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| author | marcel <marcel@FreeBSD.org> | 2011-06-25 16:35:43 +0000 |
|---|---|---|
| committer | marcel <marcel@FreeBSD.org> | 2011-06-25 16:35:43 +0000 |
| commit | 628e425dc7e2da9ca525a72963f7603fc2358863 (patch) | |
| tree | 775deac5fbf6540cd1e441a46d2b7f8b3c7c21ba /sys/ia64 | |
| parent | d717d950fa88ca5ea6d288d7a789bfd1b1709559 (diff) | |
| download | FreeBSD-src-628e425dc7e2da9ca525a72963f7603fc2358863.zip FreeBSD-src-628e425dc7e2da9ca525a72963f7603fc2358863.tar.gz | |
Define the minimum fractional period in terms of hz. We know hz is
a magnitude smaller than itc_freq. A minimum period of 10*hz is
sufficient precision. As a side-effect, the number of clocks per
second, when the machine is idle, dropped by more than 50%.
Be anal and define the maximum period to be at least 4G seconds.
With a 64-bit counter and an ITC frequency that's expected to be
always less than 4Ghz, it takes longer than that to wrap around.
Diffstat (limited to 'sys/ia64')
| -rw-r--r-- | sys/ia64/ia64/clock.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/sys/ia64/ia64/clock.c b/sys/ia64/ia64/clock.c index 881c46f..74b2248 100644 --- a/sys/ia64/ia64/clock.c +++ b/sys/ia64/ia64/clock.c @@ -184,8 +184,8 @@ clock_configure(void *dummy) et->et_quality = 1000; et->et_frequency = itc_freq; et->et_min_period.sec = 0; - et->et_min_period.frac = ((1ul << 32) / itc_freq) << 32; - et->et_max_period.sec = 0xfffffff0 / itc_freq; + et->et_min_period.frac = (0x8000000000000000ul / (u_long)(10*hz)) << 1; + et->et_max_period.sec = ~0ul; /* XXX unless itc_freq >= (1<<32) */ et->et_max_period.frac = ((0xfffffffeul << 32) / itc_freq) << 32; et->et_start = ia64_clock_start; et->et_stop = ia64_clock_stop; |
