Module Name: src
Committed By: jruoho
Date: Thu Mar 25 14:59:37 UTC 2010
Modified Files:
src/distrib/sets/lists/comp: mi
src/share/man/man9: Makefile hz.9
Log Message:
In addition to 'hz', document also 'tick', 'tickadj', 'stathz', and 'profhz'.
The idea comes from OpenBSD, but this was written largely based on the
comments in kern_clock.c. XXX: schedhz?
To generate a diff of this commit:
cvs rdiff -u -r1.1417 -r1.1418 src/distrib/sets/lists/comp/mi
cvs rdiff -u -r1.322 -r1.323 src/share/man/man9/Makefile
cvs rdiff -u -r1.7 -r1.8 src/share/man/man9/hz.9
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/distrib/sets/lists/comp/mi
diff -u src/distrib/sets/lists/comp/mi:1.1417 src/distrib/sets/lists/comp/mi:1.1418
--- src/distrib/sets/lists/comp/mi:1.1417 Thu Mar 25 10:21:09 2010
+++ src/distrib/sets/lists/comp/mi Thu Mar 25 14:59:36 2010
@@ -1,4 +1,4 @@
-# $NetBSD: mi,v 1.1417 2010/03/25 10:21:09 jruoho Exp $
+# $NetBSD: mi,v 1.1418 2010/03/25 14:59:36 jruoho Exp $
#
# Note: don't delete entries from here - mark them as "obsolete" instead.
#
@@ -9365,6 +9365,7 @@
./usr/share/man/cat9/printf.0 comp-sys-catman .cat
./usr/share/man/cat9/printf_nolog.0 comp-sys-catman .cat
./usr/share/man/cat9/proc_trampoline.0 comp-sys-catman .cat
+./usr/share/man/cat9/profhz.0 comp-sys-catman .cat
./usr/share/man/cat9/prop_array_copyin_ioctl.0 comp-sys-catman .cat
./usr/share/man/cat9/prop_array_copyout_ioctl.0 comp-sys-catman .cat
./usr/share/man/cat9/prop_copy.0 comp-obsolete obsolete
@@ -9511,6 +9512,7 @@
./usr/share/man/cat9/splvm.0 comp-sys-catman .cat
./usr/share/man/cat9/splx.0 comp-sys-catman .cat
./usr/share/man/cat9/sprintf.0 comp-sys-catman .cat
+./usr/share/man/cat9/stathz.0 comp-sys-catman .cat
./usr/share/man/cat9/store.0 comp-sys-catman .cat
./usr/share/man/cat9/subyte.0 comp-sys-catman .cat
./usr/share/man/cat9/suibyte.0 comp-sys-catman .cat
@@ -9567,6 +9569,8 @@
./usr/share/man/cat9/tc_syncbus.0 comp-sys-catman .cat
./usr/share/man/cat9/tc_wmb.0 comp-sys-catman .cat
./usr/share/man/cat9/tcp_congctl.0 comp-sys-catman .cat
+./usr/share/man/cat9/tick.0 comp-sys-catman .cat
+./usr/share/man/cat9/tickadj.0 comp-sys-catman .cat
./usr/share/man/cat9/time.0 comp-obsolete obsolete
./usr/share/man/cat9/time_second.0 comp-sys-catman .cat
./usr/share/man/cat9/time_uptime.0 comp-sys-catman .cat
@@ -15020,6 +15024,7 @@
./usr/share/man/html9/printf.html comp-sys-htmlman html
./usr/share/man/html9/printf_nolog.html comp-sys-htmlman html
./usr/share/man/html9/proc_trampoline.html comp-sys-htmlman html
+./usr/share/man/html9/profhz.html comp-sys-htmlman html
./usr/share/man/html9/prop_array_copyin_ioctl.html comp-sys-htmlman html
./usr/share/man/html9/prop_array_copyout_ioctl.html comp-sys-htmlman html
./usr/share/man/html9/prop_copyin_ioctl.html comp-sys-htmlman html
@@ -15148,6 +15153,7 @@
./usr/share/man/html9/splvm.html comp-sys-htmlman html
./usr/share/man/html9/splx.html comp-sys-htmlman html
./usr/share/man/html9/sprintf.html comp-sys-htmlman html
+./usr/share/man/html9/stathz.html comp-sys-htmlman html
./usr/share/man/html9/store.html comp-sys-htmlman html
./usr/share/man/html9/subyte.html comp-sys-htmlman html
./usr/share/man/html9/suibyte.html comp-sys-htmlman html
@@ -15203,6 +15209,8 @@
./usr/share/man/html9/tc_syncbus.html comp-sys-htmlman html
./usr/share/man/html9/tc_wmb.html comp-sys-htmlman html
./usr/share/man/html9/tcp_congctl.html comp-sys-htmlman html
+./usr/share/man/html9/tick.html comp-sys-htmlman html
+./usr/share/man/html9/tickadj.html comp-sys-htmlman html
./usr/share/man/html9/time_second.html comp-sys-htmlman html
./usr/share/man/html9/time_uptime.html comp-sys-htmlman html
./usr/share/man/html9/timecounter.html comp-sys-htmlman html
@@ -20844,6 +20852,7 @@
./usr/share/man/man9/printf.9 comp-sys-man .man
./usr/share/man/man9/printf_nolog.9 comp-sys-man .man
./usr/share/man/man9/proc_trampoline.9 comp-sys-man .man
+./usr/share/man/man9/profhz.9 comp-sys-man .man
./usr/share/man/man9/prop_array_copyin_ioctl.9 comp-sys-man .man
./usr/share/man/man9/prop_array_copyout_ioctl.9 comp-sys-man .man
./usr/share/man/man9/prop_copy.9 comp-obsolete obsolete
@@ -20990,6 +20999,7 @@
./usr/share/man/man9/splvm.9 comp-sys-man .man
