̾??

timeout, untimeout, callout_handle_init, callout_init, callout_stop, callout_drain, callout_reset, callout_pending, callout_active, callout_deactivate —

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<sys/types.h> <sys/systm.h>

typedef void timeout_t (void *);

struct callout_handle timeout(timeout_t *func, void *arg, int ticks) void callout_handle_init(struct callout_handle *handle)

struct callout_handle handle = CALLOUT_HANDLE_INITIALIZER(&handle)

void untimeout(timeout_t *func, void *arg, struct callout_handle handle) void callout_init(struct callout *c, int mpsafe) int callout_stop(struct callout *c) int callout_drain(struct callout *c) void callout_reset(struct callout *c, int ticks, timeout_t *func, void *arg) int callout_pending(struct callout *c) int callout_active(struct callout *c) callout_deactivate(struct callout *c)

????

?ؿ? timeout() ?? ticks/hz ?ø??˼¹Ԥ????뤿???ΰ??? func ?ˤ??ä?Ϳ?????????ؿ????ƤӽФ??????Υ??????塼?????Ԥ??ޤ??? ???ǤϤʤ??ͤ? ticks ?ϰ??ۤΤ??????? ‘1’ ???Ѵ??????ޤ??? func ?? void * ?ΰ??????????ؿ??ؤΥݥ??󥿤Ǥ????٤??Ǥ??? ?¹Ի??ˤϡ? func ?? arg ?򤽤?ͣ???ΰ????Ȥ??Ƽ????????ޤ??? timeout() ???????????ͤϡ????????塼?뤵?줿 timeout ???????ä??׵??Τ????? untimeout() ?ؿ??Ȥ???³?˻??Ѥ????뤳?Ȥ???ǽ?? struct callout_handle ?Ǥ??? timeout() ?θƤӽФ??ϸŤ??????????ǡ????????????ɤ? callout_*() ?ؿ??????Ѥ????٤??Ǥ???

?ؿ? callout_handle_init() ?ϥϥ??ɥ????????????뤿???˻??Ѥ???untimeout ?ȶ??? ???Ѥ????Ƥ???????̵?????????褦?ˤ??ޤ???

?????륢???ȥϥ??ɥ??? CALLOUT_HANDLE_INITIALIZER() ???ͤ??????Ƥ뤳?Ȥϡ? callout_handle_init() ??Ʊ?ͤε?ǽ???¹Ԥ?????Ū???????ޤ??ϥ??????Х??ʥ????륢???ȥϥ??ɥ??? ???Ѥ??뤿?????󶡤????Ƥ??ޤ???

?ؿ? untimeout() ?ϡ????Υϥ??ɥ?????????????ǧ???뤿???? func ?????? arg ?????????Ѥ??ơ? handle ?˴?Ϣ?դ????줿 timeout ???????ä??ޤ??? ???Υϥ??ɥ뤬???? arg ???????ؿ? func ?????? timeout ?Ȱ??פ??ʤ??????ˤϡ??????Ԥ??ޤ????? handle ?? untimeout() ???Ϥ????????˰????? timeout(), callout_handle_init() ?θƤӽФ????ޤ??? CALLOUT_HANDLE_INITIALIZER(&handle) ???ͤγ????Ƥˤ??äƽ??????????ʤ????Фʤ??ޤ????? ?????˽????????줿?ϥ??ɥ???ȼ?ʤ??ʤ? untimeout ?θƤӽФ??ο????񤤤? ̤?????Ǥ??? untimeout() ?θƤӽФ??ϸŤ??????????ǡ????????????ɤ? callout_*() ?ؿ??????Ѥ????٤??Ǥ???

?ϥ??ɥ뤬?????ƥ??ˤ??äƺ????Ѥ??????Τǡ? ξ???θƤӽФ???Ʊ???ؿ??Υݥ??󥿤????Ӱ????????Ѥ???2 ???ܤθƤӽФ??????? ?ǽ??? timeout ????λ???뤫?????ä??줿?????ˤϡ?1 ?Ĥ? timeout() ?μ¹Ԥ????Υϥ??ɥ뤬?̤? timeout() ?μ¹ԤΥϥ??ɥ뤬???פ??뤳?Ȥ??Ǥ??뤳?Ȥ? (?ճ??ǤϤ??뤬) ??ǽ?Ǥ??? timeout ???????? timeout() ?????? untimeout() ?Τ????? O(1) ?¹Ի??֤??󶡤??ޤ??? timeout (????: ?????? untimeout) ?? Giant ???å????ݻ??????Ƥ??????֤ǡ? softclock() ?????¹Ԥ????ޤ??? ???äơ??????????ݸ???ޤ???

