Christopher Wiley | e867981 | 2015-07-01 13:36:18 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Copyright 2000-2007 Niels Provos <provos@citi.umich.edu> |
| 3 | * Copyright 2007-2012 Niels Provos, Nick Mathewson |
| 4 | * |
| 5 | * Redistribution and use in source and binary forms, with or without |
| 6 | * modification, are permitted provided that the following conditions |
| 7 | * are met: |
| 8 | * 1. Redistributions of source code must retain the above copyright |
| 9 | * notice, this list of conditions and the following disclaimer. |
| 10 | * 2. Redistributions in binary form must reproduce the above copyright |
| 11 | * notice, this list of conditions and the following disclaimer in the |
| 12 | * documentation and/or other materials provided with the distribution. |
| 13 | * 3. The name of the author may not be used to endorse or promote products |
| 14 | * derived from this software without specific prior written permission. |
| 15 | * |
| 16 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
| 17 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
| 18 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
| 19 | * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
| 20 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
| 21 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| 22 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| 23 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| 24 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
| 25 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| 26 | */ |
| 27 | #include "event2/event-config.h" |
Narayan Kamath | fc74cb4 | 2017-09-13 12:53:52 +0100 | [diff] [blame] | 28 | #include "evconfig-private.h" |
| 29 | |
| 30 | #ifdef EVENT__HAVE_EPOLL |
Christopher Wiley | e867981 | 2015-07-01 13:36:18 -0700 | [diff] [blame] | 31 | |
| 32 | #include <stdint.h> |
| 33 | #include <sys/types.h> |
| 34 | #include <sys/resource.h> |
Narayan Kamath | fc74cb4 | 2017-09-13 12:53:52 +0100 | [diff] [blame] | 35 | #ifdef EVENT__HAVE_SYS_TIME_H |
Christopher Wiley | e867981 | 2015-07-01 13:36:18 -0700 | [diff] [blame] | 36 | #include <sys/time.h> |
| 37 | #endif |
| 38 | #include <sys/queue.h> |
| 39 | #include <sys/epoll.h> |
| 40 | #include <signal.h> |
| 41 | #include <limits.h> |
| 42 | #include <stdio.h> |
| 43 | #include <stdlib.h> |
| 44 | #include <string.h> |
| 45 | #include <unistd.h> |
| 46 | #include <errno.h> |
Narayan Kamath | fc74cb4 | 2017-09-13 12:53:52 +0100 | [diff] [blame] | 47 | #ifdef EVENT__HAVE_FCNTL_H |
Christopher Wiley | e867981 | 2015-07-01 13:36:18 -0700 | [diff] [blame] | 48 | #include <fcntl.h> |
| 49 | #endif |
Narayan Kamath | fc74cb4 | 2017-09-13 12:53:52 +0100 | [diff] [blame] | 50 | #ifdef EVENT__HAVE_SYS_TIMERFD_H |
| 51 | #include <sys/timerfd.h> |
| 52 | #endif |
Christopher Wiley | e867981 | 2015-07-01 13:36:18 -0700 | [diff] [blame] | 53 | |
| 54 | #include "event-internal.h" |
| 55 | #include "evsignal-internal.h" |
