… | |
… | |
35 | * and other provisions required by the GPL. If you do not delete the |
35 | * and other provisions required by the GPL. If you do not delete the |
36 | * provisions above, a recipient may use your version of this file under |
36 | * provisions above, a recipient may use your version of this file under |
37 | * either the BSD or the GPL. |
37 | * either the BSD or the GPL. |
38 | */ |
38 | */ |
39 | |
39 | |
|
|
40 | #define EPOLL_FALLBACK 1 |
|
|
41 | |
40 | #include <sys/time.h> /* actually linux/time.h, but we must assume they are compatible */ |
42 | #include <sys/time.h> /* actually linux/time.h, but we must assume they are compatible */ |
|
|
43 | #include <poll.h> |
41 | #include <linux/aio_abi.h> |
44 | #include <linux/aio_abi.h> |
42 | |
45 | |
|
|
46 | #if EPOLL_FALLBACK |
|
|
47 | # include <sys/epoll.h> |
|
|
48 | #endif |
|
|
49 | |
43 | /* we try to fill 4kn pages exactly. |
50 | /* we try to fill 4kB pages exactly. |
44 | * the ring buffer header is 32 bytes, every io event is 32 bytes. |
51 | * the ring buffer header is 32 bytes, every io event is 32 bytes. |
45 | * the kernel takes the io event number, doubles it, adds 2, adds the ring buffer |
52 | * the kernel takes the io event number, doubles it, adds 2, adds the ring buffer. |
46 | * so the calculation below will use "exactly" 8kB for the ring buffer |
53 | * therefore the calculation below will use "exactly" 4kB for the ring buffer |
47 | */ |
54 | */ |
48 | #define EV_LINUXAIO_DEPTH (256 / 2 - 2 - 1) /* max. number of io events per batch */ |
55 | #define EV_LINUXAIO_DEPTH (128 / 2 - 2 - 1) /* max. number of io events per batch */ |
49 | |
56 | |
50 | /*****************************************************************************/ |
57 | /*****************************************************************************/ |
51 | /* syscall wrapdadoop */ |
58 | /* syscall wrapdadoop */ |
52 | |
59 | |
53 | #include <sys/syscall.h> /* no glibc wrappers */ |
60 | #include <sys/syscall.h> /* no glibc wrappers */ |
54 | |
61 | |
55 | /* aio_abi.h is not verioned in any way, so we cannot test for its existance */ |
62 | /* aio_abi.h is not versioned in any way, so we cannot test for its existance */ |
56 | #define IOCB_CMD_POLL 5 |
63 | #define IOCB_CMD_POLL 5 |
57 | |
64 | |
58 | /* taken from linux/fs/aio.c */ |
65 | /* taken from linux/fs/aio.c */ |
59 | #define AIO_RING_MAGIC 0xa10a10a1 |
66 | #define AIO_RING_MAGIC 0xa10a10a1 |
60 | #define AIO_RING_INCOMPAT_FEATURES 0 |
67 | #define AIO_RING_INCOMPAT_FEATURES 0 |
… | |
… | |
71 | unsigned header_length; /* size of aio_ring */ |
78 | unsigned header_length; /* size of aio_ring */ |
72 | |
79 | |
73 | struct io_event io_events[0]; |
80 | struct io_event io_events[0]; |
74 | }; |
81 | }; |
75 | |
82 | |
76 | static int |
83 | inline_size |
|
|
84 | int |
77 | ev_io_setup (unsigned nr_events, aio_context_t *ctx_idp) |
85 | ev_io_setup (unsigned nr_events, aio_context_t *ctx_idp) |
78 | { |
86 | { |
79 | return syscall (SYS_io_setup, nr_events, ctx_idp); |
87 | return syscall (SYS_io_setup, nr_events, ctx_idp); |
80 | } |
88 | } |
81 | |
89 | |
82 | static int |
90 | inline_size |
|
|
91 | int |
