2023-11-18 15:55:24

by Yury Norov

Subject: [PATCH 32/34] m68k: rework get_mmu_context()

ALSA code opencodes atomic find_and_set_bit_wrap(). Switch it to
dedicated function.

Signed-off-by: Yury Norov <[email protected]>
---
arch/m68k/include/asm/mmu_context.h | 11 +++++------
1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/arch/m68k/include/asm/mmu_context.h b/arch/m68k/include/asm/mmu_context.h
index 141bbdfad960..0419ad87a1c1 100644
--- a/arch/m68k/include/asm/mmu_context.h
+++ b/arch/m68k/include/asm/mmu_context.h
@@ -35,12 +35,11 @@ static inline void get_mmu_context(struct mm_struct *mm)
atomic_inc(&nr_free_contexts);
steal_context();
}
- ctx = next_mmu_context;
- while (test_and_set_bit(ctx, context_map)) {
- ctx = find_next_zero_bit(context_map, LAST_CONTEXT+1, ctx);
- if (ctx > LAST_CONTEXT)
- ctx = 0;
- }
+
+ do {
+ ctx = find_and_set_bit_wrap(context_map, LAST_CONTEXT + 1, next_mmu_context);
+ } while (ctx > LAST_CONTEXT);
+
next_mmu_context = (ctx + 1) & LAST_CONTEXT;
mm->context = ctx;
context_mm[ctx] = mm;
--
2.39.2

2023-11-19 19:29:40

by Geert Uytterhoeven

Subject: Re: [PATCH 32/34] m68k: rework get_mmu_context()

Hi Yuri,

Thanks for your patch!

On Sat, Nov 18, 2023 at 4:51 PM Yury Norov <[email protected]> wrote:
> ALSA code opencodes atomic find_and_set_bit_wrap(). Switch it to

ALSA?

> dedicated function.
>
> Signed-off-by: Yury Norov <[email protected]>

The rest LGTM, but as it's Coldfire code, I'd like to defer to Greg.

Gr{oetje,eeting}s,

Geert


--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- [email protected]

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds

2023-11-21 14:39:33

by Greg Ungerer

Subject: Re: [PATCH 32/34] m68k: rework get_mmu_context()

Hi Yury,

On 19/11/23 01:51, Yury Norov wrote:
> ALSA code opencodes atomic find_and_set_bit_wrap(). Switch it to
^^^^
m68k?


> dedicated function.
>
> Signed-off-by: Yury Norov <[email protected]>

Looks ok to me:

Acked-by: Greg Ungerer <[email protected]>

Regards
Greg



> ---
> arch/m68k/include/asm/mmu_context.h | 11 +++++------
> 1 file changed, 5 insertions(+), 6 deletions(-)
>
> diff --git a/arch/m68k/include/asm/mmu_context.h b/arch/m68k/include/asm/mmu_context.h
> index 141bbdfad960..0419ad87a1c1 100644
> --- a/arch/m68k/include/asm/mmu_context.h
> +++ b/arch/m68k/include/asm/mmu_context.h
> @@ -35,12 +35,11 @@ static inline void get_mmu_context(struct mm_struct *mm)
> atomic_inc(&nr_free_contexts);
> steal_context();
> }
> - ctx = next_mmu_context;
> - while (test_and_set_bit(ctx, context_map)) {
> - ctx = find_next_zero_bit(context_map, LAST_CONTEXT+1, ctx);
> - if (ctx > LAST_CONTEXT)
> - ctx = 0;
> - }
> +
> + do {
> + ctx = find_and_set_bit_wrap(context_map, LAST_CONTEXT + 1, next_mmu_context);
> + } while (ctx > LAST_CONTEXT);
> +
> next_mmu_context = (ctx + 1) & LAST_CONTEXT;
> mm->context = ctx;
> context_mm[ctx] = mm;