Skip to content

Commit

Permalink
Make constants in kernel/timeconst.h fixed 64 bits
Browse files Browse the repository at this point in the history 
Force constants in kernel/timeconst.h (except shift counts) to be 64 bits,
using U64_C() constructor macros, and eliminate constants that cannot
be represented at all in 64 bits.  This avoids warnings with some gcc
versions.

Drop generating 64-bit constants, since we have no real hope of
getting a full set (operation on 64-bit values requires a 128-bit
intermediate result, which gcc only supports on 64-bit platforms, and
only with libgcc support on some.)  Note that the use of these
constants does not depend on if we are on a 32- or 64-bit architecture.

This resolves Bugzilla 10153.

Signed-off-by: H. Peter Anvin <[email protected]>
  • Loading branch information
H. Peter Anvin committed May 2, 2008
1 parent c25bd29 commit b9095fd
Show file tree
Hide file tree
Showing 2 changed files with 52 additions and 76 deletions.
8 changes: 4 additions & 4 deletions kernel/time.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -246,7 +246,7 @@ unsigned int inline jiffies_to_msecs(const unsigned long j)
return (j + (HZ / MSEC_PER_SEC) - 1)/(HZ / MSEC_PER_SEC);
#else
# if BITS_PER_LONG == 32
return ((u64)HZ_TO_MSEC_MUL32 * j) >> HZ_TO_MSEC_SHR32;
return (HZ_TO_MSEC_MUL32 * j) >> HZ_TO_MSEC_SHR32;
# else
return (j * HZ_TO_MSEC_NUM) / HZ_TO_MSEC_DEN;
# endif
Expand All @@ -262,7 +262,7 @@ unsigned int inline jiffies_to_usecs(const unsigned long j)
return (j + (HZ / USEC_PER_SEC) - 1)/(HZ / USEC_PER_SEC);
#else
# if BITS_PER_LONG == 32
return ((u64)HZ_TO_USEC_MUL32 * j) >> HZ_TO_USEC_SHR32;
return (HZ_TO_USEC_MUL32 * j) >> HZ_TO_USEC_SHR32;
# else
return (j * HZ_TO_USEC_NUM) / HZ_TO_USEC_DEN;
# endif
Expand Down Expand Up @@ -476,7 +476,7 @@ unsigned long msecs_to_jiffies(const unsigned int m)
if (HZ > MSEC_PER_SEC && m > jiffies_to_msecs(MAX_JIFFY_OFFSET))
return MAX_JIFFY_OFFSET;

return ((u64)MSEC_TO_HZ_MUL32 * m + MSEC_TO_HZ_ADJ32)
return (MSEC_TO_HZ_MUL32 * m + MSEC_TO_HZ_ADJ32)
>> MSEC_TO_HZ_SHR32;
#endif
}
Expand All @@ -491,7 +491,7 @@ unsigned long usecs_to_jiffies(const unsigned int u)
#elif HZ > USEC_PER_SEC && !(HZ % USEC_PER_SEC)
return u * (HZ / USEC_PER_SEC);
#else
return ((u64)USEC_TO_HZ_MUL32 * u + USEC_TO_HZ_ADJ32)
return (USEC_TO_HZ_MUL32 * u + USEC_TO_HZ_ADJ32)
>> USEC_TO_HZ_SHR32;
#endif
}
Expand Down
120 changes: 48 additions & 72 deletions kernel/timeconst.pl
View file
Original file line number Diff line number Diff line change
@@ -1,7 +1,7 @@
#!/usr/bin/perl
# -----------------------------------------------------------------------
#
# Copyright 2007 rPath, Inc. - All Rights Reserved
# 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
Expand All @@ -20,198 +20,138 @@
%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,
]
);
Expand Down Expand Up @@ -264,14 +204,23 @@ ($$$)
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, $hz);
return ($m->as_hex(), $a->as_hex(), $s);
return (bignum_hex($m), bignum_hex($a), $s);
}

# Provides numerator, denominator values
Expand All @@ -288,12 +237,10 @@ ($$)

# 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;
Expand All @@ -318,6 +265,19 @@ ($)
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) = @_;
Expand All @@ -331,6 +291,7 @@ ($@)
print "\n";

print "#include <linux/param.h>\n";
print "#include <linux/types.h>\n";

print "\n";
print "#if HZ != $hz\n";
Expand All @@ -340,22 +301,37 @@ ($@)

foreach $pfx ('HZ_TO_MSEC','MSEC_TO_HZ',
'HZ_TO_USEC','USEC_TO_HZ') {
foreach $bit (32, 64) {
foreach $bit (32) {
foreach $suf ('MUL', 'ADJ', 'SHR') {
printf "#define %-23s %s\n",
"${pfx}_$suf$bit", shift(@val);
outputval("${pfx}_$suf$bit", shift(@val));
}
}
foreach $suf ('NUM', 'DEN') {
printf "#define %-23s %s\n",
"${pfx}_$suf", shift(@val);
outputval("${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
Expand All @@ -373,15 +349,15 @@ ($@)
print "$pf$hz => [\n";
while (scalar(@values)) {
my $bit;
foreach $bit (32, 64) {
foreach $bit (32) {
my $m = shift(@values);
my $a = shift(@values);
my $s = shift(@values);
print "\t\t\'",$m,"\',\'",$a,"\',",$s,",\n";
print "\t\t", perlvals($m,$a,$s), ",\n";
}
my $n = shift(@values);
my $d = shift(@values);
print "\t\t",$n,',',$d,",\n";
print "\t\t", perlvals($n,$d), ",\n";
}
print "\t]";
$pf = ', ';
Expand Down

0 comments on commit b9095fd

Please sign in to comment.