?ؿ? callout_init(), callout_stop(), callout_drain() ?????? callout_reset() ?ϸ?ͭ?Υ????륢???ȹ?¤???????Ƥ뤳?Ȥ???˾???륯?饤?????ȤΤ????Ρ? ?????٥??Υ롼?????Ǥ???

?ؿ? callout_init() ?ϥ????륢???Ȥ??????????????Τ??᤽?Υ????륢???Ȥϲ????????Ѥ??ʤ??? callout_stop(), callout_drain() ?ޤ??? callout_reset() ???Ϥ????뤳?Ȥ??Ǥ??ޤ??? mpsafe ?????? 0 ?ξ????ˤϡ?callout ??¤?Τ? “?ޥ????ץ????å???????” ?Ǥ????ȤϤߤʤ????ޤ????? ???ʤ????????㥤?????ȥ??å????????륢???ȴؿ??θƽФ????? ???????졢?????륢???ȴؿ????????Ȥ??˲??????????褦?ˤ??ޤ???

?ؿ? callout_stop() ?ϡ????Υ????륢???Ȥ???????α???ξ????ˤϡ??????륢???Ȥ??????ä??ޤ??? ?????륢???Ȥ???α???ξ????ˤϡ? callout_stop() ?? 0 ?Ǥʤ??ͤ??֤??ޤ??? ?????륢???Ȥ????ꤵ???Ƥ??ʤ??????˼¹Ԥ????Ƥ??뤫???߼¹????ξ????ˤϡ? 0 ???֤????ޤ??? ???δؿ????ƤӽФ??????Ȥ????????륢???Ȥ? Giant ?ߥ塼?ƥå??? (mutex) ?ˤ??ä??ݸ???Ƥ????????ˤϡ? Giant ???ݻ????Ƥ??ʤ????Фʤ??ޤ?????

?ؿ? callout_drain() ?ϡ??????륢???Ȥ????˿ʹ????ξ????ˤϤ??δ?λ?򥦥????Ȥ??뤳?Ȥ??????ơ? callout_stop() ??Ʊ???Ǥ??? ???δؿ??ϡ????Υ????륢???Ȥ??֥??å????뤫?⤷???ʤ????????????å??? ?ݻ????Ƥ????֤ϡ??褷?ƸƤӽФ????ƤϤʤ??ޤ????? ?????ʤ??ȷ??̤Ȥ??ƥǥåɥ??å????ޤ??? ?????륢???ȥ??֥????ƥब???ˤ??Υ????륢???Ȥ????????Ϥ᤿?ʤ? ?????륢???ȴؿ??? callout_drain() ?μ¹Ԥδ֤˸ƤӽФ????뤫?⤷???ʤ????Ȥ????դ??Ƥ????????? ???????ʤ??顢?????륢???ȥ??֥????ƥ??ϡ? callout_drain() ???֤????˥????륢???Ȥ??????????ߤ????뤳?Ȥ??ݾڤ??ޤ???

?ؿ? callout_reset() ?Ϻǽ??ˤ??Υ????륢???Ȥ??ѻߤ??뤿???? callout_stop() ??Ʊ?ͤΤ??Ȥ??¹Ԥ??????줫?鿷?????????륢???Ȥ? timeout() ??Ʊ??ή???ǳ?Ω???ޤ??? ???δؿ????ƤӽФ??????Ȥ????????륢???Ȥ? Giant ?ߥ塼?ƥå????ˤ??ä??ݸ?????????ˤϡ? Giant ???ݻ??????ʤ????Фʤ??ޤ?????