| 56 | #include "event2/thread.h" |
| 57 | #include "evthread-internal.h" |
| 58 | #include "log-internal.h" |
| 59 | #include "evmap-internal.h" |
| 60 | #include "changelist-internal.h" |
Narayan Kamath | fc74cb4 | 2017-09-13 12:53:52 +0100 | [diff] [blame] | 61 | #include "time-internal.h" |
| 62 | |
| 63 | /* Since Linux 2.6.17, epoll is able to report about peer half-closed connection |
| 64 | using special EPOLLRDHUP flag on a read event. |
| 65 | */ |
| 66 | #if !defined(EPOLLRDHUP) |
| 67 | #define EPOLLRDHUP 0 |
| 68 | #define EARLY_CLOSE_IF_HAVE_RDHUP 0 |
| 69 | #else |
| 70 | #define EARLY_CLOSE_IF_HAVE_RDHUP EV_FEATURE_EARLY_CLOSE |
| 71 | #endif |
| 72 | |
| 73 | #include "epolltable-internal.h" |
| 74 | |
| 75 | #if defined(EVENT__HAVE_SYS_TIMERFD_H) && \ |
| 76 | defined(EVENT__HAVE_TIMERFD_CREATE) && \ |
| 77 | defined(HAVE_POSIX_MONOTONIC) && defined(TFD_NONBLOCK) && \ |
| 78 | defined(TFD_CLOEXEC) |
| 79 | /* Note that we only use timerfd if TFD_NONBLOCK and TFD_CLOEXEC are available |
| 80 | and working. This means that we can't support it on 2.6.25 (where timerfd |
| 81 | was introduced) or 2.6.26, since 2.6.27 introduced those flags. |
| 82 | */ |
| 83 | #define USING_TIMERFD |
| 84 | #endif |
Christopher Wiley | e867981 | 2015-07-01 13:36:18 -0700 | [diff] [blame] | 85 | |
| 86 | struct epollop { |
| 87 | struct epoll_event *events; |
| 88 | int nevents; |
| 89 | int epfd; |
Narayan Kamath | fc74cb4 | 2017-09-13 12:53:52 +0100 | [diff] [blame] | 90 | #ifdef USING_TIMERFD |
| 91 | int timerfd; |
| 92 | #endif |
Christopher Wiley | e867981 | 2015-07-01 13:36:18 -0700 | [diff] [blame] | 93 | }; |
| 94 | |
| 95 | static void *epoll_init(struct event_base *); |
| 96 | static int epoll_dispatch(struct event_base *, struct timeval *); |
| 97 | static void epoll_dealloc(struct event_base *); |
| 98 | |
| 99 | static const struct eventop epollops_changelist = { |
| 100 | "epoll (with changelist)", |
| 101 | epoll_init, |
Narayan Kamath | fc74cb4 | 2017-09-13 12:53:52 +0100 | [diff] [blame] | 102 | event_changelist_add_, |
| 103 | event_changelist_del_, |
Christopher Wiley | e867981 | 2015-07-01 13:36:18 -0700 | [diff] [blame] | 104 | epoll_dispatch, |
| 105 | epoll_dealloc, |
| 106 | 1, /* need reinit */ |
Narayan Kamath | fc74cb4 | 2017-09-13 12:53:52 +0100 | [diff] [blame] | 107 | EV_FEATURE_ET|EV_FEATURE_O1| EARLY_CLOSE_IF_HAVE_RDHUP, |
Christopher Wiley | e867981 | 2015-07-01 13:36:18 -0700 | [diff] [blame] | 108 | EVENT_CHANGELIST_FDINFO_SIZE |
| 109 | }; |
| 110 | |
| 111 | |
| 112 | static int epoll_nochangelist_add(struct event_base *base, evutil_socket_t fd, |
| 113 | short old, short events, void *p); |
| 114 | static int epoll_nochangelist_del(struct event_base *base, evutil_socket_t fd, |
| 115 | short old, short events, void *p); |
| 116 | |
| 117 | const struct eventop epollops = { |
| 118 | "epoll", |
| 119 | epoll_init, |
| 120 | epoll_nochangelist_add, |
| 121 | epoll_nochangelist_del, |
| 122 | epoll_dispatch, |
