diff options
| author | Jacob McDonnell <jacob@jacobmcdonnell.com> | 2026-04-25 16:08:12 -0400 |
|---|---|---|
| committer | Jacob McDonnell <jacob@jacobmcdonnell.com> | 2026-04-25 16:08:12 -0400 |
| commit | b9cde963555b6519c5dbd34a39dee3418f593437 (patch) | |
| tree | 453accad3c3286e3416d4160de4a87223aff684c /static/freebsd/man9/hardclock.9 | |
| parent | 5cb84ec742fd33f78c8022863fadaa8d0d93e176 (diff) | |
feat: Added FreeBSD man pages
Diffstat (limited to 'static/freebsd/man9/hardclock.9')
| -rw-r--r-- | static/freebsd/man9/hardclock.9 | 116 |
1 files changed, 116 insertions, 0 deletions
diff --git a/static/freebsd/man9/hardclock.9 b/static/freebsd/man9/hardclock.9 new file mode 100644 index 00000000..757aed11 --- /dev/null +++ b/static/freebsd/man9/hardclock.9 @@ -0,0 +1,116 @@ +.\" $NetBSD: hardclock.9,v 1.3 2010/03/25 15:17:38 jruoho Exp $ +.\" +.\" Copyright (c) 2001 The NetBSD Foundation, Inc. +.\" All rights reserved. +.\" +.\" This code is derived from software contributed to The NetBSD Foundation +.\" by Thomas Klausner. +.\" +.\" Redistribution and use in source and binary forms, with or without +.\" modification, are permitted provided that the following conditions +.\" are met: +.\" 1. Redistributions of source code must retain the above copyright +.\" notice, this list of conditions and the following disclaimer. +.\" 2. Redistributions in binary form must reproduce the above copyright +.\" notice, this list of conditions and the following disclaimer in the +.\" documentation and/or other materials provided with the distribution. +.\" +.\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS +.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED +.\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR +.\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS +.\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR +.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF +.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS +.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN +.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) +.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE +.\" POSSIBILITY OF SUCH DAMAGE. +.\" +.Dd February 27, 2023 +.Dt HARDCLOCK 9 +.Os +.Sh NAME +.Nm hardclock +.Nd real-time timer +.Sh SYNOPSIS +.Ft void +.Fn hardclock "int cnt" "int usermode" +.Sh DESCRIPTION +The +.Fn hardclock +function is called periodically based on pending work. +The rate ranges from +.Va hz +times per second on a very busy system, to twice a second on an idle system. +The +.Fa cnt +argument reports an estimate of the number of ticks since the last call. +Over long timescales, the average sum of +.Fa cnt +over one second is +.Va hz . +See +.Xr hz 9 +for important details over shorter time scales. +The +.Fa usermode +argument is non-zero when +.Fn hardclock +is called from an context that interrupted usermode execution. +.Pp +.Fn hardclock +may perform different tasks such as: +.Bl -bullet -offset indent +.It +Run the current process's virtual and profile time (decrease the +corresponding timers, if they are activated, and generate +.Li SIGVTALRM +or +.Li SIGPROF , +respectively). +.It +Increment the time-of-day, taking care of any +.Xr ntpd 8 +or +.Xr adjtime 2 +induced changes and leap seconds, as well as any necessary +compensations to keep in sync with PPS signals or external clocks, if +supported by the kernel. +.It +Schedule softclock interrupts +.Po +.Xr swi 9 +.Pc +processing. +.It +Collect +.Xr hwpmc 4 +statistics. +.It +Do device polling, when enabled +.Po +see +.Xr polling 4 +.Pc . +.It +Implement software +.Xr watchdog 9 +processing. +.It +Enqueue +.Xr epoch 9 +processing. +.El +.Sh SEE ALSO +.Xr adjtime 2 , +.Xr ntp_adjtime 2 , +.Xr signal 3 , +.Xr hwpmc 4 , +.Xr polling 4 , +.Xr ntpd 8 , +.Xr epoch 9 , +.Xr eventtimers 9 , +.Xr hz 9 , +.Xr swi 9 , +.Xr watchdog 9 |
