diff options
| -rw-r--r-- | kernel/Makefile | 16 | ||||
| -rw-r--r-- | kernel/timeconst.bc | 108 | ||||
| -rw-r--r-- | kernel/timeconst.pl | 378 |
3 files changed, 120 insertions, 382 deletions
diff --git a/kernel/Makefile b/kernel/Makefile index 6c072b6..ab1e038 100644 --- a/kernel/Makefile +++ b/kernel/Makefile @@ -127,11 +127,19 @@ $(obj)/config_data.h: $(obj)/config_data.gz FORCE $(obj)/time.o: $(obj)/timeconst.h -quiet_cmd_timeconst = TIMEC $@ - cmd_timeconst = $(PERL) $< $(CONFIG_HZ) > $@ +quiet_cmd_hzfile = HZFILE $@ + cmd_hzfile = echo "hz=$(CONFIG_HZ)" > $@ + +targets += hz.bc +$(obj)/hz.bc: $(objtree)/include/config/hz.h FORCE + $(call if_changed,hzfile) + +quiet_cmd_bc = BC $@ + cmd_bc = bc -q $(filter-out FORCE,$^) > $@ + targets += timeconst.h -$(obj)/timeconst.h: $(src)/timeconst.pl FORCE - $(call if_changed,timeconst) +$(obj)/timeconst.h: $(obj)/hz.bc $(src)/timeconst.bc FORCE + $(call if_changed,bc) ifeq ($(CONFIG_MODULE_SIG),y) # diff --git a/kernel/timeconst.bc b/kernel/timeconst.bc new file mode 100644 index 0000000..511bdf2 --- /dev/null +++ b/kernel/timeconst.bc @@ -0,0 +1,108 @@ +scale=0 + +define gcd(a,b) { + auto t; + while (b) { + t = b; + b = a % b; + a = t; + } + return a; +} + +/* Division by reciprocal multiplication. */ +define fmul(b,n,d) { + return (2^b*n+d-1)/d; +} + +/* Adjustment factor when a ceiling value is used. Use as: + (imul * n) + (fmulxx * n + fadjxx) >> xx) */ +define fadj(b,n,d) { + auto v; + d = d/gcd(n,d); + v = 2^b*(d-1)/d; + return v; +} + +/* Compute the appropriate mul/adj values as well as a shift count, + which brings the mul value into the range 2^b-1 <= x < 2^b. Such + a shift value will be correct in the signed integer range and off + by at most one in the upper half of the unsigned range. */ +define fmuls(b,n,d) { + auto s, m; + for (s = 0; 1; s++) { + m = fmul(s,n,d); + if (m >= 2^(b-1)) + return s; + } + return 0; +} + +define timeconst(hz) { + print "/* Automatically generated by kernel/timeconst.bc */\n" + print "/* Time conversion constants for HZ == ", hz, " */\n" + print "\n" + + print "#ifndef KERNEL_TIMECONST_H\n" + print "#define KERNEL_TIMECONST_H\n\n" + + print "#include <linux/param.h>\n" + print "#include <linux/types.h>\n\n" + + print "#if HZ != ", hz, "\n" + print "#error \qkernel/timeconst.h has the wrong HZ value!\q\n" + print "#endif\n\n" + + if (hz < 2) { + print "#error Totally bogus HZ value!\n" + } else { + s=fmuls(32,1000,hz) + obase=16 + print "#define HZ_TO_MSEC_MUL32\tU64_C(0x", fmul(s,1000,hz), ")\n" + print "#define HZ_TO_MSEC_ADJ32\tU64_C(0x", fadj(s,1000,hz), ")\n" + obase=10 + print "#define HZ_TO_MSEC_SHR32\t", s, "\n" + + s=fmuls(32,hz,1000) + obase=16 + print "#define MSEC_TO_HZ_MUL32\tU64_C(0x", fmul(s,hz,1000), ")\n" + print "#define MSEC_TO_HZ_ADJ32\tU64_C(0x", fadj(s,hz,1000), ")\n" + obase=10 + print "#define MSEC_TO_HZ_SHR32\t", s, "\n" + + obase=10 + cd=gcd(hz,1000) + print "#define HZ_TO_MSEC_NUM\t\t", 1000/cd, "\n" + print "#define HZ_TO_MSEC_DEN\t\t", hz/cd, "\n" + print "#define MSEC_TO_HZ_NUM\t\t", hz/cd, "\n" + print "#define MSEC_TO_HZ_DEN\t\t", 1000/cd, "\n" + print "\n" + + s=fmuls(32,1000000,hz) + obase=16 + print "#define HZ_TO_USEC_MUL32\tU64_C(0x", fmul(s,1000000,hz), ")\n" + print "#define HZ_TO_USEC_ADJ32\tU64_C(0x", fadj(s,1000000,hz), ")\n" + obase=10 + print "#define HZ_TO_USEC_SHR32\t", s, "\n" + + s=fmuls(32,hz,1000000) + obase=16 + print "#define USEC_TO_HZ_MUL32\tU64_C(0x", fmul(s,hz,1000000), ")\n" + print "#define USEC_TO_HZ_ADJ32\tU64_C(0x", fadj(s,hz,1000000), ")\n" + obase=10 + print "#define USEC_TO_HZ_SHR32\t", s, "\n" + + obase=10 + cd=gcd(hz,1000000) + print "#define HZ_TO_USEC_NUM\t\t", 1000000/cd, "\n" + print "#define HZ_TO_USEC_DEN\t\t", hz/cd, "\n" + print "#define USEC_TO_HZ_NUM\t\t", hz/cd, "\n" + print "#define USEC_TO_HZ_DEN\t\t", 1000000/cd, "\n" + print "\n" + + print "#endif /* KERNEL_TIMECONST_H */\n" + } + halt +} + +timeconst(hz) diff --git a/kernel/timeconst.pl b/kernel/timeconst.pl deleted file mode 100644 index eb51d76..0000000 --- a/kernel/timeconst.pl +++ /dev/null @@ -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; |