?ޥ??? callout_pending(), callout_active() ?????? callout_deactivate() ?ϥ????륢???Ȥθ??ߤξ??֤ؤΥ??????????󶡤??ޤ??? ???????Υޥ????򿵽Ť˻??Ѥ????С???Ʊ???????޵????? ??ͭ??¿???ζ??????????򤱤뤳?Ȥ??Ǥ??ޤ??? ?????ʤ??ܺ٤ˤĤ??Ƥϲ????? ?????????????򤹤? ?򻲾Ȥ??Ƥ??????? callout_pending() ?ޥ????ϡ??????륢???Ȥ? ??α?? ?Ǥ??뤫?ɤ????????å????ޤ??? ?????륢???Ȥϥ????ॢ???Ȥ????ꤵ???Ƥ??뤬???֤??ޤ????夷?Ƥ??ʤ????? ??α?? ?Ǥ????ȸ??ʤ????ޤ??? ???ä??󥿥??ॢ???Ȼ??֤????ơ??????륢???ȥ??֥????ƥब???Υ????륢???? ?????????Ϥ????С? callout_pending() ?Ϥ??Ȥ??????륢???ȴؿ????¹Ԥ???λ???? (?ޤ??ϡ??Ϥ???) ???ʤ??Ƥ? FALSE ???֤????Ȥ????դ??Ƥ????????? callout_active() ?ޥ????ϥ????륢???Ȥ? ?????ƥ??? ?Ȥ??ƥޡ????????Ƥ??뤫?ɤ????????å????? callout_deactivate() ?ޥ????ϥ????륢???Ȥ? ?????ƥ??? ?ե饰?򥯥ꥢ???ޤ??? ?????륢???ȥ??֥????ƥ??ϡ??????ॢ???Ȥ????ꤵ???Ƥ??륳???륢???Ȥ? ?????ƥ??? ?????ꤷ?? callout_stop() ?? callout_drain() ?Ǥ? ?????ƥ??? ?򥯥ꥢ???ޤ????? ?????륢???ȴؿ??μ¹Ԥ??̤??? ?̾??ɤ??ꥳ???륢???Ȥδ??¤??ڤ줿?????ˤϡ????ꥢ ???ޤ??? ??

?????????????򤹤?

?????륢???ȥ??֥????ƥ??Ϥ??켫?ΤΥ????ޥ????ƥ????Ȥ??? ?????륢???ȴؿ????ƤӽФ??ޤ??? ????????Ʊ???ʤ??Ǥϡ??????륢???ȴؿ???¾?Υ????åɤ??饳???륢???Ȥ? ???ߤ??ꥻ?åȤ????ߤʤ????¹Ԥ??Ƶ?ư????????ǽ?????????ޤ??? ?äˡ??????륢???ȴؿ???ŵ??Ū?ˤϺǽ???ư???Ȥ??? ?ߥ塼?ƥå??????????????Τǡ? ?????륢???ȴؿ??ϴ??˸ƤӽФ??줿?Ȥ??Ƥ⡢ ?̤Υ????åɤ??????륢???Ȥ??ꥻ?åȤ??뤫?ޤ??????ߤ??褦?Ȥ????ޤ? ???Υߥ塼?ƥå??????Ԥäƥ֥??å??????Ƥ??ޤ??ޤ???

?????륢???ȥ??֥????ƥ??Ϥ???????Ʊ???ط????н褹?뤿???? ¿???Υᥫ?˥??????󶡤??ޤ???