| 123 | epoll_dealloc, |
| 124 | 1, /* need reinit */ |
Narayan Kamath | fc74cb4 | 2017-09-13 12:53:52 +0100 | [diff] [blame] | 125 | EV_FEATURE_ET|EV_FEATURE_O1|EV_FEATURE_EARLY_CLOSE, |
Christopher Wiley | e867981 | 2015-07-01 13:36:18 -0700 | [diff] [blame] | 126 | 0 |
| 127 | }; |
| 128 | |
| 129 | #define INITIAL_NEVENT 32 |
| 130 | #define MAX_NEVENT 4096 |
| 131 | |
| 132 | /* On Linux kernels at least up to 2.6.24.4, epoll can't handle timeout |
| 133 | * values bigger than (LONG_MAX - 999ULL)/HZ. HZ in the wild can be |
| 134 | * as big as 1000, and LONG_MAX can be as small as (1<<31)-1, so the |
| 135 | * largest number of msec we can support here is 2147482. Let's |
| 136 | * round that down by 47 seconds. |
| 137 | */ |
| 138 | #define MAX_EPOLL_TIMEOUT_MSEC (35*60*1000) |
| 139 | |
| 140 | static void * |
| 141 | epoll_init(struct event_base *base) |
| 142 | { |
Narayan Kamath | fc74cb4 | 2017-09-13 12:53:52 +0100 | [diff] [blame] | 143 | int epfd = -1; |
Christopher Wiley | e867981 | 2015-07-01 13:36:18 -0700 | [diff] [blame] | 144 | struct epollop *epollop; |
| 145 | |
Narayan Kamath | fc74cb4 | 2017-09-13 12:53:52 +0100 | [diff] [blame] | 146 | #ifdef EVENT__HAVE_EPOLL_CREATE1 |
| 147 | /* First, try the shiny new epoll_create1 interface, if we have it. */ |
| 148 | epfd = epoll_create1(EPOLL_CLOEXEC); |
| 149 | #endif |
| 150 | if (epfd == -1) { |
| 151 | /* Initialize the kernel queue using the old interface. (The |
| 152 | size field is ignored since 2.6.8.) */ |
| 153 | if ((epfd = epoll_create(32000)) == -1) { |
| 154 | if (errno != ENOSYS) |
| 155 | event_warn("epoll_create"); |
| 156 | return (NULL); |
| 157 | } |
| 158 | evutil_make_socket_closeonexec(epfd); |
Christopher Wiley | e867981 | 2015-07-01 13:36:18 -0700 | [diff] [blame] | 159 | } |
| 160 | |
Christopher Wiley | e867981 | 2015-07-01 13:36:18 -0700 | [diff] [blame] | 161 | if (!(epollop = mm_calloc(1, sizeof(struct epollop)))) { |
| 162 | close(epfd); |
| 163 | return (NULL); |
| 164 | } |
| 165 | |
| 166 | epollop->epfd = epfd; |
| 167 | |
| 168 | /* Initialize fields */ |
| 169 | epollop->events = mm_calloc(INITIAL_NEVENT, sizeof(struct epoll_event)); |
| 170 | if (epollop->events == NULL) { |
| 171 | mm_free(epollop); |
| 172 | close(epfd); |
| 173 | return (NULL); |
| 174 | } |
| 175 | epollop->nevents = INITIAL_NEVENT; |
| 176 | |
| 177 | if ((base->flags & EVENT_BASE_FLAG_EPOLL_USE_CHANGELIST) != 0 || |
| 178 | ((base->flags & EVENT_BASE_FLAG_IGNORE_ENV) == 0 && |
Narayan Kamath | fc74cb4 | 2017-09-13 12:53:52 +0100 | [diff] [blame] | 179 | evutil_getenv_("EVENT_EPOLL_USE_CHANGELIST") != NULL)) { |
Elliott Hughes | 2a572d1 | 2017-08-07 14:18:18 -0700 | [diff] [blame] | 180 | |
Narayan Kamath | fc74cb4 | 2017-09-13 12:53:52 +0100 | [diff] [blame] | 181 | base->evsel = &epollops_changelist; |
| 182 | } |
| 183 | |
| 184 | #ifdef USING_TIMERFD |
| 185 | /* |
| 186 | The epoll interface ordinarily gives us one-millisecond precision, |
