Commit cd76ca4d authored by Mark Brown's avatar Mark Brown Committed by Shuah Khan
Browse files

selftests: vdso: Use a header file to prototype parse_vdso API 



Both vdso_test_gettimeofday and vdso_standalone_test_x86 use the library in
parse_vdso.c but each separately declares the API it offers which is not
ideal. Create a header file with prototypes of the functions and use it in
both the library and the tests to ensure that the same prototypes are used
throughout.

Signed-off-by: default avatarMark Brown <broonie@kernel.org>
Signed-off-by: default avatarShuah Khan <skhan@linuxfoundation.org>
parent babf8a97

tools/testing/selftests/vDSO/parse_vdso.c

+1 −23
Original line number Diff line number Diff line
@@ -21,29 +21,7 @@ 
#include <limits.h>

#include <elf.h>



/*

 * To use this vDSO parser, first call one of the vdso_init_* functions.

 * If you've already parsed auxv, then pass the value of AT_SYSINFO_EHDR

 * to vdso_init_from_sysinfo_ehdr.  Otherwise pass auxv to vdso_init_from_auxv.

 * Then call vdso_sym for each symbol you want.  For example, to look up

 * gettimeofday on x86_64, use:

 *

 *     <some pointer> = vdso_sym("LINUX_2.6", "gettimeofday");

 * or

 *     <some pointer> = vdso_sym("LINUX_2.6", "__vdso_gettimeofday");

 *

 * vdso_sym will return 0 if the symbol doesn't exist or if the init function

 * failed or was not called.  vdso_sym is a little slow, so its return value

 * should be cached.

 *

 * vdso_sym is threadsafe; the init functions are not.

 *

 * These are the prototypes:

 */

extern void vdso_init_from_auxv(void *auxv);

extern void vdso_init_from_sysinfo_ehdr(uintptr_t base);

extern void *vdso_sym(const char *version, const char *name);



#include "parse_vdso.h"



/* And here's the code. */

#ifndef ELF_BITS

tools/testing/selftests/vDSO/parse_vdso.h

0 → 100644
+31 −0
Original line number Diff line number Diff line 
/* SPDX-License-Identifier: GPL-2.0-only */



#ifndef PARSE_VDSO_H

#define PARSE_VDSO_H



#include <stdint.h>



/*

 * To use this vDSO parser, first call one of the vdso_init_* functions.

 * If you've already parsed auxv, then pass the value of AT_SYSINFO_EHDR

 * to vdso_init_from_sysinfo_ehdr.  Otherwise pass auxv to vdso_init_from_auxv.

 * Then call vdso_sym for each symbol you want.  For example, to look up

 * gettimeofday on x86_64, use:

 *

 *     <some pointer> = vdso_sym("LINUX_2.6", "gettimeofday");

 * or

 *     <some pointer> = vdso_sym("LINUX_2.6", "__vdso_gettimeofday");

 *

 * vdso_sym will return 0 if the symbol doesn't exist or if the init function

 * failed or was not called.  vdso_sym is a little slow, so its return value

 * should be cached.

 *

 * vdso_sym is threadsafe; the init functions are not.

 *

 * These are the prototypes:

 */

void *vdso_sym(const char *version, const char *name);

void vdso_init_from_sysinfo_ehdr(uintptr_t base);

void vdso_init_from_auxv(void *auxv);



#endif

tools/testing/selftests/vDSO/vdso_standalone_test_x86.c

+1 −3
Original line number Diff line number Diff line
@@ -16,9 +16,7 @@ 
#include <unistd.h>

#include <stdint.h>



extern void *vdso_sym(const char *version, const char *name);

extern void vdso_init_from_sysinfo_ehdr(uintptr_t base);

extern void vdso_init_from_auxv(void *auxv);

#include "parse_vdso.h"



/* We need a libc functions... */

int strcmp(const char *a, const char *b)

tools/testing/selftests/vDSO/vdso_test_gettimeofday.c

+1 −4
Original line number Diff line number Diff line
@@ -17,10 +17,7 @@ 
#include <sys/time.h>



#include "../kselftest.h"



extern void *vdso_sym(const char *version, const char *name);

extern void vdso_init_from_sysinfo_ehdr(uintptr_t base);

extern void vdso_init_from_auxv(void *auxv);

#include "parse_vdso.h"



/*

 * ARM64's vDSO exports its gettimeofday() implementation with a different

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