Re: [PATCH v2 09/17] m68k: Implement xor_unlock_is_negative_byte

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Wed, Oct 4, 2023 at 6:53 PM Matthew Wilcox (Oracle)
<willy@xxxxxxxxxxxxx> wrote:
> Using EOR to clear the guaranteed-to-be-set lock bit will test the
> negative flag just like the x86 implementation.  This should be
> more efficient than the generic implementation in filemap.c.  It
> would be better if m68k had __GCC_ASM_FLAG_OUTPUTS__.
>
> Coldfire doesn't have a byte-sized EOR, so we test bit 7 after the
> EOR, which is a second memory access, but it's slightly better than
> the current C code.
>
> Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>

Acked-by: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx

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



[Index of Archives]     [Linux Kernel]     [Kernel Newbies]     [x86 Platform Driver]     [Netdev]     [Linux Wireless]     [Netfilter]     [Bugtraq]     [Linux Filesystems]     [Yosemite Discussion]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Samba]     [Device Mapper]

  Powered by Linux