* [PATCH v2] replace timeconst bc script with an sh script
[not found] <8a9ffb4b-791d-35d1-bb2a-7b6ad812bff1@ideasonboard.com>
@ 2019-06-20 8:11 ` Ethan Sommer
2019-06-20 8:25 ` Borislav Petkov
0 siblings, 1 reply; 4+ messages in thread
From: Ethan Sommer @ 2019-06-20 8:11 UTC (permalink / raw)
Cc: hpa, Ethan Sommer, Jonathan Corbet, Masahiro Yamada, Randy Dunlap,
Nick Desaulniers, Kees Cook, Joe Perches, Federico Vaga,
Ingo Molnar, Kieran Bingham, Peter Zijlstra (Intel),
Borislav Petkov, Mark Rutland, John Stultz, Corey Minyard,
Thomas Gleixner, linux-doc, linux-kernel
removes the bc build dependency introduced when timeconst.pl was
replaced by timeconst.bc:
70730bca1331 ("kernel: Replace timeconst.pl with a bc script")
Signed-off-by: Ethan Sommer <e5ten.arch@gmail.com>
---
Documentation/process/changes.rst | 6 --
Kbuild | 4 +-
kernel/time/timeconst.bc | 117 -----------------------------
kernel/time/timeconst.sh | 118 ++++++++++++++++++++++++++++++
4 files changed, 120 insertions(+), 125 deletions(-)
delete mode 100644 kernel/time/timeconst.bc
create mode 100755 kernel/time/timeconst.sh
diff --git a/Documentation/process/changes.rst b/Documentation/process/changes.rst
index 18735dc460a0..14347f6752ea 100644
--- a/Documentation/process/changes.rst
+++ b/Documentation/process/changes.rst
@@ -108,12 +108,6 @@ Perl
You will need perl 5 and the following modules: ``Getopt::Long``,
``Getopt::Std``, ``File::Basename``, and ``File::Find`` to build the kernel.
-BC
---
-
-You will need bc to build kernels 3.10 and higher
-
-
OpenSSL
-------
diff --git a/Kbuild b/Kbuild
index 8637fd14135f..2b5f2957cf04 100644
--- a/Kbuild
+++ b/Kbuild
@@ -20,9 +20,9 @@ timeconst-file := include/generated/timeconst.h
targets += $(timeconst-file)
-filechk_gentimeconst = echo $(CONFIG_HZ) | bc -q $<
+filechk_gentimeconst = $(CONFIG_SHELL) $< $(CONFIG_HZ)
-$(timeconst-file): kernel/time/timeconst.bc FORCE
+$(timeconst-file): kernel/time/timeconst.sh FORCE
$(call filechk,gentimeconst)
#####
diff --git a/kernel/time/timeconst.bc b/kernel/time/timeconst.bc
deleted file mode 100644
index 7ed0e0fb5831..000000000000
--- a/kernel/time/timeconst.bc
+++ /dev/null
@@ -1,117 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-
-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/time/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 \qinclude/generated/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"
-
- cd=gcd(hz,1000000000)
- print "#define HZ_TO_NSEC_NUM\t\t", 1000000000/cd, "\n"
- print "#define HZ_TO_NSEC_DEN\t\t", hz/cd, "\n"
- print "#define NSEC_TO_HZ_NUM\t\t", hz/cd, "\n"
- print "#define NSEC_TO_HZ_DEN\t\t", 1000000000/cd, "\n"
- print "\n"
-
- print "#endif /* KERNEL_TIMECONST_H */\n"
- }
- halt
-}
-
-hz = read();
-timeconst(hz)
diff --git a/kernel/time/timeconst.sh b/kernel/time/timeconst.sh
new file mode 100755
index 000000000000..20dd24815ae1
--- /dev/null
+++ b/kernel/time/timeconst.sh
@@ -0,0 +1,118 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+
+if [ -z "$1" ]; then
+ printf '%s <HZ>\n' "$0"
+ exit 1
+else
+ hz="$1"
+fi
+
+# 2 to the power of n
+pot() {
+ local i=1
+ local j=1
+ while [ "${j}" -le "$1" ]; do
+ i="$((i * 2))"
+ j="$((j + 1))"
+ done
+ printf '%s\n' "${i}"
+}
+
+# Greatest common denominator
+gcd() {
+ local i="$1"
+ local j="$2"
+ local k
+ while [ "${j}" -ne 0 ]; do
+ k="${j}"
+ j="$((i % j))"
+ i="${k}"
+ done
+ printf '%s\n' "${i}"
+}
+
+# Division by reciprocal multiplication.
+fmul() {
+ printf '%s\n' "$((($(pot "$1") * $2 + $3 - 1) / $3))"
+}
+
+# Adjustment factor when a ceiling value is used.
