lkml.org 
[lkml]   [2006]   [Jan]   [5]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
SubjectRe: [Patch] New zone ZONE_EASY_RECLAIM take 4. (change build_zonelists)[3/8]
> > -	BUG_ON(zone_type > ZONE_HIGHMEM);
> > + BUG_ON(zone_type > ZONE_EASY_RECLAIM);
>
> It might be nice to check ifndef CONFIG_HIGHMEM that the zone isn't
> particularly ZONE_HIGHMEM.

Hmm. I was a bit lazy :-(.

> > int res = ZONE_NORMAL;
> > - if (zone_bits & (__force int)__GFP_HIGHMEM)
> > - res = ZONE_HIGHMEM;
> > - if (zone_bits & (__force int)__GFP_DMA32)
> > - res = ZONE_DMA32;
> > - if (zone_bits & (__force int)__GFP_DMA)
> > +
> > + if (zone_bits == fls((__force int)__GFP_DMA))
> > res = ZONE_DMA;
> > + if (zone_bits == fls((__force int)__GFP_DMA32) &&
> > + (__force int)__GFP_DMA32 == 0x02)
> > + res = ZONE_DMA32;
> > + if (zone_bits == fls((__force int)__GFP_HIGHMEM))
> > + res = ZONE_HIGHMEM;
> > + if (zone_bits == fls((__force int)__GFP_EASY_RECLAIM))
> > + res = ZONE_EASY_RECLAIM;
> > +
> > return res;
> > }
>
> It is incredibly silly to check a constant for a value. When it is zero
> instead of 2 the first part of the statement will be false anyway.
> Which reminds me. Why are we using fls again? I don't see why we
> aren't just (zone_bits & value) the types. It seems much easier to
> understand that way.

Ahhh. I might be still confused around it. :-(
Its cause came from the value of __GFP_DMA32 which might be 0, 1, or 2.
This was that I tried to solve making zonelists for all of them.
But, something looks redundant.....

Thanks.


>
> >
> > Index: zone_reclaim/include/linux/gfp.h
> > ===================================================================
> > --- zone_reclaim.orig/include/linux/gfp.h 2005-12-19 20:19:37.000000000 +0900
> > +++ zone_reclaim/include/linux/gfp.h 2005-12-19 20:19:56.000000000 +0900
> > @@ -81,7 +81,7 @@ struct vm_area_struct;
> >
> > static inline int gfp_zone(gfp_t gfp)
> > {
> > - int zone = GFP_ZONEMASK & (__force int) gfp;
> > + int zone = fls(GFP_ZONEMASK & (__force int) gfp);
> > BUG_ON(zone >= GFP_ZONETYPES);
> > return zone;
> > }
> >
>
>

--
Yasunori Goto


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

\
 
 \ /
  Last update: 2006-01-05 06:45    [W:0.059 / U:0.368 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site