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splbio, splclock, splhigh, splimp, splnet, splsoftclock, splsofttty, splstatclock, spltty, splvm, spl0, splx — ????????ͥ???٤?????

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<sys/types.h> <sys/systm.h> intrmask_t splbio(void) intrmask_t splclock(void) intrmask_t splhigh(void) intrmask_t splimp(void) intrmask_t splnet(void) intrmask_t splsoftclock(void) intrmask_t splsofttty(void) intrmask_t splstatclock(void) intrmask_t spltty(void) void spl0(void) void splx(intrmask_t ipl)

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spl() ?ؿ??ե??ߥ??? CPU ?γ???????ͥ???٤? “???٥?” ?????ꤷ?ޤ??? ?????ϥ֥??å????줿ͥ???٥??٥??γ??????ߥϥ??ɥ??μ¹Ԥ????????ޤ??? ???????ߥϥ??ɥ??ˤ??ä?Ĵ?????뤤?Ͻ??????줿?Ǥ??????ǡ????ΰ??? Ĵ?????뤤?Ͻ????????ɥ饤?Ф? “synchronous” ??ʬ(?桼???ץ?????????ɽ???Ƽ¹Ԥ???????ʬ)?ǻ??Ѥ????ޤ???

?̾綠?줾???γ??????ߤ????Ѥ????ɥ饤?Фϡ? config ?ե??????Υ?????ɤˤ??ä? 1 ?Ĥ? ????????ͥ???٥??롼?פ˳??????Ƥ????ޤ??? ?㤨?С?

device foo0 at isa? port 0x0815 irq 12 tty

?ϡ????????? 12 ?? “tty” ͥ???٥??롼?פ˳??????Ƥޤ??? ?????ƥ??ϼ?ưŪ?? xxx ???롼?פγ??????ߤ?ͥ???٤? splxxx () ?ʾ??λ??˸ƤФ????褦?˽??????ޤ???

splx() ?ؿ??ϳ???????ͥ???٥??٥???????Ū?ʿ??ͤ????ꤷ?ޤ??? ???????̤γ??????ߥ??٥??ؿ????֤????ͤ????????????ѿ?????¸???ơ? ???Ǹ???ͥ???٥??٥????᤹?????? splx() ?????Ѥ????????տޤ??Ƥ??ޤ???

spl0() ?ؿ??????Ƥγ??????ߥϥ??ɥ????֥??å????ʤ??ͤ?ͥ???٤򸺾??????ޤ??? ????????AST(??Ʊ???????ƥ??ȥ??å?)?ϥ????ƥब ?桼???⡼?ɤ??????ޤǤδ֤ϥ֥??å??????ޤ???

?????????ʥǥХ????ɥ饤?Фγ???????ͥ???٥??롼?פ?????Ū?ʳ??????Ƥϡ? ?????褽???Τ褦??ʬ???Ǥ??ޤ???

splnet()

?ͥåȥ?????󥿥ե??????ɥ饤?ФΥ??եȥ???????ʬ??

splimp()

???ƤΥͥåȥ?????󥿥ե??????ɥ饤?С?

splbio()

???Ƥ? ?Хåե??????? (?Ĥޤ??ǥ??????ʤ?)?Υɥ饤?С?

spltty()

????Ū?ˤϥͥåȥ???ʳ????̿??ǥХ????Ǥ????? ???¾??ϥͥåȥ???ȥǥ??????ʳ??????ƤΥɥ饤?С?

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splx() ?????? spl0() ?ʳ??????Ƥδؿ??ϡ?????????ͥ???٤??ͤ??֤??ޤ???

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?ʲ??ϡ?ɸ??Ū?ʻ??????Ǥ???

struct foo_softc {
	...
	int flags;
#define	FOO_ASLEEP	1
#define	FOO_READY	2

} foo_softc[NFOO];

int
foowrite(...)
{
	struct foo_softc *sc;
	int s, error;

	...
	s = spltty();
	if (!(sc->flags & FOO_READY)) {
		/* ???????Ǥ??Ƥ??ޤ??????Ե????ʤ????Фʤ??ޤ??? */
		sc->flags |= FOO_ASLEEP;
		error = tsleep(sc, PZERO, "foordy", 0);
		sc->flags &= ~FOO_ASLEEP;
	}
	sc->flags &= ~FOO_READY;
	splx(s);

	...
}

void
foointr(...)
{
	struct foo_softc *sc;

	...
	sc->flags |= FOO_READY;
	if (sc->flags & FOO_ASLEEP)
		/* ï?????桹???ԤäƤ??ޤ??????????Ƥ??????? */
		wakeup(sc);
	...
}

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????????ͥ???٥??٥????????ΥС????????? UNIX ???о줷?ޤ????? ????Ū?ˤ?̾???ǤϤʤ????????Ȥ????Ƥ??ơ????Υ??٥??ޤǤ????Ƥ??ޤ??? (ͥ???? 5 ?ϥ??٥? 5 ?ޤǤ????Ƥ??֥??å????ޤ?)?????????Τ????Ƥ??ޤ??? ?????? FreeBSD ?ˤϤ??ƤϤޤ??ޤ????? ????Ū??̾?? ‘level’ ?Ϥ??ޤ???ʸ?? ‘l’ ?Ȥ??Ƥ??줾???δؿ????ѿ???̾????ȿ?Ǥ????Ƥ??ޤ??? ?????????ºݤˤϤ??Ϥ????٥??ǤϤʤ??? ?ष???ۤʤä?(??ʬŪ?˴ޤޤ줿)?ؿ??????????ƥ??Τ??????֥֥??å??????ޤ??? ????Ū???ֹ??ˤ?????ˡ??ñ???ǽ????̤??? ????????ͥ???٥??٥륰?롼?פǤ????Ȥߤʤ??????Ǥ??ޤ???

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???Υޥ˥奢???ڡ????? Jörg Wunsch ???񤭤ޤ?????