83 | ev_io_destroy (aio_context_t ctx_id) |
92 | ev_io_destroy (aio_context_t ctx_id) |
84 | { |
93 | { |
85 | return syscall (SYS_io_destroy, ctx_id); |
94 | return syscall (SYS_io_destroy, ctx_id); |
86 | } |
95 | } |
87 | |
96 | |
88 | static int |
97 | inline_size |
|
|
98 | int |
89 | ev_io_submit (aio_context_t ctx_id, long nr, struct iocb *cbp[]) |
99 | ev_io_submit (aio_context_t ctx_id, long nr, struct iocb *cbp[]) |
90 | { |
100 | { |
91 | return syscall (SYS_io_submit, ctx_id, nr, cbp); |
101 | return syscall (SYS_io_submit, ctx_id, nr, cbp); |
92 | } |
102 | } |
93 | |
103 | |
94 | static int |
104 | inline_size |
|
|
105 | int |
95 | ev_io_cancel (aio_context_t ctx_id, struct iocb *cbp, struct io_event *result) |
106 | ev_io_cancel (aio_context_t ctx_id, struct iocb *cbp, struct io_event *result) |
96 | { |
107 | { |
97 | return syscall (SYS_io_cancel, ctx_id, cbp, result); |
108 | return syscall (SYS_io_cancel, ctx_id, cbp, result); |
98 | } |
109 | } |
99 | |
110 | |
100 | static int |
111 | inline_size |
|
|
112 | int |
101 | ev_io_getevents (aio_context_t ctx_id, long min_nr, long nr, struct io_event *events, struct timespec *timeout) |
113 | ev_io_getevents (aio_context_t ctx_id, long min_nr, long nr, struct io_event *events, struct timespec *timeout) |
102 | { |
114 | { |
103 | return syscall (SYS_io_getevents, ctx_id, min_nr, nr, events, timeout); |
115 | return syscall (SYS_io_getevents, ctx_id, min_nr, nr, events, timeout); |
104 | } |
116 | } |
105 | |
|
|
106 | typedef void (*ev_io_cb) (long nr, struct io_event *events); |
|
|
107 | |
117 | |
108 | /*****************************************************************************/ |
118 | /*****************************************************************************/ |
109 | /* actual backed implementation */ |
119 | /* actual backed implementation */ |
110 | |
120 | |
111 | /* two iocbs for every fd, one for read, one for write */ |
121 | /* we use out own wrapper structure in acse we ever want to do something "clever" */ |
112 | typedef struct aniocb |
122 | typedef struct aniocb |
113 | { |
123 | { |
114 | struct iocb io; |
124 | struct iocb io; |
115 | /*int inuse;*/ |
125 | /*int inuse;*/ |
116 | } *ANIOCBP; |
126 | } *ANIOCBP; |
117 | |
127 | |
118 | inline_size |
128 | inline_size |
119 | void |
129 | void |
120 | linuxaio_array_needsize_iocbp (ANIOCBP *base, int count) |
130 | linuxaio_array_needsize_iocbp (ANIOCBP *base, int count) |
121 | { |
131 | { |
122 | /* TODO: quite the overhead to allocate every iocb separately */ |
132 | /* TODO: quite the overhead to allocate every iocb separately, maybe use our own alocator? */ |
123 | while (count--) |
133 | while (count--) |
124 | { |
134 | { |
125 | *base = (ANIOCBP)ev_malloc (sizeof (**base)); |
135 | *base = (ANIOCBP)ev_malloc (sizeof (**base)); |
|
|
136 | /* TODO: full zero initialize required? */ |
126 | memset (*base, 0, sizeof (**base)); |
137 | memset (*base, 0, sizeof (**base)); |
127 | /* would be nice to initialize fd/data as well */ |
138 | /* would be nice to initialize fd/data as well, but array_needsize API doesn't support that */ |
128 | (*base)->io.aio_lio_opcode = IOCB_CMD_POLL; |
