On 26/02/2025 11:44, Thomas Weißschuh wrote:
vdso_standalone_test_x86 provides its own ASM syscall wrappers and _start() implementation. The in-tree nolibc library already provides this functionality for multiple architectures. By making use of nolibc, the standalone testcase can be built from the exact same codebase as the non-standalone version.
Signed-off-by: Thomas Weißschuh thomas.weissschuh@linutronix.de
Reviewed-by: Vincenzo Frascino vincenzo.frascino@arm.com
tools/testing/selftests/vDSO/Makefile | 8 +- .../selftests/vDSO/vdso_standalone_test_x86.c | 168 +-------------------- 2 files changed, 7 insertions(+), 169 deletions(-)
diff --git a/tools/testing/selftests/vDSO/Makefile b/tools/testing/selftests/vDSO/Makefile index bc8ca186fb877dc11740c37f1e07e45e84c2ae92..12a0614b9fd4983deffe5d6a7cfa06ba8d92a516 100644 --- a/tools/testing/selftests/vDSO/Makefile +++ b/tools/testing/selftests/vDSO/Makefile @@ -22,13 +22,17 @@ include ../lib.mk CFLAGS += $(TOOLS_INCLUDES) +CFLAGS_NOLIBC := -nostdlib -nostdinc -ffreestanding -fno-asynchronous-unwind-tables \
-fno-stack-protector -include $(top_srcdir)/tools/include/nolibc/nolibc.h \-I$(top_srcdir)/tools/include/nolibc/ $(KHDR_INCLUDES)$(OUTPUT)/vdso_test_gettimeofday: parse_vdso.c vdso_test_gettimeofday.c $(OUTPUT)/vdso_test_getcpu: parse_vdso.c vdso_test_getcpu.c $(OUTPUT)/vdso_test_abi: parse_vdso.c vdso_test_abi.c $(OUTPUT)/vdso_test_clock_getres: vdso_test_clock_getres.c -$(OUTPUT)/vdso_standalone_test_x86: vdso_standalone_test_x86.c parse_vdso.c -$(OUTPUT)/vdso_standalone_test_x86: CFLAGS +=-nostdlib -fno-asynchronous-unwind-tables -fno-stack-protector +$(OUTPUT)/vdso_standalone_test_x86: vdso_standalone_test_x86.c parse_vdso.c | headers +$(OUTPUT)/vdso_standalone_test_x86: CFLAGS:=$(CFLAGS_NOLIBC) $(CFLAGS) $(OUTPUT)/vdso_test_correctness: vdso_test_correctness.c $(OUTPUT)/vdso_test_correctness: LDFLAGS += -ldl diff --git a/tools/testing/selftests/vDSO/vdso_standalone_test_x86.c b/tools/testing/selftests/vDSO/vdso_standalone_test_x86.c deleted file mode 100644 index 500608f89c66b5747e3d845ebc54e4c3a35b6ccd..0000000000000000000000000000000000000000 --- a/tools/testing/selftests/vDSO/vdso_standalone_test_x86.c +++ /dev/null @@ -1,167 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-only -/*
- vdso_test.c: Sample code to test parse_vdso.c on x86
- Copyright (c) 2011-2014 Andy Lutomirski
- You can amuse yourself by compiling with:
- gcc -std=gnu99 -nostdlib
-Os -fno-asynchronous-unwind-tables -flto -lgcc_s
vdso_standalone_test_x86.c parse_vdso.c
- to generate a small binary. On x86_64, you can omit -lgcc_s
- if you want the binary to be completely standalone.
- */
-#include <sys/syscall.h> -#include <sys/time.h> -#include <unistd.h> -#include <stdint.h> -#include <linux/auxvec.h>
-#include "parse_vdso.h"
-/* We need some libc functions... */ -int strcmp(const char *a, const char *b) -{
- /* This implementation is buggy: it never returns -1. */
- while (*a || *b) {
if (*a != *b)return 1;if (*a == 0 || *b == 0)return 1;a++;b++;- }
- return 0;
-}
-/*
- The clang build needs this, although gcc does not.
- Stolen from lib/string.c.
- */
-void *memcpy(void *dest, const void *src, size_t count) -{
- char *tmp = dest;
- const char *s = src;
- while (count--)
*tmp++ = *s++;- return dest;
-}
-/* ...and two syscalls. This is x86-specific. */ -static inline long x86_syscall3(long nr, long a0, long a1, long a2) -{
- long ret;
-#ifdef __x86_64__
- asm volatile ("syscall" : "=a" (ret) : "a" (nr),
"D" (a0), "S" (a1), "d" (a2) :"cc", "memory", "rcx","r8", "r9", "r10", "r11" );-#else
- asm volatile ("int $0x80" : "=a" (ret) : "a" (nr),
"b" (a0), "c" (a1), "d" (a2) :"cc", "memory" );-#endif
- return ret;
-}
-static inline long linux_write(int fd, const void *data, size_t len) -{
- return x86_syscall3(__NR_write, fd, (long)data, (long)len);
-}
-static inline void linux_exit(int code) -{
- x86_syscall3(__NR_exit, code, 0, 0);
-}
-void to_base10(char *lastdig, time_t n) -{
- while (n) {
*lastdig = (n % 10) + '0';n /= 10;lastdig--;- }
-}
-unsigned long getauxval(const unsigned long *auxv, unsigned long type) -{
- unsigned long ret;
- if (!auxv)
return 0;- while (1) {
if (!auxv[0] && !auxv[1]) {ret = 0;break;}if (auxv[0] == type) {ret = auxv[1];break;}auxv += 2;- }
- return ret;
-}
-void c_main(void **stack) -{
- /* Parse the stack */
- long argc = (long)*stack;
- stack += argc + 2;
- /* Now we're pointing at the environment. Skip it. */
- while(*stack)
stack++;- stack++;
- /* Now we're pointing at auxv. Initialize the vDSO parser. */
- vdso_init_from_sysinfo_ehdr(getauxval((unsigned long *)stack, AT_SYSINFO_EHDR));
- /* Find gettimeofday. */
- typedef long (*gtod_t)(struct timeval *tv, struct timezone *tz);
- gtod_t gtod = (gtod_t)vdso_sym("LINUX_2.6", "__vdso_gettimeofday");
- if (!gtod)
linux_exit(1);- struct timeval tv;
- long ret = gtod(&tv, 0);
- if (ret == 0) {
char buf[] = "The time is .000000\n";to_base10(buf + 31, tv.tv_sec);to_base10(buf + 38, tv.tv_usec);linux_write(1, buf, sizeof(buf) - 1);- } else {
linux_exit(ret);- }
- linux_exit(0);
-}
-/*
- This is the real entry point. It passes the initial stack into
- the C entry point.
- */
-asm (
- ".text\n"
- ".global _start\n"
- ".type _start,@function\n"
- "_start:\n\t"
-#ifdef __x86_64__
- "mov %rsp,%rdi\n\t"
- "and $-16,%rsp\n\t"
- "sub $8,%rsp\n\t"
- "jmp c_main"
-#else
- "push %esp\n\t"
- "call c_main\n\t"
- "int $3"
-#endif
- );
diff --git a/tools/testing/selftests/vDSO/vdso_standalone_test_x86.c b/tools/testing/selftests/vDSO/vdso_standalone_test_x86.c new file mode 120000 index 0000000000000000000000000000000000000000..4d3d96f1e440c965474681a6f35375a60b3921be --- /dev/null +++ b/tools/testing/selftests/vDSO/vdso_standalone_test_x86.c @@ -0,0 +1 @@ +vdso_test_gettimeofday.c \ No newline at end of file