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Comparing libev/ev.c (file contents):
Revision 1.234 by root, Tue May 6 23:42:16 2008 UTC vs.
Revision 1.246 by root, Wed May 21 12:51:38 2008 UTC

… …
235# else 235# else
236# define EV_USE_EVENTFD 0 236# define EV_USE_EVENTFD 0
237# endif 237# endif
238#endif 238#endif
239 239
240#ifndef EV_USE_4HEAP
241# define EV_USE_4HEAP !EV_MINIMAL
242#endif
243
244#ifndef EV_HEAP_CACHE_AT
245# define EV_HEAP_CACHE_AT !EV_MINIMAL
246#endif
247
240/* this block fixes any misconfiguration where we know we run into trouble otherwise */ 248/* this block fixes any misconfiguration where we know we run into trouble otherwise */
241 249
242#ifndef CLOCK_MONOTONIC 250#ifndef CLOCK_MONOTONIC
243# undef EV_USE_MONOTONIC 251# undef EV_USE_MONOTONIC
244# define EV_USE_MONOTONIC 0 252# define EV_USE_MONOTONIC 0
… …
422 W w; 430 W w;
423 int events; 431 int events;
424} ANPENDING; 432} ANPENDING;
425 433
426#if EV_USE_INOTIFY 434#if EV_USE_INOTIFY
435/* hash table entry per inotify-id */
427typedef struct 436typedef struct
428{ 437{
429 WL head; 438 WL head;
430} ANFS; 439} ANFS;
440#endif
441
442/* Heap Entry */
443#if EV_HEAP_CACHE_AT
444 typedef struct {
445 ev_tstamp at;
446 WT w;
447 } ANHE;
448
449 #define ANHE_w(he) (he).w /* access watcher, read-write */
450 #define ANHE_at(he) (he).at /* access cached at, read-only */
451 #define ANHE_at_set(he) (he).at = (he).w->at /* update at from watcher */
452#else
453 typedef WT ANHE;
454
455 #define ANHE_w(he) (he)
456 #define ANHE_at(he) (he)->at
457 #define ANHE_at_set(he)
431#endif 458#endif
432 459
433#if EV_MULTIPLICITY 460#if EV_MULTIPLICITY
434 461
435 struct ev_loop 462 struct ev_loop
… …
759 } 786 }
760} 787}
761 788
762/*****************************************************************************/ 789/*****************************************************************************/
763 790
791/*
792 * the heap functions want a real array index. array index 0 uis guaranteed to not
793 * be in-use at any time. the first heap entry is at array [HEAP0]. DHEAP gives
794 * the branching factor of the d-tree.
795 */
796
797/*
798 * at the moment we allow libev the luxury of two heaps,
799 * a small-code-size 2-heap one and a ~1.5kb larger 4-heap
800 * which is more cache-efficient.
801 * the difference is about 5% with 50000+ watchers.
