diff options
Diffstat (limited to 'src/vnet/dpo/load_balance.c')
| -rw-r--r-- | src/vnet/dpo/load_balance.c | 993 |
1 files changed, 993 insertions, 0 deletions
diff --git a/src/vnet/dpo/load_balance.c b/src/vnet/dpo/load_balance.c new file mode 100644 index 00000000000..a244776ffb8 --- /dev/null +++ b/src/vnet/dpo/load_balance.c @@ -0,0 +1,993 @@ +/* + * 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. + */ + +#include <vnet/ip/lookup.h> +#include <vnet/dpo/load_balance.h> +#include <vnet/dpo/load_balance_map.h> +#include <vnet/dpo/drop_dpo.h> +#include <vppinfra/math.h> /* for fabs */ +#include <vnet/adj/adj.h> +#include <vnet/adj/adj_internal.h> +#include <vnet/fib/fib_urpf_list.h> + +/* + * distribution error tolerance for load-balancing + */ +const f64 multipath_next_hop_error_tolerance = 0.1; + +#undef LB_DEBUG + +#ifdef LB_DEBUG +#define LB_DBG(_lb, _fmt, _args...) \ +{ \ + u8* _tmp =NULL; \ + clib_warning("lb:[%s]:" _fmt, \ + load_balance_format(load_balance_get_index((_lb)), \ + 0, _tmp), \ + ##_args); \ + vec_free(_tmp); \ +} +#else +#define LB_DBG(_p, _fmt, _args...) +#endif + + +/** + * Pool of all DPOs. It's not static so the DP can have fast access + */ +load_balance_t *load_balance_pool; + +/** + * The one instance of load-balance main + */ +load_balance_main_t load_balance_main; + +f64 +load_balance_get_multipath_tolerance (void) +{ + return (multipath_next_hop_error_tolerance); +} + +static inline index_t +load_balance_get_index (const load_balance_t *lb) +{ + return (lb - load_balance_pool); +} + +static inline dpo_id_t* +load_balance_get_buckets (load_balance_t *lb) +{ + if (LB_HAS_INLINE_BUCKETS(lb)) + { + return (lb->lb_buckets_inline); + } + else + { + return (lb->lb_buckets); + } +} + +static load_balance_t * +load_balance_alloc_i (void) +{ + load_balance_t *lb; + + pool_get_aligned(load_balance_pool, lb, CLIB_CACHE_LINE_BYTES); + memset(lb, 0, sizeof(*lb)); + + lb->lb_map = INDEX_INVALID; + lb->lb_urpf = INDEX_INVALID; + vlib_validate_combined_counter(&(load_balance_main.lbm_to_counters), + load_balance_get_index(lb)); + vlib_validate_combined_counter(&(load_balance_main.lbm_via_counters), + load_balance_get_index(lb)); + vlib_zero_combined_counter(&(load_balance_main.lbm_to_counters), + load_balance_get_index(lb)); + vlib_zero_combined_counter(&(load_balance_main.lbm_via_counters), + load_balance_get_index(lb)); + + return (lb); +} + +static u8* +load_balance_format (index_t lbi, + load_balance_format_flags_t flags, + u32 indent, + u8 *s) +{ + vlib_counter_t to, via; + load_balance_t *lb; + dpo_id_t *buckets; + u32 i; + + lb = load_balance_get(lbi); + vlib_get_combined_counter(&(load_balance_main.lbm_to_counters), lbi, &to); + vlib_get_combined_counter(&(load_balance_main.lbm_via_counters), lbi, &via); + buckets = load_balance_get_buckets(lb); + + s = format(s, "%U: ", format_dpo_type, DPO_LOAD_BALANCE); + s = format(s, "[index:%d buckets:%d ", lbi, lb->lb_n_buckets); + s = format(s, "uRPF:%d ", lb->lb_urpf); + s = format(s, "to:[%Ld:%Ld]", to.packets, to.bytes); + if (0 != via.packets) + { + s = format(s, " via:[%Ld:%Ld]", + via.packets, via.bytes); + } + s = format(s, "]"); + + if (INDEX_INVALID != lb->lb_map) + { + s = format(s, "\n%U%U", + format_white_space, indent+4, + format_load_balance_map, lb->lb_map, indent+4); + } + for (i = 0; i < lb->lb_n_buckets; i++) + { + s = format(s, "\n%U[%d] %U", + format_white_space, indent+2, + i, + format_dpo_id, + &buckets[i], indent+6); + } + return (s); +} + +u8* +format_load_balance (u8 * s, va_list * args) +{ + index_t lbi = va_arg(*args, index_t); + load_balance_format_flags_t flags = va_arg(*args, load_balance_format_flags_t); + + return (load_balance_format(lbi, flags, 0, s)); +} +static u8* +format_load_balance_dpo (u8 * s, va_list * args) +{ + index_t lbi = va_arg(*args, index_t); + u32 indent = va_arg(*args, u32); + + return (load_balance_format(lbi, LOAD_BALANCE_FORMAT_DETAIL, indent, s)); +} + + +static load_balance_t * +load_balance_create_i (u32 num_buckets, + dpo_proto_t lb_proto, + flow_hash_config_t fhc) +{ + load_balance_t *lb; + + lb = load_balance_alloc_i(); + lb->lb_hash_config = fhc; + lb->lb_n_buckets = num_buckets; + lb->lb_n_buckets_minus_1 = num_buckets-1; + lb->lb_proto = lb_proto; + + if (!LB_HAS_INLINE_BUCKETS(lb)) + { + vec_validate_aligned(lb->lb_buckets, + lb->lb_n_buckets - 1, + CLIB_CACHE_LINE_BYTES); + } + + LB_DBG(lb, "create"); + + return (lb); +} + +index_t +load_balance_create (u32 n_buckets, + dpo_proto_t lb_proto, + flow_hash_config_t fhc) +{ + return (load_balance_get_index(load_balance_create_i(n_buckets, lb_proto, fhc))); +} + +static inline void +load_balance_set_bucket_i (load_balance_t *lb, + u32 bucket, + dpo_id_t *buckets, + const dpo_id_t *next) +{ + dpo_stack(DPO_LOAD_BALANCE, lb->lb_proto, &buckets[bucket], next); +} + +void +load_balance_set_bucket (index_t lbi, + u32 bucket, + const dpo_id_t *next) +{ + load_balance_t *lb; + dpo_id_t *buckets; + + lb = load_balance_get(lbi); + buckets = load_balance_get_buckets(lb); + + ASSERT(bucket < lb->lb_n_buckets); + + load_balance_set_bucket_i(lb, bucket, buckets, next); +} + +int +load_balance_is_drop (const dpo_id_t *dpo) +{ + load_balance_t *lb; + + if (DPO_LOAD_BALANCE != dpo->dpoi_type) + return (0); + + lb = load_balance_get(dpo->dpoi_index); + + if (1 == lb->lb_n_buckets) + { + return (dpo_is_drop(load_balance_get_bucket_i(lb, 0))); + } + return (0); +} + +void +load_balance_set_urpf (index_t lbi, + index_t urpf) +{ + load_balance_t *lb; + index_t old; + + lb = load_balance_get(lbi); + + /* + * packets in flight we see this change. but it's atomic, so :P + */ + old = lb->lb_urpf; + lb->lb_urpf = urpf; + + fib_urpf_list_unlock(old); + fib_urpf_list_lock(urpf); +} + +index_t +load_balance_get_urpf (index_t lbi) +{ + load_balance_t *lb; + + lb = load_balance_get(lbi); + + return (lb->lb_urpf); +} + +const dpo_id_t * +load_balance_get_bucket (index_t lbi, + u32 bucket) +{ + load_balance_t *lb; + + lb = load_balance_get(lbi); + + return (load_balance_get_bucket_i(lb, bucket)); +} + +static int +next_hop_sort_by_weight (load_balance_path_t * n1, + load_balance_path_t * n2) +{ + return ((int) n1->path_weight - (int) n2->path_weight); +} + +/* Given next hop vector is over-written with normalized one with sorted weights and + with weights corresponding to the number of adjacencies for each next hop. + Returns number of adjacencies