/* * nsim.c - skeleton vpp engine plug-in * * Copyright (c) * 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 #include #include #include #include typedef struct { f64 expired; u32 tx_sw_if_index; } nsim_tx_trace_t; #ifndef CLIB_MARCH_VARIANT /* packet trace format function */ static u8 * format_nsim_tx_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 *); nsim_tx_trace_t *t = va_arg (*args, nsim_tx_trace_t *); s = format (s, "NSIM: tx at %.6f sw_if_index %d", t->expired, t->tx_sw_if_index); return s; } #endif /* CLIB_MARCH_VARIANT */ #define foreach_nsim_tx_error \ _(TX, "Packets transmitted") \ _(DROPPED, "No buffer drops") typedef enum { #define _(sym,str) NSIM_TX_ERROR_##sym, foreach_nsim_tx_error #undef _ NSIM_N_ERROR, } nsim_tx_error_t; #ifndef CLIB_MARCH_VARIANT static char *nsim_tx_error_strings[] = { #define _(sym,string) string, foreach_nsim_tx_error #undef _ }; #endif /* CLIB_MARCH_VARIANT */ typedef enum { NSIM_NEXT_DROP, NSIM_N_NEXT, } nsim_next_t; always_inline uword nsim_input_inline (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * f, int is_trace) { nsim_main_t *nsm = &nsim_main; u32 my_thread_index = vm->thread_index; u32 *my_buffer_cache = nsm->buffer_indices_by_thread[my_thread_index]; nsim_wheel_t *wp = nsm->wheel_by_thread[my_thread_index]; u32 n_trace = vlib_get_trace_count (vm, node); f64 now = vlib_time_now (vm); uword n_rx_packets = 0; vlib_buffer_t *b0; u32 bi0, next0; vlib_buffer_free_list_t *fl; u32 *to_next; u32 next_index; u32 n_left_to_next; nsim_wheel_entry_t *ep; /* Nothing on the scheduler wheel? */ if (wp->cursize == 0) return 0; /* First entry on the wheel isn't expired? */ ep = wp->entries + wp->head; if (ep->tx_time > now) return n_rx_packets; /* * We use per-thread buffer caches, so we need the freelist to * initialize them... */ fl = vlib_buffer_get_free_list (vm, VLIB_BUFFER_DEFAULT_FREE_LIST_INDEX); next_index = node->cached_next_index; while (wp->cursize) { /* Be aware: this is not the usual coding pattern */ vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next); while (n_left_to_next > 0 && ep->tx_time <= now) { /* Out of local buffer cache? */ if (PREDICT_FALSE (_vec_len (my_buffer_cache) == 0)) { u32 n = vlib_buffer_alloc (vm, my_buffer_cache, VLIB_FRAME_SIZE); _vec_len (my_buffer_cache) = n; /* Ugh, drop the rest of the expired entries */ if (n == 0) { u32 drops = 0; while (ep->tx_time <= now && wp->cursize) { wp->head++; if (wp->head == wp->wheel_size) wp->head = 0; ep = wp->entries + wp->head; wp->cursize--; drops++; } /* Count the drops */ vlib_node_increment_counter (vm, node->node_index, NSIM_TX_ERROR_DROPPED, drops); /* Ship any pkts we already processed */ vlib_put_next_frame (vm, node, next_index, n_left_to_next); return n_rx_packets + drops; } } /* Allocate a buffer */ bi0 = my_buffer_cache[_vec_len (my_buffer_cache) - 1]; _vec_len (my_buffer_cache) -= 1; to_next[0] = bi0; to_next += 1; n_left_to_next -= 1; b0 = vlib_get_buffer (vm, bi0); /* Initialize the buffer */ vlib_buffer_init_for_free_list (b0, fl); b0->current_data = 0; b0->current_length = ep->current_length; VLIB_BUFFER_TRACE_TRAJECTORY_INIT (b0); if (PREDICT_FALSE (n_trace)) { nsim_tx_trace_t *t0; vlib_trace_buffer (vm, node, next_index, b0, 0 /* follow_chain */ ); t0 = vlib_add_trace (vm, node, b0, sizeof (*t0)); t0->expired = ep->tx_time; t0->tx_sw_if_index = ep->tx_sw_if_index; } /* Copy data from the ring */ clib_memcpy_fast (b0->data, ep->data, ep->current_length); b0->flags |= VLIB_BUFFER_TOTAL_LENGTH_VALID; vnet_buffer (b0)->sw_if_index[VLIB_TX] = ep->tx_sw_if_index; vnet_buffer (b0)->sw_if_index[VLIB_RX] = (ep->tx_sw_if_index == nsm->sw_if_index0) ? nsm->sw_if_index1 : nsm->sw_if_index0; next0 = (ep->tx_sw_if_index == nsm->sw_if_index0) ? nsm->output_next_index0 : nsm->output_next_index1; /* verify speculative enqueue, maybe switch current next frame */ vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next, n_left_to_next, bi0, next0); /* Advance to the next ring entry */ wp->head++; if (wp->head == wp->wheel_size) wp->head = 0; wp->cursize--; ep = wp->entries + wp->head; n_rx_packets++; /* Out of ring entries? */ if (PREDICT_FALSE (wp->cursize == 0)) break; } vlib_put_next_frame (vm, node, next_index, n_left_to_next); /* If the current entry hasn't expired, we're done */ if (ep->tx_time > now) break; } return n_rx_packets; } VLIB_NODE_FN (nsim_input_node) (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame) { if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE)) return nsim_input_inline (vm, node, frame, 1 /* is_trace */ ); else return nsim_input_inline (vm, node, frame, 0 /* is_trace */ ); } /* *INDENT-OFF* */ #ifndef CLIB_MARCH_VARIANT VLIB_REGISTER_NODE (nsim_input_node) = { .type = VLIB_NODE_TYPE_INPUT, .name = "nsim-wheel", /* Will be enabled if/when the feature is configured */ .state = VLIB_NODE_STATE_DISABLED, .format_trace = format_nsim_tx_trace, .n_errors = NSIM_N_ERROR, .error_strings = nsim_tx_error_strings, }; #endif /* CLIB_MARCH_VARIANT */ /* *INDENT-ON* */ /* * fd.io coding-style-patch-verification: ON * * Local Variables: * eval: (c-set-style "gnu") * End: */