[PATCH 1/3]: Replace kernel/timeconst.pl with kernel/timeconst.sh

Rob Landley
2009-01-02T08:13:47Z

From: Rob Landley <rob@landley.net>
Replace kernel/timeconst.pl with kernel/timeconst.sh. The new shell scriptis much simpler, about 1/4 the size, and runs on Red Hat 9 from 2003.
Peter Anvin added this perl to 2.6.25. Before that, the kernel had neverrequired perl to build.
Signed-off-by: Rob Landley <rob@landley.net>---
kernel/Makefile | 4 kernel/timeconst.pl | 378 ------------------------------------------ kernel/timeconst.sh | 91 ++++++++++ 3 files changed, 93 insertions(+), 380 deletions(-)
diff -r d0c7611dcfd6 kernel/Makefile--- a/kernel/Makefile Tue Dec 30 17:48:25 2008 -0800+++ b/kernel/Makefile Fri Jan 02 00:10:44 2009 -0600@@ -115,7 +115,7 @@ $(obj)/time.o: $(obj)/timeconst.h quiet_cmd_timeconst = TIMEC $@- cmd_timeconst = $(PERL) $< $(CONFIG_HZ) > $@+ cmd_timeconst = $(CONFIG_SHELL) $< $(CONFIG_HZ) > $@ targets += timeconst.h-$(obj)/timeconst.h: $(src)/timeconst.pl FORCE+$(obj)/timeconst.h: $(src)/timeconst.sh FORCE $(call if_changed,timeconst)--- /dev/null 1969-12-31 00:00:00.000000000 -0600+++ hg/kernel/timeconst.sh 2009-01-01 23:53:17.000000000 -0600@@ -0,0 +1,91 @@+#!/bin/bash++if [ $# -ne 1 ]+then+ echo "Usage: timeconst.sh HZ"+ exit 1+fi++HZ=$1++# Sanity test: even the shell in Red Hat 9 (circa 2003) supported 64 bit math.++[ $((1<<32)) -lt 0 ] && exit 1++# Output start of header file++cat << EOF+/* Automatically generated by kernel/timeconst.sh */+/* Conversion constants for HZ == $HZ */++#ifndef KERNEL_TIMECONST_H+#define KERNEL_TIMECONST_H++#include <linux/param.h>+#include <linux/types.h>++#if HZ != $HZ+#error "kernel/timeconst.h has the wrong HZ value!"+#endif++EOF++# For both Miliseconds and Microseconds++for i in "MSEC 1000" "USEC 1000000"+do+ NAME=$(echo $i | awk '{print $1}')+ PERIOD=$(echo $i | awk '{print $2}')++ # Find greatest common denominator (using Euclid's algorithm)++ A=$HZ+ B=$PERIOD++ while [ $B -ne 0 ]+ do+ C=$(($A%$B))+ A=$B+ B=$C+ done++ GCD=$A++ # Do this for each direction (HZ_TO_PERIOD and PERIOD_TO_HZ)++ for DIRECTION in 0 1+ do+ if [ $DIRECTION -eq 0 ]+ then+ CONVERT="HZ_TO_${NAME}"+ FROM=$HZ+ TO=$PERIOD+ else+ CONVERT="${NAME}_TO_HZ"+ FROM=$PERIOD+ TO=$HZ+ fi++ # How many shift bits give 32 bits of significant data?