in block. */ +u32 +ip_multipath_normalize_next_hops (load_balance_path_t * raw_next_hops, + load_balance_path_t ** normalized_next_hops, + u32 *sum_weight_in, + f64 multipath_next_hop_error_tolerance) +{ + load_balance_path_t * nhs; + uword n_nhs, n_adj, n_adj_left, i, sum_weight; + f64 norm, error; + + n_nhs = vec_len (raw_next_hops); + ASSERT (n_nhs > 0); + if (n_nhs == 0) + return 0; + + /* Allocate enough space for 2 copies; we'll use second copy to save original weights. */ + nhs = *normalized_next_hops; + vec_validate (nhs, 2*n_nhs - 1); + + /* Fast path: 1 next hop in block. */ + n_adj = n_nhs; + if (n_nhs == 1) + { + nhs[0] = raw_next_hops[0]; + nhs[0].path_weight = 1; + _vec_len (nhs) = 1; + sum_weight = 1; + goto done; + } + + else if (n_nhs == 2) + { + int cmp = next_hop_sort_by_weight (&raw_next_hops[0], &raw_next_hops[1]) < 0; + + /* Fast sort. */ + nhs[0] = raw_next_hops[cmp]; + nhs[1] = raw_next_hops[cmp ^ 1]; + + /* Fast path: equal cost multipath with 2 next hops. */ + if (nhs[0].path_weight == nhs[1].path_weight) + { + nhs[0].path_weight = nhs[1].path_weight = 1; + _vec_len (nhs) = 2; + sum_weight = 2; + goto done; + } + } + else + { + clib_memcpy (nhs, raw_next_hops, n_nhs * sizeof (raw_next_hops[0])); + qsort (nhs, n_nhs, sizeof (nhs[0]), (void *) next_hop_sort_by_weight); + } + + /* Find total weight to normalize weights. */ + sum_weight = 0; + for (i = 0; i < n_nhs; i++) + sum_weight += nhs[i].path_weight; + + /* In the unlikely case that all weights are given as 0, set them all to 1. */ + if (sum_weight == 0) + { + for (i = 0; i < n_nhs; i++) + nhs[i].path_weight = 1; + sum_weight = n_nhs; + } + + /* Save copies of all next hop weights to avoid being overwritten in loop below. */ + for (i = 0; i < n_nhs; i++) + nhs[n_nhs + i].path_weight = nhs[i].path_weight; + + /* Try larger and larger power of 2 sized adjacency blocks until we + find one where traffic flows to within 1% of specified weights. */ + for (n_adj = max_pow2 (n_nhs); ; n_adj *= 2) + { + error = 0; + + norm = n_adj / ((f64) sum_weight); + n_adj_left = n_adj; + for (i = 0; i < n_nhs; i++) + { + f64 nf = nhs[n_nhs + i].path_weight * norm; /* use saved weights */ + word n = flt_round_nearest (nf); + + n = n > n_adj_left ? n_adj_left : n; + n_adj_left -= n; + error += fabs (nf - n); + nhs[i].path_weight = n; + + if (0 == nhs[i].path_weight) + { + /* + * when the weight skew is high (norm is small) and n == nf. + * without this correction the path with a low weight would have + * no represenation in the load-balanace - don't want that. + * If the weight skew is high so the load-balance has many buckets + * to allow it. pays ya money takes ya choice. + */ + error = n_adj; + break; + } + } + + nhs[0].path_weight += n_adj_left; + + /* Less than 5% average error per adjacency with this size adjacency block? */ + if (error <= multipath_next_hop_error_tolerance*n_adj) + { + /* Truncate any next hops with zero weight. */ + _vec_len (nhs) = i; + break; + } + } + +done: + /* Save vector for next call. */ + *normalized_next_hops = nhs; + *sum_weight_in = sum_weight; + return n_adj; +} + +static load_balance_path_t * +load_balance_multipath_next_hop_fixup (load_balance_path_t *nhs, + dpo_proto_t drop_proto) +{ + if (0 == vec_len(nhs)) + { + load_balance_path_t *nh; + + /* + * we need something for the load-balance. so use the drop + */ + vec_add2(nhs, nh, 1); + + nh->path_weight = 1; + dpo_copy(&nh->path_dpo, drop_dpo_get(drop_proto)); + } + + return (nhs); +} + +/* + * Fill in adjacencies in block based on corresponding + * next hop adjacencies. + */ +static void +load_balance_fill_buckets (load_balance_t *lb, + load_balance_path_t *nhs, + dpo_id_t *buckets, + u32 n_buckets) +{ + load_balance_path_t * nh; + u16 ii, bucket; + + bucket = 0; + + /* + * the next-hops have normalised weights. that means their sum is the number + * of buckets we need to fill. + */ + vec_foreach (nh, nhs) + { + for (ii = 0; ii < nh->path_weight; ii++) + { + ASSERT(bucket < n_buckets); + load_balance_set_bucket_i(lb, bucket++, buckets, &nh->path_dpo); + } + } +} + +static inline void +load_balance_set_n_buckets (load_balance_t *lb, + u32 n_buckets) +{ + lb->lb_n_buckets = n_buckets; + lb->lb_n_buckets_minus_1 = n_buckets-1; +} + +void +load_balance_multipath_update (const dpo_id_t *dpo, + load_balance_path_t * raw_next_hops, + load_balance_flags_t flags) +{ + u32 sum_of_weights,n_buckets, ii; + load_balance_path_t * nh, * nhs; + index_t lbmi, old_lbmi; + load_balance_t *lb; + dpo_id_t *tmp_dpo; + + nhs = NULL; + + ASSERT(DPO_LOAD_BALANCE == dpo->dpoi_type); + lb = load_balance_get(dpo->dpoi_index); + raw_next_hops = + load_balance_multipath_next_hop_fixup(raw_next_hops, + lb->lb_proto); + n_buckets = + ip_multipath_normalize_next_hops(raw_next_hops, + &nhs, + &sum_of_weights, + multipath_next_hop_error_tolerance); + + ASSERT (n_buckets >= vec_len (raw_next_hops)); + + /* + * Save the old load-balance map used, and get a new one if required. + */ + old_lbmi = lb->lb_map; + if (flags & LOAD_BALANCE_FLAG_USES_MAP) + { + lbmi = load_balance_map_add_or_lock(n_buckets, sum_of_weights, nhs); + } + else + { + lbmi = INDEX_INVALID; + } + + if (0 == lb->lb_n_buckets) + { + /* + * first time initialisation. no packets inflight, so we can write + * at leisure. + */ + load_balance_set_n_buckets(lb, n_buckets); + + if (!LB_HAS_INLINE_BUCKETS(lb)) + vec_validate_aligned(lb->lb_buckets, + lb->lb_n_buckets - 1, + CLIB_CACHE_LINE_BYTES); + + load_balance_fill_buckets(lb, nhs, + load_balance_get_buckets(lb), + n_buckets); + lb->lb_map = lbmi; + } + else + { + /* + * This is a modification of an existing load-balance. + * We need to ensure that packets inflight see a consistent state, that + * is the number of reported buckets the LB has (read from + * lb_n_buckets_minus_1) is not more than it actually has. So if the + * number of buckets is increasing, we must update the bucket array first, + * then the reported number. vice-versa if the number of buckets goes down. + */ + if (n_buckets == lb->lb_n_buckets) + { + /* + * no change in the number of buckets. we can simply fill what + * is new over what is old. + */ + load_balance_fill_buckets(lb, nhs, + load_balance_get_buckets(lb), + n_buckets); + lb->lb_map = lbmi; + } + else if (n_buckets > lb->lb_n_buckets) + { + /* + * we have more buckets. the old load-balance map (if there is one) + * will remain valid, i.e. mapping