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>
44 #include <vppinfra/tw_timer_1t_3w_1024sl_ov.h>
47 #define HAVE_LINUX_EPOLL
49 #ifdef HAVE_LINUX_EPOLL
51 #include <sys/epoll.h>
56 struct epoll_event *epoll_events;
60 u64 epoll_files_ready;
64 static linux_epoll_main_t *linux_epoll_mains = 0;
67 linux_epoll_file_update (clib_file_t * f, clib_file_update_type_t update_type)
69 clib_file_main_t *fm = &file_main;
70 linux_epoll_main_t *em = vec_elt_at_index (linux_epoll_mains,
71 f->polling_thread_index);
72 struct epoll_event e = { 0 };
76 if (f->flags & UNIX_FILE_DATA_AVAILABLE_TO_WRITE)
78 if (f->flags & UNIX_FILE_EVENT_EDGE_TRIGGERED)
80 e.data.u32 = f - fm->file_pool;
86 case UNIX_FILE_UPDATE_ADD:
91 case UNIX_FILE_UPDATE_MODIFY:
95 case UNIX_FILE_UPDATE_DELETE:
101 clib_warning ("unknown update_type %d", update_type);
105 /* worker threads open epoll fd only if needed */
106 if (update_type == UNIX_FILE_UPDATE_ADD && em->epoll_fd == -1)
108 em->epoll_fd = epoll_create (1);
109 if (em->epoll_fd < 0)
111 clib_unix_warning ("epoll_create");
117 if (epoll_ctl (em->epoll_fd, op, f->file_descriptor, &e) < 0)
119 clib_unix_warning ("epoll_ctl");
123 em->n_epoll_fds += add_del;
125 if (em->n_epoll_fds == 0)
127 close (em->epoll_fd);
132 static_always_inline uword
133 linux_epoll_input_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
134 vlib_frame_t * frame, u32 thread_index)
136 unix_main_t *um = &unix_main;
137 clib_file_main_t *fm = &file_main;
138 linux_epoll_main_t *em = vec_elt_at_index (linux_epoll_mains, thread_index);
139 struct epoll_event *e;
141 int is_main = (thread_index == 0);
144 vlib_node_main_t *nm = &vm->node_main;
145 u32 ticks_until_expiration;
147 int timeout_ms = 0, max_timeout_ms = 10;
148 f64 vector_rate = vlib_last_vectors_per_main_loop (vm);
150 /* If we're not working very hard, decide how long to sleep */
151 if (is_main && vector_rate < 2 && vm->api_queue_nonempty == 0
152 && nm->input_node_counts_by_state[VLIB_NODE_STATE_POLLING] == 0)
154 ticks_until_expiration = TW (tw_timer_first_expires_in_ticks)
155 ((TWT (tw_timer_wheel) *) nm->timing_wheel);
157 /* Nothing on the fast wheel, sleep 10ms */
158 if (ticks_until_expiration == TW_SLOTS_PER_RING)
161 timeout_ms = max_timeout_ms;
165 timeout = (f64) ticks_until_expiration *1e-5;
170 timeout_ms = timeout * 1e3;
171 /* Must be between 1 and 10 ms. */
172 timeout_ms = clib_max (1, timeout_ms);
173 timeout_ms = clib_min (max_timeout_ms, timeout_ms);
176 node->input_main_loops_per_call = 0;
178 else if (is_main == 0 && vector_rate < 2 &&
179 nm->input_node_counts_by_state[VLIB_NODE_STATE_POLLING] == 0)
182 timeout_ms = max_timeout_ms;
183 node->input_main_loops_per_call = 0;
187 /* Don't come back for a respectable number of dispatch cycles */
188 node->input_main_loops_per_call = 1024;
191 /* Allow any signal to wakeup our sleep. */
192 if (is_main || em->epoll_fd != -1)
194 static sigset_t unblock_all_signals;
195 n_fds_ready = epoll_pwait (em->epoll_fd,
197 vec_len (em->epoll_events),
198 timeout_ms, &unblock_all_signals);
200 /* This kludge is necessary to run over absurdly old kernels */
201 if (n_fds_ready < 0 && errno == ENOSYS)
203 n_fds_ready = epoll_wait (em->epoll_fd,
205 vec_len (em->epoll_events), timeout_ms);
211 usleep (timeout_ms * 1000);
218 if (unix_error_is_fatal (errno))
219 vlib_panic_with_error (vm, clib_error_return_unix (0, "epoll_wait"));
221 /* non fatal error (e.g. EINTR). */
225 em->epoll_waits += 1;
226 em->epoll_files_ready += n_fds_ready;
228 for (e = em->epoll_events; e < em->epoll_events + n_fds_ready; e++)
231 clib_file_t *f = pool_elt_at_index (fm->file_pool, i);
232 clib_error_t *errors[4];
235 if (PREDICT_TRUE (!(e->events & EPOLLERR)))
237 if (e->events & EPOLLIN)
239 errors[n_errors] = f->read_function (f);
241 n_errors += errors[n_errors] != 0;
243 if (e->events & EPOLLOUT)
245 errors[n_errors] = f->write_function (f);
247 n_errors += errors[n_errors] != 0;
252 if (f->error_function)
254 errors[n_errors] = f->error_function (f);
256 n_errors += errors[n_errors] != 0;
259 close (f->file_descriptor);
262 ASSERT (n_errors < ARRAY_LEN (errors));
263 for (i = 0; i < n_errors; i++)
265 unix_save_error (um, errors[i]);
273 linux_epoll_input (vlib_main_t * vm,
274 vlib_node_runtime_t * node, vlib_frame_t * frame)
276 u32 thread_index = vlib_get_thread_index ();
278 if (thread_index == 0)
279 return linux_epoll_input_inline (vm, node, frame, 0);
281 return linux_epoll_input_inline (vm, node, frame, thread_index);
285 VLIB_REGISTER_NODE (linux_epoll_input_node,static) = {
286 .function = linux_epoll_input,
287 .type = VLIB_NODE_TYPE_PRE_INPUT,
288 .name = "unix-epoll-input",
293 linux_epoll_input_init (vlib_main_t * vm)
295 linux_epoll_main_t *em;
296 clib_file_main_t *fm = &file_main;
297 vlib_thread_main_t *tm = vlib_get_thread_main ();
300 vec_validate_aligned (linux_epoll_mains, tm->n_vlib_mains,
301 CLIB_CACHE_LINE_BYTES);
303 vec_foreach (em, linux_epoll_mains)
305 /* Allocate some events. */
306 vec_resize (em->epoll_events, VLIB_FRAME_SIZE);
308 if (linux_epoll_mains == em)
310 em->epoll_fd = epoll_create (1);
311 if (em->epoll_fd < 0)
312 return clib_error_return_unix (0, "epoll_create");
318 fm->file_update = linux_epoll_file_update;
323 VLIB_INIT_FUNCTION (linux_epoll_input_init);
325 #endif /* HAVE_LINUX_EPOLL */
327 static clib_error_t *
328 unix_input_init (vlib_main_t * vm)
330 return vlib_call_init_function (vm, linux_epoll_input_init);
333 VLIB_INIT_FUNCTION (unix_input_init);
336 * fd.io coding-style-patch-verification: ON
339 * eval: (c-set-style "gnu")