Re: Question about Zone Allocation 2.4.X

From: Jeff V. Merkey (jmerkey@vger.timpanogas.org)
Date: Thu Jan 02 2003 - 20:15:54 EST


On Thu, Jan 02, 2003 at 04:00:34PM -0800, William Lee Irwin III wrote:
> At some point in the past, I wrote:
> >> __get_free_pages() allocates from lowmem (i.e. 0-4GB) only.
> >> Allocate from highmem instead.
>
> 0-1GB. page_address() will give unpredictable results on highmem GFP masks.

Sounds broken to me.

>
> There is no GFP mask for it. Port Jens' ZONE_DMA32 or something, or roll
> ZONE_4G on your own if need be.

Bill,

Looks like we simply jetisioned the concept of a PPL (Physical Pages List)
and went with a zone allocator instead. I'm sure there was a good reason for
it historically. Rolling a separate zone is exactly what I was thinking
when I reviewed the code intially. Question, which files will be affected so when I put this one in, I don't end up breaking the VM and userspace balancing
logic. i.e. Could you point me to Jens' ZONE_DMA32 code as well.

Thanks

Jeff

>
>
> Bill

-
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/



This archive was generated by hypermail 2b29 : Tue Jan 07 2003 - 22:00:19 EST