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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 1.247 by root, Wed May 21 21:22:10 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#define HPARENT(k) ((((k) - HEAP0 - 1) / DHEAP) + HEAP0)
808
764/* towards the root */ 809/* towards the root */
765void inline_speed 810void inline_speed
766upheap (WT *heap, int k) 811upheap (ANHE *heap, int k)
767{ 812{
768 WT w = heap [k]; 813 ANHE he = heap [k];
769 814
770 for (;;) 815 for (;;)
771 { 816 {
772 int p = k >> 1; 817 int p = HPARENT (k);
773 818
774 /* maybe we could use a dummy element at heap [0]? */ 819 if (p == k || ANHE_at (heap [p]) <= ANHE_at (he))
775 if (!p || heap [p]->at <= w->at)
776 break; 820 break;
777 821
778 heap [k] = heap [p]; 822 heap [k] = heap [p];
779 ev_active (heap [k]) = k; 823 ev_active (ANHE_w (heap [k])) = k;
780 k = p; 824 k = p;
781 } 825 }
782 826
783 heap [k] = w; 827 heap [k] = he;
784 ev_active (heap [k]) = k; 828 ev_active (ANHE_w (he)) = k;
785} 829}
786 830
787/* away from the root */ 831/* away from the root */
788void inline_speed 832void inline_speed
789downheap (WT *heap, int N, int k) 833downheap (ANHE *heap, int N, int k)
790{ 834{
791 WT w = heap [k]; 835 ANHE he = heap [k];
836 ANHE *E = heap + N + HEAP0;
837
838 for (;;)
839 {
840 ev_tstamp minat;
841 ANHE *minpos;
842 ANHE *pos = heap + DHEAP * (k - HEAP0) + HEAP0;
843
844 // find minimum child
845 if (expect_true (pos + DHEAP - 1 < E))
846 {
847 /* fast path */ (minpos = pos + 0), (minat = ANHE_at (*minpos));
848 if ( ANHE_at (pos [1]) < minat) (minpos = pos + 1), (minat = ANHE_at (*minpos));
849 if ( ANHE_at (pos [2]) < minat) (minpos = pos + 2), (minat = ANHE_at (*minpos));
850 if ( ANHE_at (pos [3]) < minat) (minpos = pos + 3), (minat = ANHE_at (*minpos));
851 }
852 else if (pos < E)
853 {
854 /* slow path */ (minpos = pos + 0), (minat = ANHE_at (*minpos));
855 if (pos + 1 < E && ANHE_at (pos [1]) < minat) (minpos = pos + 1), (minat = ANHE_at (*minpos));
856 if (pos + 2 < E && ANHE_at (pos [2]) < minat) (minpos = pos + 2), (minat = ANHE_at (*minpos));
857 if (pos + 3 < E && ANHE_at (pos [3]) < minat) (minpos = pos + 3), (minat = ANHE_at (*minpos));
858 }
859 else
860 break;
861
862 if (ANHE_at (he) <= minat)
863 break;
864
865 heap [k] = *minpos;
866 ev_active (ANHE_w (*minpos)) = k;
867
868 k = minpos - heap;
869 }
870
871 heap [k] = he;
872 ev_active (ANHE_w (he)) = k;
873}
874
875#else // 4HEAP
876
877#define HEAP0 1
878#define HPARENT(k) ((k) >> 1)
879
880/* towards the root */
881void inline_speed
882upheap (ANHE *heap, int k)
883{
884 ANHE he = heap [k];
885
886 for (;;)
887 {
888 int p = HPARENT (k);
889
890 /* maybe we could use a dummy element at heap [0]? */
891 if (!p || ANHE_at (heap [p]) <= ANHE_at (he))
892 break;
893
894 heap [k] = heap [p];
895 ev_active (ANHE_w (heap [k])) = k;
896 k = p;
897 }
898
899 heap [k] = he;
900 ev_active (ANHE_w (heap [k])) = k;
901}
902
903/* away from the root */
904void inline_speed
905downheap (ANHE *heap, int N, int k)
906{
907 ANHE he = heap [k];
792 908
793 for (;;) 909 for (;;)
794 { 910 {
795 int c = k << 1; 911 int c = k << 1;
796 912
797 if (c > N) 913 if (c > N)
