Re: [RFC V2 05/12] cpuset: Add cpuset_inc() inside cpuset_init()

From: Mel Gorman
Date: Mon Jan 30 2017 - 15:43:58 EST

On Mon, Jan 30, 2017 at 09:05:46AM +0530, Anshuman Khandual wrote:
> Currently cpusets_enabled() wrongfully returns 0 even if we have a root
> cpuset configured on the system. This got missed when jump level was
> introduced in place of number_of_cpusets with the commit 664eeddeef65
> ("mm: page_alloc: use jump labels to avoid checking number_of_cpusets")
> . This fixes the problem so that cpusets_enabled() returns positive even
> for the root cpuset.
> Fixes: 664eeddeef65 ("mm: page_alloc: use jump labels to avoid")
> Signed-off-by: Anshuman Khandual <khandual@xxxxxxxxxxxxxxxxxx>

Superficially, this appears to always activate the cpuset_enabled
branch() when it doesn't really make sense that the root cpuset be
restricted. I strongly suspect it should be altered to cpuset_inc only
if the root cpuset is configured to isolate memory.

Mel Gorman