802 */
803#if EV_USE_4HEAP
804
805#define DHEAP 4
806#define HEAP0 (DHEAP - 1) /* index of first element in heap */
807
764/* towards the root */ 808/* towards the root */
765void inline_speed 809void inline_speed
766upheap (WT *heap, int k) 810upheap (ANHE *heap, int k)
767{ 811{
768 WT w = heap [k]; 812 ANHE he = heap [k];
769 813
770 for (;;) 814 for (;;)
771 { 815 {
772 int p = k >> 1; 816 int p = ((k - HEAP0 - 1) / DHEAP) + HEAP0;
773 817
774 /* maybe we could use a dummy element at heap [0]? */ 818 if (p == k || ANHE_at (heap [p]) <= ANHE_at (he))
775 if (!p || heap [p]->at <= w->at)
776 break; 819 break;
777 820
778 heap [k] = heap [p]; 821 heap [k] = heap [p];
779 ev_active (heap [k]) = k; 822 ev_active (ANHE_w (heap [k])) = k;
780 k = p; 823 k = p;
781 } 824 }
782 825
826 ev_active (ANHE_w (he)) = k;
783 heap [k] = w; 827 heap [k] = he;
784 ev_active (heap [k]) = k;
785} 828}
786 829
787/* away from the root */ 830/* away from the root */
788void inline_speed 831void inline_speed
789downheap (WT *heap, int N, int k) 832downheap (ANHE *heap, int N, int k)
790{ 833{
791 WT w = heap [k]; 834 ANHE he = heap [k];
835 ANHE *E = heap + N + HEAP0;
836
837 for (;;)
838 {
839 ev_tstamp minat;
840 ANHE *minpos;
841 ANHE *pos = heap + DHEAP * (k - HEAP0) + HEAP0;
842
843 // find minimum child
844 if (expect_true (pos + DHEAP - 1 < E))
845 {
846 /* fast path */ (minpos = pos + 0), (minat = ANHE_at (*minpos));
847 if ( ANHE_at (pos [1]) < minat) (minpos = pos + 1), (minat = ANHE_at (*minpos));
848 if ( ANHE_at (pos [2]) < minat) (minpos = pos + 2), (minat = ANHE_at (*minpos));
849 if ( ANHE_at (pos [3]) < minat) (minpos = pos + 3), (minat = ANHE_at (*minpos));
850 }
851 else if (pos < E)
852 {
853 /* slow path */ (minpos = pos + 0), (minat = ANHE_at (*minpos));
854 if (pos + 1 < E && ANHE_at (pos [1]) < minat) (minpos = pos + 1), (minat = ANHE_at (*minpos));
855 if (pos + 2 < E && ANHE_at (pos [2]) < minat) (minpos = pos + 2), (minat = ANHE_at (*minpos));
856 if (pos + 3 < E && ANHE_at (pos [3]) < minat) (minpos = pos + 3), (minat = ANHE_at (*minpos));
857 }
858 else
859 break;
860
861 if (ANHE_at (he) <= minat)
862 break;
863
864 ev_active (ANHE_w (*minpos)) = k;
865 heap [k] = *minpos;
866
867 k = minpos - heap;
868 }
869
870 ev_active (ANHE_w (he)) = k;
871 heap [k] = he;
872}
873
874#else // 4HEAP
875
876#define HEAP0 1
877
878/* towards the root */
879void inline_speed
880upheap (ANHE *heap, int k)
881{
882 ANHE he = heap [k];
883
884 for (;;)
885 {
886 int p = k >> 1;
887
888 /* maybe we could use a dummy element at heap [0]? */
889 if (!p || ANHE_at (heap [p]) <= ANHE_at (he))
890 break;
891
892 heap [k] = heap [p];
893 ev_active (ANHE_w (heap [k])) = k;
894 k = p;
895 }
896
897 heap [k] = he;
898 ev_active (ANHE_w (heap [k])) = k;
899}
900
901/* away from the root */
902void inline_speed
903downheap (ANHE *heap, int N, int k)
904{
905 ANHE he = heap [k];
792 906
793 for (;;) 907 for (;;)
794 { 908 {
795 int c = k << 1; 909 int c = k << 1;
796 910
797 if (c > N) 911 if (c > N)
798 break; 912 break;
799 913
