diff options
author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 10:05:51 +0000 |
---|---|---|
committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 10:05:51 +0000 |
commit | 5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch) | |
tree | a94efe259b9009378be6d90eb30d2b019d95c194 /tools/testing/selftests/rcutorture/bin/mkinitrd.sh | |
parent | Initial commit. (diff) | |
download | linux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.tar.xz linux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.zip |
Adding upstream version 5.10.209.upstream/5.10.209upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'tools/testing/selftests/rcutorture/bin/mkinitrd.sh')
-rwxr-xr-x | tools/testing/selftests/rcutorture/bin/mkinitrd.sh | 81 |
1 files changed, 81 insertions, 0 deletions
diff --git a/tools/testing/selftests/rcutorture/bin/mkinitrd.sh b/tools/testing/selftests/rcutorture/bin/mkinitrd.sh new file mode 100755 index 000000000..38e424d23 --- /dev/null +++ b/tools/testing/selftests/rcutorture/bin/mkinitrd.sh @@ -0,0 +1,81 @@ +#!/bin/bash +# SPDX-License-Identifier: GPL-2.0+ +# +# Create an initrd directory if one does not already exist. +# +# Copyright (C) IBM Corporation, 2013 +# +# Author: Connor Shu <Connor.Shu@ibm.com> + +D=tools/testing/selftests/rcutorture + +# Prerequisite checks +[ -z "$D" ] && echo >&2 "No argument supplied" && exit 1 +if [ ! -d "$D" ]; then + echo >&2 "$D does not exist: Malformed kernel source tree?" + exit 1 +fi +if [ -s "$D/initrd/init" ]; then + echo "$D/initrd/init already exists, no need to create it" + exit 0 +fi + +# Create a C-language initrd/init infinite-loop program and statically +# link it. This results in a very small initrd. +echo "Creating a statically linked C-language initrd" +cd $D +mkdir -p initrd +cd initrd +cat > init.c << '___EOF___' +#ifndef NOLIBC +#include <unistd.h> +#include <sys/time.h> +#endif + +volatile unsigned long delaycount; + +int main(int argc, int argv[]) +{ + int i; + struct timeval tv; + struct timeval tvb; + + for (;;) { + sleep(1); + /* Need some userspace time. */ + if (gettimeofday(&tvb, NULL)) + continue; + do { + for (i = 0; i < 1000 * 100; i++) + delaycount = i * i; + if (gettimeofday(&tv, NULL)) + break; + tv.tv_sec -= tvb.tv_sec; + if (tv.tv_sec > 1) + break; + tv.tv_usec += tv.tv_sec * 1000 * 1000; + tv.tv_usec -= tvb.tv_usec; + } while (tv.tv_usec < 1000); + } + return 0; +} +___EOF___ + +# build using nolibc on supported archs (smaller executable) and fall +# back to regular glibc on other ones. +if echo -e "#if __x86_64__||__i386__||__i486__||__i586__||__i686__" \ + "||__ARM_EABI__||__aarch64__\nyes\n#endif" \ + | ${CROSS_COMPILE}gcc -E -nostdlib -xc - \ + | grep -q '^yes'; then + # architecture supported by nolibc + ${CROSS_COMPILE}gcc -fno-asynchronous-unwind-tables -fno-ident \ + -nostdlib -include ../../../../include/nolibc/nolibc.h \ + -lgcc -s -static -Os -o init init.c +else + ${CROSS_COMPILE}gcc -s -static -Os -o init init.c +fi + +rm init.c +echo "Done creating a statically linked C-language initrd" + +exit 0 |