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/cvs/libev/ev_linuxaio.c
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Comparing libev/ev_linuxaio.c (file contents):
Revision 1.38 by root, Mon Jul 1 19:56:30 2019 UTC vs.
Revision 1.42 by root, Mon Jul 1 20:47:38 2019 UTC

… …
286linuxaio_modify (EV_P_ int fd, int oev, int nev) 286linuxaio_modify (EV_P_ int fd, int oev, int nev)
287{ 287{
288 array_needsize (ANIOCBP, linuxaio_iocbps, linuxaio_iocbpmax, fd + 1, linuxaio_array_needsize_iocbp); 288 array_needsize (ANIOCBP, linuxaio_iocbps, linuxaio_iocbpmax, fd + 1, linuxaio_array_needsize_iocbp);
289 ANIOCBP iocb = linuxaio_iocbps [fd]; 289 ANIOCBP iocb = linuxaio_iocbps [fd];
290 290
291 if (iocb->io.aio_reqprio < 0) 291 if (ecb_expect_false (iocb->io.aio_reqprio < 0))
292 { 292 {
293 /* we handed this fd over to epoll, so undo this first */ 293 /* we handed this fd over to epoll, so undo this first */
294 /* we do it manually because the optimisations on epoll_modify won't do us any good */ 294 /* we do it manually because the optimisations on epoll_modify won't do us any good */
295 epoll_ctl (backend_fd, EPOLL_CTL_DEL, fd, 0); 295 epoll_ctl (backend_fd, EPOLL_CTL_DEL, fd, 0);
296 anfds [fd].emask = 0; 296 anfds [fd].emask = 0;
297 iocb->io.aio_reqprio = 0; 297 iocb->io.aio_reqprio = 0;
298 } 298 }
299 299
300 if (iocb->io.aio_buf) 300 if (ecb_expect_false (iocb->io.aio_buf))
301 { 301 {
302 /* iocb active, so cancel it first before resubmit */
303 for (;;)
304 {
305 /* on all relevant kernels, io_cancel fails with EINPROGRESS on "success" */
302 evsys_io_cancel (linuxaio_ctx, &iocb->io, (struct io_event *)0); 306 if (ecb_expect_false (evsys_io_cancel (linuxaio_ctx, &iocb->io, (struct io_event *)0) == 0))
303 /* on relevant kernels, io_cancel fails with EINPROGRES if everything is fine */ 307 break;
308
309 if (ecb_expect_true (errno == EINPROGRESS))
310 break;
311
312 /* the EINPROGRESS test is for nicer error message. clumsy. */
304 assert (("libev: linuxaio unexpected io_cancel failed", errno == EINPROGRESS || errno == EINTR)); 313 assert (("libev: linuxaio unexpected io_cancel failed", errno != EINPROGRESS && errno != EINTR));
305 } 314 }
315 }
316
317 iocb->io.aio_buf =
318 (nev & EV_READ ? POLLIN : 0)
319 | (nev & EV_WRITE ? POLLOUT : 0);
306 320
307 if (nev) 321 if (nev)
308 { 322 {
309 iocb->io.aio_buf =
310 (nev & EV_READ ? POLLIN : 0)
311 | (nev & EV_WRITE ? POLLOUT : 0);
312
313 /* queue iocb up for io_submit */ 323 /* queue iocb up for io_submit */
314 /* this assumes we only ever get one call per fd per loop iteration */ 324 /* this assumes we only ever get one call per fd per loop iteration */
315 ++linuxaio_submitcnt; 325 ++linuxaio_submitcnt;
316 array_needsize (struct iocb *, linuxaio_submits, linuxaio_submitmax, linuxaio_submitcnt, array_needsize_noinit); 326 array_needsize (struct iocb *, linuxaio_submits, linuxaio_submitmax, linuxaio_submitcnt, array_needsize_noinit);
317 linuxaio_submits [linuxaio_submitcnt - 1] = &iocb->io; 327 linuxaio_submits [linuxaio_submitcnt - 1] = &iocb->io;
… …
397int 407int
398linuxaio_ringbuf_valid (EV_P) 408linuxaio_ringbuf_valid (EV_P)
399{ 409{
400 struct aio_ring *ring = (struct aio_ring *)linuxaio_ctx; 410 struct aio_ring *ring = (struct aio_ring *)linuxaio_ctx;
401 411
402 return expect_true (ring->magic == AIO_RING_MAGIC) 412 return ecb_expect_true (ring->magic == AIO_RING_MAGIC)
403 && ring->incompat_features == EV_AIO_RING_INCOMPAT_FEATURES 413 && ring->incompat_features == EV_AIO_RING_INCOMPAT_FEATURES
