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Comparing libev/ev_iouring.c (file contents):
Revision 1.8 by root, Fri Dec 27 16:08:24 2019 UTC vs.
Revision 1.12 by root, Fri Dec 27 22:16:10 2019 UTC

… …
80 * k) overall, the *API* itself is, I dare to say, not a total trainwreck. 80 * k) overall, the *API* itself is, I dare to say, not a total trainwreck.
81 * the big isuess with it are the bugs requiring epoll, which might 81 * the big isuess with it are the bugs requiring epoll, which might
82 * or might not get fixed (do I hold my breath?). 82 * or might not get fixed (do I hold my breath?).
83 */ 83 */
84 84
85/* TODO: use internal TIMEOUT */
86/* TODO: take advantage of single mmap, NODROP etc. */
87/* TODO: resize cq/sq size independently */
88
85#include <sys/timerfd.h> 89#include <sys/timerfd.h>
86#include <sys/mman.h> 90#include <sys/mman.h>
87#include <poll.h> 91#include <poll.h>
92#include <stdint.h>
88 93
89#define IOURING_INIT_ENTRIES 32 94#define IOURING_INIT_ENTRIES 32
90 95
91/*****************************************************************************/ 96/*****************************************************************************/
92/* syscall wrapdadoop - this section has the raw api/abi definitions */ 97/* syscall wrapdadoop - this section has the raw api/abi definitions */
… …
169 __u32 resv[4]; 174 __u32 resv[4];
170 struct io_sqring_offsets sq_off; 175 struct io_sqring_offsets sq_off;
171 struct io_cqring_offsets cq_off; 176 struct io_cqring_offsets cq_off;
172}; 177};
173 178
179#define IORING_SETUP_CQSIZE 0x00000008
180
174#define IORING_OP_POLL_ADD 6 181#define IORING_OP_POLL_ADD 6
175#define IORING_OP_POLL_REMOVE 7 182#define IORING_OP_POLL_REMOVE 7
183#define IORING_OP_TIMEOUT 11
184#define IORING_OP_TIMEOUT_REMOVE 12
185
186/* relative or absolute, reference clock is CLOCK_MONOTONIC */
187struct iouring_kernel_timespec
188{
189 int64_t tv_sec;
190 long long tv_nsec;
191};
192
193#define IORING_TIMEOUT_ABS 0x00000001
176 194
177#define IORING_ENTER_GETEVENTS 0x01 195#define IORING_ENTER_GETEVENTS 0x01
178 196
179#define IORING_OFF_SQ_RING 0x00000000ULL 197#define IORING_OFF_SQ_RING 0x00000000ULL
180#define IORING_OFF_CQ_RING 0x08000000ULL 198#define IORING_OFF_CQ_RING 0x08000000ULL
181#define IORING_OFF_SQES 0x10000000ULL 199#define IORING_OFF_SQES 0x10000000ULL
182 200
183#define IORING_FEAT_SINGLE_MMAP 0x1 201#define IORING_FEAT_SINGLE_MMAP 0x00000001
184#define IORING_FEAT_NODROP 0x2 202#define IORING_FEAT_NODROP 0x00000002
185#define IORING_FEAT_SUBMIT_STABLE 0x4 203#define IORING_FEAT_SUBMIT_STABLE 0x00000004
186 204
187inline_size 205inline_size
188int 206int
189evsys_io_uring_setup (unsigned entries, struct io_uring_params *params) 207evsys_io_uring_setup (unsigned entries, struct io_uring_params *params)
190{ 208{
… …
285 iouring_tfd = -1; 303 iouring_tfd = -1;
286 iouring_sq_ring = MAP_FAILED; 304 iouring_sq_ring = MAP_FAILED;
287 iouring_cq_ring = MAP_FAILED; 305 iouring_cq_ring = MAP_FAILED;
288 iouring_sqes = MAP_FAILED; 306 iouring_sqes = MAP_FAILED;
289 307
308 if (!have_monotonic) /* cannot really happen, but what if11 */
309 return -1;
310
290 for (;;) 311 for (;;)
291 { 312 {
292 iouring_fd = evsys_io_uring_setup (iouring_entries, &params); 313 iouring_fd = evsys_io_uring_setup (iouring_entries, &params);
293 314
294 if (iouring_fd >= 0) 315 if (iouring_fd >= 0)
295 break; /* yippie */ 316 break; /* yippie */
296 317
297 if (errno != EINVAL) 318 if (errno != EINVAL)
298 return -1; /* we failed */ 319 return -1; /* we failed */
320
321#if TODO
322 if ((~params.features) & (IORING_FEAT_NODROP | IORING_FEATURE_SINGLE_MMAP))
323 return -1; /* we require the above features */
324#endif
299 325
300 /* EINVAL: lots of possible reasons, but maybe 326 /* EINVAL: lots of possible reasons, but maybe
