diff options
Diffstat (limited to 'src/vnet/session/node.c')
| -rw-r--r-- | src/vnet/session/node.c | 435 |
1 files changed, 435 insertions, 0 deletions
diff --git a/src/vnet/session/node.c b/src/vnet/session/node.c new file mode 100644 index 00000000000..e467f4e99e2 --- /dev/null +++ b/src/vnet/session/node.c @@ -0,0 +1,435 @@ +/* + * Copyright (c) 2017 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 <vlib/vlib.h> +#include <vnet/vnet.h> +#include <vnet/pg/pg.h> +#include <vnet/ip/ip.h> + +#include <vnet/tcp/tcp.h> + +#include <vppinfra/hash.h> +#include <vppinfra/error.h> +#include <vppinfra/elog.h> +#include <vlibmemory/unix_shared_memory_queue.h> + +#include <vnet/udp/udp_packet.h> +#include <vnet/lisp-cp/packets.h> +#include <math.h> + +vlib_node_registration_t session_queue_node; + +typedef struct +{ + u32 session_index; + u32 server_thread_index; +} session_queue_trace_t; + +/* packet trace format function */ +static u8 * +format_session_queue_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 *); + session_queue_trace_t *t = va_arg (*args, session_queue_trace_t *); + + s = format (s, "SESSION_QUEUE: session index %d, server thread index %d", + t->session_index, t->server_thread_index); + return s; +} + +vlib_node_registration_t session_queue_node; + +#define foreach_session_queue_error \ +_(TX, "Packets transmitted") \ +_(TIMER, "Timer events") + +typedef enum +{ +#define _(sym,str) SESSION_QUEUE_ERROR_##sym, + foreach_session_queue_error +#undef _ + SESSION_QUEUE_N_ERROR, +} session_queue_error_t; + +static char *session_queue_error_strings[] = { +#define _(sym,string) string, + foreach_session_queue_error +#undef _ +}; + +static u32 session_type_to_next[] = { + SESSION_QUEUE_NEXT_TCP_IP4_OUTPUT, + SESSION_QUEUE_NEXT_IP4_LOOKUP, + SESSION_QUEUE_NEXT_TCP_IP6_OUTPUT, + SESSION_QUEUE_NEXT_IP6_LOOKUP, +}; + +always_inline int +session_fifo_rx_i (vlib_main_t * vm, vlib_node_runtime_t * node, + session_manager_main_t * smm, session_fifo_event_t * e0, + stream_session_t * s0, u32 thread_index, int *n_tx_packets, + u8 peek_data) +{ + u32 n_trace = vlib_get_trace_count (vm, node); + u32 left_to_snd0, max_len_to_snd0, len_to_deq0, n_bufs, snd_space0; + u32 n_frame_bytes, n_frames_per_evt; + transport_connection_t *tc0; + transport_proto_vft_t *transport_vft; + u32 next_index, next0, *to_next, n_left_to_next, bi0; + vlib_buffer_t *b0; + u32 rx_offset; + u16 snd_mss0; + u8 *data0; + int i; + + next_index = next0 = session_type_to_next[s0->session_type]; + + transport_vft = session_get_transport_vft (s0->session_type); + tc0 = transport_vft->get_connection (s0->connection_index, thread_index); + + /* Make sure we have space to send and there's something to dequeue */ + snd_space0 = transport_vft->send_space (tc0); + snd_mss0 = transport_vft->send_mss (tc0); + + if (snd_space0 == 0 || svm_fifo_max_dequeue (s0->server_tx_fifo) == 0 + || snd_mss0 == 0) + return 0; + + ASSERT (e0->enqueue_length > 0); + + /* Ensure we're not writing more than transport window allows */ + max_len_to_snd0 = clib_min (e0->enqueue_length, snd_space0); + + if (peek_data) + { + /* Offset in rx fifo from where to peek data */ + rx_offset = transport_vft->rx_fifo_offset (tc0); + } + + /* TODO check if transport is willing to send len_to_snd0 + * bytes (Nagle) */ + + n_frame_bytes = snd_mss0 * VLIB_FRAME_SIZE; + n_frames_per_evt = ceil ((double) max_len_to_snd0 / n_frame_bytes); + + n_bufs = vec_len (smm->tx_buffers[thread_index]); + left_to_snd0 = max_len_to_snd0; + for (i = 0; i < n_frames_per_evt; i++) + { + /* Make sure we have at least one full frame of buffers ready */ + if (PREDICT_FALSE (n_bufs < VLIB_FRAME_SIZE)) + { + vec_validate (smm->tx_buffers[thread_index], + n_bufs + VLIB_FRAME_SIZE - 1); + n_bufs += + vlib_buffer_alloc (vm, &smm->tx_buffers[thread_index][n_bufs], + VLIB_FRAME_SIZE); + + /* buffer shortage + * XXX 0.9 because when