798 break; 914 break;
799 915
800 c += c < N && heap [c]->at > heap [c + 1]->at 916 c += c + 1 < N && ANHE_at (heap [c]) > ANHE_at (heap [c + 1])
801 ? 1 : 0; 917 ? 1 : 0;
802 918
803 if (w->at <= heap [c]->at) 919 if (ANHE_at (he) <= ANHE_at (heap [c]))
804 break; 920 break;
805 921
806 heap [k] = heap [c]; 922 heap [k] = heap [c];
807 ev_active (heap [k]) = k; 923 ev_active (ANHE_w (heap [k])) = k;
808 924
809 k = c; 925 k = c;
810 } 926 }
811 927
812 heap [k] = w; 928 heap [k] = he;
813 ev_active (heap [k]) = k; 929 ev_active (ANHE_w (he)) = k;
814} 930}
931#endif
815 932
816void inline_size 933void inline_size
817adjustheap (WT *heap, int N, int k) 934adjustheap (ANHE *heap, int N, int k)
818{ 935{
936 if (k > HEAP0 && ANHE_at (heap [HPARENT (k)]) >= ANHE_at (heap [k]))
819 upheap (heap, k); 937 upheap (heap, k);
938 else
820 downheap (heap, N, k); 939 downheap (heap, N, k);
821} 940}
822 941
823/*****************************************************************************/ 942/*****************************************************************************/
824 943
825typedef struct 944typedef struct
… …
1486#endif 1605#endif
1487 1606
1488void inline_size 1607void inline_size
1489timers_reify (EV_P) 1608timers_reify (EV_P)
1490{ 1609{
1491 while (timercnt && ev_at (timers [1]) <= mn_now) 1610 while (timercnt && ANHE_at (timers [HEAP0]) < mn_now)
1492 { 1611 {
1493 ev_timer *w = (ev_timer *)timers [1]; 1612 ev_timer *w = (ev_timer *)ANHE_w (timers [HEAP0]);
1494 1613
1495 /*assert (("inactive timer on timer heap detected", ev_is_active (w)));*/ 1614 /*assert (("inactive timer on timer heap detected", ev_is_active (w)));*/
1496 1615
1497 /* first reschedule or stop timer */ 1616 /* first reschedule or stop timer */
1498 if (w->repeat) 1617 if (w->repeat)
1499 { 1618 {
1500 assert (("negative ev_timer repeat value found while processing timers", w->repeat > 0.));
1501
1502 ev_at (w) += w->repeat; 1619 ev_at (w) += w->repeat;
1503 if (ev_at (w) < mn_now) 1620 if (ev_at (w) < mn_now)
1504 ev_at (w) = mn_now; 1621 ev_at (w) = mn_now;
1505 1622
1623 assert (("negative ev_timer repeat value found while processing timers", w->repeat > 0.));
1624
1625 ANHE_at_set (timers [HEAP0]);
1506 downheap (timers, timercnt, 1); 1626 downheap (timers, timercnt, HEAP0);
1507 } 1627 }
1508 else 1628 else
1509 ev_timer_stop (EV_A_ w); /* nonrepeating: stop timer */ 1629 ev_timer_stop (EV_A_ w); /* nonrepeating: stop timer */
1510 1630
1511 ev_feed_event (EV_A_ (W)w, EV_TIMEOUT); 1631 ev_feed_event (EV_A_ (W)w, EV_TIMEOUT);
… …
1514 1634
1515#if EV_PERIODIC_ENABLE 1635#if EV_PERIODIC_ENABLE
1516void inline_size 1636void inline_size
1517periodics_reify (EV_P) 1637periodics_reify (EV_P)
1518{ 1638{
1519 while (periodiccnt && ev_at (periodics [1]) <= ev_rt_now) 1639 while (periodiccnt && ANHE_at (periodics [HEAP0]) < ev_rt_now)
1520 { 1640 {
1521 ev_periodic *w = (ev_periodic *)periodics [1]; 1641 ev_periodic *w = (ev_periodic *)ANHE_w (periodics [HEAP0]);
1522 1642
1523 /*assert (("inactive timer on periodic heap detected", ev_is_active (w)));*/ 1643 /*assert (("inactive timer on periodic heap detected", ev_is_active (w)));*/