139 | (*base)->io.aio_lio_opcode = IOCB_CMD_POLL; |
129 | ++base; |
140 | ++base; |
130 | } |
141 | } |
131 | } |
142 | } |
132 | |
143 | |
|
|
144 | ecb_cold |
133 | static void |
145 | static void |
134 | linuxaio_free_iocbp (EV_P) |
146 | linuxaio_free_iocbp (EV_P) |
135 | { |
147 | { |
136 | while (linuxaio_iocbpmax--) |
148 | while (linuxaio_iocbpmax--) |
137 | ev_free (linuxaio_iocbps [linuxaio_iocbpmax]); |
149 | ev_free (linuxaio_iocbps [linuxaio_iocbpmax]); |
138 | |
150 | |
139 | linuxaio_iocbpmax = 0; |
151 | linuxaio_iocbpmax = 0; /* next resize will completely reallocate the array, at some overhead */ |
140 | } |
152 | } |
141 | |
153 | |
142 | static void |
154 | static void |
143 | linuxaio_modify (EV_P_ int fd, int oev, int nev) |
155 | linuxaio_modify (EV_P_ int fd, int oev, int nev) |
144 | { |
156 | { |
145 | /* TODO: full zero initialize required? */ |
|
|
146 | array_needsize (ANIOCBP, linuxaio_iocbps, linuxaio_iocbpmax, fd + 1, linuxaio_array_needsize_iocbp); |
157 | array_needsize (ANIOCBP, linuxaio_iocbps, linuxaio_iocbpmax, fd + 1, linuxaio_array_needsize_iocbp); |
147 | struct aniocb *iocb = linuxaio_iocbps [fd]; |
158 | struct aniocb *iocb = linuxaio_iocbps [fd]; |
148 | |
159 | |
|
|
160 | #if EPOLL_FALLBACK |
|
|
161 | if (iocb->io.aio_reqprio < 0) |
|
|
162 | { |
|
|
163 | epoll_ctl (backend_fd, EPOLL_CTL_DEL, fd, 0); |
|
|
164 | iocb->io.aio_reqprio = 0; |
|
|
165 | } |
|
|
166 | #endif |
|
|
167 | |
149 | if (iocb->io.aio_buf) |
168 | if (iocb->io.aio_buf) |
150 | ev_io_cancel (linuxaio_ctx, &iocb->io, (void *)0); |
169 | ev_io_cancel (linuxaio_ctx, &iocb->io, (struct io_event *)0); /* always returns an error relevant kernels */ |
151 | |
170 | |
152 | if (nev) |
171 | if (nev) |
153 | { |
172 | { |
154 | iocb->io.aio_data = fd; |
173 | iocb->io.aio_data = fd; |
155 | iocb->io.aio_fildes = fd; |
174 | iocb->io.aio_fildes = fd; |
… | |
… | |
171 | while (nr) |
190 | while (nr) |
172 | { |
191 | { |
173 | int fd = ev->data; |
192 | int fd = ev->data; |
174 | int res = ev->res; |
193 | int res = ev->res; |
175 | |
194 | |
176 | assert (("libev: iocb fd must be in-bounds", fd >= 0 && fd < anfdxmax)); |
195 | assert (("libev: iocb fd must be in-bounds", fd >= 0 && fd < anfdmax)); |
177 | |
196 | |
178 | /* linux aio is oneshot: rearm fd */ |
197 | /* linux aio is oneshot: rearm fd */ |
179 | linuxaio_iocbps [fd]->io.aio_buf = 0; |
198 | linuxaio_iocbps [fd]->io.aio_buf = 0; |
180 | anfds [fd].events = 0; |
199 | anfds [fd].events = 0; |
181 | fd_change (EV_A_ fd, 0); |
200 | fd_change (EV_A_ fd, 0); |
182 | |
201 | |
183 | /* feed events, we do not expect or handle POLLNVAL */ |
202 | /* feed events, we do not expect or handle POLLNVAL */ |
184 | if (ecb_expect_false (res & POLLNVAL)) |
203 | if (expect_false (res & POLLNVAL)) |
185 | fd_kill (EV_A_ fd); |
204 | fd_kill (EV_A_ fd); |
186 | else |
205 | else |
187 | fd_event ( |
206 | fd_event ( |
188 | EV_A_ |
207 | EV_A_ |
189 | fd, |
208 | fd, |
… | |
… | |
200 | static int |
219 | static int |
201 | linuxaio_get_events_from_ring (EV_P) |
220 | linuxaio_get_events_from_ring (EV_P) |
202 | { |
221 | { |
203 | struct aio_ring *ring = (struct aio_ring *)linuxaio_ctx; |