| 187 | so on Linux it makes perfect sense to use the CLOCK_MONOTONIC_COARSE |
| 188 | timer. But when the user has set the new PRECISE_TIMER flag for an |
| 189 | event_base, we can try to use timerfd to give them finer granularity. |
| 190 | */ |
| 191 | if ((base->flags & EVENT_BASE_FLAG_PRECISE_TIMER) && |
| 192 | base->monotonic_timer.monotonic_clock == CLOCK_MONOTONIC) { |
| 193 | int fd; |
| 194 | fd = epollop->timerfd = timerfd_create(CLOCK_MONOTONIC, TFD_NONBLOCK|TFD_CLOEXEC); |
| 195 | if (epollop->timerfd >= 0) { |
| 196 | struct epoll_event epev; |
| 197 | memset(&epev, 0, sizeof(epev)); |
| 198 | epev.data.fd = epollop->timerfd; |
| 199 | epev.events = EPOLLIN; |
| 200 | if (epoll_ctl(epollop->epfd, EPOLL_CTL_ADD, fd, &epev) < 0) { |
| 201 | event_warn("epoll_ctl(timerfd)"); |
| 202 | close(fd); |
| 203 | epollop->timerfd = -1; |
| 204 | } |
| 205 | } else { |
| 206 | if (errno != EINVAL && errno != ENOSYS) { |
| 207 | /* These errors probably mean that we were |
| 208 | * compiled with timerfd/TFD_* support, but |
| 209 | * we're running on a kernel that lacks those. |
| 210 | */ |
| 211 | event_warn("timerfd_create"); |
| 212 | } |
| 213 | epollop->timerfd = -1; |
| 214 | } |
| 215 | } else { |
| 216 | epollop->timerfd = -1; |
| 217 | } |
| 218 | #endif |
| 219 | |
| 220 | evsig_init_(base); |
Christopher Wiley | e867981 | 2015-07-01 13:36:18 -0700 | [diff] [blame] | 221 | |
| 222 | return (epollop); |
| 223 | } |
| 224 | |
| 225 | static const char * |
| 226 | change_to_string(int change) |
| 227 | { |
| 228 | change &= (EV_CHANGE_ADD|EV_CHANGE_DEL); |
| 229 | if (change == EV_CHANGE_ADD) { |
| 230 | return "add"; |
| 231 | } else if (change == EV_CHANGE_DEL) { |
| 232 | return "del"; |
| 233 | } else if (change == 0) { |
| 234 | return "none"; |
| 235 | } else { |
| 236 | return "???"; |
| 237 | } |
| 238 | } |
| 239 | |
| 240 | static const char * |
| 241 | epoll_op_to_string(int op) |
| 242 | { |
| 243 | return op == EPOLL_CTL_ADD?"ADD": |
| 244 | op == EPOLL_CTL_DEL?"DEL": |
| 245 | op == EPOLL_CTL_MOD?"MOD": |
| 246 | "???"; |
| 247 | } |
| 248 | |
Narayan Kamath | fc74cb4 | 2017-09-13 12:53:52 +0100 | [diff] [blame] | 249 | #define PRINT_CHANGES(op, events, ch, status) \ |
| 250 | "Epoll %s(%d) on fd %d " status ". " \ |
| 251 | "Old events were %d; " \ |
| 252 | "read change was %d (%s); " \ |
| 253 | "write change was %d (%s); " \ |
| 254 | "close change was %d (%s)", \ |
| 255 | epoll_op_to_string(op), \ |
| 256 | events, \ |
| 257 | ch->fd, \ |
| 258 | ch->old_events, \ |
| 259 | ch->read_change, \ |
| 260 | change_to_string(ch->read_change), \ |
| 261 | ch->write_change, \ |
| 262 | change_to_string(ch->write_change), \ |
| 263 | ch->close_change, \ |
| 264 | change_to_string(ch->close_change) |
| 265 | |
Christopher Wiley | e867981 | 2015-07-01 13:36:18 -0700 | [diff] [blame] | 266 | static int |
| 267 | epoll_apply_one_change(struct event_base *base, |
| 268 | struct epollop *epollop, |
| 269 | const struct event_change *ch) |