to indices within range, so we + * update it last. + */ + if (n_buckets > LB_NUM_INLINE_BUCKETS && + lb->lb_n_buckets <= LB_NUM_INLINE_BUCKETS) + { + /* + * the new increased number of buckets is crossing the threshold + * from the inline storage to out-line. Alloc the outline buckets + * first, then fixup the number. then reset the inlines. + */ + ASSERT(NULL == lb->lb_buckets); + vec_validate_aligned(lb->lb_buckets, + n_buckets - 1, + CLIB_CACHE_LINE_BYTES); + + load_balance_fill_buckets(lb, nhs, + lb->lb_buckets, + n_buckets); + CLIB_MEMORY_BARRIER(); + load_balance_set_n_buckets(lb, n_buckets); + + CLIB_MEMORY_BARRIER(); + + for (ii = 0; ii < LB_NUM_INLINE_BUCKETS; ii++) + { + dpo_reset(&lb->lb_buckets_inline[ii]); + } + } + else + { + if (n_buckets <= LB_NUM_INLINE_BUCKETS) + { + /* + * we are not crossing the threshold and it's still inline buckets. + * we can write the new on the old.. + */ + load_balance_fill_buckets(lb, nhs, + load_balance_get_buckets(lb), + n_buckets); + CLIB_MEMORY_BARRIER(); + load_balance_set_n_buckets(lb, n_buckets); + } + else + { + /* + * we are not crossing the threshold. We need a new bucket array to + * hold the increased number of choices. + */ + dpo_id_t *new_buckets, *old_buckets, *tmp_dpo; + + new_buckets = NULL; + old_buckets = load_balance_get_buckets(lb); + + vec_validate_aligned(new_buckets, + n_buckets - 1, + CLIB_CACHE_LINE_BYTES); + + load_balance_fill_buckets(lb, nhs, new_buckets, n_buckets); + CLIB_MEMORY_BARRIER(); + lb->lb_buckets = new_buckets; + CLIB_MEMORY_BARRIER(); + load_balance_set_n_buckets(lb, n_buckets); + + vec_foreach(tmp_dpo, old_buckets) + { + dpo_reset(tmp_dpo); + } + vec_free(old_buckets); + } + } + + /* + * buckets fixed. ready for the MAP update. + */ + lb->lb_map = lbmi; + } + else + { + /* + * bucket size shrinkage. + * Any map we have will be based on the old + * larger number of buckets, so will be translating to indices + * out of range. So the new MAP must be installed first. + */ + lb->lb_map = lbmi; + CLIB_MEMORY_BARRIER(); + + + if (n_buckets <= LB_NUM_INLINE_BUCKETS && + lb->lb_n_buckets > LB_NUM_INLINE_BUCKETS) + { + /* + * the new decreased number of buckets is crossing the threshold + * from out-line storage to inline: + * 1 - Fill the inline buckets, + * 2 - fixup the number (and this point the inline buckets are + * used). + * 3 - free the outline buckets + */ + load_balance_fill_buckets(lb, nhs, + lb->lb_buckets_inline, + n_buckets); + CLIB_MEMORY_BARRIER(); + load_balance_set_n_buckets(lb, n_buckets); + CLIB_MEMORY_BARRIER(); + + vec_foreach(tmp_dpo, lb->lb_buckets) + { + dpo_reset(tmp_dpo); + } + vec_free(lb->lb_buckets); + } + else + { + /* + * not crossing the threshold. + * 1 - update the number to the smaller size + * 2 - write the new buckets + * 3 - reset those no longer used. + */ + dpo_id_t *buckets; + u32 old_n_buckets; + + old_n_buckets = lb->lb_n_buckets; + buckets = load_balance_get_buckets(lb); + + load_balance_set_n_buckets(lb, n_buckets); + CLIB_MEMORY_BARRIER(); + + load_balance_fill_buckets(lb, nhs, + buckets, + n_buckets); + + for (ii = old_n_buckets-n_buckets; ii < old_n_buckets; ii++) + { + dpo_reset(&buckets[ii]); + } + } + } + } + + vec_foreach (nh, nhs) + { + dpo_reset(&nh->path_dpo); + } + vec_free(nhs); + + load_balance_map_unlock(old_lbmi); +} + +static void +load_balance_lock (dpo_id_t *dpo) +{ + load_balance_t *lb; + + lb = load_balance_get(dpo->dpoi_index); + + lb->lb_locks++; +} + +static void +load_balance_destroy (load_balance_t *lb) +{ + dpo_id_t *buckets; + int i; + + buckets = load_balance_get_buckets(lb); + + for (i = 0; i < lb->lb_n_buckets; i++) + { + dpo_reset(&buckets[i]); + } + + LB_DBG(lb, "destroy"); + if (!LB_HAS_INLINE_BUCKETS(lb)) + { + vec_free(lb->lb_buckets); + } + + fib_urpf_list_unlock(lb->lb_urpf); + load_balance_map_unlock(lb->lb_map); + + pool_put(load_balance_pool, lb); +} + +static void +load_balance_unlock (dpo_id_t *dpo) +{ + load_balance_t *lb; + + lb = load_balance_get(dpo->dpoi_index); + + lb->lb_locks--; + + if (0 == lb->lb_locks) + { + load_balance_destroy(lb); + } +} + +static void +load_balance_mem_show (void) +{ + fib_show_memory_usage("load-balance", + pool_elts(load_balance_pool), + pool_len(load_balance_pool), + sizeof(load_balance_t)); + load_balance_map_show_mem(); +} + +const static dpo_vft_t lb_vft = { + .dv_lock = load_balance_lock, + .dv_unlock = load_balance_unlock, + .dv_format = format_load_balance_dpo, + .dv_mem_show = load_balance_mem_show, +}; + +/** + * @brief The per-protocol VLIB graph nodes that are assigned to a load-balance + * object. + * + * this means that these graph nodes are ones from which a load-balance is the + * parent object in the DPO-graph. + * + * We do not list all the load-balance nodes, such as the *-lookup. instead + * we are relying on the correct use of the .sibling_of field when setting + * up these sibling nodes. + */ +const static char* const load_balance_ip4_nodes[] = +{ + "ip4-load-balance", + NULL, +}; +const static char* const load_balance_ip6_nodes[] = +{ + "ip6-load-balance", + NULL, +}; +const static char* const load_balance_mpls_nodes[] = +{ + "mpls-load-balance", + NULL, +}; +const static char* const load_balance_l2_nodes[] = +{ + "l2-load-balance", + NULL, +}; +const static char* const * const load_balance_nodes[DPO_PROTO_NUM] = +{ + [DPO_PROTO_IP4] = load_balance_ip4_nodes, + [DPO_PROTO_IP6] = load_balance_ip6_nodes, + [DPO_PROTO_MPLS] = load_balance_mpls_nodes, + [DPO_PROTO_ETHERNET] = load_balance_l2_nodes, +}; + +void +load_balance_module_init (void) +{ + dpo_register(DPO_LOAD_BALANCE, &lb_vft, load_balance_nodes); + + load_balance_map_module_init(); +} + +static clib_error_t * +load_balance_show (vlib_main_t * vm, + unformat_input_t * input, + vlib_cli_command_t * cmd) +{ + index_t lbi = INDEX_INVALID; + + while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT) + { + if (unformat (input, "%d", &lbi)) + ; + else + break; + } + + if (INDEX_INVALID != lbi) + { + vlib_cli_output (vm, "%U", format_load_balance, lbi, + LOAD_BALANCE_FORMAT_DETAIL); + } + else + { + load_balance_t *lb; + + pool_foreach(lb, load_balance_pool, + ({ + vlib_cli_output (vm, "%U", format_load_balance, + load_balance_get_index(lb), + LOAD_BALANCE_FORMAT_NONE); + })); + } + + return 0; +} + +VLIB_CLI_COMMAND (load_balance_show_command, static) = { + .path = "show load-balance", + .short_help = "show load-balance [<index>]", + .function = load_balance_show, +}; + + +always_inline u32 +ip_flow_hash (void *data) +{ + ip4_header_t *iph = (ip4_header_t *) data; + + if ((iph->ip_version_and_header_length & 0xF0) == 0x40) + return ip4_compute_flow_hash (iph, IP_FLOW_HASH_DEFAULT); + else + return ip6_compute_flow_hash ((ip6_header_t *) iph, IP_FLOW_HASH_DEFAULT); +} + +always_inline u64 +mac_to_u64 (u8 * m) +{ + return (*((u64 *) m) & 0xffffffffffff); +} + +always_inline u32 +l2_flow_hash (vlib_buffer_t * b0) +{ + ethernet_header_t *eh; + u64 a, b, c; + uword is_ip, eh_size; + u16 eh_type; + + eh = vlib_buffer_get_current (b0); + eh_type = clib_net_to_host_u16 (eh->type); + eh_size = ethernet_buffer_header_size (b0); + + is_ip = (eh_type == ETHERNET_TYPE_IP4 || eh_type == ETHERNET_TYPE_IP6); + + /* since we have 2 cache lines, use them */ + if (is_ip) + a = ip_flow_hash ((u8 *) vlib_buffer_get_current (b0) + eh_size); + else + a = eh->type; + + b = mac_to_u64 ((u8 *) eh->dst_address); + c = mac_to_u64 ((u8 *) eh->src_address); + hash_mix64 (a, b, c); + + return (u32) c; +} + +typedef struct load_balance_trace_t_ +{ + index_t lb_index; +} load_balance_trace_t; + +static uword +l2_load_balance (vlib_main_t * vm, + vlib_node_runtime_t * node, + vlib_frame_t * frame) +{ + u32 n_left_from, next_index, *from, *to_next; + + from = vlib_frame_vector_args (frame); + n_left_from = frame->n_vectors; + + next_index = node->cached_next_index; + + while (n_left_from > 0) + { + u32 n_left_to_next; + + vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next); + + while (n_left_from > 0 && n_left_to_next > 0) + { + vlib_buffer_t *b0; + u32 bi0, lbi0, next0; + const dpo_id_t *dpo0; + const load_balance_t *lb0; + + bi0 = from[0]; + to_next[0] = bi0; + from += 1; + to_next += 1; + n_left_from -= 1; + n_left_to_next -= 1; + + b0 = vlib_get_buffer (vm, bi0); + + /* lookup dst + src mac */ + lbi0 = vnet_buffer (b0)->ip.adj_index[VLIB_TX]; + lb0 = load_balance_get(lbi0); + + vnet_buffer(b0)->ip.flow_hash = l2_flow_hash(b0); + + dpo0 = load_balance_get_bucket_i(lb0, + vnet_buffer(b0)->ip.flow_hash & + (lb0->lb_n_buckets_minus_1)); + + next0 = dpo0->dpoi_next_node; + vnet_buffer (b0)->ip.adj_index[VLIB_TX] = dpo0->dpoi_index; + + if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED)) + { + load_balance_trace_t *tr = vlib_add_trace (vm, node, b0, + sizeof (*tr)); + tr->lb_index = lbi0; + } + vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next, + n_left_to_next, bi0, next0); + } + + vlib_put_next_frame (vm, node, next_index, n_left_to_next); + } + + return frame->n_vectors; +} + +static u8 * +format_load_balance_trace (u8 * s, va_list * args) +{ + CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *); + CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *); + load_balance_trace_t *t = va_arg (*args, load_balance_trace_t *); + + s = format (s, "L2-load-balance: index %d", t->lb_index); + return s; +} + +/** + * @brief + */ +VLIB_REGISTER_NODE (l2_load_balance_node) = { + .function = l2_load_balance, + .name = "l2-load-balance", + .vector_size = sizeof (u32), + + .format_trace = format_load_balance_trace, + .n_next_nodes = 1, + .next_nodes = { + [0] = "error-drop", + }, +}; |