#!/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;