1524 1644
1525 /* first reschedule or stop timer */ 1645 /* first reschedule or stop timer */
1526 if (w->reschedule_cb) 1646 if (w->reschedule_cb)
1527 { 1647 {
1528 ev_at (w) = w->reschedule_cb (w, ev_rt_now + TIME_EPSILON); 1648 ev_at (w) = w->reschedule_cb (w, ev_rt_now);
1649
1529 assert (("ev_periodic reschedule callback returned time in the past", ev_at (w) > ev_rt_now)); 1650 assert (("ev_periodic reschedule callback returned time in the past", ev_at (w) >= ev_rt_now));
1651
1652 ANHE_at_set (periodics [HEAP0]);
1530 downheap (periodics, periodiccnt, 1); 1653 downheap (periodics, periodiccnt, HEAP0);
1531 } 1654 }
1532 else if (w->interval) 1655 else if (w->interval)
1533 { 1656 {
1534 ev_at (w) = w->offset + ceil ((ev_rt_now - w->offset) / w->interval) * w->interval; 1657 ev_at (w) = w->offset + ceil ((ev_rt_now - w->offset) / w->interval) * w->interval;
1658 /* if next trigger time is not sufficiently in the future, put it there */
1659 /* this might happen because of floating point inexactness */
1535 if (ev_at (w) - ev_rt_now <= TIME_EPSILON) ev_at (w) += w->interval; 1660 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)); 1661 {
1662 ev_at (w) += w->interval;
1663
1664 /* if interval is unreasonably low we might still have a time in the past */
1665 /* so correct this. this will make the periodic very inexact, but the user */
1666 /* has effectively asked to get triggered more often than possible */
1667 if (ev_at (w) < ev_rt_now)
1668 ev_at (w) = ev_rt_now;
1669 }
1670
1671 ANHE_at_set (periodics [HEAP0]);
1537 downheap (periodics, periodiccnt, 1); 1672 downheap (periodics, periodiccnt, HEAP0);
1538 } 1673 }
1539 else 1674 else
1540 ev_periodic_stop (EV_A_ w); /* nonrepeating: stop timer */ 1675 ev_periodic_stop (EV_A_ w); /* nonrepeating: stop timer */
1541 1676
1542 ev_feed_event (EV_A_ (W)w, EV_PERIODIC); 1677 ev_feed_event (EV_A_ (W)w, EV_PERIODIC);
… …
1547periodics_reschedule (EV_P) 1682periodics_reschedule (EV_P)
1548{ 1683{
1549 int i; 1684 int i;
1550 1685
1551 /* adjust periodics after time jump */ 1686 /* adjust periodics after time jump */
1552 for (i = 1; i <= periodiccnt; ++i) 1687 for (i = HEAP0; i < periodiccnt + HEAP0; ++i)
1553 { 1688 {
1554 ev_periodic *w = (ev_periodic *)periodics [i]; 1689 ev_periodic *w = (ev_periodic *)ANHE_w (periodics [i]);
1555 1690
1556 if (w->reschedule_cb) 1691 if (w->reschedule_cb)
1557 ev_at (w) = w->reschedule_cb (w, ev_rt_now); 1692 ev_at (w) = w->reschedule_cb (w, ev_rt_now);
1558 else if (w->interval) 1693 else if (w->interval)
1559 ev_at (w) = w->offset + ceil ((ev_rt_now - w->offset) / w->interval) * w->interval; 1694 ev_at (w) = w->offset + ceil ((ev_rt_now - w->offset) / w->interval) * w->interval;
1560 }
1561 1695
1562 /* now rebuild the heap */ 1696 ANHE_at_set (periodics [i]);
1563 for (i = periodiccnt >> 1; i--; ) 1697 }
1564 downheap (periodics, periodiccnt, i); 1698
1699 /* we don't use floyds algorithm, uphead is simpler and is more cache-efficient */
1700 /* also, this is easy and corretc for both 2-heaps and 4-heaps */
1701 for (i = 0; i < periodiccnt; ++i)
1702 upheap (periodics, i + HEAP0);
1565} 1703}
1566#endif 1704#endif
1567 1705
