Re: [PATCH v3 5/5] Lib: sort.h: remove the size argument from the swap function

From: Andy Shevchenko
Date: Wed Apr 03 2019 - 07:33:29 EST


On Tue, Apr 02, 2019 at 11:55:25PM +0300, Andrey Abramov wrote:
> Removes size argument from the swap function because:
> 1) It wasn't used.
> 2) Custom swap function knows what kind of objects it swaps,
> so it already knows their sizes.
>
> Signed-off-by: Andrey Abramov <st5pub@xxxxxxxxx>
> Reviewed by: George Spelvin <lkml@xxxxxxx>

FWIW,
Reviewed-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>

> ---
> arch/x86/kernel/unwind_orc.c | 2 +-
> include/linux/sort.h | 2 +-
> kernel/jump_label.c | 2 +-
> lib/extable.c | 2 +-
> lib/sort.c | 7 +++----
> 5 files changed, 7 insertions(+), 8 deletions(-)
>
> diff --git a/arch/x86/kernel/unwind_orc.c b/arch/x86/kernel/unwind_orc.c
> index 89be1be1790c..dc410b567189 100644
> --- a/arch/x86/kernel/unwind_orc.c
> +++ b/arch/x86/kernel/unwind_orc.c
> @@ -176,7 +176,7 @@ static struct orc_entry *orc_find(unsigned long ip)
> return orc_ftrace_find(ip);
> }
>
> -static void orc_sort_swap(void *_a, void *_b, int size)
> +static void orc_sort_swap(void *_a, void *_b)
> {
> struct orc_entry *orc_a, *orc_b;
> struct orc_entry orc_tmp;
> diff --git a/include/linux/sort.h b/include/linux/sort.h
> index 2b99a5dd073d..13bb4635b5f1 100644
> --- a/include/linux/sort.h
> +++ b/include/linux/sort.h
> @@ -6,6 +6,6 @@
>
> void sort(void *base, size_t num, size_t size,
> int (*cmp)(const void *, const void *),
> - void (*swap)(void *, void *, int));
> + void (*swap)(void *, void *));
>
> #endif
> diff --git a/kernel/jump_label.c b/kernel/jump_label.c
> index bad96b476eb6..6b1187b8a060 100644
> --- a/kernel/jump_label.c
> +++ b/kernel/jump_label.c
> @@ -45,7 +45,7 @@ static int jump_label_cmp(const void *a, const void *b)
> return 0;
> }
>
> -static void jump_label_swap(void *a, void *b, int size)
> +static void jump_label_swap(void *a, void *b)
> {
> long delta = (unsigned long)a - (unsigned long)b;
> struct jump_entry *jea = a;
> diff --git a/lib/extable.c b/lib/extable.c
> index f54996fdd0b8..0515a94538ca 100644
> --- a/lib/extable.c
> +++ b/lib/extable.c
> @@ -28,7 +28,7 @@ static inline unsigned long ex_to_insn(const struct exception_table_entry *x)
> #ifndef ARCH_HAS_RELATIVE_EXTABLE
> #define swap_ex NULL
> #else
> -static void swap_ex(void *a, void *b, int size)
> +static void swap_ex(void *a, void *b)
> {
> struct exception_table_entry *x = a, *y = b, tmp;
> int delta = b - a;
> diff --git a/lib/sort.c b/lib/sort.c
> index 50855ea8c262..8704750e6bde 100644
> --- a/lib/sort.c
> +++ b/lib/sort.c
> @@ -114,7 +114,7 @@ static void swap_bytes(void *a, void *b, size_t n)
> } while (n);
> }
>
> -typedef void (*swap_func_t)(void *a, void *b, int size);
> +typedef void (*swap_func_t)(void *a, void *b);
>
> /*
> * The values are arbitrary as long as they can't be confused with
> @@ -138,7 +138,7 @@ static void do_swap(void *a, void *b, size_t size, swap_func_t swap_func)
> else if (swap_func == SWAP_BYTES)
> swap_bytes(a, b, size);
> else
> - swap_func(a, b, (int)size);
> + swap_func(a, b);
> }
>
> /**
> @@ -186,8 +186,7 @@ static size_t parent(size_t i, unsigned int lsbit, size_t size)
> * it less suitable for kernel use.
> */
> void sort(void *base, size_t num, size_t size,
> - int (*cmp_func)(const void *, const void *),
> - void (*swap_func)(void *, void *, int size))
> + int (*cmp_func)(const void *, const void *), swap_func_t swap_func)
> {
> /* pre-scale counters for performance */
> size_t n = num * size, a = (num/2) * size;
> --
> 2.21.0
>
>

--
With Best Regards,
Andy Shevchenko