| 270 | { |
| 271 | struct epoll_event epev; |
| 272 | int op, events = 0; |
Narayan Kamath | fc74cb4 | 2017-09-13 12:53:52 +0100 | [diff] [blame] | 273 | int idx; |
Christopher Wiley | e867981 | 2015-07-01 13:36:18 -0700 | [diff] [blame] | 274 | |
Narayan Kamath | fc74cb4 | 2017-09-13 12:53:52 +0100 | [diff] [blame] | 275 | idx = EPOLL_OP_TABLE_INDEX(ch); |
| 276 | op = epoll_op_table[idx].op; |
| 277 | events = epoll_op_table[idx].events; |
Christopher Wiley | e867981 | 2015-07-01 13:36:18 -0700 | [diff] [blame] | 278 | |
Narayan Kamath | fc74cb4 | 2017-09-13 12:53:52 +0100 | [diff] [blame] | 279 | if (!events) { |
| 280 | EVUTIL_ASSERT(op == 0); |
| 281 | return 0; |
Josh Gao | 83a0c9c | 2017-08-10 12:30:25 -0700 | [diff] [blame] | 282 | } |
Narayan Kamath | fc74cb4 | 2017-09-13 12:53:52 +0100 | [diff] [blame] | 283 | |
Haibo Huang | f0077b8 | 2020-07-10 20:21:19 -0700 | [diff] [blame] | 284 | if ((ch->read_change|ch->write_change|ch->close_change) & EV_CHANGE_ET) |
Narayan Kamath | fc74cb4 | 2017-09-13 12:53:52 +0100 | [diff] [blame] | 285 | events |= EPOLLET; |
| 286 | |
| 287 | memset(&epev, 0, sizeof(epev)); |
| 288 | epev.data.fd = ch->fd; |
| 289 | epev.events = events; |
| 290 | if (epoll_ctl(epollop->epfd, op, ch->fd, &epev) == 0) { |
| 291 | event_debug((PRINT_CHANGES(op, epev.events, ch, "okay"))); |
| 292 | return 0; |
| 293 | } |
| 294 | |
| 295 | switch (op) { |
| 296 | case EPOLL_CTL_MOD: |
| 297 | if (errno == ENOENT) { |
| 298 | /* If a MOD operation fails with ENOENT, the |
| 299 | * fd was probably closed and re-opened. We |
| 300 | * should retry the operation as an ADD. |
| 301 | */ |
| 302 | if (epoll_ctl(epollop->epfd, EPOLL_CTL_ADD, ch->fd, &epev) == -1) { |
| 303 | event_warn("Epoll MOD(%d) on %d retried as ADD; that failed too", |
| 304 | (int)epev.events, ch->fd); |
| 305 | return -1; |
| 306 | } else { |
| 307 | event_debug(("Epoll MOD(%d) on %d retried as ADD; succeeded.", |
| 308 | (int)epev.events, |
| 309 | ch->fd)); |
| 310 | return 0; |
| 311 | } |
| 312 | } |
| 313 | break; |
| 314 | case EPOLL_CTL_ADD: |
| 315 | if (errno == EEXIST) { |
| 316 | /* If an ADD operation fails with EEXIST, |
| 317 | * either the operation was redundant (as with a |
| 318 | * precautionary add), or we ran into a fun |
| 319 | * kernel bug where using dup*() to duplicate the |
| 320 | * same file into the same fd gives you the same epitem |
| 321 | * rather than a fresh one. For the second case, |
| 322 | * we must retry with MOD. */ |
| 323 | if (epoll_ctl(epollop->epfd, EPOLL_CTL_MOD, ch->fd, &epev) == -1) { |
| 324 | event_warn("Epoll ADD(%d) on %d retried as MOD; that failed too", |
| 325 | (int)epev.events, ch->fd); |
| 326 | return -1; |
| 327 | } else { |
| 328 | event_debug(("Epoll ADD(%d) on %d retried as MOD; succeeded.", |
| 329 | (int)epev.events, |
| 330 | ch->fd)); |
| 331 | return 0; |
| 332 | } |
| 333 | } |
| 334 | break; |
| 335 | case EPOLL_CTL_DEL: |
| 336 | if (errno == ENOENT || errno == EBADF || errno == EPERM) { |