404 && ring->header_length == sizeof (struct aio_ring); /* TODO: or use it to find io_event[0]? */ 414 && ring->header_length == sizeof (struct aio_ring); /* TODO: or use it to find io_event[0]? */
405} 415}
406 416
407/* read at least one event from kernel, or timeout */ 417/* read at least one event from kernel, or timeout */
… …
412 struct timespec ts; 422 struct timespec ts;
413 struct io_event ioev[8]; /* 256 octet stack space */ 423 struct io_event ioev[8]; /* 256 octet stack space */
414 int want = 1; /* how many events to request */ 424 int want = 1; /* how many events to request */
415 int ringbuf_valid = linuxaio_ringbuf_valid (EV_A); 425 int ringbuf_valid = linuxaio_ringbuf_valid (EV_A);
416 426
417 if (expect_true (ringbuf_valid)) 427 if (ecb_expect_true (ringbuf_valid))
418 { 428 {
419 /* if the ring buffer has any events, we don't wait or call the kernel at all */ 429 /* if the ring buffer has any events, we don't wait or call the kernel at all */
420 if (linuxaio_get_events_from_ring (EV_A)) 430 if (linuxaio_get_events_from_ring (EV_A))
421 return; 431 return;
422 432
… …
452 else if (res) 462 else if (res)
453 { 463 {
454 /* at least one event available, handle them */ 464 /* at least one event available, handle them */
455 linuxaio_parse_events (EV_A_ ioev, res); 465 linuxaio_parse_events (EV_A_ ioev, res);
456 466
457 if (expect_true (ringbuf_valid)) 467 if (ecb_expect_true (ringbuf_valid))
458 { 468 {
459 /* if we have a ring buffer, handle any remaining events in it */ 469 /* if we have a ring buffer, handle any remaining events in it */
460 linuxaio_get_events_from_ring (EV_A); 470 linuxaio_get_events_from_ring (EV_A);
461 471
462 /* at this point, we should have handled all outstanding events */ 472 /* at this point, we should have handled all outstanding events */
… …
493 /* which allows us to pinpoint the erroneous iocb */ 503 /* which allows us to pinpoint the erroneous iocb */
494 for (submitted = 0; submitted < linuxaio_submitcnt; ) 504 for (submitted = 0; submitted < linuxaio_submitcnt; )
495 { 505 {
496 int res = evsys_io_submit (linuxaio_ctx, linuxaio_submitcnt - submitted, linuxaio_submits + submitted); 506 int res = evsys_io_submit (linuxaio_ctx, linuxaio_submitcnt - submitted, linuxaio_submits + submitted);
497 507
498 if (expect_false (res < 0)) 508 if (ecb_expect_false (res < 0))
499 if (errno == EINVAL) 509 if (errno == EINVAL)
500 { 510 {
501 /* This happens for unsupported fds, officially, but in my testing, 511 /* This happens for unsupported fds, officially, but in my testing,
502 * also randomly happens for supported fds. We fall back to good old 512 * also randomly happens for supported fds. We fall back to good old
503 * poll() here, under the assumption that this is a very rare case. 513 * poll() here, under the assumption that this is a very rare case.
… …
553 assert (("libev: event loop rejected bad fd", errno != EBADF)); 563 assert (("libev: event loop rejected bad fd", errno != EBADF));
554 fd_kill (EV_A_ linuxaio_submits [submitted]->aio_fildes); 564 fd_kill (EV_A_ linuxaio_submits [submitted]->aio_fildes);
555 565
556 res = 1; /* skip this iocb */ 566 res = 1; /* skip this iocb */
557 } 567 }
558 else if (errno == EINTR) 568 else if (errno == EINTR) /* not seen in reality, not documented */
559 /* silently ignored */; 569 res = 0; /* silently ignore and retry */
560 else 570 else
561 ev_syserr ("(libev) linuxaio io_submit"); 571 ev_syserr ("(libev) linuxaio io_submit");
562 572
563 submitted += res; 573 submitted += res;
564 } 574 }

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