xref: /csrg-svn/sys/netiso/tp_timer.c (revision 48752)

/***********************************************************
		Copyright IBM Corporation 1987

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ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
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******************************************************************/

/*
 * ARGO Project, Computer Sciences Dept., University of Wisconsin - Madison
 */
/*
 * ARGO TP
 *
 * $Header: tp_timer.c,v 5.2 88/11/18 17:29:07 nhall Exp $
 * $Source: /usr/argo/sys/netiso/RCS/tp_timer.c,v $
 *	@(#)tp_timer.c	7.4 (Berkeley) 04/26/91 *
 *
 * Contains all the timer code.
 * There are two sources of calls to these routines:
 * the clock, and tp.trans. (ok, and tp_pcb.c calls it at init time)
 *
 * Timers come in two flavors - those that generally get
 * cancelled (tp_ctimeout, tp_cuntimeout)
 * and those that either usually expire (tp_etimeout,
 * tp_euntimeout, tp_slowtimo) or may require more than one instance
 * of the timer active at a time.
 *
 * The C timers are stored in the tp_ref structure. Their "going off"
 * is manifested by a driver event of the TM_xxx form.
 *
 * The E timers are handled like the generic kernel callouts.
 * Their "going off" is manifested by a function call w/ 3 arguments.
 */

#ifndef lint
static char *rcsid = "$Header: tp_timer.c,v 5.2 88/11/18 17:29:07 nhall Exp $";
#endif lint

#include "param.h"
#include "types.h"
#include "time.h"
#include "malloc.h"
#include "socket.h"

#include "tp_param.h"
#include "tp_timer.h"
#include "tp_stat.h"
#include "tp_pcb.h"
#include "tp_tpdu.h"
#include "argo_debug.h"
#include "tp_trace.h"
#include "tp_seq.h"

struct	Ecallout *TP_callfree;
struct	Ecallout *TP_callout;
struct	tp_ref *tp_ref;
int		N_TPREF = 100;

extern int tp_maxrefopen;  /* highest ref # of an open tp connection */

/*
 * CALLED FROM:
 *  at autoconfig time from tp_init()
 * 	a combo of event, state, predicate
 * FUNCTION and ARGUMENTS:
 *  initialize data structures for the timers
 */
void
tp_timerinit()
{
	register struct Ecallout *e;
	register int s;
#define GETME(x, t, n) {s = (n)*sizeof(*x); x = (t) malloc(s, M_PCB, M_NOWAIT);\
if (x == 0) panic("tp_timerinit"); bzero((caddr_t)x, s);}
	/*
	 * Initialize storage
	 */
	GETME(TP_callout, struct Ecallout *, 2 * N_TPREF);
	GETME(tp_ref, struct tp_ref *, 1 +  N_TPREF);

	TP_callfree = TP_callout + ((2 * N_TPREF) - 1);
	for (e = TP_callfree; e > TP_callout; e--)
		e->c_next = e - 1;

	/* hate to do this but we really don't want zero to be a legit ref */
	tp_maxrefopen = 1;
	tp_ref[0].tpr_state = REF_FROZEN;  /* white lie -- no ref timer, don't
		* want this one to be allocated- ever
		* unless, of course, you make refs and address instead of an
		* index - then 0 can be allocated
		*/
#undef GETME
}

/**********************  e timers *************************/

/*
 * CALLED FROM:
 *  tp_slowtimo() every 1/2 second, for each open reference
 * FUNCTION and ARGUMENTS:
 *  (refp) indicates a reference structure that is in use.
 *  This ref structure may contain active E-type timers.
 *  Update the timers and if any expire, create an event and
 *  call the driver.
 */
static void
tp_Eclock(refp)
	struct tp_ref	*refp; /* the reference structure */
{
	register struct Ecallout *p1; /* to drift through the list of callouts */
	struct tp_event			 E; /* event to pass to tp_driver() */
	int						 tp_driver(); /* drives the FSM */

	/*
	 * Update real-time timeout queue.
	 * At front of queue are some number of events which are ``due''.
	 * The time to these is <= 0 and if negative represents the
	 * number of ticks which have passed since it was supposed to happen.
	 * The rest of the q elements (times > 0) are events yet to happen,
	 * where the time for each is given as a delta from the previous.
	 * Decrementing just the first of these serves to decrement the time
	 * to all events.
	 *
	 * This version, which calls the driver directly, doesn't pass
	 * along the ticks - may want to add the ticks if there's any use
	 * for them.
	 */
	IncStat(ts_Eticks);
	p1 = refp->tpr_calltodo.c_next;
	while (p1) {
		if (--p1->c_time > 0)
			break;
		if (p1->c_time == 0)
			break;
		p1 = p1->c_next;
	}

	for (;;) {
		struct tp_pcb *tpcb;
		if ((p1 = refp->tpr_calltodo.c_next) == 0 || p1->c_time > 0) {
			break;
		}
		refp->tpr_calltodo.c_next = p1->c_next;
		p1->c_next = TP_callfree;