1568void inline_speed 1706void inline_speed
1569time_update (EV_P_ ev_tstamp max_block) 1707time_update (EV_P_ ev_tstamp max_block)
… …
1623 { 1761 {
1624#if EV_PERIODIC_ENABLE 1762#if EV_PERIODIC_ENABLE
1625 periodics_reschedule (EV_A); 1763 periodics_reschedule (EV_A);
1626#endif 1764#endif
1627 /* adjust timers. this is easy, as the offset is the same for all of them */ 1765 /* adjust timers. this is easy, as the offset is the same for all of them */
1628 for (i = 1; i <= timercnt; ++i) 1766 for (i = 0; i < timercnt; ++i)
1629 ev_at (timers [i]) += ev_rt_now - mn_now; 1767 {
1768 ANHE *he = timers + i + HEAP0;
1769 ANHE_w (*he)->at += ev_rt_now - mn_now;
1770 ANHE_at_set (*he);
1771 }
1630 } 1772 }
1631 1773
1632 mn_now = ev_rt_now; 1774 mn_now = ev_rt_now;
1633 } 1775 }
1634} 1776}
… …
1704 1846
1705 waittime = MAX_BLOCKTIME; 1847 waittime = MAX_BLOCKTIME;
1706 1848
1707 if (timercnt) 1849 if (timercnt)
1708 { 1850 {
1709 ev_tstamp to = ev_at (timers [1]) - mn_now + backend_fudge; 1851 ev_tstamp to = ANHE_at (timers [HEAP0]) - mn_now + backend_fudge;
1710 if (waittime > to) waittime = to; 1852 if (waittime > to) waittime = to;
1711 } 1853 }
1712 1854
1713#if EV_PERIODIC_ENABLE 1855#if EV_PERIODIC_ENABLE
1714 if (periodiccnt) 1856 if (periodiccnt)
1715 { 1857 {
1716 ev_tstamp to = ev_at (periodics [1]) - ev_rt_now + backend_fudge; 1858 ev_tstamp to = ANHE_at (periodics [HEAP0]) - ev_rt_now + backend_fudge;
1717 if (waittime > to) waittime = to; 1859 if (waittime > to) waittime = to;
1718 } 1860 }
1719#endif 1861#endif
1720 1862
1721 if (expect_false (waittime < timeout_blocktime)) 1863 if (expect_false (waittime < timeout_blocktime))
… …
1873{ 2015{
1874 clear_pending (EV_A_ (W)w); 2016 clear_pending (EV_A_ (W)w);
1875 if (expect_false (!ev_is_active (w))) 2017 if (expect_false (!ev_is_active (w)))
1876 return; 2018 return;
1877 2019
1878 assert (("ev_io_start called with illegal fd (must stay constant after start!)", w->fd >= 0 && w->fd < anfdmax)); 2020 assert (("ev_io_stop called with illegal fd (must stay constant after start!)", w->fd >= 0 && w->fd < anfdmax));
1879 2021
1880 wlist_del (&anfds[w->fd].head, (WL)w); 2022 wlist_del (&anfds[w->fd].head, (WL)w);
1881 ev_stop (EV_A_ (W)w); 2023 ev_stop (EV_A_ (W)w);
1882 2024
1883 fd_change (EV_A_ w->fd, 1); 2025 fd_change (EV_A_ w->fd, 1);
… …
1891 2033
1892 ev_at (w) += mn_now; 2034 ev_at (w) += mn_now;
1893 2035
1894 assert (("ev_timer_start called with negative timer repeat value", w->repeat >= 0.)); 2036 assert (("ev_timer_start called with negative timer repeat value", w->repeat >= 0.));
1895 2037
1896 ev_start (EV_A_ (W)w, ++timercnt); 2038 ev_start (EV_A_ (W)w, ++timercnt + HEAP0 - 1);
1897 array_needsize (WT, timers, timermax, timercnt + 1, EMPTY2); 2039 array_needsize (ANHE, timers, timermax, ev_active (w) + 1, EMPTY2);
1898 timers [timercnt] = (WT)w; 2040 ANHE_w (timers [ev_active (w)]) = (WT)w;
2041 ANHE_at_set (timers [ev_active (w)]);
1899 upheap (timers, timercnt); 2042 upheap (timers, ev_active (w));
1900 2043
1901 /*assert (("internal timer heap corruption", timers [ev_active (w)] == w));*/ 2044 /*assert (("internal timer heap corruption", timers [ev_active (w)] == (WT)w));*/