| 337 | /* If a delete fails with one of these errors, |
| 338 | * that's fine too: we closed the fd before we |
| 339 | * got around to calling epoll_dispatch. */ |
| 340 | event_debug(("Epoll DEL(%d) on fd %d gave %s: DEL was unnecessary.", |
| 341 | (int)epev.events, |
| 342 | ch->fd, |
| 343 | strerror(errno))); |
| 344 | return 0; |
| 345 | } |
| 346 | break; |
| 347 | default: |
| 348 | break; |
| 349 | } |
| 350 | |
| 351 | event_warn(PRINT_CHANGES(op, epev.events, ch, "failed")); |
| 352 | return -1; |
Christopher Wiley | e867981 | 2015-07-01 13:36:18 -0700 | [diff] [blame] | 353 | } |
| 354 | |
| 355 | static int |
| 356 | epoll_apply_changes(struct event_base *base) |
| 357 | { |
| 358 | struct event_changelist *changelist = &base->changelist; |
| 359 | struct epollop *epollop = base->evbase; |
| 360 | struct event_change *ch; |
| 361 | |
| 362 | int r = 0; |
| 363 | int i; |
| 364 | |
| 365 | for (i = 0; i < changelist->n_changes; ++i) { |
| 366 | ch = &changelist->changes[i]; |
| 367 | if (epoll_apply_one_change(base, epollop, ch) < 0) |
| 368 | r = -1; |
| 369 | } |
| 370 | |
| 371 | return (r); |
| 372 | } |
| 373 | |
| 374 | static int |
| 375 | epoll_nochangelist_add(struct event_base *base, evutil_socket_t fd, |
| 376 | short old, short events, void *p) |
| 377 | { |
| 378 | struct event_change ch; |
| 379 | ch.fd = fd; |
| 380 | ch.old_events = old; |
Narayan Kamath | fc74cb4 | 2017-09-13 12:53:52 +0100 | [diff] [blame] | 381 | ch.read_change = ch.write_change = ch.close_change = 0; |
Christopher Wiley | e867981 | 2015-07-01 13:36:18 -0700 | [diff] [blame] | 382 | if (events & EV_WRITE) |
| 383 | ch.write_change = EV_CHANGE_ADD | |
| 384 | (events & EV_ET); |
| 385 | if (events & EV_READ) |
| 386 | ch.read_change = EV_CHANGE_ADD | |
| 387 | (events & EV_ET); |
Narayan Kamath | fc74cb4 | 2017-09-13 12:53:52 +0100 | [diff] [blame] | 388 | if (events & EV_CLOSED) |
| 389 | ch.close_change = EV_CHANGE_ADD | |
| 390 | (events & EV_ET); |
Christopher Wiley | e867981 | 2015-07-01 13:36:18 -0700 | [diff] [blame] | 391 | |
| 392 | return epoll_apply_one_change(base, base->evbase, &ch); |
| 393 | } |
| 394 | |
| 395 | static int |
| 396 | epoll_nochangelist_del(struct event_base *base, evutil_socket_t fd, |
| 397 | short old, short events, void *p) |
| 398 | { |
| 399 | struct event_change ch; |
| 400 | ch.fd = fd; |
| 401 | ch.old_events = old; |
Narayan Kamath | fc74cb4 | 2017-09-13 12:53:52 +0100 | [diff] [blame] | 402 | ch.read_change = ch.write_change = ch.close_change = 0; |
Christopher Wiley | e867981 | 2015-07-01 13:36:18 -0700 | [diff] [blame] | 403 | if (events & EV_WRITE) |
Haibo Huang | b227967 | 2019-05-31 16:12:39 -0700 | [diff] [blame] | 404 | ch.write_change = EV_CHANGE_DEL | |
| 405 | (events & EV_ET); |
Christopher Wiley | e867981 | 2015-07-01 13:36:18 -0700 | [diff] [blame] | 406 | if (events & EV_READ) |
Haibo Huang | b227967 | 2019-05-31 16:12:39 -0700 | [diff] [blame] | 407 | ch.read_change = EV_CHANGE_DEL | |
