1 files changed, 265 insertions, 0 deletions
diff --git a/vpp/vlib/vlib/unix/input.c b/vpp/vlib/vlib/unix/input.c
new file mode 100644
index 00000000..07096ed2
--- /dev/null
+++ b/vpp/vlib/vlib/unix/input.c
@@ -0,0 +1,265 @@
+/*
+ * Copyright (c) 2015 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.
+ */
+/*
+ * input.c: Unix file input
+ *
+ * Copyright (c) 2008 Eliot Dresselhaus
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ *  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ *  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ *  NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+ *  LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+ *  OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ *  WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+#include <vlib/vlib.h>
+#include <vlib/unix/unix.h>
+#include <signal.h>
+
+/* FIXME autoconf */
+#define HAVE_LINUX_EPOLL
+
+#ifdef HAVE_LINUX_EPOLL
+
+#include <sys/epoll.h>
+
+typedef struct
+{
+  int epoll_fd;
+  struct epoll_event *epoll_events;
+
+  /* Statistics. */
+  u64 epoll_files_ready;
+  u64 epoll_waits;
+} linux_epoll_main_t;
+
+static linux_epoll_main_t linux_epoll_main;
+
+static void
+linux_epoll_file_update (unix_file_t * f, unix_file_update_type_t update_type)
+{
+  unix_main_t *um = &unix_main;
+  linux_epoll_main_t *em = &linux_epoll_main;
+  struct epoll_event e;
+
+  memset (&e, 0, sizeof (e));
+
+  e.events = EPOLLIN;
+  if (f->flags & UNIX_FILE_DATA_AVAILABLE_TO_WRITE)
+    e.events |= EPOLLOUT;
+  if (f->flags & UNIX_FILE_EVENT_EDGE_TRIGGERED)
+    e.events |= EPOLLET;
+  e.data.u32 = f - um->file_pool;
+
+  if (epoll_ctl (em->epoll_fd,
+		 (update_type == UNIX_FILE_UPDATE_ADD
+		  ? EPOLL_CTL_ADD
+		  : (update_type == UNIX_FILE_UPDATE_MODIFY
+		     ? EPOLL_CTL_MOD
+		     : EPOLL_CTL_DEL)), f->file_descriptor, &e) < 0)
+    clib_warning ("epoll_ctl");
+}
+
+static uword
+linux_epoll_input (vlib_main_t * vm,
+		   vlib_node_runtime_t * node, vlib_frame_t * frame)
+{
+  unix_main_t *um = &unix_main;
+  linux_epoll_main_t *em = &linux_epoll_main;
+  struct epoll_event *e;
+  int n_fds_ready;
+
+  {
+    vlib_node_main_t *nm = &vm->node_main;
+    u64 t = nm->cpu_time_next_process_ready;
+    f64 timeout;
+    int timeout_ms, max_timeout_ms = 10;
+    f64 vector_rate = vlib_last_vectors_per_main_loop (vm);
+
+    if (t == ~0ULL)
+      {
+	timeout = 10e-3;
+	timeout_ms = max_timeout_ms;
+      }
+    else
+      {
+	timeout =
+	  (((i64) t - (i64) clib_cpu_time_now ())
+	   * vm->clib_time.seconds_per_clock)
+	  /* subtract off some slop time */  - 50e-6;
+
+	if (timeout < 1e3)
+	  {
+	    /* We have event happenning in less than 1 ms so
+	       don't allow epoll to wait */
+	    timeout_ms = 0;
+	  }
+	else
+	  {
+	    timeout_ms = timeout * 1e3;
+
+	    /* Must be between 1 and 10 ms. */
+	    timeout_ms = clib_max (1, timeout_ms);
+	    timeout_ms = clib_min (max_timeout_ms, timeout_ms);
+	  }
+      }
+
+    /* If we still have input nodes polling (e.g. vnet packet generator)
+       don't sleep. */
+    if (nm->input_node_counts_by_state[VLIB_NODE_STATE_POLLING] > 0)
+      timeout_ms = 0;
+
+    /*
+     * When busy: don't wait & only epoll for input
+     * every 1024 times through main loop.