222 | struct aio_ring *ring = (struct aio_ring *)linuxaio_ctx; |
204 | |
223 | |
|
|
224 | /* the kernel reads and writes both of these variables, */ |
|
|
225 | /* as a C extension, we assume that volatile use here */ |
|
|
226 | /* both makes reads atomic and once-only */ |
|
|
227 | unsigned head = *(volatile unsigned *)&ring->head; |
|
|
228 | unsigned tail = *(volatile unsigned *)&ring->tail; |
|
|
229 | |
|
|
230 | if (head == tail) |
|
|
231 | return 0; |
|
|
232 | |
|
|
233 | /* bail out if the ring buffer doesn't match the expected layout */ |
|
|
234 | if (expect_false (ring->magic != AIO_RING_MAGIC) |
|
|
235 | || ring->incompat_features != AIO_RING_INCOMPAT_FEATURES |
|
|
236 | || ring->header_length != sizeof (struct aio_ring)) /* TODO: or use it to find io_event[0]? */ |
|
|
237 | return 0; |
|
|
238 | |
|
|
239 | /* make sure the events up to tail are visible */ |
205 | ECB_MEMORY_FENCE_ACQUIRE; |
240 | ECB_MEMORY_FENCE_ACQUIRE; |
206 | |
|
|
207 | unsigned head = ring->head; |
|
|
208 | unsigned tail = *(volatile unsigned *)&ring->tail; |
|
|
209 | |
|
|
210 | if (ring->magic != AIO_RING_MAGIC |
|
|
211 | || ring->incompat_features != AIO_RING_INCOMPAT_FEATURES |
|
|
212 | || ring->header_length != sizeof (struct aio_ring) /* TODO: or use it to find io_event[0]? */ |
|
|
213 | || head == tail) |
|
|
214 | return 0; |
|
|
215 | |
241 | |
216 | /* parse all available events, but only once, to avoid starvation */ |
242 | /* parse all available events, but only once, to avoid starvation */ |
217 | if (tail > head) /* normal case around */ |
243 | if (tail > head) /* normal case around */ |
218 | linuxaio_parse_events (EV_A_ ring->io_events + head, tail - head); |
244 | linuxaio_parse_events (EV_A_ ring->io_events + head, tail - head); |
219 | else |
|
|
220 | { |
|
|
221 | /* wrapped around */ |
245 | else /* wrapped around */ |
|
|
246 | { |
222 | linuxaio_parse_events (EV_A_ ring->io_events + head, ring->nr - head); |
247 | linuxaio_parse_events (EV_A_ ring->io_events + head, ring->nr - head); |
223 | linuxaio_parse_events (EV_A_ ring->io_events, tail); |
248 | linuxaio_parse_events (EV_A_ ring->io_events, tail); |
224 | } |
249 | } |
225 | |
250 | |
226 | ring->head = tail; |
251 | /* TODO: we only need a compiler barrier here, not a read fence */ |
|
|
252 | ECB_MEMORY_FENCE_RELEASE; |
|
|
253 | /* as an extension to C, we hope that the volatile will make this atomic and once-only */ |
|
|
254 | *(volatile unsigned *)&ring->head = tail; |
|
|
255 | /* make sure kernel can see our new head value - probably not required */ |
|
|
256 | ECB_MEMORY_FENCE_RELEASE; |
227 | |
257 | |
228 | return 1; |
258 | return 1; |
229 | } |
259 | } |
230 | |
260 | |
231 | /* read at least one event from kernel, or timeout */ |
261 | /* read at least one event from kernel, or timeout */ |
… | |
… | |
239 | |
269 | |
240 | if (linuxaio_get_events_from_ring (EV_A)) |
270 | if (linuxaio_get_events_from_ring (EV_A)) |
241 | return; |
271 | return; |
242 | |
272 | |
243 | /* no events, so wait for at least one, then poll ring buffer again */ |
273 | /* no events, so wait for at least one, then poll ring buffer again */ |
244 | /* this degraded to one event per loop iteration */ |
