linux-kernel - Re: [patch 3/6] fbdev: c2p

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Mon, 22 Dec 2008 15:22:06 -0800
From:	Andrew Morton <akpm@...ux-foundation.org>
To:	Geert Uytterhoeven <geert@...ux-m68k.org>
Cc:	schmitz@...l.biophys.uni-duesseldorf.de,
	linux-fbdev-devel@...ts.sourceforge.net,
	linux-m68k@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [patch 3/6] fbdev: c2p - Cleanups

On Sun, 21 Dec 2008 16:01:02 +0100
Geert Uytterhoeven <geert@...ux-m68k.org> wrote:

>   - Improve comments and naming
>   - Use void * for arbitrary pointers
>   - Use a union to represent pixels/words, to avoid casts
> 
> Signed-off-by: Geert Uytterhoeven <geert@...ux-m68k.org>
> ---
>  drivers/video/c2p.c |   80 +++++++++++++++++++++++++++-------------------------
>  drivers/video/c2p.h |    6 +--
>  2 files changed, 45 insertions(+), 41 deletions(-)
> 
> --- a/drivers/video/c2p.c
> +++ b/drivers/video/c2p.c
> @@ -54,7 +54,7 @@ static inline u32 get_mask(int n)
>      return 0;
>  }
>  
> -#define transp_nx1(d, n)				\
> +#define transp8_nx1(d, n)				\
>      do {						\
>  	u32 mask = get_mask(n);				\
>  	/* First block */				\
> @@ -67,7 +67,7 @@ static inline u32 get_mask(int n)
>  	_transp(d, 6, 7, n, mask);			\
>      } while (0)
> -#define transp_nx2(d, n)				\
> +#define transp8_nx2(d, n)				\
>      do {						\
>  	u32 mask = get_mask(n);				\
>  	/* First block */				\
> @@ -78,40 +78,41 @@ static inline u32 get_mask(int n)

I was going to say:

- these don't need to be implemented as macros

- these reference their arguments multiple times and will cause
  problems when passed an expression with side-effects.

- they should be converted to inlined C function, but those functions
  will be waaaaaaaay to big to inline.

but happily, they appear to not have any callers?

>  	_transp(d, 5, 7, n, mask);			\
>      } while (0)
>  
> -#define transp_nx4(d, n)				\
> +#define transp8_nx4(d, n)				\
>      do {						\
>  	u32 mask = get_mask(n);				\
> +	/* Single block */				\
>  	_transp(d, 0, 4, n, mask);			\
>  	_transp(d, 1, 5, n, mask);			\
>  	_transp(d, 2, 6, n, mask);			\
>  	_transp(d, 3, 7, n, mask);			\
>      } while (0)
>  
> -#define transp(d, n, m)	transp_nx ## m(d, n)
> +#define transp8(d, n, m)	transp8_nx ## m(d, n)

ah, yes they do.  Tricky!

>  
>      /*
> @@ -130,12 +131,12 @@ static inline unsigned long comp(unsigne
>       *  Store a full block of planar data after c2p conversion
>       */
>  
> -static inline void store_planar(char *dst, u32 dst_inc, u32 bpp, u32 d[8])
> +static inline void store_planar(void *dst, u32 dst_inc, u32 bpp, u32 d[8])
>  {
>      int i;
>  
>      for (i = 0; i < bpp; i++, dst += dst_inc)
> -	*(u32 *)dst = d[perm_c2p_8bpp[i]];
> +	*(u32 *)dst = d[perm_c2p_32x8[i]];
>  }
>  
>  
> @@ -143,13 +144,13 @@ static inline void store_planar(char *ds
>       *  Store a partial block of planar data after c2p conversion
>       */
>  
> -static inline void store_planar_masked(char *dst, u32 dst_inc, u32 bpp,
> +static inline void store_planar_masked(void *dst, u32 dst_inc, u32 bpp,
>  				       u32 d[8], u32 mask)
>  {
>      int i;
>  
>      for (i = 0; i < bpp; i++, dst += dst_inc)
> -	*(u32 *)dst = comp(d[perm_c2p_8bpp[i]], *(u32 *)dst, mask);
> +	*(u32 *)dst = comp(d[perm_c2p_32x8[i]], *(u32 *)dst, mask);
>  }

This driver needs a inlineectomy.


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/