#ifndef lint
		E.ev_number = p1->c_func;
		E.ATTR(TM_data_retrans).e_low = (SeqNum) p1->c_arg1;
		E.ATTR(TM_data_retrans).e_high = (SeqNum) p1->c_arg2;
		E.ATTR(TM_data_retrans).e_retrans =  p1->c_arg3;
#endif lint
		IFDEBUG(D_TIMER)
			printf("E expired! event 0x%x (0x%x,0x%x), pcb 0x%x ref %d\n",
				p1->c_func, p1->c_arg1, p1->c_arg2, refp->tpr_pcb,
				refp-tp_ref);
		ENDDEBUG

		TP_callfree = p1;
		IncStat(ts_Eexpired);
		(void) tp_driver( tpcb = refp->tpr_pcb, &E);
		if (p1->c_func == TM_reference && tpcb->tp_state == TP_CLOSED)
			free((caddr_t)tpcb, M_PCB); /* XXX wart; where else to do it? */
	}
}

/*
 * CALLED FROM:
 *  tp.trans all over
 * FUNCTION and ARGUMENTS:
 * Set an E type timer.  (refp) is the ref structure.
 * Causes  fun(arg1,arg2,arg3) to be called after time t.
 */
void
tp_etimeout(refp, fun, arg1, arg2, arg3, ticks)
	struct tp_ref	*refp;
	int 			fun; 	/* function to be called */
	u_int			arg1, arg2;
	int				arg3;
	register int	ticks;
{
	register struct Ecallout *p1, *p2, *pnew;
		/* p1 and p2 drift through the list of timeout callout structures,
		 * pnew points to the newly created callout structure
		 */

	IFDEBUG(D_TIMER)
		printf("etimeout pcb 0x%x state 0x%x\n", refp->tpr_pcb,
		refp->tpr_pcb->tp_state);
	ENDDEBUG
	IFTRACE(D_TIMER)
		tptrace(TPPTmisc, "tp_etimeout ref refstate tks Etick", refp-tp_ref,
		refp->tpr_state, ticks, tp_stat.ts_Eticks);
	ENDTRACE

	IncStat(ts_Eset);
	if (ticks == 0)
		ticks = 1;
	pnew = TP_callfree;
	if (pnew == (struct Ecallout *)0)
		panic("tp timeout table overflow");
	TP_callfree = pnew->c_next;
	pnew->c_arg1 = arg1;
	pnew->c_arg2 = arg2;
	pnew->c_arg3 = arg3;
	pnew->c_func = fun;
	for (p1 = &(refp->tpr_calltodo);
							(p2 = p1->c_next) && p2->c_time < ticks; p1 = p2)
		if (p2->c_time > 0)
			ticks -= p2->c_time;
	p1->c_next = pnew;
	pnew->c_next = p2;
	pnew->c_time = ticks;
	if (p2)
		p2->c_time -= ticks;
}

/*
 * CALLED FROM:
 *  tp.trans all over
 * FUNCTION and ARGUMENTS:
 *  Cancel all occurrences of E-timer function (fun) for reference (refp)
 */
void
tp_euntimeout(refp, fun)
	struct tp_ref *refp;
	int			  fun;
{
	register struct Ecallout *p1, *p2; /* ptrs to drift through the list */

	IFTRACE(D_TIMER)
		tptrace(TPPTmisc, "tp_euntimeout ref", refp-tp_ref, 0, 0, 0);
	ENDTRACE

	p1 = &refp->tpr_calltodo;
	while ( (p2 = p1->c_next) != 0) {
		if (p2->c_func == fun)  {
			if (p2->c_next && p2->c_time > 0)
				p2->c_next->c_time += p2->c_time;
			p1->c_next = p2->c_next;
			p2->c_next = TP_callfree;
			TP_callfree = p2;
			IncStat(ts_Ecan_act);
			continue;
		}
		p1 = p2;
	}
}

/*
 * CALLED FROM:
 *  tp.trans, when an incoming ACK causes things to be dropped
 *  from the retransmission queue, and we want their associated
 *  timers to be cancelled.
 * FUNCTION and ARGUMENTS:
 *  cancel all occurrences of function (fun) where (arg2) < (seq)
 */
void
tp_euntimeout_lss(refp, fun, seq)
	struct tp_ref *refp;
	int			  fun;
	SeqNum		  seq;
{
	register struct Ecallout *p1, *p2;