800 c += c < N && heap [c]->at > heap [c + 1]->at 914 c += c + 1 < N && ANHE_at (heap [c]) > ANHE_at (heap [c + 1])
801 ? 1 : 0; 915 ? 1 : 0;
802 916
803 if (w->at <= heap [c]->at) 917 if (ANHE_at (he) <= ANHE_at (heap [c]))
804 break; 918 break;
805 919
806 heap [k] = heap [c]; 920 heap [k] = heap [c];
807 ev_active (heap [k]) = k; 921 ev_active (ANHE_w (heap [k])) = k;
808 922
809 k = c; 923 k = c;
810 } 924 }
811 925
812 heap [k] = w; 926 heap [k] = he;
813 ev_active (heap [k]) = k; 927 ev_active (ANHE_w (he)) = k;
814} 928}
929#endif
815 930
816void inline_size 931void inline_size
817adjustheap (WT *heap, int N, int k) 932adjustheap (ANHE *heap, int N, int k)
818{ 933{
819 upheap (heap, k); 934 upheap (heap, k);
820 downheap (heap, N, k); 935 downheap (heap, N, k);
821} 936}
822 937
… …
1486#endif 1601#endif
1487 1602
1488void inline_size 1603void inline_size
1489timers_reify (EV_P) 1604timers_reify (EV_P)
1490{ 1605{
1491 while (timercnt && ev_at (timers [1]) <= mn_now) 1606 while (timercnt && ANHE_at (timers [HEAP0]) < mn_now)
1492 { 1607 {
1493 ev_timer *w = (ev_timer *)timers [1]; 1608 ev_timer *w = (ev_timer *)ANHE_w (timers [HEAP0]);
1494 1609
1495 /*assert (("inactive timer on timer heap detected", ev_is_active (w)));*/ 1610 /*assert (("inactive timer on timer heap detected", ev_is_active (w)));*/
1496 1611
1497 /* first reschedule or stop timer */ 1612 /* first reschedule or stop timer */
1498 if (w->repeat) 1613 if (w->repeat)
1499 { 1614 {
1500 assert (("negative ev_timer repeat value found while processing timers", w->repeat > 0.));
1501
1502 ev_at (w) += w->repeat; 1615 ev_at (w) += w->repeat;
1503 if (ev_at (w) < mn_now) 1616 if (ev_at (w) < mn_now)
1504 ev_at (w) = mn_now; 1617 ev_at (w) = mn_now;
1505 1618
1619 assert (("negative ev_timer repeat value found while processing timers", w->repeat > 0.));
1620
1621 ANHE_at_set (timers [HEAP0]);
1506 downheap (timers, timercnt, 1); 1622 downheap (timers, timercnt, HEAP0);
1507 } 1623 }
1508 else 1624 else
1509 ev_timer_stop (EV_A_ w); /* nonrepeating: stop timer */ 1625 ev_timer_stop (EV_A_ w); /* nonrepeating: stop timer */
1510 1626
1511 ev_feed_event (EV_A_ (W)w, EV_TIMEOUT); 1627 ev_feed_event (EV_A_ (W)w, EV_TIMEOUT);
… …
1514 1630
1515#if EV_PERIODIC_ENABLE 1631#if EV_PERIODIC_ENABLE
1516void inline_size 1632void inline_size
1517periodics_reify (EV_P) 1633periodics_reify (EV_P)
1518{ 1634{
1519 while (periodiccnt && ev_at (periodics [1]) <= ev_rt_now) 1635 while (periodiccnt && ANHE_at (periodics [HEAP0]) < ev_rt_now)
1520 { 1636 {
1521 ev_periodic *w = (ev_periodic *)periodics [1]; 1637 ev_periodic *w = (ev_periodic *)ANHE_w (periodics [HEAP0]);
1522 1638
1523 /*assert (("inactive timer on periodic heap detected", ev_is_active (w)));*/ 1639 /*assert (("inactive timer on periodic heap detected", ev_is_active (w)));*/
1524 1640
1525 /* first reschedule or stop timer */ 1641 /* first reschedule or stop timer */
1526 if (w->reschedule_cb) 1642 if (w->reschedule_cb)
1527 { 1643 {
1528 ev_at (w) = w->reschedule_cb (w, ev_rt_now + TIME_EPSILON); 1644 ev_at (w) = w->reschedule_cb (w, ev_rt_now);
1645