1902} 2045}
1903 2046
1904void noinline 2047void noinline
1905ev_timer_stop (EV_P_ ev_timer *w) 2048ev_timer_stop (EV_P_ ev_timer *w)
1906{ 2049{
… …
1909 return; 2052 return;
1910 2053
1911 { 2054 {
1912 int active = ev_active (w); 2055 int active = ev_active (w);
1913 2056
1914 assert (("internal timer heap corruption", timers [active] == (WT)w)); 2057 assert (("internal timer heap corruption", ANHE_w (timers [active]) == (WT)w));
1915 2058
1916 if (expect_true (active < timercnt)) 2059 if (expect_true (active < timercnt + HEAP0 - 1))
1917 { 2060 {
1918 timers [active] = timers [timercnt]; 2061 timers [active] = timers [timercnt + HEAP0 - 1];
1919 adjustheap (timers, timercnt, active); 2062 adjustheap (timers, timercnt, active);
1920 } 2063 }
1921 2064
1922 --timercnt; 2065 --timercnt;
1923 } 2066 }
… …
1933 if (ev_is_active (w)) 2076 if (ev_is_active (w))
1934 { 2077 {
1935 if (w->repeat) 2078 if (w->repeat)
1936 { 2079 {
1937 ev_at (w) = mn_now + w->repeat; 2080 ev_at (w) = mn_now + w->repeat;
2081 ANHE_at_set (timers [ev_active (w)]);
1938 adjustheap (timers, timercnt, ev_active (w)); 2082 adjustheap (timers, timercnt, ev_active (w));
1939 } 2083 }
1940 else 2084 else
1941 ev_timer_stop (EV_A_ w); 2085 ev_timer_stop (EV_A_ w);
1942 } 2086 }
… …
1963 ev_at (w) = w->offset + ceil ((ev_rt_now - w->offset) / w->interval) * w->interval; 2107 ev_at (w) = w->offset + ceil ((ev_rt_now - w->offset) / w->interval) * w->interval;
1964 } 2108 }
1965 else 2109 else
1966 ev_at (w) = w->offset; 2110 ev_at (w) = w->offset;
1967 2111
1968 ev_start (EV_A_ (W)w, ++periodiccnt); 2112 ev_start (EV_A_ (W)w, ++periodiccnt + HEAP0 - 1);
1969 array_needsize (WT, periodics, periodicmax, periodiccnt + 1, EMPTY2); 2113 array_needsize (ANHE, periodics, periodicmax, ev_active (w) + 1, EMPTY2);
1970 periodics [periodiccnt] = (WT)w; 2114 ANHE_w (periodics [ev_active (w)]) = (WT)w;
1971 upheap (periodics, periodiccnt); 2115 ANHE_at_set (periodics [ev_active (w)]);
2116 upheap (periodics, ev_active (w));
1972 2117
1973 /*assert (("internal periodic heap corruption", periodics [ev_active (w)] == w));*/ 2118 /*assert (("internal periodic heap corruption", ANHE_w (periodics [ev_active (w)]) == (WT)w));*/
1974} 2119}
1975 2120
1976void noinline 2121void noinline
1977ev_periodic_stop (EV_P_ ev_periodic *w) 2122ev_periodic_stop (EV_P_ ev_periodic *w)
1978{ 2123{
… …
1981 return; 2126 return;
1982 2127
1983 { 2128 {
1984 int active = ev_active (w); 2129 int active = ev_active (w);
1985 2130
1986 assert (("internal periodic heap corruption", periodics [active] == (WT)w)); 2131 assert (("internal periodic heap corruption", ANHE_w (periodics [active]) == (WT)w));
1987 2132
1988 if (expect_true (active < periodiccnt)) 2133 if (expect_true (active < periodiccnt + HEAP0 - 1))
1989 { 2134 {
1990 periodics [active] = periodics [periodiccnt]; 2135 periodics [active] = periodics [periodiccnt + HEAP0 - 1];
1991 adjustheap (periodics, periodiccnt, active); 2136 adjustheap (periodics, periodiccnt, active);
1992 } 2137 }
1993 2138
1994 --periodiccnt; 2139 --periodiccnt;
1995 } 2140 }

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