jimharris 5678725c10 Add rmb() to tsc_read_##x to enforce serialization of rdtsc captures. ... Intel Architecture Manual specifies that rdtsc instruction is not serialized, so without this change, TSC synchronization test would periodically fail, resulting in use of HPET timecounter instead of TSC-low. This caused severe performance degradation (40-50%) when running high IO/s workloads due to HPET MMIO reads and GEOM stat collection. Tests on Xeon E5-2600 (Sandy Bridge) 8C systems were seeing TSC synchronization fail approximately 20% of the time. Sponsored by: Intel Reviewed by: kib MFC after: 3 days		2012-07-24 22:10:11 +00:00
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acpica	- Remove unused code for CR3 and CR4.	2012-06-13 22:53:56 +00:00
bios	Mark all SYSCTL_NODEs static that have no corresponding SYSCTL_DECLs.	2011-11-07 15:43:11 +00:00
cpufreq	Fix apparent logic reversal in setting the 'auto_mode' flag.	2012-02-26 21:24:27 +00:00
include	Add support for the XSAVEOPT instruction use. Our XSAVE/XRSTOR usage	2012-07-14 15:48:30 +00:00
isa	Restore proper use of bounce buffers for ISA DMA. When locking was	2012-03-29 18:58:02 +00:00
pci	Trim stray blank line.	2012-04-11 21:00:33 +00:00
x86	Add rmb() to tsc_read_##x to enforce serialization of rdtsc captures.	2012-07-24 22:10:11 +00:00