++ SHIFT=0+ while [ $(( (($TO<<$SHIFT)+$FROM-1)/$FROM )) -lt $((1<<31)) ]+ do+ SHIFT=$(( $SHIFT+1 ))+ done++ MUL32=$(( (($TO<<$SHIFT)+$FROM-1)/$FROM ))+ MUL32=$(printf %x $MUL32)+ echo "#define ${CONVERT}_MUL32 U64_C(0x$MUL32)"+ ADJ32=$(($FROM/$GCD))+ ADJ32=$(( (($ADJ32-1)<<$SHIFT)/$ADJ32 ))+ ADJ32=$(printf %x $ADJ32)+ echo "#define ${CONVERT}_ADJ32 U64_C(0x$ADJ32)"+ echo "#define ${CONVERT}_SHR32 $SHIFT"+ echo "#define ${CONVERT}_NUM U64_C($(($TO/$GCD)))"+ echo "#define ${CONVERT}_DEN U64_C($(($FROM/$GCD)))"+ done+done++echo+echo "#endif /* KERNEL_TIMECHONST_H */"--- hg/kernel/timeconst.pl 2008-11-22 19:09:13.000000000 -0600+++ /dev/null 1969-12-31 00:00:00.000000000 -0600@@ -1,378 +0,0 @@-#!/usr/bin/perl-# ------------------------------------------------------------------------#-# Copyright 2007-2008 rPath, Inc. - All Rights Reserved-#-# This file is part of the Linux kernel, and is made available under-# the terms of the GNU General Public License version 2 or (at your-# option) any later version; incorporated herein by reference.-#-# ------------------------------------------------------------------------#--#-# Usage: timeconst.pl HZ > timeconst.h-#--# Precomputed values for systems without Math::BigInt-# Generated by:-# timeconst.pl --can 24 32 48 64 100 122 128 200 250 256 300 512 1000 1024 1200-%canned_values = (- 24 => [- '0xa6aaaaab','0x2aaaaaa',26,- 125,3,- '0xc49ba5e4','0x1fbe76c8b4',37,- 3,125,- '0xa2c2aaab','0xaaaa',16,- 125000,3,- '0xc9539b89','0x7fffbce4217d',47,- 3,125000,- ], 32 => [- '0xfa000000','0x6000000',27,- 125,4,- '0x83126e98','0xfdf3b645a',36,- 4,125,- '0xf4240000','0x0',17,- 31250,1,- '0x8637bd06','0x3fff79c842fa',46,- 1,31250,- ], 48 => [- '0xa6aaaaab','0x6aaaaaa',27,- 125,6,- '0xc49ba5e4','0xfdf3b645a',36,- 6,125,- '0xa2c2aaab','0x15555',17,- 62500,3,- '0xc9539b89','0x3fffbce4217d',46,- 3,62500,- ], 64 => [- '0xfa000000','0xe000000',28,- 125,8,- '0x83126e98','0x7ef9db22d',35,- 8,125,- '0xf4240000','0x0',18,- 15625,1,- '0x8637bd06','0x1fff79c842fa',45,- 1,15625,- ], 100 => [- '0xa0000000','0x0',28,- 10,1,- '0xcccccccd','0x733333333',35,- 1,10,- '0x9c400000','0x0',18,- 10000,1,- '0xd1b71759','0x1fff2e48e8a7',45,- 1,10000,- ], 122 => [- '0x8325c53f','0xfbcda3a',28,- 500,61,- '0xf9db22d1','0x7fbe76c8b',35,- 61,500,- '0x8012e2a0','0x3ef36',18,- 500000,61,- '0xffda4053','0x1ffffbce4217',45,- 61,500000,- ], 128 => [- '0xfa000000','0x1e000000',29,- 125,16,- '0x83126e98','0x3f7ced916',34,- 16,125,- '0xf4240000','0x40000',19,- 15625,2,- '0x8637bd06','0xfffbce4217d',44,- 2,15625,- ], 200 => [- '0xa0000000','0x0',29,- 5,1,- '0xcccccccd','0x333333333',34,- 1,5,- '0x9c400000','0x0',19,- 5000,1,- '0xd1b71759','0xfff2e48e8a7',44,- 1,5000,- ], 250 => [- '0x80000000','0x0',29,- 4,1,- '0x80000000','0x180000000',33,- 1,4,- '0xfa000000','0x0',20,- 4000,1,- '0x83126e98','0x7ff7ced9168',43,- 1,4000,- ], 256 => [- '0xfa000000','0x3e000000',30,- 