301 * it is because we hit the unqueryable hardcoded size limit 327 * it is because we hit the unqueryable hardcoded size limit
302 */ 328 */
303 329
… …
426 int fd = cqe->user_data & 0xffffffffU; 452 int fd = cqe->user_data & 0xffffffffU;
427 uint32_t gen = cqe->user_data >> 32; 453 uint32_t gen = cqe->user_data >> 32;
428 int res = cqe->res; 454 int res = cqe->res;
429 455
430 /* ignore fd removal events, if there are any. TODO: verify */ 456 /* ignore fd removal events, if there are any. TODO: verify */
457 /* TODO: yes, this triggers */
431 if (cqe->user_data == (__u64)-1) 458 if (cqe->user_data == (__u64)-1)
432 abort ();//D 459 return;
433 460
434 assert (("libev: io_uring fd must be in-bounds", fd >= 0 && fd < anfdmax)); 461 assert (("libev: io_uring fd must be in-bounds", fd >= 0 && fd < anfdmax));
435 462
436 /* documentation lies, of course. the result value is NOT like 463 /* documentation lies, of course. the result value is NOT like
437 * normal syscalls, but like linux raw syscalls, i.e. negative 464 * normal syscalls, but like linux raw syscalls, i.e. negative
… …
444 if (ecb_expect_false (gen != (uint32_t)anfds [fd].egen)) 471 if (ecb_expect_false (gen != (uint32_t)anfds [fd].egen))
445 return; 472 return;
446 473
447 if (ecb_expect_false (res < 0)) 474 if (ecb_expect_false (res < 0))
448 { 475 {
449 //TODO: EINVAL handling (was something failed with this fd) 476 /*TODO: EINVAL handling (was something failed with this fd)*/
450 //TODO: EBUSY happens when? 477 /*TODO: EBUSY happens when?*/
451 478
452 if (res == -EBADF) 479 if (res == -EBADF)
453 { 480 {
454 assert (("libev: event loop rejected bad fd", res != -EBADF)); 481 assert (("libev: event loop rejected bad fd", res != -EBADF));
455 fd_kill (EV_A_ fd); 482 fd_kill (EV_A_ fd);
… …
483iouring_overflow (EV_P) 510iouring_overflow (EV_P)
484{ 511{
485 /* we have two options, resize the queue (by tearing down 512 /* we have two options, resize the queue (by tearing down
486 * everything and recreating it, or living with it 513 * everything and recreating it, or living with it
487 * and polling. 514 * and polling.
488 * we implement this by resizing tghe queue, and, if that fails, 515 * we implement this by resizing the queue, and, if that fails,
489 * we just recreate the state on every failure, which 516 * we just recreate the state on every failure, which
490 * kind of is a very inefficient poll. 517 * kind of is a very inefficient poll.
491 * one danger is, due to the bios toward lower fds, 518 * one danger is, due to the bios toward lower fds,
492 * we will only really get events for those, so 519 * we will only really get events for those, so
493 * maybe we need a poll() fallback, after all. 520 * maybe we need a poll() fallback, after all.
… …
505 else 532 else
506 { 533 {
507 /* we hit the kernel limit, we should fall back to something else. 534 /* we hit the kernel limit, we should fall back to something else.
508 * we can either poll() a few times and hope for the best, 535 * we can either poll() a few times and hope for the best,
509 * poll always, or switch to epoll. 536 * poll always, or switch to epoll.
510 * since we use epoll anyways, go epoll. 537 * TODO: is this necessary with newer kernels?
511 */ 538 */
512 539
513 iouring_internal_destroy (EV_A); 540 iouring_internal_destroy (EV_A);
514 541
515 /* this should make it so that on return, we don'T call any uring functions */ 542 /* this should make it so that on return, we don't call any uring functions */
516 iouring_to_submit = 0; 543 iouring_to_submit = 0;
517 544
518 for (;;) 545 for (;;)
519 { 546 {
520 backend = epoll_init (EV_A_ 0); 547 backend = epoll_init (EV_A_ 0);

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