mpsafe ?? FALSE ?????ꤷ?? callout_init() ?????Ѥ??뤳?Ȥǻ??ꤵ????) Giant ?ߥ塼?ƥå????ˤ??äƥ????륢???Ȥ??ݸ?????????ϡ? ???Υߥ塼?ƥå????϶??????????򤱤뤿???˻??ѤǤ??ޤ??? callout_stop() ?? callout_reset() ???ƤӽФ????ˡ? Giant ?ߥ塼?ƥå????ϸƤӽФ?¦?ˤ??äƳ????????ʤ????Фʤ??ޤ??󤬡? ?????륢???Ȥ????ꤷ???Ȥ??????????????ߤ????뤫?ޤ??ϥꥻ?åȤ????? ???Ȥ??ݾڤ????ޤ??? ?????륢???Ȥ????δ?Ϣ?Υߥ塼?ƥå??????˲????????? callout_drain() ?????Ѥ???ɬ?פ??ޤ????뤳?Ȥ????դ??Ƥ?????????
callout_stop() ?????Υ꥿?????ͤϡ??????륢???Ȥ????????줿???ɤ????򼨤??ޤ??? ?????륢???Ȥ????ꤵ?졢 ?????륢???ȴؿ????ޤ??¹Ԥ????Ƥ??ʤ????Ȥ??狼?äƤ????????ϡ? FALSE ???ͤϥ????륢???ȴؿ????ޤ??˸ƤӽФ????褦?Ȥ??Ƥ??뤳?Ȥ򼨤??ޤ??? ?㤨??:
```
if (sc->sc_flags & SCFLG_CALLOUT_RUNNING) {
	if (callout_stop(&sc->sc_callout)) {
		sc->sc_flags &= ~SCFLG_CALLOUT_RUNNING;
		/* successfully stopped */
	} else {
		/*
		 * callout has expired and callout
		 * function is about to be executed
		 */
	}
}
    
```
callout_reset() ???????륢???Ȥ????ߤ??????ɤ??????ꤹ?뤿???? Ʊ???ʥᥫ?˥??ब?ʤˤ??ʤ????Ȥ????դ??Ƥ?????????
callout_pending(), callout_active() ?????? callout_deactivate() ?ޥ????϶????????????򤹤뤿????Ϣ?Ȥ??ƻ??ѤǤ??ޤ??? ?????륢???ȤΥ????ॢ???Ȥ????ꤵ?????Ȥ????????륢???ȥ??֥????ƥ??? ?Ȥ??? ?????ƥ??? ?? ??α?? ??ξ???ǥ????륢???Ȥ??ޡ??????ޤ??? ?????ॢ???Ȼ??֤?ã?????Ȥ????????륢???ȥ??֥????ƥ??? ??α?? ?Υե饰???ǽ??˥??ꥢ???뤳?Ȥˤ??äƥ????륢???Ȥ????????Ϥ??ޤ??? ???ˡ? ?????ƥ??? ?ե饰???Ѥ??ʤ??ǥ????륢???ȴؿ????ƤӽФ??ơ? ?????륢???ȴؿ??????ä????Ǥ??? ?????ƥ??? ?ե饰?򥯥ꥢ???ޤ????? ?????????????줿?ᥫ?˥????Ǥϡ? ?????륢???ȴؿ????Τ? callout_deactivate() ?ޥ????????Ѥ??? ?????ƥ??? ?ե饰?򥯥ꥢ???뤳?Ȥ??׵ᤷ?ޤ??? callout_stop() ?? callout_drain() ?ؿ??????????ˡ? ???? ?????ƥ??? ?? ??α?? ?ե饰??ξ???򥯥ꥢ???ޤ???
callout_pending() ?? TRUE ???֤????硢 ?????륢???ȴؿ??ϡ??ǽ??? ??α?? ?ե饰???????å?????ư???ʤ????????٤??Ǥ??? ?????ϡ??????륢???Ȥ??????륢???ȴؿ????ƤӽФ?????ľ???? callout_reset() ?????Ѥ??ƺƥ??????塼?뤵?줿???Ȥ򼨤??ޤ??? callout_active() ?? FALSE ???֤????硢?????륢???ȴؿ???Ʊ?ͤ?ư???ʤ????֤??٤??Ǥ??? ?????ϡ??????륢???Ȥ????ߤ??줿???Ȥ򼨤??ޤ??? ?Ǹ??ˡ??????륢???ȴؿ??ϡ? ?????ƥ??? ?ե饰?򥯥ꥢ???뤿???? callout_deactivate() ???ƤӽФ??٤??Ǥ??? ?㤨??:
```
mtx_lock(&sc->sc_mtx);
if (callout_pending(&sc->sc_callout)) {
	/* callout was reset */
	mtx_unlock(&sc->sc_mtx);
	return;
}
if (!callout_active(&sc->sc_callout)) {
	/* callout was stopped */
	mtx_unlock(&sc->sc_mtx);
	return;
}
callout_deactivate(&sc->sc_callout);
/* rest of callout function */
    
```
?嵭?ǻ??Ѥ????ߥ塼?ƥå????Τ褦??Ŭ?ڤ?Ʊ?????Ȥ??˻Ȥ????Ȥˤ??ꡢ ???Υ??ץ??????? callout_stop() ?? callout_reset() ?ؿ??????Ĥⶥ???ʤ??ǻ??ѤǤ??ޤ??? ?㤨??:
```
mtx_lock(&sc->sc_mtx);
callout_stop(&sc->sc_callout);
/* The callout is effectively stopped now. */
    
```
?????륢???Ȥ??ޤ???α???Ǥ??????硢???????δؿ????̾??ɤ???ư??ޤ????? ?????륢???Ȥν????????˻ϤޤäƤ??????硢 ?????륢???ȴؿ??ˤ??????ƥ??Ȥˤ????ơ????????δؿ??Ϥ????ʤ? ư???ʤ??????뤳?Ȥˤʤ??ޤ??? ?????륢???ȴؿ???¾?Υ????ɤδ֤?Ʊ???ϡ??????륢???ȴؿ??? callout_deactivate() ?ƤӽФ??򽪤????ޤǥ????륢???Ȥ????ߤ??ꥻ?åȤ??Ԥ????ʤ????Ȥ? ?μ¤ˤ??ޤ???

