1#!/bin/bash 2# SPDX-License-Identifier: GPL-2.0+ 3# 4# Create an initrd directory if one does not already exist. 5# 6# Copyright (C) IBM Corporation, 2013 7# 8# Author: Connor Shu <Connor.Shu@ibm.com> 9 10D=tools/testing/selftests/rcutorture 11 12# Prerequisite checks 13if [ ! -d "$D" ]; then 14 echo >&2 "$D does not exist: Malformed kernel source tree?" 15 exit 1 16fi 17if [ -s "$D/initrd/init" ]; then 18 echo "$D/initrd/init already exists, no need to create it" 19 exit 0 20fi 21 22# Create a C-language initrd/init infinite-loop program and statically 23# link it. This results in a very small initrd. 24echo "Creating a statically linked C-language initrd" 25cd $D 26mkdir -p initrd 27cd initrd 28cat > init.c << '___EOF___' 29#ifndef NOLIBC 30#include <unistd.h> 31#include <sys/time.h> 32#endif 33 34volatile unsigned long delaycount; 35 36int main(int argc, char *argv[]) 37{ 38 int i; 39 struct timeval tv; 40 struct timeval tvb; 41 42 printf("Torture-test rudimentary init program started, command line:\n"); 43 for (i = 0; i < argc; i++) 44 printf(" %s", argv[i]); 45 printf("\n"); 46 for (;;) { 47 sleep(1); 48 /* Need some userspace time. */ 49 if (gettimeofday(&tvb, NULL)) 50 continue; 51 do { 52 for (i = 0; i < 1000 * 100; i++) 53 delaycount = i * i; 54 if (gettimeofday(&tv, NULL)) 55 break; 56 tv.tv_sec -= tvb.tv_sec; 57 if (tv.tv_sec > 1) 58 break; 59 tv.tv_usec += tv.tv_sec * 1000 * 1000; 60 tv.tv_usec -= tvb.tv_usec; 61 } while (tv.tv_usec < 1000); 62 } 63 return 0; 64} 65___EOF___ 66 67# build using nolibc on supported archs (smaller executable) and fall 68# back to regular glibc on other ones. 69if echo -e "#if __x86_64__||__i386__||__i486__||__i586__||__i686__" \ 70 "||__ARM_EABI__||__aarch64__||(__mips__ && _ABIO32)" \ 71 "||__powerpc__||(__riscv && __riscv_xlen == 64)" \ 72 "||__s390x__||__loongarch__" \ 73 "\nyes\n#endif" \ 74 | ${CROSS_COMPILE}gcc -E -nostdlib -xc - \ 75 | grep -q '^yes'; then 76 # architecture supported by nolibc 77 ${CROSS_COMPILE}gcc -fno-asynchronous-unwind-tables -fno-ident \ 78 -nostdlib -include ../../../../include/nolibc/nolibc.h \ 79 -s -static -Os -o init init.c -lgcc 80 ret=$? 81else 82 ${CROSS_COMPILE}gcc -s -static -Os -o init init.c 83 ret=$? 84fi 85 86if [ "$ret" -ne 0 ] 87then 88 echo "Failed to create a statically linked C-language initrd" 89 exit "$ret" 90fi 91 92rm init.c 93echo "Done creating a statically linked C-language initrd" 94 95exit 0 96