Re: [PATCH v2] hugetlbfs: correct handling of negative input to /proc/sys/vm/nr_hugepages

Andrew Morton
2011-02-24T22:14:17Z

On Thu, 24 Feb 2011 14:10:34 -0800
Andrew Morton <akpm@linux-foundation.org> wrote:

> On Tue, 22 Feb 2011 21:17:04 +0100
> Petr Holasek <pholasek@redhat.com> wrote:
>
> > When user insert negative value into /proc/sys/vm/nr_hugepages it will
> > result
> > in the setting a random number of HugePages in system
>
> Is this true? afacit the kernel will allocate as many pages as it can
> and will then set /proc/sys/vm/nr_hugepages to reflect the result.
> That's not random.
>

Assuming the above to be correct, I altered the changelog thusly:

: When the user inserts a negative value into /proc/sys/vm/nr_hugepages it
: will cause the kernel to allocate as many hugepages as possible and to
: then update /proc/meminfo to reflect this.
:
: This changes the behavior so that the negative input will result in
: nr_hugepages value being unchanged.

and given that, I don't really see why we should change the existing behaviour.