Re: [dpdk-dev] [dpdk-stable] [PATCH v2] eal: change max hugepage sizes to 4 for ARM platforms

[David Marchand <david.marchand@redhat.com>]

On Thu, Aug 8, 2019 at 2:27 PM Gagandeep Singh <g.singh@nxp.com> wrote:
>
> ARM is supporting maximum 4 hugepage sizes (64K, 2M, 32M
> and 1G) when granule is 4KB since very long and DPDK
> support maximum 3 hugepage sizes.
>
> With all 4 hugepage sizes enabled, applications and some
> stacks like VPP which are working over DPDK and using
> "in-memory" eal option, or using separate mount points
> on ARM based platform, fails at huge page initialization,
> reporting error messages from eal:
>
> EAL: FATAL: Cannot get hugepage information.
> EAL: Cannot get hugepage information.
> EAL: Error - exiting with code: 1
>
> This issue is visible on kernel 5.2 (stable rel), where
> kernel is by default creating directories for each supported
> hugepage size in /sys/kernel/mm/hugepages/

Yes, any supported hugepage size is announced in sysfs.

> On earlier Stable Kernel LTR's, the directories visible in
> /sys/kernel/mm/hugepages/ were dependent upon what hugepage
> sizes are configured at boot time.

The change is in kernel 5.0 with:
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=a21b0b78

where all supported sizes are now registered.

>
> This change increases the maximum supported mount points
> to 4 for ARM based platforms.
>
> Cc: stable@dpdk.org
>
> Signed-off-by: Gagandeep Singh <g.singh@nxp.com>
> Signed-off-by: Nipun Gupta <nipun.gupta@nxp.com>
> ---
>
> Changes in V2:
>  - restricted this change specific to ARM
>  - commit message updated
>  - stable added to cc


Please keep me Cc:.


-- 
David Marchand