274 | /* this degrades to one event per loop iteration */ |
245 | /* if the ring buffer changes layout, but so be it */ |
275 | /* if the ring buffer changes layout, but so be it */ |
246 | |
276 | |
247 | ts.tv_sec = (long)timeout; |
277 | ts.tv_sec = (long)timeout; |
248 | ts.tv_nsec = (long)((timeout - ts.tv_sec) * 1e9); |
278 | ts.tv_nsec = (long)((timeout - ts.tv_sec) * 1e9); |
249 | |
279 | |
250 | res = ev_io_getevents (linuxaio_ctx, 1, 1, &ioev, &ts); |
280 | res = ev_io_getevents (linuxaio_ctx, 1, 1, &ioev, &ts); |
251 | |
281 | |
252 | if (res < 0) |
282 | if (res < 0) |
|
|
283 | if (errno == EINTR) |
|
|
284 | /* ignored */; |
|
|
285 | else |
253 | ev_syserr ("(libev) io_getevents"); |
286 | ev_syserr ("(libev) linuxaio io_getevents"); |
254 | else if (res) |
287 | else if (res) |
255 | { |
288 | { |
256 | /* at least one event received, handle it and any remaining ones in the ring buffer */ |
289 | /* at least one event received, handle it and any remaining ones in the ring buffer */ |
257 | linuxaio_parse_events (EV_A_ &ioev, 1); |
290 | linuxaio_parse_events (EV_A_ &ioev, 1); |
258 | linuxaio_get_events_from_ring (EV_A); |
291 | linuxaio_get_events_from_ring (EV_A); |
259 | } |
292 | } |
260 | } |
293 | } |
|
|
294 | |
|
|
295 | #if EPOLL_FALLBACK |
|
|
296 | static void |
|
|
297 | linuxaio_rearm_epoll (EV_P_ struct iocb *iocb, int op) |
|
|
298 | { |
|
|
299 | struct epoll_event eev; |
|
|
300 | |
|
|
301 | eev.events = EPOLLONESHOT; |
|
|
302 | if (iocb->aio_buf & POLLIN ) eev.events |= EPOLLIN ; |
|
|
303 | if (iocb->aio_buf & POLLOUT) eev.events |= EPOLLOUT; |
|
|
304 | eev.data.fd = iocb->aio_fildes; |
|
|
305 | |
|
|
306 | if (epoll_ctl (backend_fd, op, iocb->aio_fildes, &eev) < 0) |
|
|
307 | ev_syserr ("(libeio) linuxaio epoll_ctl"); |
|
|
308 | } |
|
|
309 | #endif |
261 | |
310 | |
262 | static void |
311 | static void |
263 | linuxaio_poll (EV_P_ ev_tstamp timeout) |
312 | linuxaio_poll (EV_P_ ev_tstamp timeout) |
264 | { |
313 | { |
265 | int submitted; |
314 | int submitted; |
… | |
… | |
271 | /* which allows us to pinpoint the errornous iocb */ |
320 | /* which allows us to pinpoint the errornous iocb */ |
272 | for (submitted = 0; submitted < linuxaio_submitcnt; ) |
321 | for (submitted = 0; submitted < linuxaio_submitcnt; ) |
273 | { |
322 | { |
274 | int res = ev_io_submit (linuxaio_ctx, linuxaio_submitcnt - submitted, linuxaio_submits + submitted); |
323 | int res = ev_io_submit (linuxaio_ctx, linuxaio_submitcnt - submitted, linuxaio_submits + submitted); |
275 | |
324 | |
276 | if (res < 0) |
325 | if (expect_false (res < 0)) |
277 | if (errno == EAGAIN) |
326 | if (errno == EAGAIN) |
278 | { |
327 | { |
279 | /* This happens when the ring buffer is full, at least. I assume this means |
328 | /* This happens when the ring buffer is full, at least. I assume this means |
280 | * that the event was queued synchronously during io_submit, and thus |
329 | * that the event was queued synchronously during io_submit, and thus |
281 | * the buffer overflowd. |
330 | * the buffer overflowed. |
282 | * In this case, we just try next loop iteration. |
331 | * In this case, we just try in next loop iteration. |
