summaryrefslogtreecommitdiffstats
path: root/src/plugins/nsim/nsim_input.c
diff options
context:
space:
mode:
authorDave Barach <dave@barachs.net>2018-09-21 13:10:28 -0400
committerDamjan Marion <dmarion@me.com>2018-09-24 08:08:34 +0000
commit9e3252b5cec76dddb9877e593c799ebe15cae0af (patch)
tree37a848d9e9bb0ff59f8b54e5bab9380df39a4ebc /src/plugins/nsim/nsim_input.c
parentbdc0e6b7204ea0211d4f7881497e4306586fb9ef (diff)
Network delay simulator plugin
Change-Id: I4a70c7df8f0cb368a4e1cb16f30eeef5c6058c79 Signed-off-by: Dave Barach <dave@barachs.net>
Diffstat (limited to 'src/plugins/nsim/nsim_input.c')
-rw-r--r--src/plugins/nsim/nsim_input.c228
1 files changed, 228 insertions, 0 deletions
diff --git a/src/plugins/nsim/nsim_input.c b/src/plugins/nsim/nsim_input.c
new file mode 100644
index 00000000000..50dbcb97d6b
--- /dev/null
+++ b/src/plugins/nsim/nsim_input.c
@@ -0,0 +1,228 @@
+/*
+ * nsim.c - skeleton vpp engine plug-in
+ *
+ * Copyright (c) <current-year> <your-organization>
+ * 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 <vppinfra/error.h>
+#include <nsim/nsim.h>
+
+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 */
+
+vlib_node_registration_t nsim_node;
+
+#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];
+ 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;
+
+ /* Copy data from the ring */
+ clib_memcpy (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:
+ */