| 408 | (events & EV_ET); |
Narayan Kamath | fc74cb4 | 2017-09-13 12:53:52 +0100 | [diff] [blame] | 409 | if (events & EV_CLOSED) |
Haibo Huang | b227967 | 2019-05-31 16:12:39 -0700 | [diff] [blame] | 410 | ch.close_change = EV_CHANGE_DEL | |
| 411 | (events & EV_ET); |
Christopher Wiley | e867981 | 2015-07-01 13:36:18 -0700 | [diff] [blame] | 412 | |
| 413 | return epoll_apply_one_change(base, base->evbase, &ch); |
| 414 | } |
| 415 | |
| 416 | static int |
| 417 | epoll_dispatch(struct event_base *base, struct timeval *tv) |
| 418 | { |
| 419 | struct epollop *epollop = base->evbase; |
| 420 | struct epoll_event *events = epollop->events; |
| 421 | int i, res; |
| 422 | long timeout = -1; |
| 423 | |
Narayan Kamath | fc74cb4 | 2017-09-13 12:53:52 +0100 | [diff] [blame] | 424 | #ifdef USING_TIMERFD |
| 425 | if (epollop->timerfd >= 0) { |
| 426 | struct itimerspec is; |
| 427 | is.it_interval.tv_sec = 0; |
| 428 | is.it_interval.tv_nsec = 0; |
| 429 | if (tv == NULL) { |
| 430 | /* No timeout; disarm the timer. */ |
| 431 | is.it_value.tv_sec = 0; |
| 432 | is.it_value.tv_nsec = 0; |
| 433 | } else { |
| 434 | if (tv->tv_sec == 0 && tv->tv_usec == 0) { |
| 435 | /* we need to exit immediately; timerfd can't |
| 436 | * do that. */ |
| 437 | timeout = 0; |
| 438 | } |
| 439 | is.it_value.tv_sec = tv->tv_sec; |
| 440 | is.it_value.tv_nsec = tv->tv_usec * 1000; |
| 441 | } |
| 442 | /* TODO: we could avoid unnecessary syscalls here by only |
| 443 | calling timerfd_settime when the top timeout changes, or |
| 444 | when we're called with a different timeval. |
| 445 | */ |
| 446 | if (timerfd_settime(epollop->timerfd, 0, &is, NULL) < 0) { |
| 447 | event_warn("timerfd_settime"); |
| 448 | } |
| 449 | } else |
| 450 | #endif |
Christopher Wiley | e867981 | 2015-07-01 13:36:18 -0700 | [diff] [blame] | 451 | if (tv != NULL) { |
Narayan Kamath | fc74cb4 | 2017-09-13 12:53:52 +0100 | [diff] [blame] | 452 | timeout = evutil_tv_to_msec_(tv); |
Christopher Wiley | e867981 | 2015-07-01 13:36:18 -0700 | [diff] [blame] | 453 | if (timeout < 0 || timeout > MAX_EPOLL_TIMEOUT_MSEC) { |
| 454 | /* Linux kernels can wait forever if the timeout is |
| 455 | * too big; see comment on MAX_EPOLL_TIMEOUT_MSEC. */ |
| 456 | timeout = MAX_EPOLL_TIMEOUT_MSEC; |
| 457 | } |
| 458 | } |
| 459 | |
| 460 | epoll_apply_changes(base); |
Narayan Kamath | fc74cb4 | 2017-09-13 12:53:52 +0100 | [diff] [blame] | 461 | event_changelist_remove_all_(&base->changelist, base); |
Christopher Wiley | e867981 | 2015-07-01 13:36:18 -0700 | [diff] [blame] | 462 | |
| 463 | EVBASE_RELEASE_LOCK(base, th_base_lock); |
| 464 | |
| 465 | res = epoll_wait(epollop->epfd, events, epollop->nevents, timeout); |
| 466 | |
| 467 | EVBASE_ACQUIRE_LOCK(base, th_base_lock); |
| 468 | |
| 469 | if (res == -1) { |
| 470 | if (errno != EINTR) { |
| 471 | event_warn("epoll_wait"); |
| 472 | return (-1); |
| 473 | } |
| 474 | |
| 475 | return (0); |
| 476 | } |
