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;
71 memset (&e, 0, sizeof (e));
74 if (f->flags & UNIX_FILE_DATA_AVAILABLE_TO_WRITE)
76 if (f->flags & UNIX_FILE_EVENT_EDGE_TRIGGERED)
78 e.data.u32 = f - um->file_pool;
84 case UNIX_FILE_UPDATE_ADD:
88 case UNIX_FILE_UPDATE_MODIFY:
92 case UNIX_FILE_UPDATE_DELETE:
97 clib_warning ("unknown update_type %d", update_type);
101 if (epoll_ctl (em->epoll_fd, op, f->file_descriptor, &e) < 0)
102 clib_unix_warning ("epoll_ctl");
106 linux_epoll_input (vlib_main_t * vm,
107 vlib_node_runtime_t * node, vlib_frame_t * frame)
109 unix_main_t *um = &unix_main;
110 linux_epoll_main_t *em = &linux_epoll_main;
111 struct epoll_event *e;
115 vlib_node_main_t *nm = &vm->node_main;
116 u64 t = nm->cpu_time_next_process_ready;
118 int timeout_ms, max_timeout_ms = 10;
119 f64 vector_rate = vlib_last_vectors_per_main_loop (vm);
124 timeout_ms = max_timeout_ms;
129 (((i64) t - (i64) clib_cpu_time_now ())
130 * vm->clib_time.seconds_per_clock)
131 /* subtract off some slop time */ - 50e-6;
135 /* We have event happenning in less than 1 ms so
136 don't allow epoll to wait */
141 timeout_ms = timeout * 1e3;
143 /* Must be between 1 and 10 ms. */
144 timeout_ms = clib_max (1, timeout_ms);
145 timeout_ms = clib_min (max_timeout_ms, timeout_ms);
149 /* If we still have input nodes polling (e.g. vnet packet generator)
151 if (nm->input_node_counts_by_state[VLIB_NODE_STATE_POLLING] > 0)
155 * When busy: don't wait & only epoll for input
156 * every 1024 times through main loop.
158 if (vector_rate > 1 || vm->api_queue_nonempty)
161 node->input_main_loops_per_call = 1024;
164 /* We're not busy; go to sleep for a while. */
165 node->input_main_loops_per_call = 0;
167 /* Allow any signal to wakeup our sleep. */
169 static sigset_t unblock_all_signals;
170 n_fds_ready = epoll_pwait (em->epoll_fd,
172 vec_len (em->epoll_events),
173 timeout_ms, &unblock_all_signals);
175 /* This kludge is necessary to run over absurdly old kernels */
176 if (n_fds_ready < 0 && errno == ENOSYS)
178 n_fds_ready = epoll_wait (em->epoll_fd,
180 vec_len (em->epoll_events), timeout_ms);
187 if (unix_error_is_fatal (errno))
188 vlib_panic_with_error (vm, clib_error_return_unix (0, "epoll_wait"));
190 /* non fatal error (e.g. EINTR). */
194 em->epoll_waits += 1;
195 em->epoll_files_ready += n_fds_ready;
197 for (e = em->epoll_events; e < em->epoll_events + n_fds_ready; e++)
200 unix_file_t *f = pool_elt_at_index (um->file_pool, i);
201 clib_error_t *errors[4];
204 if (PREDICT_TRUE (!(e->events & EPOLLERR)))
206 if (e->events & EPOLLIN)
208 errors[n_errors] = f->read_function (f);
209 n_errors += errors[n_errors] != 0;
211 if (e->events & EPOLLOUT)
213 errors[n_errors] = f->write_function (f);
214 n_errors += errors[n_errors] != 0;
219 if (f->error_function)
221 errors[n_errors] = f->error_function (f);
222 n_errors += errors[n_errors] != 0;
225 close (f->file_descriptor);
228 ASSERT (n_errors < ARRAY_LEN (errors));
229 for (i = 0; i < n_errors; i++)
231 unix_save_error (um, errors[i]);
239 VLIB_REGISTER_NODE (linux_epoll_input_node,static) = {
240 .function = linux_epoll_input,
241 .type = VLIB_NODE_TYPE_PRE_INPUT,
242 .name = "unix-epoll-input",
247 linux_epoll_input_init (vlib_main_t * vm)
249 linux_epoll_main_t *em = &linux_epoll_main;
250 unix_main_t *um = &unix_main;
252 /* Allocate some events. */
253 vec_resize (em->epoll_events, VLIB_FRAME_SIZE);
255 em->epoll_fd = epoll_create (vec_len (em->epoll_events));
256 if (em->epoll_fd < 0)
257 return clib_error_return_unix (0, "epoll_create");
259 um->file_update = linux_epoll_file_update;
264 VLIB_INIT_FUNCTION (linux_epoll_input_init);
266 #endif /* HAVE_LINUX_EPOLL */
268 static clib_error_t *
269 unix_input_init (vlib_main_t * vm)
271 return vlib_call_init_function (vm, linux_epoll_input_init);
274 VLIB_INIT_FUNCTION (unix_input_init);
277 * fd.io coding-style-patch-verification: ON
280 * eval: (c-set-style "gnu")