2 * Copyright (c) 2015 Cisco and/or its affiliates.
3 * Licensed under the Apache License, Version 2.0 (the "License");
4 * you may not use this file except in compliance with the License.
5 * You may obtain a copy of the License at:
7 * http://www.apache.org/licenses/LICENSE-2.0
9 * Unless required by applicable law or agreed to in writing, software
10 * distributed under the License is distributed on an "AS IS" BASIS,
11 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 * See the License for the specific language governing permissions and
13 * limitations under the License.
16 * input.c: Unix file input
18 * Copyright (c) 2008 Eliot Dresselhaus
20 * Permission is hereby granted, free of charge, to any person obtaining
21 * a copy of this software and associated documentation files (the
22 * "Software"), to deal in the Software without restriction, including
23 * without limitation the rights to use, copy, modify, merge, publish,
24 * distribute, sublicense, and/or sell copies of the Software, and to
25 * permit persons to whom the Software is furnished to do so, subject to
26 * the following conditions:
28 * The above copyright notice and this permission notice shall be
29 * included in all copies or substantial portions of the Software.
31 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
32 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
33 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
34 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
35 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
36 * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
37 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
40 #include <vlib/vlib.h>
41 #include <vlib/unix/unix.h>
45 #define HAVE_LINUX_EPOLL
47 #ifdef HAVE_LINUX_EPOLL
49 #include <sys/epoll.h>
54 struct epoll_event *epoll_events;
57 u64 epoll_files_ready;
61 static linux_epoll_main_t linux_epoll_main;
64 linux_epoll_file_update (unix_file_t * f, unix_file_update_type_t update_type)
66 unix_main_t *um = &unix_main;
67 linux_epoll_main_t *em = &linux_epoll_main;
70 memset (&e, 0, sizeof (e));
73 if (f->flags & UNIX_FILE_DATA_AVAILABLE_TO_WRITE)
75 if (f->flags & UNIX_FILE_EVENT_EDGE_TRIGGERED)
77 e.data.u32 = f - um->file_pool;
79 if (epoll_ctl (em->epoll_fd,
80 (update_type == UNIX_FILE_UPDATE_ADD
82 : (update_type == UNIX_FILE_UPDATE_MODIFY
84 : EPOLL_CTL_DEL)), f->file_descriptor, &e) < 0)
85 clib_warning ("epoll_ctl");
89 linux_epoll_input (vlib_main_t * vm,
90 vlib_node_runtime_t * node, vlib_frame_t * frame)
92 unix_main_t *um = &unix_main;
93 linux_epoll_main_t *em = &linux_epoll_main;
94 struct epoll_event *e;
98 vlib_node_main_t *nm = &vm->node_main;
99 u64 t = nm->cpu_time_next_process_ready;
101 int timeout_ms, max_timeout_ms = 10;
102 f64 vector_rate = vlib_last_vectors_per_main_loop (vm);
107 timeout_ms = max_timeout_ms;
112 (((i64) t - (i64) clib_cpu_time_now ())
113 * vm->clib_time.seconds_per_clock)
114 /* subtract off some slop time */ - 50e-6;
118 /* We have event happenning in less than 1 ms so
119 don't allow epoll to wait */
124 timeout_ms = timeout * 1e3;
126 /* Must be between 1 and 10 ms. */
127 timeout_ms = clib_max (1, timeout_ms);
128 timeout_ms = clib_min (max_timeout_ms, timeout_ms);
132 /* If we still have input nodes polling (e.g. vnet packet generator)
134 if (nm->input_node_counts_by_state[VLIB_NODE_STATE_POLLING] > 0)
138 * When busy: don't wait & only epoll for input
139 * every 1024 times through main loop.
141 if (vector_rate > 1 || vm->api_queue_nonempty)
144 node->input_main_loops_per_call = 1024;
147 /* We're not busy; go to sleep for a while. */
148 node->input_main_loops_per_call = 0;
150 /* Allow any signal to wakeup our sleep. */
152 static sigset_t unblock_all_signals;
153 n_fds_ready = epoll_pwait (em->epoll_fd,
155 vec_len (em->epoll_events),
156 timeout_ms, &unblock_all_signals);
158 /* This kludge is necessary to run over absurdly old kernels */
159 if (n_fds_ready < 0 && errno == ENOSYS)
161 n_fds_ready = epoll_wait (em->epoll_fd,
163 vec_len (em->epoll_events), timeout_ms);
170 if (unix_error_is_fatal (errno))
171 vlib_panic_with_error (vm, clib_error_return_unix (0, "epoll_wait"));
173 /* non fatal error (e.g. EINTR). */
177 em->epoll_waits += 1;
178 em->epoll_files_ready += n_fds_ready;
180 for (e = em->epoll_events; e < em->epoll_events + n_fds_ready; e++)
183 unix_file_t *f = pool_elt_at_index (um->file_pool, i);
184 clib_error_t *errors[4];
187 if (PREDICT_TRUE (!(e->events & EPOLLERR)))
189 if (e->events & EPOLLIN)
191 errors[n_errors] = f->read_function (f);
192 n_errors += errors[n_errors] != 0;
194 if (e->events & EPOLLOUT)
196 errors[n_errors] = f->write_function (f);
197 n_errors += errors[n_errors] != 0;
202 if (f->error_function)
204 errors[n_errors] = f->error_function (f);
205 n_errors += errors[n_errors] != 0;
208 close (f->file_descriptor);
211 ASSERT (n_errors < ARRAY_LEN (errors));
212 for (i = 0; i < n_errors; i++)
214 unix_save_error (um, errors[i]);
222 VLIB_REGISTER_NODE (linux_epoll_input_node,static) = {
223 .function = linux_epoll_input,
224 .type = VLIB_NODE_TYPE_PRE_INPUT,
225 .name = "unix-epoll-input",
230 linux_epoll_input_init (vlib_main_t * vm)
232 linux_epoll_main_t *em = &linux_epoll_main;
233 unix_main_t *um = &unix_main;
235 /* Allocate some events. */
236 vec_resize (em->epoll_events, VLIB_FRAME_SIZE);
238 em->epoll_fd = epoll_create (vec_len (em->epoll_events));
239 if (em->epoll_fd < 0)
240 return clib_error_return_unix (0, "epoll_create");
242 um->file_update = linux_epoll_file_update;
247 VLIB_INIT_FUNCTION (linux_epoll_input_init);
249 #endif /* HAVE_LINUX_EPOLL */
251 static clib_error_t *
252 unix_input_init (vlib_main_t * vm)
254 return vlib_call_init_function (vm, linux_epoll_input_init);
257 VLIB_INIT_FUNCTION (unix_input_init);
260 * fd.io coding-style-patch-verification: ON
263 * eval: (c-set-style "gnu")