Re: [PATCH 6/6] Use one zonelist that is filtered by nodemask

Lee Schermerhorn
2007-10-10T15:53:43Z

On Tue, 2007-10-09 at 16:40 +0100, Mel Gorman wrote:
<snip>
> ====
> Subject: Use specified node ID with GFP_THISNODE if available
>
> It had been assumed that __GFP_THISNODE meant allocating from the local
> node and only the local node. However, users of alloc_pages_node() may also
> specify GFP_THISNODE. In this case, only the specified node should be used.
> This patch will allocate pages only from the requested node when GFP_THISNODE
> is used with alloc_pages_node().
>
> [nacc@us.ibm.com: Detailed analysis of problem]
> Found-by: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
> Signed-off-by: Mel Gorman <mel@csn.ul.ie>
>
<snip>

Mel: I applied this patch [to your v8 series--the most recent, I
think?] and it does fix the problem. However, now I'm tripping over
this warning in __alloc_pages_nodemask:

/* Specifying both __GFP_THISNODE and nodemask is stupid. Warn user */
WARN_ON(gfp_mask & __GFP_THISNODE);

for each huge page allocated. Rather slow as my console is a virtual
serial line and the warning includes the stack traceback.

I think we want to just drop this warning, but maybe you have a tighter
condition that you want to warn about?

Lee