	IFTRACE(D_TIMER)
		tptrace(TPPTmisc, "tp_euntimeoutLSS ref", refp-tp_ref, seq, 0, 0);
	ENDTRACE

	p1 = &refp->tpr_calltodo;
	while ( (p2 = p1->c_next) != 0) {
		if ((p2->c_func == fun) && SEQ_LT(refp->tpr_pcb, p2->c_arg2, seq))  {
			if (p2->c_next && p2->c_time > 0)
				p2->c_next->c_time += p2->c_time;
			p1->c_next = p2->c_next;
			p2->c_next = TP_callfree;
			TP_callfree = p2;
			IncStat(ts_Ecan_act);
			continue;
		}
		p1 = p2;
	}
}

/****************  c timers **********************
 *
 * These are not chained together; they sit
 * in the tp_ref structure. they are the kind that
 * are typically cancelled so it's faster not to
 * mess with the chains
 */

/*
 * CALLED FROM:
 *  the clock, every 500 ms
 * FUNCTION and ARGUMENTS:
 *  Look for open references with active timers.
 *  If they exist, call the appropriate timer routines to update
 *  the timers and possibly generate events.
 *  (The E timers are done in other procedures; the C timers are
 *  updated here, and events for them are generated here.)
 */
ProtoHook
tp_slowtimo()
{
	register int 		r,t;
	struct Ccallout 	*cp;
	struct tp_ref		*rp = tp_ref;
	struct tp_event		E;
	int 				s = splnet();

	/* check only open reference structures */
	IncStat(ts_Cticks);
	rp++;	/* tp_ref[0] is never used */
	for(  r=1 ; (r <= tp_maxrefopen) ; r++,rp++ ) {
		if (rp->tpr_state < REF_OPEN)
			continue;

		/* check the C-type timers */
		cp = rp->tpr_callout;
		for (t=0 ; t < N_CTIMERS; t++,cp++) {
			if( cp->c_active ) {
				if( --cp->c_time <= 0 ) {
					cp->c_active = FALSE;
					E.ev_number = t;
					IFDEBUG(D_TIMER)
						printf("C expired! type 0x%x\n", t);
					ENDDEBUG
					IncStat(ts_Cexpired);
					tp_driver( rp->tpr_pcb, &E);
				}
			}
		}
		/* now update the list */
		tp_Eclock(rp);
	}
	splx(s);
	return 0;
}

/*
 * CALLED FROM:
 *  tp.trans, tp_emit()
 * FUNCTION and ARGUMENTS:
 * 	Set a C type timer of type (which) to go off after (ticks) time.
 */
void
tp_ctimeout(refp, which, ticks)
	register struct tp_ref	*refp;
	int 					which, ticks;
{
	register struct Ccallout *cp = &(refp->tpr_callout[which]);

	IFTRACE(D_TIMER)
		tptrace(TPPTmisc, "tp_ctimeout ref which tpcb active",
			(int)(refp - tp_ref), which, refp->tpr_pcb, cp->c_active);
	ENDTRACE
	if(cp->c_active)
		IncStat(ts_Ccan_act);
	IncStat(ts_Cset);
	cp->c_time = ticks;
	cp->c_active = TRUE;
}

/*
 * CALLED FROM:
 *  tp.trans
 * FUNCTION and ARGUMENTS:
 * 	Version of tp_ctimeout that resets the C-type time if the
 * 	parameter (ticks) is > the current value of the timer.
 */
void
tp_ctimeout_MIN(refp, which, ticks)
	register struct tp_ref	*refp;
	int						which, ticks;
{
	register struct Ccallout *cp = &(refp->tpr_callout[which]);

	IFTRACE(D_TIMER)
		tptrace(TPPTmisc, "tp_ctimeout_MIN ref which tpcb active",
			(int)(refp - tp_ref), which, refp->tpr_pcb, cp->c_active);
	ENDTRACE
	if(cp->c_active)
		IncStat(ts_Ccan_act);
	IncStat(ts_Cset);
	if( cp->c_active )
		cp->c_time = MIN(ticks, cp->c_time);
	else  {
		cp->c_time = ticks;
		cp->c_active = TRUE;
	}
}

/*
 * CALLED FROM:
 *  tp.trans
 * FUNCTION and ARGUMENTS:
 *  Cancel the (which) timer in the ref structure indicated by (refp).
 */
void
tp_cuntimeout(refp, which)
	int						which;
	register struct tp_ref	*refp;
{
	register struct Ccallout *cp;

	cp = &(refp->tpr_callout[which]);

	IFDEBUG(D_TIMER)
		printf("tp_cuntimeout(0x%x, %d) active %d\n", refp, which, cp->c_active);
	ENDDEBUG

	IFTRACE(D_TIMER)
		tptrace(TPPTmisc, "tp_cuntimeout ref which, active", refp-tp_ref,
			which, cp->c_active, 0);
	ENDTRACE

	if(cp->c_active)
		IncStat(ts_Ccan_act);
	else
		IncStat(ts_Ccan_inact);
	cp->c_active = FALSE;
}