buffers: configurable buffer fault injector

[vpp.git] / src / vlib / main.c

diff --git a/src/vlib/main.c b/src/vlib/main.c
index 94218d3..fb3eb10 100644 (file)
--- a/src/vlib/main.c
+++ b/src/vlib/main.c
@@ -190,6 +190,31 @@ vlib_get_frame_to_node (vlib_main_t * vm, u32 to_node_index)
   return vlib_get_frame (vm, f);
 }
 
+static inline void
+vlib_validate_frame_indices (vlib_frame_t * f)
+{
+  if (CLIB_DEBUG > 0)
+    {
+      int i;
+      u32 *from = vlib_frame_vector_args (f);
+
+      /* Check for bad buffer index values */
+      for (i = 0; i < f->n_vectors; i++)
+       {
+         if (from[i] == 0)
+           {
+             clib_warning ("BUG: buffer index 0 at index %d", i);
+             ASSERT (0);
+           }
+         else if (from[i] == 0xfefefefe)
+           {
+             clib_warning ("BUG: frame poison pattern at index %d", i);
+             ASSERT (0);
+           }
+       }
+    }
+}
+
 void
 vlib_put_frame_to_node (vlib_main_t * vm, u32 to_node_index, vlib_frame_t * f)
 {
@@ -199,6 +224,8 @@ vlib_put_frame_to_node (vlib_main_t * vm, u32 to_node_index, vlib_frame_t * f)
   if (f->n_vectors == 0)
     return;
 
+  vlib_validate_frame_indices (f);
+
   to_node = vlib_get_node (vm, to_node_index);
 
   vec_add2 (vm->node_main.pending_frames, p, 1);
@@ -432,6 +459,9 @@ vlib_put_next_frame_validate (vlib_main_t * vm,
   f = vlib_get_frame (vm, nf->frame);
 
   ASSERT (n_vectors_left <= VLIB_FRAME_SIZE);
+
+  vlib_validate_frame_indices (f);
+
   n_after = VLIB_FRAME_SIZE - n_vectors_left;
   n_before = f->n_vectors;
 
@@ -1683,6 +1713,7 @@ vlib_main_or_worker_loop (vlib_main_t * vm, int is_main)
   vlib_thread_main_t *tm = vlib_get_thread_main ();
   uword i;
   u64 cpu_time_now;
+  f64 now;
   vlib_frame_queue_main_t *fqm;
   u32 *last_node_runtime_indices = 0;
   u32 frame_queue_check_counter = 0;
@@ -1926,6 +1957,33 @@ vlib_main_or_worker_loop (vlib_main_t * vm, int is_main)
       /* Record time stamp in case there are no enabled nodes and above
          calls do not update time stamp. */
       cpu_time_now = clib_cpu_time_now ();
+      vm->loops_this_reporting_interval++;
+      now = clib_time_now_internal (&vm->clib_time, cpu_time_now);
+      /* Time to update loops_per_second? */
+      if (PREDICT_FALSE (now >= vm->loop_interval_end))
+       {
+         /* Next sample ends in 20ms */
+         if (vm->loop_interval_start)
+           {
+             f64 this_loops_per_second;
+
+             this_loops_per_second =
+               ((f64) vm->loops_this_reporting_interval) / (now -
+                                                            vm->loop_interval_start);
+
+             vm->loops_per_second =
+               vm->loops_per_second * vm->damping_constant +
+               (1.0 - vm->damping_constant) * this_loops_per_second;
+             if (vm->loops_per_second != 0.0)
+               vm->seconds_per_loop = 1.0 / vm->loops_per_second;
+             else
+               vm->seconds_per_loop = 0.0;
+           }
+         /* New interval starts now, and ends in 20ms */
+         vm->loop_interval_start = now;
+         vm->loop_interval_end = now + 2e-4;
+         vm->loops_this_reporting_interval = 0;
+       }
     }
 }
 
@@ -1958,6 +2016,20 @@ vlib_main_configure (vlib_main_t * vm, unformat_input_t * input)
        ;
       else if (unformat (input, "elog-post-mortem-dump"))
        vm->elog_post_mortem_dump = 1;
+      else if (unformat (input, "buffer-alloc-success-rate %f",
+                        &vm->buffer_alloc_success_rate))
+       {
+         if (VLIB_BUFFER_ALLOC_FAULT_INJECTOR == 0)
+           return clib_error_return
+             (0, "Buffer fault injection not configured");
+       }
+      else if (unformat (input, "buffer-alloc-success-seed %u",
+                        &vm->buffer_alloc_success_seed))
+       {
+         if (VLIB_BUFFER_ALLOC_FAULT_INJECTOR == 0)
+           return clib_error_return
+             (0, "Buffer fault injection not configured");
+       }
       else
        return unformat_parse_error (input);
     }
@@ -2119,9 +2191,26 @@ vlib_main (vlib_main_t * volatile vm, unformat_input_t * input)
   vec_validate (vm->processing_rpc_requests, 0);
   _vec_len (vm->processing_rpc_requests) = 0;
 
+  /* Default params for the buffer allocator fault injector, if configured */
+  if (VLIB_BUFFER_ALLOC_FAULT_INJECTOR > 0)
+    {
+      vm->buffer_alloc_success_seed = 0xdeaddabe;
+      vm->buffer_alloc_success_rate = 0.80;
+    }
+
   if ((error = vlib_call_all_config_functions (vm, input, 0 /* is_early */ )))
     goto done;
 
+  /*
+   * Use exponential smoothing, with a half-life of 1 second
+   * reported_rate(t) = reported_rate(t-1) * K + rate(t)*(1-K)
+   *
+   * Sample every 20ms, aka 50 samples per second
+   * K = exp (-1.0/20.0);
+   * K = 0.95
+   */
+  vm->damping_constant = exp (-1.0 / 20.0);
+
   /* Sort per-thread init functions before we start threads */
   vlib_sort_init_exit_functions (&vm->worker_init_function_registrations);