Dave Hansen brought this to my attention.  I've attached the bit of the 
memory fragmentation avoidance you conflict with (I'm working with Mel 
on his patches).  I think we share similar goals, and I wouldn't mind 
changing __GFP_USERRCLM to __GFP_USERALLOC or some neutral name we could 
share.  Anything to increase the chances of fragmentation avoidance 
getting merged is good in my book.

-Joel


>>GFP_USER allocations, and distinguish them from GFP_KERNEL allocations.
>>
>>Allocations (such as GFP_USER) marked GFP_HARDWALL are constrainted to
>>the current tasks cpuset.  Other allocations (such as GFP_KERNEL) can
>>steal from the possibly larger nearest mem_exclusive cpuset ancestor,
>>if memory is tight on every node in the current cpuset.
>>
>>This patch collides with Mel Gorman's patch to reduce fragmentation
>>in the standard buddy allocator, which adds two GFP flags.  At first
>>glance, it seems that his added __GFP_USERRCLM flag could be used in
>>place of the following __GFP_HARDWALL, as they both seem to be set
>>the same way - for GFP_USER and GFP_HIGHUSER.  Perhaps we should call
>>this flag __GFP_USER, rather than some name dependent on its use(s).
> 
> 
> Does this make sense to integrate into your patches?
> 
> Index: linux-2.6-mem_exclusive/include/linux/gfp.h
> ===================================================================
> --- linux-2.6-mem_exclusive.orig/include/linux/gfp.h	2005-07-02 17:42:02.000000000 -0700
> +++ linux-2.6-mem_exclusive/include/linux/gfp.h	2005-07-02 17:43:00.000000000 -0700
> @@ -40,6 +40,7 @@ struct vm_area_struct;
>  #define __GFP_ZERO	0x8000u	/* Return zeroed page on success */
>  #define __GFP_NOMEMALLOC 0x10000u /* Don't use emergency reserves */
>  #define __GFP_NORECLAIM  0x20000u /* No zone reclaim during page_cache_alloc */
> +#define __GFP_HARDWALL   0x40000u /* Enforce hardwall cpuset memory allocs */
>  
>  #define __GFP_BITS_SHIFT 20	/* Room for 20 __GFP_FOO bits */
>  #define __GFP_BITS_MASK ((1 << __GFP_BITS_SHIFT) - 1)
> @@ -48,14 +49,15 @@ struct vm_area_struct;
>  #define GFP_LEVEL_MASK (__GFP_WAIT|__GFP_HIGH|__GFP_IO|__GFP_FS| \
>  			__GFP_COLD|__GFP_NOWARN|__GFP_REPEAT| \
>  			__GFP_NOFAIL|__GFP_NORETRY|__GFP_NO_GROW|__GFP_COMP| \
> -			__GFP_NOMEMALLOC|__GFP_NORECLAIM)
> +			__GFP_NOMEMALLOC|__GFP_NORECLAIM|__GFP_HARDWALL)
>  
>  #define GFP_ATOMIC	(__GFP_HIGH)
>  #define GFP_NOIO	(__GFP_WAIT)
>  #define GFP_NOFS	(__GFP_WAIT | __GFP_IO)
>  #define GFP_KERNEL	(__GFP_WAIT | __GFP_IO | __GFP_FS)
> -#define GFP_USER	(__GFP_WAIT | __GFP_IO | __GFP_FS)
> -#define GFP_HIGHUSER	(__GFP_WAIT | __GFP_IO | __GFP_FS | __GFP_HIGHMEM)
> +#define GFP_USER	(__GFP_WAIT | __GFP_IO | __GFP_FS | __GFP_HARDWALL)
> +#define GFP_HIGHUSER	(__GFP_WAIT | __GFP_IO | __GFP_FS | __GFP_HARDWALL | \
> +			 __GFP_HIGHMEM)
>  
>  /* Flag - indicates that the buffer will be suitable for DMA.  Ignored on some
>     platforms, used as appropriate on others */