?????ˡ??嵭?Υƥ??˥å??ϡ? ?????ƥ??? ?ե饰???ºݤ˥????륢???Ȥ?ͭ????̵??????ȿ?Ǥ??뤳?Ȥ??μ¤ˤ??ޤ??? callout_active() ?? FALSE ???֤??????硢???Ȥ??????륢???ȥ??֥????ƥब ?ºݤ˥????륢???ȴؿ??򳫻Ϥ??褦?Ȥ??Ƥ????Ȥ??Ƥ⡢ ?????륢???ȴؿ???ư???ʤ??˽?λ???Ƥ??ޤ??Τǡ? ?¼?Ū??̵?????????Ƥ??ޤ???

?Ǹ??ˡ??????륢???Ȥ????ߤ??褦?Ȥ??Ƥ????Ȥ??? ??θ???ʤ????Фʤ??ʤ??Ǹ??ζ??????郎 1 ?Ĥ????ޤ??? ???ξ??硢?????˲??????뤫?ޤ??Ϻ????Ѥ??줿?ǡ??????֥??????Ȥ? ????????????ɬ?פ????뤫?⤷???ʤ??Τǡ? ?????륢???ȴؿ????Τ? ???ߤ??줿?????륢???Ȥ򸡽Ф??뤵???뤿???˰????Ǥʤ????⤷???ޤ????? ?????륢???Ȥ??????˽?λ???????Ȥ??ݾڤ??뤿???ˤϡ? callout_drain() ?ƤӽФ??????Ѥ??ʤ????Фʤ??ޤ?????

??????

timeout() ?ؿ??? untimeout() ???Ϥ????Ȥ???ǽ?? struct callout_handle ???֤??ޤ??? callout_stop() ?????? callout_drain() ?ؿ??ϸƤӽФ??줿???˥????륢???Ȥ?̤????α???ξ????ˤ? 0 ?ʳ????? ?????Ǥʤ??????ˤ? 0 ???֤??ޤ???

????

???ߤ? timeout ?????? untimeout ?롼?????? Adam M. Costello ?????? George Varghese ?? Redesigning the BSD Callout and Timer Facilities ??̾?դ????줿???ѥ??ݡ??Ȥ?ȯɽ???줿???Ȥ˴??Ť??Ƥ??ޤ??? ?ޤ??? FreeBSD ?ؤ?Ƴ???Τ????? Justin T. Gibbs ?ˤ??äƾ????????????Ƥ??ޤ??? ???μ????ǻ??Ѥ????Ƥ????ǡ?????¤?θ??κ??Ȥϡ? G. Varghese ?????? A. Lauck ?ˤ??ä? Proceedings of the 11th ACM Annual Symposium on Operating Systems Principles ?? Hashed and Hierarchical Timing Wheels: Data Structures for the Efficient Implementation of a Timer Facility ??ȯɽ?????ޤ????? ???ߤμ????ϡ?Ĺ?餯¸?ߤ??Ƥ??????????????Ӻ????? O(n) ?¹Ի??֤? ?󶡤??뤬 untimeout ?????Τ????Υϥ??ɥ????????ޤ????׵ᤷ?ʤ??ä? BSD ???󥯥ꥹ?ȤΥ????륢???ȵ????ˡ????ä??????ޤ?????