Re: [PATCH v7 3/5] mm/hugetlb: add support for mempolicy MPOL_PREFERRED_MANY

[Feng Tang]

Hi Michal,

Thanks for the review and ACKs to 1/5 and 2/5 patches.

On Fri, Aug 06, 2021 at 03:35:48PM +0200, Michal Hocko wrote:
> On Tue 03-08-21 13:59:20, Feng Tang wrote:
> > From: Ben Widawsky <ben.widawsky@xxxxxxxxx>
> > 
> > Implement the missing huge page allocation functionality while obeying
> > the preferred node semantics. This is similar to the implementation
> > for general page allocation, as it uses a fallback mechanism to try
> > multiple preferred nodes first, and then all other nodes.
> > 
> > [akpm: fix compling issue when merging with other hugetlb patch]
> > [Thanks to 0day bot for catching the missing #ifdef CONFIG_NUMA issue]
> > Link: https://lore.kernel.org/r/20200630212517.308045-12-ben.widawsky@xxxxxxxxx
> > Suggested-by: Michal Hocko <mhocko@xxxxxxxx>
> > Signed-off-by: Ben Widawsky <ben.widawsky@xxxxxxxxx>
> > Co-developed-by: Feng Tang <feng.tang@xxxxxxxxx>
> > Signed-off-by: Feng Tang <feng.tang@xxxxxxxxx>
> 
> ifdefery is just ugly as hell. One way to get rid of that would be to
> provide a mpol_is_preferred_many() wrapper and hide the CONFIG_NUMA in
> mempolicy.h. I haven't checked but this might help to remove some other
> ifdefery as well.
> 
> I especially dislike the label hidden in the ifdef. You can get rid of
> that by checking the page for NULL.

Yes, the 'ifdef's were annoying to me too, and thanks for the suggestions.
Following is the revised patch upon the suggestion.

Thanks,
Feng

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