1529 assert (("ev_periodic reschedule callback returned time in the past", ev_at (w) > ev_rt_now)); 1646 assert (("ev_periodic reschedule callback returned time in the past", ev_at (w) >= ev_rt_now));
1647
1648 ANHE_at_set (periodics [HEAP0]);
1530 downheap (periodics, periodiccnt, 1); 1649 downheap (periodics, periodiccnt, HEAP0);
1531 } 1650 }
1532 else if (w->interval) 1651 else if (w->interval)
1533 { 1652 {
1534 ev_at (w) = w->offset + ceil ((ev_rt_now - w->offset) / w->interval) * w->interval; 1653 ev_at (w) = w->offset + ceil ((ev_rt_now - w->offset) / w->interval) * w->interval;
1654 /* if next trigger time is not sufficiently in the future, put it there */
1655 /* this might happen because of floating point inexactness */
1535 if (ev_at (w) - ev_rt_now <= TIME_EPSILON) ev_at (w) += w->interval; 1656 if (ev_at (w) - ev_rt_now < TIME_EPSILON)
1536 assert (("ev_periodic timeout in the past detected while processing timers, negative interval?", ev_at (w) > ev_rt_now)); 1657 {
1658 ev_at (w) += w->interval;
1659
1660 /* if interval is unreasonably low we might still have a time in the past */
1661 /* so correct this. this will make the periodic very inexact, but the user */
1662 /* has effectively asked to get triggered more often than possible */
1663 if (ev_at (w) < ev_rt_now)
1664 ev_at (w) = ev_rt_now;
1665 }
1666
1667 ANHE_at_set (periodics [HEAP0]);
1537 downheap (periodics, periodiccnt, 1); 1668 downheap (periodics, periodiccnt, HEAP0);
1538 } 1669 }
1539 else 1670 else
1540 ev_periodic_stop (EV_A_ w); /* nonrepeating: stop timer */ 1671 ev_periodic_stop (EV_A_ w); /* nonrepeating: stop timer */
1541 1672
1542 ev_feed_event (EV_A_ (W)w, EV_PERIODIC); 1673 ev_feed_event (EV_A_ (W)w, EV_PERIODIC);
… …
1547periodics_reschedule (EV_P) 1678periodics_reschedule (EV_P)
1548{ 1679{
1549 int i; 1680 int i;
1550 1681
1551 /* adjust periodics after time jump */ 1682 /* adjust periodics after time jump */
1552 for (i = 1; i <= periodiccnt; ++i) 1683 for (i = HEAP0; i < periodiccnt + HEAP0; ++i)
1553 { 1684 {
1554 ev_periodic *w = (ev_periodic *)periodics [i]; 1685 ev_periodic *w = (ev_periodic *)ANHE_w (periodics [i]);
1555 1686
1556 if (w->reschedule_cb) 1687 if (w->reschedule_cb)
1557 ev_at (w) = w->reschedule_cb (w, ev_rt_now); 1688 ev_at (w) = w->reschedule_cb (w, ev_rt_now);
1558 else if (w->interval) 1689 else if (w->interval)
1559 ev_at (w) = w->offset + ceil ((ev_rt_now - w->offset) / w->interval) * w->interval; 1690 ev_at (w) = w->offset + ceil ((ev_rt_now - w->offset) / w->interval) * w->interval;
1560 }
1561 1691
1562 /* now rebuild the heap */ 1692 ANHE_at_set (periodics [i]);
1563 for (i = periodiccnt >> 1; i--; ) 1693 }
1564 downheap (periodics, periodiccnt, i); 1694
1695 /* we don't use floyds algorithm, uphead is simpler and is more cache-efficient */
1696 /* also, this is easy and corretc for both 2-heaps and 4-heaps */
1697 for (i = 0; i < periodiccnt; ++i)
1698 upheap (periodics, i + HEAP0);
1565} 1699}
1566#endif 1700#endif
1567 1701
1568void inline_speed 1702void inline_speed
1569time_update (EV_P_ ev_tstamp max_block) 1703time_update (EV_P_ ev_tstamp max_block)