125,32,- '0x83126e98','0x1fbe76c8b',33,- 32,125,- '0xf4240000','0xc0000',20,- 15625,4,- '0x8637bd06','0x7ffde7210be',43,- 4,15625,- ], 300 => [- '0xd5555556','0x2aaaaaaa',30,- 10,3,- '0x9999999a','0x1cccccccc',33,- 3,10,- '0xd0555556','0xaaaaa',20,- 10000,3,- '0x9d495183','0x7ffcb923a29',43,- 3,10000,- ], 512 => [- '0xfa000000','0x7e000000',31,- 125,64,- '0x83126e98','0xfdf3b645',32,- 64,125,- '0xf4240000','0x1c0000',21,- 15625,8,- '0x8637bd06','0x3ffef39085f',42,- 8,15625,- ], 1000 => [- '0x80000000','0x0',31,- 1,1,- '0x80000000','0x0',31,- 1,1,- '0xfa000000','0x0',22,- 1000,1,- '0x83126e98','0x1ff7ced9168',41,- 1,1000,- ], 1024 => [- '0xfa000000','0xfe000000',32,- 125,128,- '0x83126e98','0x7ef9db22',31,- 128,125,- '0xf4240000','0x3c0000',22,- 15625,16,- '0x8637bd06','0x1fff79c842f',41,- 16,15625,- ], 1200 => [- '0xd5555556','0xd5555555',32,- 5,6,- '0x9999999a','0x66666666',31,- 6,5,- '0xd0555556','0x2aaaaa',22,- 2500,3,- '0x9d495183','0x1ffcb923a29',41,- 3,2500,- ]-);--$has_bigint = eval 'use Math::BigInt qw(bgcd); 1;';--sub bint($)-{- my($x) = @_;- return Math::BigInt->new($x);-}--#-# Constants for division by reciprocal multiplication.-# (bits, numerator, denominator)-#-sub fmul($$$)-{- my ($b,$n,$d) = @_;-- $n = bint($n);- $d = bint($d);-- return scalar (($n << $b)+$d-bint(1))/$d;-}--sub fadj($$$)-{- my($b,$n,$d) = @_;-- $n = bint($n);- $d = bint($d);-- $d = $d/bgcd($n, $d);- return scalar (($d-bint(1)) << $b)/$d;-}--sub fmuls($$$) {- my($b,$n,$d) = @_;- my($s,$m);- my($thres) = bint(1) << ($b-1);-- $n = bint($n);- $d = bint($d);-- for ($s = 0; 1; $s++) {- $m = fmul($s,$n,$d);- return $s if ($m >= $thres);- }- return 0;-}--# Generate a hex value if the result fits in 64 bits;-# otherwise skip.-sub bignum_hex($) {- my($x) = @_;- my $s = $x->as_hex();-- return (length($s) > 18) ? undef : $s;-}--# Provides mul, adj, and shr factors for a specific-# (bit, time, hz) combination-sub muladj($$$) {- my($b, $t, $hz) = @_;- my $s = fmuls($b, $t, $hz);- my $m = fmul($s, $t, $hz);- my $a = fadj($s, $t, $hz);- return (bignum_hex($m), bignum_hex($a), $s);-}--# Provides numerator, denominator values-sub numden($$) {- my($n, $d) = @_;- my $g = bgcd($n, $d);- return ($n/$g, $d/$g);-}--# All values for a specific (time, hz) combo-sub conversions($$) {- my ($t, $hz) = @_;- my @val = ();-- # HZ_TO_xx- push(@val, muladj(32, $t, $hz));- push(@val, numden($t, $hz));-- # xx_TO_HZ- push(@val, muladj(32, $hz, $t));- push(@val, numden($hz, $t));-- return @val;-}--sub compute_values($) {- my($hz) = @_;- my @val = ();- my $s, $m, $a, $g;-- if (!