice. It may * seem like overkill to use a load-balance object in this case, but the reason * is for performance. If the load-balance object were not the result of the FIB * lookup, then some other object would be. The case where there was ECMP * this other object would need a load-balance as a parent and hence just add * an unnecessary indirection. * * It is also the object in the DP that represents a via-fib-entry in a recursive * route. * */ #ifndef __LOAD_BALANCE_H__ #define __LOAD_BALANCE_H__ #include <vlib/vlib.h> #include <vnet/ip/lookup.h> #include <vnet/dpo/dpo.h> #include <vnet/fib/fib_types.h> #include <vnet/fib/fib_entry.h> /** * Load-balance main */ typedef struct load_balance_main_t_ { vlib_combined_counter_main_t lbm_to_counters; vlib_combined_counter_main_t lbm_via_counters; } load_balance_main_t; extern load_balance_main_t load_balance_main; /** * The number of buckets that a load-balance object can have and still * fit in one cache-line */ #define LB_NUM_INLINE_BUCKETS 4 /** * @brief One path from an [EU]CMP set that the client wants to add to a * load-balance object */ typedef struct load_balance_path_t_ { /** * ID of the Data-path object. */ dpo_id_t path_dpo; /** * The index of the FIB path */ fib_node_index_t path_index; /** * weight for the path. */ u32 path_weight; } load_balance_path_t; /** * Flags controlling load-balance creation and modification */ typedef enum load_balance_attr_t_ { LOAD_BALANCE_ATTR_USES_MAP = 0, LOAD_BALANCE_ATTR_STICKY = 1, } load_balance_attr_t; #define LOAD_BALANCE_ATTR_NAMES { \ [LOAD_BALANCE_ATTR_USES_MAP] = "uses-map", \ [LOAD_BALANCE_ATTR_STICKY] = "sticky", \ } #define FOR_EACH_LOAD_BALANCE_ATTR(_attr) \ for (_attr = 0; _attr <= LOAD_BALANCE_ATTR_STICKY; _attr++) typedef enum load_balance_flags_t_ { LOAD_BALANCE_FLAG_NONE = 0, LOAD_BALANCE_FLAG_USES_MAP = (1 << 0), LOAD_BALANCE_FLAG_STICKY = (1 << 1), } __attribute__((packed)) load_balance_flags_t; /** * The FIB DPO provieds; * - load-balancing over the next DPOs in the chain/graph * - per-route counters */ typedef struct load_balance_t_ { /** * required for pool_get_aligned. * memebers used in the switch path come first! */ CLIB_CACHE_LINE_ALIGN_MARK(cacheline0); /** * number of buckets in the load-balance. always a power of 2. */ u16 lb_n_buckets; /** * number of buckets in the load-balance - 1. used in the switch path * as part of the hash calculation. */ u16 lb_n_buckets_minus_1; /** * The protocol of packets that traverse this LB. * need in combination with the flow hash config to determine how to hash. * u8. */ dpo_proto_t lb_proto; /** * Flags concenring the LB's creation and modification */ load_balance_flags_t lb_flags; /** * Flags from the load-balance's associated fib_entry_t */ fib_entry_flag_t lb_fib_entry_flags; /** * The number of locks, which is approximately the number of users, * of this load-balance. * Load-balance objects of via-entries are heavily shared by recursives, * so the lock count is a u32. */ u32 lb_locks; /** * index of the load-balance map, INVALID if this LB does not use one */ index_t lb_map; /** * This is the index of the uRPF list for this LB */ index_t lb_urpf; /** * the hash config to use when selecting a bucket. this is a u16 */ flow_hash_config_t lb_hash_config; /** * Vector of buckets containing the next DPOs, sized as lbo_num */ dpo_id_t *lb_buckets; /** * The rest of the cache line is used for buckets. In the common case * where there there are less than 4 buckets, then the buckets are * on the same cachlie and we save ourselves a pointer dereferance in * the data-path. */ dpo_id_t lb_buckets_inline[LB_NUM_INLINE_BUCKETS]; } load_balance_t; STATIC_ASSERT(sizeof(load_balance_t) <= CLIB_CACHE_LINE_BYTES, "A load_balance object size exceeds one cachline"); /** * Flags controlling load-balance formatting/display */ typedef enum load_balance_format_flags_t_ { LOAD_BALANCE_FORMAT_NONE, LOAD_BALANCE_FORMAT_DETAIL = (1 << 0), } load_balance_format_flags_t; extern index_t load_balance_create(u32 num_buckets, dpo_proto_t lb_proto, flow_hash_config_t fhc); extern void load_balance_multipath_update( const dpo_id_t *dpo, const load_balance_path_t * raw_next_hops, load_balance_flags_t flags); extern void load_balance_set_bucket(index_t lbi, u32 bucket, const dpo_id_t *next); extern void load_balance_set_urpf(index_t lbi, index_t urpf); extern void load_balance_set_fib_entry_flags(index_t lbi, fib_entry_flag_t flags); extern index_t load_balance_get_urpf(index_t lbi); extern u8* format_load_balance(u8 * s, va_list * args); extern const dpo_id_t *load_balance_get_bucket(index_t lbi, u32 bucket); extern int load_balance_is_drop(const dpo_id_t *dpo); extern u16 load_balance_n_buckets(index_t lbi); extern f64 load_balance_get_multipath_tolerance(void); /** * The encapsulation breakages are for fast DP access */ extern load_balance_t *load_balance_pool; static inline load_balance_t* load_balance_get (index_t lbi) { return (pool_elt_at_index(load_balance_pool, lbi)); } #define LB_HAS_INLINE_BUCKETS(_lb) \ ((_lb)->lb_n_buckets <= LB_NUM_INLINE_BUCKETS) static inline const dpo_id_t * load_balance_get_bucket_i (const load_balance_t *lb, u32 bucket) { ASSERT(bucket < lb->lb_n_buckets); if (PREDICT_TRUE(LB_HAS_INLINE_BUCKETS(lb))) { return (&lb->lb_buckets_inline[bucket]); } else { return (&lb->lb_buckets[bucket]); } } extern void load_balance_module_init(void); #endif