./usr/share/man/man9/splx.9 comp-sys-man .man
./usr/share/man/man9/sprintf.9 comp-sys-man .man
+./usr/share/man/man9/stathz.9 comp-sys-man .man
./usr/share/man/man9/store.9 comp-sys-man .man
./usr/share/man/man9/subyte.9 comp-sys-man .man
./usr/share/man/man9/suibyte.9 comp-sys-man .man
@@ -21046,6 +21056,8 @@
./usr/share/man/man9/tc_syncbus.9 comp-sys-man .man
./usr/share/man/man9/tc_wmb.9 comp-sys-man .man
./usr/share/man/man9/tcp_congctl.9 comp-sys-man .man
+./usr/share/man/man9/tick.9 comp-sys-man .man
+./usr/share/man/man9/tickadj.9 comp-sys-man .man
./usr/share/man/man9/time.9 comp-obsolete obsolete
./usr/share/man/man9/time_second.9 comp-sys-man .man
./usr/share/man/man9/time_uptime.9 comp-sys-man .man
Index: src/share/man/man9/Makefile
diff -u src/share/man/man9/Makefile:1.322 src/share/man/man9/Makefile:1.323
--- src/share/man/man9/Makefile:1.322 Thu Mar 25 10:09:54 2010
+++ src/share/man/man9/Makefile Thu Mar 25 14:59:36 2010
@@ -1,4 +1,4 @@
-# $NetBSD: Makefile,v 1.322 2010/03/25 10:09:54 jruoho Exp $
+# $NetBSD: Makefile,v 1.323 2010/03/25 14:59:36 jruoho Exp $
# Makefile for section 9 (kernel function and variable) manual pages.
@@ -290,6 +290,10 @@
MLINKS+=hash.9 hash32_buf.9 hash.9 hash32_str.9 hash.9 hash32_strn.9
MLINKS+=hashinit.9 hashdone.9
MLINKS+=humanize_number.9 format_bytes.9
+MLINKS+=hz.9 profhz.9 \
+ hz.9 stathz.9 \
+ hz.9 tick.9 \
+ hz.9 tickadj.9
MLINKS+=ieee80211.9 ieee80211_chan2ieee.9 \
ieee80211.9 ieee80211_chan2mode.9 \
ieee80211.9 ieee80211_ieee2mhz.9 \
Index: src/share/man/man9/hz.9
diff -u src/share/man/man9/hz.9:1.7 src/share/man/man9/hz.9:1.8
--- src/share/man/man9/hz.9:1.7 Thu Mar 4 09:57:12 2010
+++ src/share/man/man9/hz.9 Thu Mar 25 14:59:36 2010
@@ -1,4 +1,4 @@
-.\" $NetBSD: hz.9,v 1.7 2010/03/04 09:57:12 jruoho Exp $
+.\" $NetBSD: hz.9,v 1.8 2010/03/25 14:59:36 jruoho Exp $
.\"
.\" Copyright (c) 2001 The NetBSD Foundation, Inc.
.\" All rights reserved.
@@ -27,31 +27,81 @@
.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
.\" POSSIBILITY OF SUCH DAMAGE.
.\"
-.Dd September 4, 2001
+.Dd March 25, 2010
.Dt HZ 9
.Os
.Sh NAME
-.Nm hz
-.Nd system clock frequency
+.Nm hz, tick, tickadj, stathz, profhz
+.Nd system time model
.Sh SYNOPSIS
.In sys/kernel.h
.Pp
-.Va extern int hz;
+.Vt extern int hz;
+.Vt extern int tick;
+.Vt extern int tickadj;
+.Vt extern int stathz;
+.Vt extern int profhz;
+.\" XXX: .Vt extern int schedhz; ?
.Sh DESCRIPTION
-.Nm
+The essential clock handling routines in
+.Nx
+are written to operate with two timers that run independently of each other.
+The main clock, running
+.Va hz
+times per second, is used to keep track of real time.
+.Pp
+In another words,
+.Va hz
specifies the number of times the
.Xr hardclock 9
timer ticks per second.
-.Nm
-is hardware-dependent; it can be overridden (if the machine dependent
-code supports this) by defining
-.Em HZ
+Normally
+.Xr hardclock 9
+increments time by
+.Va tick
+each time it is called.
+If the system clock has drifted,
+.Xr adjtime 2
+may be used to skew this increment based on the rate of
+.Va tickadj .
+.Pp
+The second timer is used to gather timing statistics.
+It also handles kernel and user profiling.
+If the second timer is programmable,
+it is randomized to avoid aliasing between the two clocks.
+The mean frequency of the second timer is
+.Va stathz .
+If a separate clock is not available,
+.Va stathz
+is set to
+.Va hz .
+.Pp
+If profiling is enabled, the clock normally used to drive
+.Va stathz
+may be run at a higher rate
+.Va profhz ,
+which is required to be a multiple of
+.Va stathz .
+This will give higher resolution profiling information.
+.Pp
+These system variables are also available as
+.Em struct clockinfo
+from
+.Xr sysctl 3
+and
+.Sy kern.clockrate
+from
+.Xr sysctl 8 .
+The
+.Va hz
+is hardware-dependent; it can be overridden
+(if the machine dependent code supports this) by defining
+.Dv HZ
in the kernel configuration file (see
.Xr options 4 ) .
-Only override the default value if you really know what you are
-doing.
+Only override the default value if you really know what you are doing.
.Sh SEE ALSO
-.Xr options 4 ,
+.Xr adjtime 2 ,
.Xr callout 9 ,
.Xr hardclock 9 ,
.Xr microtime 9 ,
