| … | |
… | |
| 488 | |
488 | |
| 489 | These requests are specific to libeio and do not correspond to any OS call. |
489 | These requests are specific to libeio and do not correspond to any OS call. |
| 490 | |
490 | |
| 491 | =over 4 |
491 | =over 4 |
| 492 | |
492 | |
| 493 | =item eio_mtouch (void *addr, size_t length, int flags, int pri, eio_cb cb, void *data) |
493 | =item eio_mtouch (void *addr, size_t length, int flags, int pri, eio_cb cb, void *data) |
| 494 | |
494 | |
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495 | Reads (C<flags == 0>) or modifies (C<flags == EIO_MT_MODIFY) the given |
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496 | memory area, page-wise, that is, it reads (or reads and writes back) the |
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497 | first octet of every page that spans the memory area. |
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498 | |
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499 | This can be used to page in some mmapped file, or dirty some pages. Note |
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500 | that dirtying is an unlocked read-write access, so races can ensue when |
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501 | the some other thread modifies the data stored in that memory area. |
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502 | |
| 495 | =item eio_custom (void (*)(eio_req *) execute, int pri, eio_cb cb, void *data) |
503 | =item eio_custom (void (*)(eio_req *) execute, int pri, eio_cb cb, void *data) |
| 496 | |
504 | |
| 497 | Executes a custom request, i.e., a user-specified callback. |
505 | Executes a custom request, i.e., a user-specified callback. |
| 498 | |
506 | |
| 499 | The callback gets the C<eio_req *> as parameter and is expected to read |
507 | The callback gets the C<eio_req *> as parameter and is expected to read |
| 500 | and modify any request-specific members. Specifically, it should set C<< |
508 | and modify any request-specific members. Specifically, it should set C<< |
| … | |
… | |
| 520 | req->result = open (req->data, O_RDONLY); |
528 | req->result = open (req->data, O_RDONLY); |
| 521 | } |
529 | } |
| 522 | |
530 | |
| 523 | eio_custom (my_open, 0, my_open_done, "/etc/passwd"); |
531 | eio_custom (my_open, 0, my_open_done, "/etc/passwd"); |
| 524 | |
532 | |
| 525 | =item eio_busy (eio_tstamp delay, int pri, eio_cb cb, void *data) |
533 | =item eio_busy (eio_tstamp delay, int pri, eio_cb cb, void *data) |
| 526 | |
534 | |
| 527 | This is a a request that takes C<delay> seconds to execute, but otherwise |
535 | This is a a request that takes C<delay> seconds to execute, but otherwise |
| 528 | does nothing - it simply puts one of the worker threads to sleep for this |
536 | does nothing - it simply puts one of the worker threads to sleep for this |
| 529 | long. |
537 | long. |
| 530 | |
538 | |
| 531 | This request can be used to artificially increase load, e.g. for debugging |
539 | This request can be used to artificially increase load, e.g. for debugging |
| 532 | or benchmarking reasons. |
540 | or benchmarking reasons. |
| 533 | |
541 | |
| 534 | =item eio_nop (int pri, eio_cb cb, void *data) |
542 | =item eio_nop (int pri, eio_cb cb, void *data) |
| 535 | |
543 | |
| 536 | This request does nothing, except go through the whole request cycle. This |
544 | This request does nothing, except go through the whole request cycle. This |
| 537 | can be used to measure latency or in some cases to simplify code, but is |
545 | can be used to measure latency or in some cases to simplify code, but is |
| 538 | not really of much use. |
546 | not really of much use. |
| 539 | |
547 | |
