interface: rx queue infra rework, part one

Type: improvement
Change-Id: I4008cadfd5141f921afbdc09a3ebcd1dcf88eb29
Signed-off-by: Damjan Marion <damarion@cisco.com>

1 files changed, 229 insertions, 0 deletions

diff --git a/src/vnet/interface/runtime.c b/src/vnet/interface/runtime.c
new file mode 100644
index 00000000000..c1b096f3c86
--- /dev/null
+++ b/src/vnet/interface/runtime.c
@@ -0,0 +1,229 @@
+/*
+ * Copyright (c) 2020 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/vnet.h>
+#include <vnet/devices/devices.h>
+#include <vnet/feature/feature.h>
+#include <vnet/ip/ip.h>
+#include <vnet/ethernet/ethernet.h>
+#include <vnet/interface/rx_queue_funcs.h>
+#include <vlib/unix/unix.h>
+
+VLIB_REGISTER_LOG_CLASS (if_rxq_log, static) = {
+  .class_name = "interface",
+  .subclass_name = "runtime",
+};
+
+#define log_debug(fmt, ...) vlib_log_debug (if_rxq_log.class, fmt, __VA_ARGS__)
+#define log_err(fmt, ...)   vlib_log_err (if_rxq_log.class, fmt, __VA_ARGS__)
+
+static char *node_state_str[] = {
+  [VLIB_NODE_STATE_DISABLED] = "disabled",
+  [VLIB_NODE_STATE_POLLING] = "polling",
+  [VLIB_NODE_STATE_INTERRUPT] = "interrupt",
+};
+
+static int
+poll_data_sort (void *a1, void *a2)
+{
+  vnet_hw_if_rxq_poll_vector_t *pv1 = a1;
+  vnet_hw_if_rxq_poll_vector_t *pv2 = a2;
+
+  if (pv1->dev_instance > pv2->dev_instance)
+    return 1;
+  else if (pv1->dev_instance < pv2->dev_instance)
+    return -1;
+  else if (pv1->queue_id > pv2->queue_id)
+    return 1;
+  else if (pv1->queue_id < pv2->queue_id)
+    return -1;
+  else
+    return 0;
+}
+
+void
+vnet_hw_if_update_runtime_data (vnet_main_t *vnm, u32 hw_if_index)
+{
+  vlib_main_t *vm = vlib_get_main ();
+  vnet_interface_main_t *im = &vnm->interface_main;
+  vnet_hw_interface_t *hi = vnet_get_hw_interface (vnm, hw_if_index);
+  u32 node_index = hi->input_node_index;
+  vnet_hw_if_rx_queue_t *rxq;
+  vnet_hw_if_rxq_poll_vector_t *pv, **d = 0;
+  vlib_node_state_t *per_thread_node_state = 0;
+  u32 n_threads = vec_len (vlib_mains);
+  int something_changed = 0;
+  clib_bitmap_t *pending_int = 0;
+  int last_int = -1;
+
+  log_debug ("update node '%U' triggered by interface %v",
+	     format_vlib_node_name, vm, node_index, hi->name);
+
+  vec_validate (d, n_threads - 1);
+  vec_validate_init_empty (per_thread_node_state, n_threads - 1,
+			   VLIB_NODE_STATE_DISABLED);
+
+  /* find out desired node state on each thread */
+  pool_foreach (rxq, im->hw_if_rx_queues)
+    {
+      u32 ti = rxq->thread_index;
+
+      ASSERT (rxq->mode != VNET_HW_IF_RX_MODE_UNKNOWN);
+      ASSERT (rxq->mode != VNET_HW_IF_RX_MODE_DEFAULT);
+
+      hi = vnet_get_hw_interface (vnm, rxq->hw_if_index);
+
+      if (hi->input_node_index != node_index)
+	continue;
+
+      if (rxq->mode == VNET_HW_IF_RX_MODE_POLLING)
+	per_thread_node_state[ti] = VLIB_NODE_STATE_POLLING;
+
+      if (per_thread_node_state[ti] == VLIB_NODE_STATE_POLLING)
+	continue;
+
+      if (rxq->mode == VNET_HW_IF_RX_MODE_INTERRUPT ||
+	  rxq->mode == VNET_HW_IF_RX_MODE_ADAPTIVE)
+	per_thread_node_state[ti] = VLIB_NODE_STATE_INTERRUPT;
+    }
+
+  /* construct per-thread polling vectors */
+  pool_foreach (rxq, im->hw_if_rx_queues)
+    {
+      u32 ti = rxq->thread_index;
+      uword flags;
+
+      hi = vnet_get_hw_interface (vnm, rxq->hw_if_index);
+