|
|
332 | * This should not result in a few fds taking priority, as the interface |
|
|
333 | * is one-shot, and we submit iocb's in a round-robin fashion. |
283 | */ |
334 | */ |
284 | memcpy (linuxaio_submits, linuxaio_submits + submitted, (linuxaio_submitcnt - submitted) * sizeof (*linuxaio_submits)); |
335 | memmove (linuxaio_submits, linuxaio_submits + submitted, (linuxaio_submitcnt - submitted) * sizeof (*linuxaio_submits)); |
285 | linuxaio_submitcnt -= submitted; |
336 | linuxaio_submitcnt -= submitted; |
286 | timeout = 0; |
337 | timeout = 0; |
287 | break; |
338 | break; |
288 | } |
339 | } |
|
|
340 | #if EPOLL_FALLBACK |
|
|
341 | else if (errno == EINVAL) |
|
|
342 | { |
|
|
343 | /* This happens for unsupported fds, officially, but in my testing, |
|
|
344 | * also randomly happens for supported fds. We fall back to good old |
|
|
345 | * poll() here, under the assumption that this is a very rare case. |
|
|
346 | * See https://lore.kernel.org/patchwork/patch/1047453/ for evidence |
|
|
347 | * that the problem is known, but ignored. |
|
|
348 | */ |
|
|
349 | struct iocb *iocb = linuxaio_submits [submitted]; |
|
|
350 | res = 1; /* skip this iocb */ |
|
|
351 | |
|
|
352 | linuxaio_rearm_epoll (EV_A_ iocb, EPOLL_CTL_ADD); |
|
|
353 | iocb->aio_reqprio = -1; /* mark iocb as epoll */ |
|
|
354 | } |
|
|
355 | #endif |
289 | else |
356 | else |
290 | /* TODO: we get EAGAIN when the ring buffer is full for some reason */ |
|
|
291 | /* TODO: should we always just try next time? */ |
|
|
292 | ev_syserr ("(libev) io_submit"); |
357 | ev_syserr ("(libev) linuxaio io_submit"); |
293 | |
358 | |
294 | submitted += res; |
359 | submitted += res; |
295 | } |
360 | } |
296 | |
361 | |
297 | linuxaio_submitcnt = 0; |
362 | linuxaio_submitcnt = 0; |
… | |
… | |
299 | /* second phase: fetch and parse events */ |
364 | /* second phase: fetch and parse events */ |
300 | |
365 | |
301 | linuxaio_get_events (EV_A_ timeout); |
366 | linuxaio_get_events (EV_A_ timeout); |
302 | } |
367 | } |
303 | |
368 | |
|
|
369 | #if EPOLL_FALLBACK |
|
|
370 | |
|
|
371 | static void |
|
|
372 | linuxaio_epoll_cb (EV_P_ struct ev_io *w, int revents) |
|
|
373 | { |
|
|
374 | struct epoll_event events[16]; |
|
|
375 | |
|
|
376 | for (;;) |
|
|
377 | { |
|
|
378 | int idx; |
|
|
379 | int res = epoll_wait (backend_fd, events, sizeof (events) / sizeof (events [0]), 0); |
|
|
380 | |
|
|
381 | if (expect_false (res < 0)) |
|
|
382 | ev_syserr ("(libev) linuxaio epoll_wait"); |
|
|
383 | else if (!res) |
|
|
384 | break; |
|
|
385 | |
|
|
386 | for (idx = res; idx--; ) |
|
|
387 | { |
|
|
388 | int fd = events [idx].data.fd; |
|
|
389 | uint32_t ev = events [idx].events; |
|
|
390 | |
|
|
391 | assert (("libev: iocb fd must be in-bounds", fd >= 0 && fd < anfdmax)); |
|
|
392 | |
|
|
393 | linuxaio_rearm_epoll (EV_A_ &linuxaio_iocbps [fd]->io, EPOLL_CTL_MOD); |
|
|
394 | |
|
|
395 | fd_event (EV_A_ fd, |
|
|
396 | (ev & (EPOLLOUT | EPOLLERR | EPOLLHUP) ? EV_WRITE : 0) |
|
|
397 | | (ev & (EPOLLIN | EPOLLERR | EPOLLHUP) ? EV_READ : 0)); |
|
|
398 | } |
|
|
399 | |
|
|
400 | if (res < sizeof (events) / sizeof (events [0])) |
|
|
401 | break; |
|