| 477 | |
| 478 | event_debug(("%s: epoll_wait reports %d", __func__, res)); |
| 479 | EVUTIL_ASSERT(res <= epollop->nevents); |
| 480 | |
| 481 | for (i = 0; i < res; i++) { |
| 482 | int what = events[i].events; |
| 483 | short ev = 0; |
Narayan Kamath | fc74cb4 | 2017-09-13 12:53:52 +0100 | [diff] [blame] | 484 | #ifdef USING_TIMERFD |
| 485 | if (events[i].data.fd == epollop->timerfd) |
| 486 | continue; |
| 487 | #endif |
Christopher Wiley | e867981 | 2015-07-01 13:36:18 -0700 | [diff] [blame] | 488 | |
Haibo Huang | f0077b8 | 2020-07-10 20:21:19 -0700 | [diff] [blame] | 489 | if (what & EPOLLERR) { |
| 490 | ev = EV_READ | EV_WRITE; |
| 491 | } else if ((what & EPOLLHUP) && !(what & EPOLLRDHUP)) { |
Christopher Wiley | e867981 | 2015-07-01 13:36:18 -0700 | [diff] [blame] | 492 | ev = EV_READ | EV_WRITE; |
| 493 | } else { |
| 494 | if (what & EPOLLIN) |
| 495 | ev |= EV_READ; |
| 496 | if (what & EPOLLOUT) |
| 497 | ev |= EV_WRITE; |
Narayan Kamath | fc74cb4 | 2017-09-13 12:53:52 +0100 | [diff] [blame] | 498 | if (what & EPOLLRDHUP) |
| 499 | ev |= EV_CLOSED; |
Christopher Wiley | e867981 | 2015-07-01 13:36:18 -0700 | [diff] [blame] | 500 | } |
| 501 | |
| 502 | if (!ev) |
| 503 | continue; |
| 504 | |
Narayan Kamath | fc74cb4 | 2017-09-13 12:53:52 +0100 | [diff] [blame] | 505 | evmap_io_active_(base, events[i].data.fd, ev | EV_ET); |
Christopher Wiley | e867981 | 2015-07-01 13:36:18 -0700 | [diff] [blame] | 506 | } |
| 507 | |
| 508 | if (res == epollop->nevents && epollop->nevents < MAX_NEVENT) { |
| 509 | /* We used all of the event space this time. We should |
| 510 | be ready for more events next time. */ |
| 511 | int new_nevents = epollop->nevents * 2; |
| 512 | struct epoll_event *new_events; |
| 513 | |
| 514 | new_events = mm_realloc(epollop->events, |
| 515 | new_nevents * sizeof(struct epoll_event)); |
| 516 | if (new_events) { |
| 517 | epollop->events = new_events; |
| 518 | epollop->nevents = new_nevents; |
| 519 | } |
| 520 | } |
| 521 | |
| 522 | return (0); |
| 523 | } |
| 524 | |
| 525 | |
| 526 | static void |
| 527 | epoll_dealloc(struct event_base *base) |
| 528 | { |
| 529 | struct epollop *epollop = base->evbase; |
| 530 | |
Narayan Kamath | fc74cb4 | 2017-09-13 12:53:52 +0100 | [diff] [blame] | 531 | evsig_dealloc_(base); |
Christopher Wiley | e867981 | 2015-07-01 13:36:18 -0700 | [diff] [blame] | 532 | if (epollop->events) |
| 533 | mm_free(epollop->events); |
| 534 | if (epollop->epfd >= 0) |
| 535 | close(epollop->epfd); |
Narayan Kamath | fc74cb4 | 2017-09-13 12:53:52 +0100 | [diff] [blame] | 536 | #ifdef USING_TIMERFD |
| 537 | if (epollop->timerfd >= 0) |
| 538 | close(epollop->timerfd); |
| 539 | #endif |
Christopher Wiley | e867981 | 2015-07-01 13:36:18 -0700 | [diff] [blame] | 540 | |
| 541 | memset(epollop, 0, sizeof(struct epollop)); |
| 542 | mm_free(epollop); |
| 543 | } |
Narayan Kamath | fc74cb4 | 2017-09-13 12:53:52 +0100 | [diff] [blame] | 544 | |
| 545 | #endif /* EVENT__HAVE_EPOLL */ |