+      if (hi->input_node_index != node_index)
+	continue;
+
+      flags = vnet_sw_interface_get_flags (vnm, hi->sw_if_index);
+      if ((flags & VNET_SW_INTERFACE_FLAG_ADMIN_UP) == 0)
+	{
+	  log_debug ("skip interface %v (admin down)", hi->name);
+	  continue;
+	}
+
+      if (rxq->mode == VNET_HW_IF_RX_MODE_INTERRUPT ||
+	  rxq->mode == VNET_HW_IF_RX_MODE_ADAPTIVE)
+	last_int = clib_max (last_int, rxq - im->hw_if_rx_queues);
+
+      if (per_thread_node_state[ti] != VLIB_NODE_STATE_POLLING)
+	continue;
+
+      vec_add2_aligned (d[ti], pv, 1, CLIB_CACHE_LINE_BYTES);
+      pv->dev_instance = rxq->dev_instance;
+      pv->queue_id = rxq->queue_id;
+    }
+
+  /* sort poll vectors and compare them with active ones to avoid
+   * unnecesary barrier */
+  for (int i = 0; i < n_threads; i++)
+    {
+      vlib_node_state_t old_state;
+      vec_sort_with_function (d[i], poll_data_sort);
+
+      old_state = vlib_node_get_state (vlib_mains[i], node_index);
+      if (per_thread_node_state[i] != old_state)
+	{
+	  something_changed = 1;
+	  log_debug ("state changed for node %U on thread %u from %s to %s",
+		     format_vlib_node_name, vm, node_index, i,
+		     node_state_str[old_state],
+		     node_state_str[per_thread_node_state[i]]);
+	}
+
+      /* check if something changed */
+      if (something_changed == 0)
+	{
+	  vnet_hw_if_rx_node_runtime_t *rt;
+	  rt = vlib_node_get_runtime_data (vlib_mains[i], node_index);
+	  if (vec_len (rt->rxq_poll_vector) != vec_len (d[i]))
+	    something_changed = 1;
+	  else if (memcmp (d[i], rt->rxq_poll_vector,
+			   vec_len (d[i]) * sizeof (*d)))
+	    something_changed = 1;
+	  if (clib_interrupt_get_n_int (rt->rxq_interrupts) != last_int + 1)
+	    something_changed = 1;
+	}
+    }
+
+  if (something_changed)
+    {
+      int with_barrier;
+
+      if (vlib_worker_thread_barrier_held ())
+	{
+	  with_barrier = 0;
+	  log_debug ("%s", "already running under the barrier");
+	}
+      else
+	with_barrier = 1;
+
+      if (with_barrier)
+	vlib_worker_thread_barrier_sync (vm);
+
+      for (int i = 0; i < n_threads; i++)
+	{
+	  vlib_main_t *vm = vlib_mains[i];
+	  vnet_hw_if_rx_node_runtime_t *rt;
+	  rt = vlib_node_get_runtime_data (vm, node_index);
+	  pv = rt->rxq_poll_vector;
+	  rt->rxq_poll_vector = d[i];
+	  d[i] = pv;
+
+	  if (rt->rxq_interrupts)
+	    {
+	      void *in = rt->rxq_interrupts;
+	      int int_num = -1;
+	      while ((int_num = clib_interrupt_get_next (in, int_num)) != -1)
+		{
+		  clib_interrupt_clear (in, int_num);
+		  pending_int = clib_bitmap_set (pending_int, int_num, 1);
+		}
+	    }
+
+	  vlib_node_set_state (vm, node_index, per_thread_node_state[i]);
+
+	  if (last_int >= 0)
+	    clib_interrupt_resize (&rt->rxq_interrupts, last_int + 1);
+	  else
+	    clib_interrupt_free (&rt->rxq_interrupts);
+	}
+
+      if (with_barrier)
+	vlib_worker_thread_barrier_release (vm);
+    }
+  else
+    log_debug ("skipping update of node '%U', no changes detected",
+	       format_vlib_node_name, vm, node_index);
+
+  if (pending_int)
+    {
+      int i;
+      clib_bitmap_foreach (i, pending_int)
+	{
+	  vnet_hw_if_rx_queue_set_int_pending (vnm, i);
+	}
+      clib_bitmap_free (pending_int);
+    }
+
+  for (int i = 0; i < n_threads; i++)
+    vec_free (d[i]);
+
+  vec_free (d);
+  vec_free (per_thread_node_state);
+}