$has_bigint) {- die "$0: HZ == $hz not canned and ".- "Math::BigInt not available\n";- }-- # MSEC conversions- push(@val, conversions(1000, $hz));-- # USEC conversions- push(@val, conversions(1000000, $hz));-- return @val;-}--sub outputval($$)-{- my($name, $val) = @_;- my $csuf;-- if (defined($val)) {- if ($name !~ /SHR/) {- $val = "U64_C($val)";- }- printf "#define %-23s %s\n", $name.$csuf, $val.$csuf;- }-}--sub output($@)-{- my($hz, @val) = @_;- my $pfx, $bit, $suf, $s, $m, $a;-- print "/* Automatically generated by kernel/timeconst.pl */\n";- print "/* Conversion constants for HZ == $hz */\n";- print "\n";- print "#ifndef KERNEL_TIMECONST_H\n";- print "#define KERNEL_TIMECONST_H\n";- print "\n";-- print "#include <linux/param.h>\n";- print "#include <linux/types.h>\n";-- print "\n";- print "#if HZ != $hz\n";- print "#error \"kernel/timeconst.h has the wrong HZ value!\"\n";- print "#endif\n";- print "\n";-- foreach $pfx ('HZ_TO_MSEC','MSEC_TO_HZ',- 'HZ_TO_USEC','USEC_TO_HZ') {- foreach $bit (32) {- foreach $suf ('MUL', 'ADJ', 'SHR') {- outputval("${pfx}_$suf$bit", shift(@val));- }- }- foreach $suf ('NUM', 'DEN') {- outputval("${pfx}_$suf", shift(@val));- }- }-- print "\n";- print "#endif /* KERNEL_TIMECONST_H */\n";-}--# Pretty-print Perl values-sub perlvals(@) {- my $v;- my @l = ();-- foreach $v (@_) {- if (!defined($v)) {- push(@l, 'undef');- } elsif ($v =~ /^0x/) {- push(@l, "\'".$v."\'");- } else {- push(@l, $v.'');- }- }- return join(',', @l);-}--($hz) = @ARGV;--# Use this to generate the %canned_values structure-if ($hz eq '--can') {- shift(@ARGV);- @hzlist = sort {$a <=> $b} (@ARGV);-- print "# Precomputed values for systems without Math::BigInt\n";- print "# Generated by:\n";- print "# timeconst.pl --can ", join(' ', @hzlist), "\n";- print "\%canned_values = (\n";- my $pf = "\t";- foreach $hz (@hzlist) {- my @values = compute_values($hz);- print "$pf$hz => [\n";- while (scalar(@values)) {- my $bit;- foreach $bit (32) {- my $m = shift(@values);- my $a = shift(@values);- my $s = shift(@values);- print "\t\t", perlvals($m,$a,$s), ",\n";- }- my $n = shift(@values);- my $d = shift(@values);- print "\t\t", perlvals($n,$d), ",\n";- }- print "\t]";- $pf = ', ';- }- print "\n);\n";-} else {- $hz += 0; # Force to number- if ($hz < 1) {- die "Usage: $0 HZ\n";- }-- @val = @{$canned_values{$hz}};- if (!defined(@val)) {- @val = compute_values($hz);- }- output($hz, @val);-}-exit 0;\0ÿôèº{.nÇ+‰·Ÿ®‰­†+%ŠËÿ±éÝ¶\x17¥Šwÿº{.nÇ+‰·¥Š{±þG«éÿŠ{ayº\x1dÊ‡Ú™ë,j\a­¢f£¢·hšïêÿ‘êçz_è®\x03(­éšŽŠÝ¢j"ú\x1a¶^[m§ÿÿ¾\a«þG«éÿ¢¸?™¨è­Ú&£ø§~á¶iO•æ¬z·švØ^\x14\x04\x1a¶^[m§ÿÿÃ\fÿ¶ìÿ¢¸?–I¥