From: shuah <shuah@kernel.org>
To: Mark Brown <broonie@kernel.org>
Cc: linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org,
shuah <shuah@kernel.org>
Subject: Re: [PATCH 2/3] selftests: vdso: Use a header file to prototype parse_vdso API
Date: Tue, 19 May 2020 11:29:10 -0600 [thread overview]
Message-ID: <aaeb0619-68d2-18f8-f72a-b8b37f348b4e@kernel.org> (raw)
In-Reply-To: <20200505174728.46594-3-broonie@kernel.org>
On 5/5/20 11:47 AM, Mark Brown wrote:
> 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: Mark Brown <broonie@kernel.org>
> ---
> tools/testing/selftests/vDSO/parse_vdso.c | 24 +-------------
> tools/testing/selftests/vDSO/parse_vdso.h | 31 +++++++++++++++++++
> .../selftests/vDSO/vdso_standalone_test_x86.c | 4 +--
> .../selftests/vDSO/vdso_test_gettimeofday.c | 5 +--
> 4 files changed, 34 insertions(+), 30 deletions(-)
> create mode 100644 tools/testing/selftests/vDSO/parse_vdso.h
>
> diff --git a/tools/testing/selftests/vDSO/parse_vdso.c b/tools/testing/selftests/vDSO/parse_vdso.c
> index 1dbb4b87268f..413f75620a35 100644
> --- a/tools/testing/selftests/vDSO/parse_vdso.c
> +++ b/tools/testing/selftests/vDSO/parse_vdso.c
> @@ -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
> diff --git a/tools/testing/selftests/vDSO/parse_vdso.h b/tools/testing/selftests/vDSO/parse_vdso.h
> new file mode 100644
> index 000000000000..ea4b8635bb0b
> --- /dev/null
> +++ b/tools/testing/selftests/vDSO/parse_vdso.h
> @@ -0,0 +1,31 @@
> +/* 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:
> + */
> +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);
> +
You don't need extern here - this should be in scope?
> +#endif
> diff --git a/tools/testing/selftests/vDSO/vdso_standalone_test_x86.c b/tools/testing/selftests/vDSO/vdso_standalone_test_x86.c
> index 5ac4b00acfbc..8a44ff973ee1 100644
> --- a/tools/testing/selftests/vDSO/vdso_standalone_test_x86.c
> +++ b/tools/testing/selftests/vDSO/vdso_standalone_test_x86.c
> @@ -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);
thanks,
-- Shuah
next prev parent reply other threads:[~2020-05-19 17:29 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-05-05 17:47 [PATCH 0/3] selftests: vdso: Add a selftest for vDSO getcpu() Mark Brown
2020-05-05 17:47 ` [PATCH 1/3] selftests: vdso: Rename vdso_test to vdso_test_gettimeofday Mark Brown
2020-05-05 17:47 ` [PATCH 2/3] selftests: vdso: Use a header file to prototype parse_vdso API Mark Brown
2020-05-19 17:29 ` shuah [this message]
2020-05-19 17:42 ` Mark Brown
2020-05-05 17:47 ` [PATCH 3/3] selftests: vdso: Add a selftest for vDSO getcpu() Mark Brown
2020-05-19 17:11 ` shuah
2020-05-19 17:44 ` Mark Brown
2020-05-22 14:55 ` shuah
2020-05-22 15:12 ` Mark Brown
2020-05-22 15:15 ` shuah
2020-05-22 16:15 ` Mark Brown
2020-05-05 18:17 ` [PATCH 0/3] " shuah
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