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Include/linux/timer.h


18419 #ifndef _LINUX_TIMER_H 18420 #define _LINUX_TIMER_H 18421 18422 /* Old-style timers. Please don't use for any new code. 18423 * 18424 * Numbering of these timers should be consecutive to 18425 * minimize processing delays. [MJ] */ 18426 18427 #define BLANK_TIMER 0 /* Console screen-saver */ 18428 #define BEEP_TIMER 1 /* Console beep */ 18429 #define RS_TIMER 2 /* RS-232 ports */ 18430 #define SWAP_TIMER 3 /* Background pageout */ 18431 #define BACKGR_TIMER 4 /* io_request background I/O*/ 18432 #define HD_TIMER 5 /* Old IDE driver */ 18433 #define FLOPPY_TIMER 6 /* Floppy */ 18434 #define QIC02_TAPE_TIMER 7 /* QIC 02 tape */ 18435 #define MCD_TIMER 8 /* Mitsumi CDROM */ 18436 #define GSCD_TIMER 9 /* Goldstar CDROM */ 18437 #define COMTROL_TIMER 10 /* Comtrol serial */ 18438 #define DIGI_TIMER 11 /* Digi serial */ 18439 #define GDTH_TIMER 12 /* Ugh - gdth scsi driver */ 18440 18441 #define COPRO_TIMER 31 /* 387 timeout for buggy 18442 hardware (boot only) */ 18443 18444 struct timer_struct { 18445 unsigned long expires; 18446 void (*fn)(void); 18447 }; 18448 18449 extern unsigned long timer_active; 18450 extern struct timer_struct timer_table[32]; 18451 18452 /* This is completely separate from the above, and is the 18453 * "new and improved" way of handling timers more 18454 * dynamically. Hopefully efficient and general enough 18455 * for most things. 18456 * 18457 * The "hardcoded" timers above are still useful for 18458 * well- defined problems, but the timer-list is probably 18459 * better when you need multiple outstanding timers or 18460 * similar. 18461 * 18462 * The "data" field is in case you want to use the same 18463 * timeout function for several timeouts. You can use 18464 * this to distinguish between the different invocations. 18465 */ 18466 struct timer_list { 18467 struct timer_list *next; /* MUST be first element */ 18468 struct timer_list *prev; 18469 unsigned long expires; 18470 unsigned long data; 18471 void (*function)(unsigned long); 18472 }; 18473 18474 extern void add_timer(struct timer_list * timer); 18475 extern int del_timer(struct timer_list * timer); 18476 18477 /* mod_timer is a more efficient way to update the expire 18478 * field of an active timer (if the timer is inactive it 18479 * will be activated) 18480 * mod_timer(a,b) is equivalent to 18481 * del_timer(a); a->expires = b; add_timer(a) */ 18482 void mod_timer(struct timer_list *timer, 18483 unsigned long expires); 18484 18485 extern void it_real_fn(unsigned long); 18486 18487 extern inline void init_timer(struct timer_list * timer) 18488 { 18489 timer->next = NULL; 18490 timer->prev = NULL; 18491 } 18492 18493 extern inline int 18494 timer_pending(struct timer_list * timer) 18495 { 18496 return timer->prev != NULL; 18497 } 18498 18499 /* These inlines deal with timer wrapping correctly. You 18500 * are strongly encouraged to use them 18501 * 1. Because people otherwise forget 18502 * 2. Because if the timer wrap changes in future 18503 * you wont have to alter your driver code. 18504 * 18505 * Do this with "<0" and ">=0" to only test the sign of 18506 * the result. A good compiler would generate better code 18507 * (and a really good compiler wouldn't care). Gcc is 18508 * currently neither. */ 18509 #define time_after(a,b) ((long)(b) - (long)(a) < 0) 18510 #define time_before(a,b) time_after(b,a) 18511 18512 #define time_after_eq(a,b) ((long)(a) - (long)(b) >= 0) 18513 #define time_before_eq(a,b) time_after_eq(b,a) 18514 18515 #endif



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