+     */
+    if (vector_rate > 1 || vm->api_queue_nonempty)
+      {
+	timeout_ms = 0;
+	node->input_main_loops_per_call = 1024;
+      }
+    else
+      /* We're not busy; go to sleep for a while. */
+      node->input_main_loops_per_call = 0;
+
+    /* Allow any signal to wakeup our sleep. */
+    {
+      static sigset_t unblock_all_signals;
+      n_fds_ready = epoll_pwait (em->epoll_fd,
+				 em->epoll_events,
+				 vec_len (em->epoll_events),
+				 timeout_ms, &unblock_all_signals);
+
+      /* This kludge is necessary to run over absurdly old kernels */
+      if (n_fds_ready < 0 && errno == ENOSYS)
+	{
+	  n_fds_ready = epoll_wait (em->epoll_fd,
+				    em->epoll_events,
+				    vec_len (em->epoll_events), timeout_ms);
+	}
+    }
+  }
+
+  if (n_fds_ready < 0)
+    {
+      if (unix_error_is_fatal (errno))
+	vlib_panic_with_error (vm, clib_error_return_unix (0, "epoll_wait"));
+
+      /* non fatal error (e.g. EINTR). */
+      return 0;
+    }
+
+  em->epoll_waits += 1;
+  em->epoll_files_ready += n_fds_ready;
+
+  for (e = em->epoll_events; e < em->epoll_events + n_fds_ready; e++)
+    {
+      u32 i = e->data.u32;
+      unix_file_t *f = pool_elt_at_index (um->file_pool, i);
+      clib_error_t *errors[4];
+      int n_errors = 0;
+
+      if (PREDICT_TRUE (!(e->events & EPOLLERR)))
+	{
+	  if (e->events & EPOLLIN)
+	    {
+	      errors[n_errors] = f->read_function (f);
+	      n_errors += errors[n_errors] != 0;
+	    }
+	  if (e->events & EPOLLOUT)
+	    {
+	      errors[n_errors] = f->write_function (f);
+	      n_errors += errors[n_errors] != 0;
+	    }
+	}
+      else
+	{
+	  if (f->error_function)
+	    {
+	      errors[n_errors] = f->error_function (f);
+	      n_errors += errors[n_errors] != 0;
+	    }
+	  else
+	    close (f->file_descriptor);
+	}
+
+      ASSERT (n_errors < ARRAY_LEN (errors));
+      for (i = 0; i < n_errors; i++)
+	{
+	  unix_save_error (um, errors[i]);
+	}
+    }
+
+  return 0;
+}
+
+/* *INDENT-OFF* */
+VLIB_REGISTER_NODE (linux_epoll_input_node,static) = {
+  .function = linux_epoll_input,
+  .type = VLIB_NODE_TYPE_PRE_INPUT,
+  .name = "unix-epoll-input",
+};
+/* *INDENT-ON* */
+
+clib_error_t *
+linux_epoll_input_init (vlib_main_t * vm)
+{
+  linux_epoll_main_t *em = &linux_epoll_main;
+  unix_main_t *um = &unix_main;
+
+  /* Allocate some events. */
+  vec_resize (em->epoll_events, VLIB_FRAME_SIZE);
+
+  em->epoll_fd = epoll_create (vec_len (em->epoll_events));
+  if (em->epoll_fd < 0)
+    return clib_error_return_unix (0, "epoll_create");
+
+  um->file_update = linux_epoll_file_update;
+
+  return 0;
+}
+
+VLIB_INIT_FUNCTION (linux_epoll_input_init);
+
+#endif /* HAVE_LINUX_EPOLL */
+
+static clib_error_t *
+unix_input_init (vlib_main_t * vm)
+{
+  return vlib_call_init_function (vm, linux_epoll_input_init);
+}
+
+VLIB_INIT_FUNCTION (unix_input_init);
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */