[LTP] [PATCH v2] move_pages12: Make sure hugepages are available

[Jan Stancek <jstancek@redhat.com>]

----- Original Message -----
> 
> 
> ----- Original Message -----
> > Hi!
> > > "hugepages-2048kB" in path above will work only on systems with 2M huge
> > > pages.
> > 
> > Do you have a ppc64 numa machine with more than two nodes at hand? Since
> 
> Yes, I have access to couple with 4 numa nodes.
> 
> > that is the only one where the current code may fail. Both x86_64 and
> > aarch64 seems to have 2MB huge pages.
> 
> Default huge page for aarch64 is 512M.
> 
> # cat /proc/meminfo | grep Hugepagesize
> Hugepagesize:     524288 kB
> 
> # uname -r
> 4.11.0-2.el7.aarch64
> 
> I think in 4.11 you can't even switch with default_hugepagesz=2M at the
> moment:
>  6ae979ab39a3 "Revert "Revert "arm64: hugetlb: partial revert of
>  66b3923a1a0f"""
> 
> > 
> > I would just go with this patch now, and possibly fix more complicated
> > corner cases after the release, since this patch is the last problem
> > that holds the release from my side.
> 
> Can't we squeeze it in? All we need is to use "hpsz" we already have:
> 
>   snprintf(path_hugepages_node1, sizeof(path_hugepages_node1),
>           "/sys/devices/system/node/node%u/hugepages/hugepages-%dkB/nr_hugepages",
>           node1, hpsz);

Correction: "hpsz / 1024", we multiply it in setup() by 1024.