|
402 | } |
|
|
403 | } |
|
|
404 | |
|
|
405 | #endif |
|
|
406 | |
304 | inline_size |
407 | inline_size |
305 | int |
408 | int |
306 | linuxaio_init (EV_P_ int flags) |
409 | linuxaio_init (EV_P_ int flags) |
307 | { |
410 | { |
308 | /* would be great to have a nice test for IOCB_CMD_POLL instead */ |
411 | /* would be great to have a nice test for IOCB_CMD_POLL instead */ |
309 | if (ev_linux_version () < 0x041200) /* 4.18 introduced IOCB_CMD_POLL */ |
412 | /* also: test some semi-common fd types, such as files and ttys in recommended_backends */ |
|
|
413 | #if EPOLL_FALLBACK |
|
|
414 | /* 4.19 made epoll work */ |
|
|
415 | if (ev_linux_version () < 0x041300) |
310 | return 0; |
416 | return 0; |
|
|
417 | #else |
|
|
418 | /* 4.18 introduced IOCB_CMD_POLL */ |
|
|
419 | if (ev_linux_version () < 0x041200) |
|
|
420 | return 0; |
|
|
421 | #endif |
311 | |
422 | |
|
|
423 | linuxaio_ctx = 0; |
312 | if (ev_io_setup (EV_LINUXAIO_DEPTH, &linuxaio_ctx) < 0) |
424 | if (ev_io_setup (EV_LINUXAIO_DEPTH, &linuxaio_ctx) < 0) |
313 | return 0; |
425 | return 0; |
|
|
426 | |
|
|
427 | #if EPOLL_FALLBACK |
|
|
428 | backend_fd = ev_epoll_create (); |
|
|
429 | if (backend_fd < 0) |
|
|
430 | { |
|
|
431 | ev_io_destroy (linuxaio_ctx); |
|
|
432 | return 0; |
|
|
433 | } |
|
|
434 | |
|
|
435 | ev_io_init (EV_A_ &linuxaio_epoll_w, linuxaio_epoll_cb, backend_fd, EV_READ); |
|
|
436 | ev_io_start (EV_A_ &linuxaio_epoll_w); |
|
|
437 | ev_unref (EV_A); /* watcher should not keep loop alive */ |
|
|
438 | #endif |
314 | |
439 | |
315 | backend_modify = linuxaio_modify; |
440 | backend_modify = linuxaio_modify; |
316 | backend_poll = linuxaio_poll; |
441 | backend_poll = linuxaio_poll; |
317 | |
442 | |
318 | linuxaio_iocbpmax = 0; |
443 | linuxaio_iocbpmax = 0; |
… | |
… | |
327 | |
452 | |
328 | inline_size |
453 | inline_size |
329 | void |
454 | void |
330 | linuxaio_destroy (EV_P) |
455 | linuxaio_destroy (EV_P) |
331 | { |
456 | { |
|
|
457 | #if EPOLL_FALLBACK |
|
|
458 | close (backend_fd); |
|
|
459 | #endif |
332 | linuxaio_free_iocbp (EV_A); |
460 | linuxaio_free_iocbp (EV_A); |
333 | ev_io_destroy (linuxaio_ctx); |
461 | ev_io_destroy (linuxaio_ctx); |
334 | } |
462 | } |
335 | |
463 | |
336 | inline_size |
464 | inline_size |
337 | void |
465 | void |
338 | linuxaio_fork (EV_P) |
466 | linuxaio_fork (EV_P) |
339 | { |
467 | { |
340 | abort ();//D |
468 | /* this frees all iocbs, which is very heavy-handed */ |
341 | } |
469 | linuxaio_destroy (EV_A); |
|
|
470 | linuxaio_submitcnt = 0; /* all pointers were invalidated */ |
342 | |
471 | |
|
|
472 | linuxaio_ctx = 0; |
|
|
473 | while (ev_io_setup (EV_LINUXAIO_DEPTH, &linuxaio_ctx) < 0) |
|
|
474 | ev_syserr ("(libev) linuxaio io_setup"); |
|
|
475 | |
|
|
476 | #if EPOLL_FALLBACK |
|
|
477 | while ((backend_fd = ev_epoll_create ()) < 0) |
|
|
478 | ev_syserr ("(libev) linuxaio epoll_create"); |
|
|
479 | |
|
|
480 | ev_io_stop (EV_A_ &linuxaio_epoll_w); |
|
|
481 | ev_io_init (EV_A_ &linuxaio_epoll_w, linuxaio_epoll_cb, backend_fd, EV_READ); |
|
|
482 | ev_io_start (EV_A_ &linuxaio_epoll_w); |
|
|
483 | #endif |
|
|
484 | |
|
|
485 | fd_rearm_all (EV_A); |
|
|
486 | } |
|
|
487 | |