+fadj() {
+ local i="$(gcd "$2" "$3")"
+ printf '%s\n' "$(($(pot "$1") * ($3 / i - 1) / ($3 / i)))"
+}
+
+# Compute the appropriate mul/adj values as well as a shift count,
+# which brings the mul value into the range 2^b-1 <= x < 2^b. Such
+# a shift value will be correct in the signed integer range and off
+# by at most one in the upper half of the unsigned range.
+fmuls() {
+ local i=0
+ local j
+ while true; do
+ j="$(fmul "${i}" "$2" "$3")"
+ if [ "${j}" -ge "$(pot "$(($1 - 1))")" ]; then
+ printf '%s\n' "${i}" && return
+ fi
+ i="$((i + 1))"
+ done
+}
+
+printf '/* Automatically generated by kernel/time/timeconst.sh */\n'
+printf '/* Time conversion constants for HZ == %s */\n\n' "$1"
+
+printf '#ifndef KERNEL_TIMECONST_H\n'
+printf '#define KERNEL_TIMECONST_H\n\n'
+
+printf '#include <linux/param.h>\n'
+printf '#include <linux/types.h>\n\n'
+
+printf '#if HZ != %s\n' "$1"
+printf '#error "include/generated/timeconst.h has the wrong HZ value!"\n'
+printf '#endif\n\n'
+
+if [ "$1" -lt 2 ]; then
+ printf '#error Totally bogus HZ value!\n'
+ exit 1
+fi
+
+s="$(fmuls 32 1000 "$1")"
+printf '#define HZ_TO_MSEC_MUL32\tU64_C(0x%X)\n' "$(fmul "${s}" 1000 "$1")"
+printf '#define HZ_TO_MSEC_ADJ32\tU64_C(0x%X)\n' "$(fadj "${s}" 1000 "$1")"
+printf '#define HZ_TO_MSEC_SHR32\t%s\n' "${s}"
+
+s="$(fmuls 32 "$1" 1000)"
+printf '#define MSEC_TO_HZ_MUL32\tU64_C(0x%X)\n' "$(fmul "${s}" "$1" 1000)"
+printf '#define MSEC_TO_HZ_ADJ32\tU64_C(0x%X)\n' "$(fadj "${s}" "$1" 1000)"
+printf '#define MSEC_TO_HZ_SHR32\t%s\n' "${s}"
+
+cd="$(gcd "$1" 1000)"
+printf '#define HZ_TO_MSEC_NUM\t\t%s\n' "$((1000 / cd))"
+printf '#define HZ_TO_MSEC_DEN\t\t%s\n' "$((hz / cd))"
+printf '#define MSEC_TO_HZ_NUM\t\t%s\n' "$((hz / cd))"
+printf '#define MSEC_TO_HZ_DEN\t\t%s\n\n' "$((1000 / cd))"
+
+s="$(fmuls 32 1000000 "$1")"
+printf '#define HZ_TO_USEC_MUL32\tU64_C(0x%X)\n' "$(fmul "${s}" 1000000 "$1")"
+printf '#define HZ_TO_USEC_ADJ32\tU64_C(0x%X)\n' "$(fadj "${s}" 1000000 "$1")"
+printf '#define HZ_TO_USEC_SHR32\t%s\n' "${s}"
+
+s="$(fmuls 32 "$1" 1000000)"
+printf '#define USEC_TO_HZ_MUL32\tU64_C(0x%X)\n' "$(fmul "${s}" "$1" 1000000)"
+printf '#define USEC_TO_HZ_ADJ32\tU64_C(0x%X)\n' "$(fadj "${s}" "$1" 1000000)"
+printf '#define USEC_TO_HZ_SHR32\t%s\n' "${s}"
+
+cd="$(gcd "$1" 1000000)"
+printf '#define HZ_TO_USEC_NUM\t\t%s\n' "$((1000000 / cd))"
+printf '#define HZ_TO_USEC_DEN\t\t%s\n' "$((hz / cd))"
+printf '#define USEC_TO_HZ_NUM\t\t%s\n' "$((hz / cd))"
+printf '#define USEC_TO_HZ_DEN\t\t%s\n' "$((1000000 / cd))"
+
+cd="$(gcd "$1" 1000000000)"
+printf '#define HZ_TO_NSEC_NUM\t\t%s\n' "$((1000000000 / cd))"
+printf '#define HZ_TO_NSEC_DEN\t\t%s\n' "$((hz / cd))"
+printf '#define NSEC_TO_HZ_NUM\t\t%s\n' "$((hz / cd))"
+printf '#define NSEC_TO_HZ_DEN\t\t%s\n' "$((1000000000 / cd))"
+
+printf '\n#endif /* KERNEL_TIMECONST_H */\n'
--
2.22.0
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