Re: [PATCH bpf-next 1/8] libbpf: add common min/max macro to libbpf_internal.h

[Song Liu <liu.song.a23@gmail.com>]

On Mon, Jun 10, 2019 at 9:49 PM Andrii Nakryiko <andriin@fb.com> wrote:
>
> Multiple files in libbpf redefine their own definitions for min/max.
> Let's define them in libbpf_internal.h and use those everywhere.
>
> Signed-off-by: Andrii Nakryiko <andriin@fb.com>

Acked-by: Song Liu <songliubraving@fb.com>


> ---
>  tools/lib/bpf/bpf.c             | 7 ++-----
>  tools/lib/bpf/bpf_prog_linfo.c  | 5 +----
>  tools/lib/bpf/btf.c             | 3 ---
>  tools/lib/bpf/btf_dump.c        | 3 ---
>  tools/lib/bpf/libbpf_internal.h | 7 +++++++
>  5 files changed, 10 insertions(+), 15 deletions(-)
>
> diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c
> index 0d4b4fe10a84..c7d7993c44bb 100644
> --- a/tools/lib/bpf/bpf.c
> +++ b/tools/lib/bpf/bpf.c
> @@ -26,10 +26,11 @@
>  #include <memory.h>
>  #include <unistd.h>
>  #include <asm/unistd.h>
> +#include <errno.h>
>  #include <linux/bpf.h>
>  #include "bpf.h"
>  #include "libbpf.h"
> -#include <errno.h>
> +#include "libbpf_internal.h"
>
>  /*
>   * When building perf, unistd.h is overridden. __NR_bpf is
> @@ -53,10 +54,6 @@
>  # endif
>  #endif
>
> -#ifndef min
> -#define min(x, y) ((x) < (y) ? (x) : (y))
> -#endif
> -
>  static inline __u64 ptr_to_u64(const void *ptr)
>  {
>         return (__u64) (unsigned long) ptr;
> diff --git a/tools/lib/bpf/bpf_prog_linfo.c b/tools/lib/bpf/bpf_prog_linfo.c
> index 6978314ea7f6..8c67561c93b0 100644
> --- a/tools/lib/bpf/bpf_prog_linfo.c
> +++ b/tools/lib/bpf/bpf_prog_linfo.c
> @@ -6,10 +6,7 @@
>  #include <linux/err.h>
>  #include <linux/bpf.h>
>  #include "libbpf.h"
> -
> -#ifndef min
> -#define min(x, y) ((x) < (y) ? (x) : (y))
> -#endif
> +#include "libbpf_internal.h"
>
>  struct bpf_prog_linfo {
>         void *raw_linfo;
> diff --git a/tools/lib/bpf/btf.c b/tools/lib/bpf/btf.c
> index b2478e98c367..467224feb43b 100644
> --- a/tools/lib/bpf/btf.c
> +++ b/tools/lib/bpf/btf.c
> @@ -16,9 +16,6 @@
>  #include "libbpf_internal.h"
>  #include "hashmap.h"
>
> -#define max(a, b) ((a) > (b) ? (a) : (b))
> -#define min(a, b) ((a) < (b) ? (a) : (b))
> -
>  #define BTF_MAX_NR_TYPES 0x7fffffff
>  #define BTF_MAX_STR_OFFSET 0x7fffffff
>
> diff --git a/tools/lib/bpf/btf_dump.c b/tools/lib/bpf/btf_dump.c
> index 4b22db77e2cc..7065bb5b2752 100644
> --- a/tools/lib/bpf/btf_dump.c
> +++ b/tools/lib/bpf/btf_dump.c
> @@ -18,9 +18,6 @@
>  #include "libbpf.h"
>  #include "libbpf_internal.h"
>
> -#define min(x, y) ((x) < (y) ? (x) : (y))
> -#define max(x, y) ((x) < (y) ? (y) : (x))
> -
>  static const char PREFIXES[] = "\t\t\t\t\t\t\t\t\t\t\t\t\t";
>  static const size_t PREFIX_CNT = sizeof(PREFIXES) - 1;
>
> diff --git a/tools/lib/bpf/libbpf_internal.h b/tools/lib/bpf/libbpf_internal.h
> index 850f7bdec5cb..554a7856dc2d 100644
> --- a/tools/lib/bpf/libbpf_internal.h
> +++ b/tools/lib/bpf/libbpf_internal.h
> @@ -23,6 +23,13 @@
>  #define BTF_PARAM_ENC(name, type) (name), (type)
>  #define BTF_VAR_SECINFO_ENC(type, offset, size) (type), (offset), (size)
>
> +#ifndef min
> +# define min(x, y) ((x) < (y) ? (x) : (y))
> +#endif
> +#ifndef max
> +# define max(x, y) ((x) < (y) ? (y) : (x))
> +#endif
> +
>  extern void libbpf_print(enum libbpf_print_level level,
>                          const char *format, ...)
>         __attribute__((format(printf, 2, 3)));
> --
> 2.17.1
>