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Remove the CALLWHEEL_SORT code. It was implemented just for experimenting, 

and I had no plans to ever enable it.  A record of the code is now in the
CVS history of the file, so we can unclutter now.
This commit is contained in:
thorpej 2000-03-23 20:51:09 +00:00
parent 0bb2093748
commit 2b58edac40
1 changed files with 1 additions and 54 deletions
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55
sys/kern/kern_clock.c
View File

@ -1,4 +1,4 @@
/* $NetBSD: kern_clock.c,v 1.52 2000/03/23 06:30:10 thorpej Exp $ */
/* $NetBSD: kern_clock.c,v 1.53 2000/03/23 20:51:09 thorpej Exp $ */
/*-
* Copyright (c) 2000 The NetBSD Foundation, Inc.
@ -338,11 +338,6 @@ volatile struct timeval mono_time;
* the BSD Callout and Timer Facilities", and Justin Gibbs's subsequent
* integration into FreeBSD, modified for NetBSD by Jason R. Thorpe.
*
* This version has been modified to keep the hash chains sorted. Since
* the hash chains are typically short, the overhead of this is minimal.
* Sorted hash chains reduce the number of comparisons in softclock().
* This feature is enabled by defining CALLWHEEL_SORT.
*
* The original work on the data structures used in this implementation
* was published by G. Varghese and A. Lauck in the paper "Hashed and
* Hierarchical Timing Wheels: Data Structures for the Efficient
@ -367,9 +362,6 @@ u_int64_t callwheel_changed; /* # callouts changed */
u_int64_t callwheel_softclocks; /* # times softclock() called */
u_int64_t callwheel_softchecks; /* # checks per softclock() */
u_int64_t callwheel_softempty; /* # empty buckets seen */
#ifdef CALLWHEEL_SORT
u_int64_t callwheel_comparisons; /* # of comparisons on insert */
#endif
#endif /* CALLWHEEL_STATS */
/*
@ -810,9 +802,7 @@ softclock()
void (*func) __P((void *));
void *arg;
int s, idx;
#ifndef CALLWHEEL_SORT
int steps = 0;
#endif
s = splhigh();
softclock_running = 1;
@ -834,25 +824,6 @@ softclock()
#ifdef CALLWHEEL_STATS
callwheel_softchecks++;
#endif
#ifdef CALLWHEEL_SORT
if (c->c_time > hardclock_ticks)
break;
nextsoftcheck = TAILQ_NEXT(c, c_link);
TAILQ_REMOVE(bucket, c, c_link);
#ifdef CALLWHEEL_STATS
callwheel_sizes[idx]--;
callwheel_fired++;
callwheel_count--;
#endif
func = c->c_func;
arg = c->c_arg;
c->c_func = NULL;
c->c_flags &= ~CALLOUT_PENDING;
splx(s);
(*func)(arg);
(void) splhigh();
c = nextsoftcheck;
#else /* CALLWHEEL_SORT */
if (c->c_time != softclock_ticks) {
c = TAILQ_NEXT(c, c_link);
if (++steps >= MAX_SOFTCLOCK_STEPS) {
@ -881,7 +852,6 @@ softclock()
steps = 0;
c = nextsoftcheck;
}
#endif /* CALLWHEEL_SORT */
}
}
nextsoftcheck = NULL;
@ -947,9 +917,6 @@ callout_reset(c, ticks, func, arg)
void *arg;
{
struct callout_queue *bucket;
#ifdef CALLWHEEL_SORT
struct callout *c0;
#endif
int s;
if (ticks <= 0)
@ -981,22 +948,7 @@ callout_reset(c, ticks, func, arg)
callwheel_collisions++;
#endif
#ifdef CALLWHEEL_SORT
for (c0 = TAILQ_FIRST(bucket); c0 != NULL;
c0 = TAILQ_NEXT(c0, c_link)) {
#ifdef CALLWHEEL_STATS
callwheel_comparisons++;
#endif
if (c0->c_time < c->c_time)
continue;
TAILQ_INSERT_BEFORE(c0, c, c_link);
goto out;
}
TAILQ_INSERT_TAIL(bucket, c, c_link);
out:
#else /* CALLWHEEL_SORT */
TAILQ_INSERT_TAIL(bucket, c, c_link);
#endif /* CALLWHEEL_SORT */
#ifdef CALLWHEEL_STATS
callwheel_count++;
@ -1067,12 +1019,7 @@ callout_showstats()
printf("Callwheel statistics:\n");
printf("\tCallouts currently queued: %llu\n", callwheel_count);
#ifdef CALLWHEEL_SORT
printf("\tCallouts established: %llu, Comparisons: %llu\n",
callwheel_established, callwheel_comparisons);
#else
printf("\tCallouts established: %llu\n", callwheel_established);
#endif
printf("\tCallouts disestablished: %llu\n", callwheel_disestablished);
if (callwheel_changed != 0)
printf("\t\tOf those, %llu were changes\n", callwheel_changed);