debugging we might not get a full frame */ + if (PREDICT_FALSE (n_bufs < 0.9 * VLIB_FRAME_SIZE)) + { + /* Keep track of how much we've dequeued and exit */ + e0->enqueue_length -= max_len_to_snd0 - left_to_snd0; + return -1; + } + + _vec_len (smm->tx_buffers[thread_index]) = n_bufs; + } + + vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next); + while (left_to_snd0 && n_left_to_next) + { + /* Get free buffer */ + n_bufs--; + bi0 = smm->tx_buffers[thread_index][n_bufs]; + _vec_len (smm->tx_buffers[thread_index]) = n_bufs; + + b0 = vlib_get_buffer (vm, bi0); + b0->error = 0; + b0->flags = VLIB_BUFFER_TOTAL_LENGTH_VALID + | VNET_BUFFER_LOCALLY_ORIGINATED; + b0->current_data = 0; + + /* RX on the local interface. tx in default fib */ + vnet_buffer (b0)->sw_if_index[VLIB_RX] = 0; + vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0; + + /* usual speculation, or the enqueue_x1 macro will barf */ + to_next[0] = bi0; + to_next += 1; + n_left_to_next -= 1; + + VLIB_BUFFER_TRACE_TRAJECTORY_INIT (b0); + if (PREDICT_FALSE (n_trace > 0)) + { + session_queue_trace_t *t0; + vlib_trace_buffer (vm, node, next_index, b0, + 1 /* follow_chain */ ); + vlib_set_trace_count (vm, node, --n_trace); + t0 = vlib_add_trace (vm, node, b0, sizeof (*t0)); + t0->session_index = s0->session_index; + t0->server_thread_index = s0->thread_index; + } + + if (1) + { + ELOG_TYPE_DECLARE (e) = + { + .format = "evt-dequeue: id %d length %d",.format_args = + "i4i4",}; + struct + { + u32 data[2]; + } *ed; + ed = ELOG_DATA (&vm->elog_main, e); + ed->data[0] = e0->event_id; + ed->data[1] = e0->enqueue_length; + } + + len_to_deq0 = (left_to_snd0 < snd_mss0) ? left_to_snd0 : snd_mss0; + + /* Make room for headers */ + data0 = vlib_buffer_make_headroom (b0, MAX_HDRS_LEN); + + /* Dequeue the data + * TODO 1) peek instead of dequeue + * 2) buffer chains */ + if (peek_data) + { + int n_bytes_read; + n_bytes_read = svm_fifo_peek (s0->server_tx_fifo, s0->pid, + rx_offset, len_to_deq0, data0); + if (n_bytes_read < 0) + goto dequeue_fail; + + /* Keep track of progress locally, transport is also supposed to + * increment it independently when pushing header */ + rx_offset += n_bytes_read; + } + else + { + if (svm_fifo_dequeue_nowait (s0->server_tx_fifo, s0->pid, + len_to_deq0, data0) < 0) + goto dequeue_fail; + } + + b0->current_length = len_to_deq0; + + /* Ask transport to push header */ + transport_vft->push_header (tc0, b0); + + left_to_snd0 -= len_to_deq0; + *n_tx_packets = *n_tx_packets + 1; + + 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); + } + + /* If we couldn't dequeue all bytes store progress */ + if (max_len_to_snd0 < e0->enqueue_length) + { + e0->enqueue_length -= max_len_to_snd0; + vec_add1 (smm->evts_partially_read[thread_index], *e0); + } + return 0; + +dequeue_fail: + /* Can't read from fifo. Store event rx progress, save as partially read, + * return buff to free list and return */ + e0->enqueue_length -= max_len_to_snd0 - left_to_snd0; + vec_add1 (smm->evts_partially_read[thread_index], *e0); + + to_next -= 1; + n_left_to_next += 1; + _vec_len (smm->tx_buffers[thread_index]) += 1; + + clib_warning ("dequeue fail"); + return 0; +} + +int +session_fifo_rx_peek (vlib_main_t * vm, vlib_node_runtime_t * node, + session_manager_main_t * smm, session_fifo_event_t * e0, + stream_session_t * s0, u32 thread_index, int *n_tx_pkts) +{ + return session_fifo_rx_i (vm, node, smm, e0, s0, thread_index, n_tx_pkts, + 1); +} + +int +session_fifo_rx_dequeue (vlib_main_t * vm, vlib_node_runtime_t * node, + session_manager_main_t * smm, + session_fifo_event_t * e0, stream_session_t * s0, + u32 thread_index, int *n_tx_pkts) +{ + return session_fifo_rx_i (vm, node, smm, e0, s0, thread_index, n_tx_pkts, + 0); +} + +static uword +session_queue_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node, + vlib_frame_t * frame) +{ + session_manager_main_t *smm = vnet_get_session_manager_main (); + session_fifo_event_t *my_fifo_events, *e; + u32 n_to_dequeue; + unix_shared_memory_queue_t *q; + int n_tx_packets = 0; + u32 my_thread_index = vm->cpu_index; + int i, rv; + + /* + * Update TCP time + */ + tcp_update_time (vlib_time_now (vm), my_thread_index); + + /* + * Get vpp queue events + */ + q = smm->vpp_event_queues[my_thread_index]; + if (PREDICT_FALSE (q == 0)) + return 0; + + /* min number of events we can dequeue without blocking */ + n_to_dequeue = q->cursize; + if (n_to_dequeue == 0) + return 0; + + my_fifo_events = smm->fifo_events[my_thread_index]; + + /* If we didn't manage to process previous events try going + * over them again without dequeuing new ones. + * XXX: Block senders to sessions that can't keep up */ + if (vec_len (my_fifo_events) >= 100) + goto skip_dequeue; + + /* See you in the next life, don't be late */ + if (pthread_mutex_trylock (&q->mutex)) + return 0; + + for (i = 0; i < n_to_dequeue; i++) + { + vec_add2 (my_fifo_events, e, 1); + unix_shared_memory_queue_sub_raw (q, (u8 *) e); + } + + /* The other side of the connection is not polling */ + if (q->cursize < (q->maxsize / 8)) + (void) pthread_cond_broadcast (&q->condvar); + pthread_mutex_unlock (&q->mutex); + + smm->fifo_events[my_thread_index] = my_fifo_events; + +skip_dequeue: + + for (i = 0; i < n_to_dequeue; i++) + { + svm_fifo_t *f0; /* $$$ prefetch 1 ahead maybe */ + stream_session_t *s0; + u32 server_session_index0, server_thread_index0; + session_fifo_event_t *e0; + + e0 = &my_fifo_events[i]; + f0 = e0->fifo; + server_session_index0 = f0->server_session_index; + server_thread_index0 = f0->server_thread_index; + + /* $$$ add multiple event queues, per vpp worker thread */ + ASSERT (server_thread_index0 == my_thread_index); + + s0 = pool_elt_at_index (smm->sessions[my_thread_index], + server_session_index0); + + ASSERT (s0->thread_index == my_thread_index); + + switch (e0->event_type) + { + case FIFO_EVENT_SERVER_TX: + /* Spray packets in per session type frames, since they go to + * different nodes */ + rv = (smm->session_rx_fns[s0->session_type]) (vm, node, smm, e0, s0, + my_thread_index, + &n_tx_packets); + if (rv < 0) + goto done; + + break; + + default: + clib_warning ("unhandled event type %d", e0->event_type); + } + } + +done: + + /* Couldn't process all events. Probably out of buffers */ + if (PREDICT_FALSE (i < n_to_dequeue)) + { + session_fifo_event_t *partially_read = + smm->evts_partially_read[my_thread_index]; + vec_add (partially_read, &my_fifo_events[i], n_to_dequeue - i); + vec_free (my_fifo_events); + smm->fifo_events[my_thread_index] = partially_read; + smm->evts_partially_read[my_thread_index] = 0; + } + else + { + vec_free (smm->fifo_events[my_thread_index]); + smm->fifo_events[my_thread_index] = + smm->evts_partially_read[my_thread_index]; + smm->evts_partially_read[my_thread_index] = 0; + } + + vlib_node_increment_counter (vm, session_queue_node.index, + SESSION_QUEUE_ERROR_TX, n_tx_packets); + + return n_tx_packets; +} + +/* *INDENT-OFF* */ +VLIB_REGISTER_NODE (session_queue_node) = +{ + .function = session_queue_node_fn, + .name = "session-queue", + .format_trace = format_session_queue_trace, + .type = VLIB_NODE_TYPE_INPUT, + .n_errors = ARRAY_LEN (session_queue_error_strings), + .error_strings = session_queue_error_strings, + .n_next_nodes = SESSION_QUEUE_N_NEXT, + /* .state = VLIB_NODE_STATE_DISABLED, enable on-demand? */ + /* edit / add dispositions here */ + .next_nodes = + { + [SESSION_QUEUE_NEXT_DROP] = "error-drop", + [SESSION_QUEUE_NEXT_IP4_LOOKUP] = "ip4-lookup", + [SESSION_QUEUE_NEXT_IP6_LOOKUP] = "ip6-lookup", + [SESSION_QUEUE_NEXT_TCP_IP4_OUTPUT] = "tcp4-output", + [SESSION_QUEUE_NEXT_TCP_IP6_OUTPUT] = "tcp6-output", + }, +}; +/* *INDENT-ON* */ + +/* + * fd.io coding-style-patch-verification: ON + * + * Local Variables: + * eval: (c-set-style "gnu") + * End: + */ |