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Diffstat (limited to 'kernel/timeconst.pl')
| -rw-r--r-- | kernel/timeconst.pl | 402 |
1 files changed, 402 insertions, 0 deletions
diff --git a/kernel/timeconst.pl b/kernel/timeconst.pl new file mode 100644 index 00000000000..62b1287932e --- /dev/null +++ b/kernel/timeconst.pl @@ -0,0 +1,402 @@ +#!/usr/bin/perl +# ----------------------------------------------------------------------- +# +# Copyright 2007 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, + '0xa6aaaaaaaaaaaaab','0x2aaaaaaaaaaaaaa',58, + 125,3, + '0xc49ba5e4','0x1fbe76c8b4',37, + '0xc49ba5e353f7ceda','0x1fbe76c8b439581062',69, + 3,125, + '0xa2c2aaab','0xaaaa',16, + '0xa2c2aaaaaaaaaaab','0xaaaaaaaaaaaa',48, + 125000,3, + '0xc9539b89','0x7fffbce4217d',47, + '0xc9539b8887229e91','0x7fffbce4217d2849cb25',79, + 3,125000, + ], 32 => [ + '0xfa000000','0x6000000',27, + '0xfa00000000000000','0x600000000000000',59, + 125,4, + '0x83126e98','0xfdf3b645a',36, + '0x83126e978d4fdf3c','0xfdf3b645a1cac0831',68, + 4,125, + '0xf4240000','0x0',17, + '0xf424000000000000','0x0',49, + 31250,1, + '0x8637bd06','0x3fff79c842fa',46, + '0x8637bd05af6c69b6','0x3fff79c842fa5093964a',78, + 1,31250, + ], 48 => [ + '0xa6aaaaab','0x6aaaaaa',27, + '0xa6aaaaaaaaaaaaab','0x6aaaaaaaaaaaaaa',59, + 125,6, + '0xc49ba5e4','0xfdf3b645a',36, + '0xc49ba5e353f7ceda','0xfdf3b645a1cac0831',68, + 6,125, + '0xa2c2aaab','0x15555',17, + '0xa2c2aaaaaaaaaaab','0x1555555555555',49, + 62500,3, + '0xc9539b89','0x3fffbce4217d',46, + '0xc9539b8887229e91','0x3fffbce4217d2849cb25',78, + 3,62500, + ], 64 => [ + '0xfa000000','0xe000000',28, + '0xfa00000000000000','0xe00000000000000',60, + 125,8, + '0x83126e98','0x7ef9db22d',35, + '0x83126e978d4fdf3c','0x7ef9db22d0e560418',67, + 8,125, + '0xf4240000','0x0',18, + '0xf424000000000000','0x0',50, + 15625,1, + '0x8637bd06','0x1fff79c842fa',45, + '0x8637bd05af6c69b6','0x1fff79c842fa5093964a',77, + 1,15625, + ], 100 => [ + '0xa0000000','0x0',28, + '0xa000000000000000','0x0',60, + 10,1, + '0xcccccccd','0x733333333',35, + '0xcccccccccccccccd','0x73333333333333333',67, + 1,10, + '0x9c400000','0x0',18, + '0x9c40000000000000','0x0',50, + 10000,1, + '0xd1b71759','0x1fff2e48e8a7',45, + '0xd1b71758e219652c','0x1fff2e48e8a71de69ad4',77, + 1,10000, + ], 122 => [ + '0x8325c53f','0xfbcda3a',28, + '0x8325c53ef368eb05','0xfbcda3ac10c9714',60, + 500,61, + '0xf9db22d1','0x7fbe76c8b',35, + '0xf9db22d0e560418a','0x7fbe76c8b43958106',67, + 61,500, + '0x8012e2a0','0x3ef36',18, + '0x8012e29f79b47583','0x3ef368eb04325',50, + 500000,61, + '0xffda4053','0x1ffffbce4217',45, + '0xffda4052d666a983','0x1ffffbce4217d2849cb2',77, + 61,500000, + ], 128 => [ + '0xfa000000','0x1e000000',29, + '0xfa00000000000000','0x1e00000000000000',61, + 125,16, + '0x83126e98','0x3f7ced916',34, + '0x83126e978d4fdf3c','0x3f7ced916872b020c',66, + 16,125, + '0xf4240000','0x40000',19, + '0xf424000000000000','0x4000000000000',51, + 15625,2, + '0x8637bd06','0xfffbce4217d',44, + '0x8637bd05af6c69b6','0xfffbce4217d2849cb25',76, + 2,15625, + ], 200 => [ + '0xa0000000','0x0',29, + '0xa000000000000000','0x0',61, + 5,1, + '0xcccccccd','0x333333333',34, + '0xcccccccccccccccd','0x33333333333333333',66, + 1,5, + '0x9c400000','0x0',19, + '0x9c40000000000000','0x0',51, + 5000,1, + '0xd1b71759','0xfff2e48e8a7',44, + '0xd1b71758e219652c','0xfff2e48e8a71de69ad4',76, + 1,5000, + ], 250 => [ + '0x80000000','0x0',29, + '0x8000000000000000','0x0',61, + 4,1, + '0x80000000','0x180000000',33, + '0x8000000000000000','0x18000000000000000',65, + 1,4, + '0xfa000000','0x0',20, + '0xfa00000000000000','0x0',52, + 4000,1, + '0x83126e98','0x7ff7ced9168',43, + '0x83126e978d4fdf3c','0x7ff7ced916872b020c4',75, + 1,4000, + ], 256 => [ + '0xfa000000','0x3e000000',30, + '0xfa00000000000000','0x3e00000000000000',62, + 125,32, + '0x83126e98','0x1fbe76c8b',33, + '0x83126e978d4fdf3c','0x1fbe76c8b43958106',65, + 32,125, + '0xf4240000','0xc0000',20, + '0xf424000000000000','0xc000000000000',52, + 15625,4, + '0x8637bd06','0x7ffde7210be',43, + '0x8637bd05af6c69b6','0x7ffde7210be9424e592',75, + 4,15625, + ], 300 => [ + '0xd5555556','0x2aaaaaaa',30, + '0xd555555555555556','0x2aaaaaaaaaaaaaaa',62, + 10,3, + '0x9999999a','0x1cccccccc',33, + '0x999999999999999a','0x1cccccccccccccccc',65, + 3,10, + '0xd0555556','0xaaaaa',20, + '0xd055555555555556','0xaaaaaaaaaaaaa',52, + 10000,3, + '0x9d495183','0x7ffcb923a29',43, + '0x9d495182a9930be1','0x7ffcb923a29c779a6b5',75, + 3,10000, + ], 512 => [ + '0xfa000000','0x7e000000',31, + '0xfa00000000000000','0x7e00000000000000',63, + 125,64, + '0x83126e98','0xfdf3b645',32, + '0x83126e978d4fdf3c','0xfdf3b645a1cac083',64, + 64,125, + '0xf4240000','0x1c0000',21, + '0xf424000000000000','0x1c000000000000',53, + 15625,8, + '0x8637bd06','0x3ffef39085f',42, + '0x8637bd05af6c69b6','0x3ffef39085f4a1272c9',74, + 8,15625, + ], 1000 => [ + '0x80000000','0x0',31, + '0x8000000000000000','0x0',63, + 1,1, + '0x80000000','0x0',31, + '0x8000000000000000','0x0',63, + 1,1, + '0xfa000000','0x0',22, + '0xfa00000000000000','0x0',54, + 1000,1, + '0x83126e98','0x1ff7ced9168',41, + '0x83126e978d4fdf3c','0x1ff7ced916872b020c4',73, + 1,1000, + ], 1024 => [ + '0xfa000000','0xfe000000',32, + '0xfa00000000000000','0xfe00000000000000',64, + 125,128, + '0x83126e98','0x7ef9db22',31, + '0x83126e978d4fdf3c','0x7ef9db22d0e56041',63, + 128,125, + '0xf4240000','0x3c0000',22, + '0xf424000000000000','0x3c000000000000',54, + 15625,16, + '0x8637bd06','0x1fff79c842f',41, + '0x8637bd05af6c69b6','0x1fff79c842fa5093964',73, + 16,15625, + ], 1200 => [ + '0xd5555556','0xd5555555',32, + '0xd555555555555556','0xd555555555555555',64, + 5,6, + '0x9999999a','0x66666666',31, + '0x999999999999999a','0x6666666666666666',63, + 6,5, + '0xd0555556','0x2aaaaa',22, + '0xd055555555555556','0x2aaaaaaaaaaaaa',54, + 2500,3, + '0x9d495183','0x1ffcb923a29',41, + '0x9d495182a9930be1','0x1ffcb923a29c779a6b5',73, + 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($$$) { + my($b,$n,$d) = @_; + my($s,$m); + my($thres) = bint(1) << ($b-1); + + $n = bint($n); + $d = bint($d); + + for ($s = 0; 1; $s++) { + $m = fmul($s,$n,$d); + return $s if ($m >= $thres); + } + return 0; +} + +# Provides mul, adj, and shr factors for a specific +# (bit, time, hz) combination +sub muladj($$$) { + my($b, $t, $hz) = @_; + my $s = fmuls($b, $t, $hz); + my $m = fmul($s, $t, $hz); + my $a = fadj($s, $t, $hz); + return ($m->as_hex(), $a->as_hex(), $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, muladj(64, $t, $hz)); + push(@val, numden($t, $hz)); + + # xx_TO_HZ + push(@val, muladj(32, $hz, $t)); + push(@val, muladj(64, $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, $hz)); + + return @val; +} + +sub output($@) +{ + 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 "\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', + 'USEC_TO_HZ','HZ_TO_USEC') { + foreach $bit (32, 64) { + foreach $suf ('MUL', 'ADJ', 'SHR') { + printf "#define %-23s %s\n", + "${pfx}_$suf$bit", shift(@val); + } + } + foreach $suf ('NUM', 'DEN') { + printf "#define %-23s %s\n", + "${pfx}_$suf", shift(@val); + } + } + + print "\n"; + print "#endif /* KERNEL_TIMECONST_H */\n"; +} + +($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, 64) { + my $m = shift(@values); + my $a = shift(@values); + my $s = shift(@values); + print "\t\t\'",$m,"\',\'",$a,"\',",$s,",\n"; + } + my $n = shift(@values); + my $d = shift(@values); + print "\t\t",$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; |