… …
1623 { 1757 {
1624#if EV_PERIODIC_ENABLE 1758#if EV_PERIODIC_ENABLE
1625 periodics_reschedule (EV_A); 1759 periodics_reschedule (EV_A);
1626#endif 1760#endif
1627 /* adjust timers. this is easy, as the offset is the same for all of them */ 1761 /* adjust timers. this is easy, as the offset is the same for all of them */
1628 for (i = 1; i <= timercnt; ++i) 1762 for (i = 0; i < timercnt; ++i)
1629 ev_at (timers [i]) += ev_rt_now - mn_now; 1763 {
1764 ANHE *he = timers + i + HEAP0;
1765 ANHE_w (*he)->at += ev_rt_now - mn_now;
1766 ANHE_at_set (*he);
1767 }
1630 } 1768 }
1631 1769
1632 mn_now = ev_rt_now; 1770 mn_now = ev_rt_now;
1633 } 1771 }
1634} 1772}
… …
1704 1842
1705 waittime = MAX_BLOCKTIME; 1843 waittime = MAX_BLOCKTIME;
1706 1844
1707 if (timercnt) 1845 if (timercnt)
1708 { 1846 {
1709 ev_tstamp to = ev_at (timers [1]) - mn_now + backend_fudge; 1847 ev_tstamp to = ANHE_at (timers [HEAP0]) - mn_now + backend_fudge;
1710 if (waittime > to) waittime = to; 1848 if (waittime > to) waittime = to;
1711 } 1849 }
1712 1850
1713#if EV_PERIODIC_ENABLE 1851#if EV_PERIODIC_ENABLE
1714 if (periodiccnt) 1852 if (periodiccnt)
1715 { 1853 {
1716 ev_tstamp to = ev_at (periodics [1]) - ev_rt_now + backend_fudge; 1854 ev_tstamp to = ANHE_at (periodics [HEAP0]) - ev_rt_now + backend_fudge;
1717 if (waittime > to) waittime = to; 1855 if (waittime > to) waittime = to;
1718 } 1856 }
1719#endif 1857#endif
1720 1858
1721 if (expect_false (waittime < timeout_blocktime)) 1859 if (expect_false (waittime < timeout_blocktime))
… …
1873{ 2011{
1874 clear_pending (EV_A_ (W)w); 2012 clear_pending (EV_A_ (W)w);
1875 if (expect_false (!ev_is_active (w))) 2013 if (expect_false (!ev_is_active (w)))
1876 return; 2014 return;
1877 2015
1878 assert (("ev_io_start called with illegal fd (must stay constant after start!)", w->fd >= 0 && w->fd < anfdmax)); 2016 assert (("ev_io_stop called with illegal fd (must stay constant after start!)", w->fd >= 0 && w->fd < anfdmax));
1879 2017
1880 wlist_del (&anfds[w->fd].head, (WL)w); 2018 wlist_del (&anfds[w->fd].head, (WL)w);
1881 ev_stop (EV_A_ (W)w); 2019 ev_stop (EV_A_ (W)w);
1882 2020
1883 fd_change (EV_A_ w->fd, 1); 2021 fd_change (EV_A_ w->fd, 1);
… …
1891 2029
1892 ev_at (w) += mn_now; 2030 ev_at (w) += mn_now;
1893 2031
1894 assert (("ev_timer_start called with negative timer repeat value", w->repeat >= 0.)); 2032 assert (("ev_timer_start called with negative timer repeat value", w->repeat >= 0.));
1895 2033
1896 ev_start (EV_A_ (W)w, ++timercnt); 2034 ev_start (EV_A_ (W)w, ++timercnt + HEAP0 - 1);
1897 array_needsize (WT, timers, timermax, timercnt + 1, EMPTY2); 2035 array_needsize (ANHE, timers, timermax, ev_active (w) + 1, EMPTY2);
1898 timers [timercnt] = (WT)w; 2036 ANHE_w (timers [ev_active (w)]) = (WT)w;
2037 ANHE_at_set (timers [ev_active (w)]);
1899 upheap (timers, timercnt); 2038 upheap (timers, ev_active (w));
1900 2039
1901 /*assert (("internal timer heap corruption", timers [ev_active (w)] == w));*/ 2040 /*assert (("internal timer heap corruption", timers [ev_active (w)] == (WT)w));*/
1902} 2041}
1903 2042
