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| author | lstewart <lstewart@FreeBSD.org> | 2011-11-19 14:10:16 +0000 |
|---|---|---|
| committer | lstewart <lstewart@FreeBSD.org> | 2011-11-19 14:10:16 +0000 |
| commit | 751092ac03de2a27db50a384379d53f52133c479 (patch) | |
| tree | be0e08688aeafcd4b05ef1e0ffb023edf6699e34 /sys/conf | |
| parent | c3d63592a0ff996956fd6dd88c7b06ba1d08bbca (diff) | |
| download | FreeBSD-src-751092ac03de2a27db50a384379d53f52133c479.zip FreeBSD-src-751092ac03de2a27db50a384379d53f52133c479.tar.gz | |
Core structure and functions to support a feed-forward clock within the kernel.
Implement ffcounter, a monotonically increasing cumulative counter on top of the
active timecounter. Provide low-level functions to read the ffcounter and
convert it to absolute time or a time interval in seconds using the current
ffclock estimates, which track the drift of the oscillator. Add a ring of
fftimehands to track passing of time on each kernel tick and pick up updates of
ffclock estimates.
Committed on behalf of Julien Ridoux and Darryl Veitch from the University of
Melbourne, Australia, as part of the FreeBSD Foundation funded "Feed-Forward
Clock Synchronization Algorithms" project.
For more information, see http://www.synclab.org/radclock/
Submitted by: Julien Ridoux (jridoux at unimelb edu au)
Diffstat (limited to 'sys/conf')
| -rw-r--r-- | sys/conf/NOTES | 8 | ||||
| -rw-r--r-- | sys/conf/options | 1 |
2 files changed, 9 insertions, 0 deletions
diff --git a/sys/conf/NOTES b/sys/conf/NOTES index faf1d25..fa3e374 100644 --- a/sys/conf/NOTES +++ b/sys/conf/NOTES @@ -1186,6 +1186,14 @@ options HZ=100 options PPS_SYNC +# Enable support for generic feed-forward clocks in the kernel. +# The feed-forward clock support is an alternative to the feedback oriented +# ntpd/system clock approach, and is to be used with a feed-forward +# synchronization algorithm such as the RADclock: +# More info here: http://www.synclab.org/radclock + +options FFCLOCK + ##################################################################### # SCSI DEVICES diff --git a/sys/conf/options b/sys/conf/options index 99d64bb..02b908a 100644 --- a/sys/conf/options +++ b/sys/conf/options @@ -80,6 +80,7 @@ COMPRESS_USER_CORES opt_core.h CY_PCI_FASTINTR DEADLKRES opt_watchdog.h DIRECTIO +FFCLOCK FULL_PREEMPTION opt_sched.h IPI_PREEMPTION opt_sched.h GEOM_AES opt_geom.h |
