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Various minor details:

Browse Source 
Give the HZ/overflow check a 10% margin.
	Eliminate bogus newline.
	If timecounters have equal quality, prefer higher frequency.

Some inspiration from:	bde
This commit is contained in:
Poul-Henning Kamp 2003-11-13 10:03:58 +00:00
parent daf9092bcd
commit 555a5de270
1 changed files with 17 additions and 8 deletions
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25
sys/kern/kern_tc.c
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@ -286,32 +286,41 @@ getmicrotime(struct timeval *tvp)
void
tc_init(struct timecounter *tc)
{
unsigned u;
u_int u;
u = tc->tc_frequency / tc->tc_counter_mask;
/* XXX: We need some margin here, 10% is a guess */
u *= 11;
u /= 10;
if (u > hz && tc->tc_quality >= 0) {
tc->tc_quality = -2000;
if (bootverbose) {
printf("Timecounter \"%s\" frequency %ju Hz",
tc->tc_name, (intmax_t)tc->tc_frequency);
tc->tc_name, (uintmax_t)tc->tc_frequency);
printf(" -- Insufficient hz, needs at least %u\n", u);
}
} else if (tc->tc_quality >= 0 || bootverbose) {
printf("Timecounter \"%s\" frequency %ju Hz quality %d",
tc->tc_name, (intmax_t)tc->tc_frequency,
printf("Timecounter \"%s\" frequency %ju Hz quality %d\n",
tc->tc_name, (uintmax_t)tc->tc_frequency,
tc->tc_quality);
}
printf("\n");
tc->tc_next = timecounters;
timecounters = tc;
(void)tc->tc_get_timecount(tc);
(void)tc->tc_get_timecount(tc);
/* Never automatically use a timecounter with negative quality */
/*
* Never automatically use a timecounter with negative quality.
* Even though we run on the dummy counter, switching here may be
* worse since this timecounter may not be monotonous.
*/
if (tc->tc_quality < 0)
return;
if (tc->tc_quality < timecounter->tc_quality)
return;
if (tc->tc_quality == timecounter->tc_quality &&
tc->tc_frequency < timecounter->tc_frequency)
return;
(void)tc->tc_get_timecount(tc);
(void)tc->tc_get_timecount(tc);
timecounter = tc;
}