1904void noinline 2043void noinline
1905ev_timer_stop (EV_P_ ev_timer *w) 2044ev_timer_stop (EV_P_ ev_timer *w)
1906{ 2045{
… …
1909 return; 2048 return;
1910 2049
1911 { 2050 {
1912 int active = ev_active (w); 2051 int active = ev_active (w);
1913 2052
1914 assert (("internal timer heap corruption", timers [active] == (WT)w)); 2053 assert (("internal timer heap corruption", ANHE_w (timers [active]) == (WT)w));
1915 2054
1916 if (expect_true (active < timercnt)) 2055 if (expect_true (active < timercnt + HEAP0 - 1))
1917 { 2056 {
1918 timers [active] = timers [timercnt]; 2057 timers [active] = timers [timercnt + HEAP0 - 1];
1919 adjustheap (timers, timercnt, active); 2058 adjustheap (timers, timercnt, active);
1920 } 2059 }
1921 2060
1922 --timercnt; 2061 --timercnt;
1923 } 2062 }
… …
1933 if (ev_is_active (w)) 2072 if (ev_is_active (w))
1934 { 2073 {
1935 if (w->repeat) 2074 if (w->repeat)
1936 { 2075 {
1937 ev_at (w) = mn_now + w->repeat; 2076 ev_at (w) = mn_now + w->repeat;
2077 ANHE_at_set (timers [ev_active (w)]);
1938 adjustheap (timers, timercnt, ev_active (w)); 2078 adjustheap (timers, timercnt, ev_active (w));
1939 } 2079 }
1940 else 2080 else
1941 ev_timer_stop (EV_A_ w); 2081 ev_timer_stop (EV_A_ w);
1942 } 2082 }
… …
1963 ev_at (w) = w->offset + ceil ((ev_rt_now - w->offset) / w->interval) * w->interval; 2103 ev_at (w) = w->offset + ceil ((ev_rt_now - w->offset) / w->interval) * w->interval;
1964 } 2104 }
1965 else 2105 else
1966 ev_at (w) = w->offset; 2106 ev_at (w) = w->offset;
1967 2107
1968 ev_start (EV_A_ (W)w, ++periodiccnt); 2108 ev_start (EV_A_ (W)w, ++periodiccnt + HEAP0 - 1);
1969 array_needsize (WT, periodics, periodicmax, periodiccnt + 1, EMPTY2); 2109 array_needsize (ANHE, periodics, periodicmax, ev_active (w) + 1, EMPTY2);
1970 periodics [periodiccnt] = (WT)w; 2110 ANHE_w (periodics [ev_active (w)]) = (WT)w;
1971 upheap (periodics, periodiccnt); 2111 ANHE_at_set (periodics [ev_active (w)]);
2112 upheap (periodics, ev_active (w));
1972 2113
1973 /*assert (("internal periodic heap corruption", periodics [ev_active (w)] == w));*/ 2114 /*assert (("internal periodic heap corruption", ANHE_w (periodics [ev_active (w)]) == (WT)w));*/
1974} 2115}
1975 2116
1976void noinline 2117void noinline
1977ev_periodic_stop (EV_P_ ev_periodic *w) 2118ev_periodic_stop (EV_P_ ev_periodic *w)
1978{ 2119{
… …
1981 return; 2122 return;
1982 2123
1983 { 2124 {
1984 int active = ev_active (w); 2125 int active = ev_active (w);
1985 2126
1986 assert (("internal periodic heap corruption", periodics [active] == (WT)w)); 2127 assert (("internal periodic heap corruption", ANHE_w (periodics [active]) == (WT)w));
1987 2128
1988 if (expect_true (active < periodiccnt)) 2129 if (expect_true (active < periodiccnt + HEAP0 - 1))
1989 { 2130 {
1990 periodics [active] = periodics [periodiccnt]; 2131 periodics [active] = periodics [periodiccnt + HEAP0 - 1];
1991 adjustheap (periodics, periodiccnt, active); 2132 adjustheap (periodics, periodiccnt, active);
1992 } 2133 }
1993 2134
1994 --periodiccnt; 2135 --periodiccnt;
1995 } 2136 }

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