[PATCH] powerpc/mobility: Extend start/stop topology update scope

[Michael Ellerman]

Michael Bringmann <mwb at linux.vnet.ibm.com> writes:

> The PPC mobility code may receive RTAS requests to perform PRRN
> topology changes at any time, including during LPAR migration
> operations.  In some configurations where the affinity of CPUs
> or memory is being changed on that platform, the PRRN requests
> may apply or refer to outdated information prior to the complete
> update of the device-tree.  This patch changes the duration for
> which topology updates are suppressed during LPAR migrations from
> just the rtas_ibm_suspend_me / 'ibm,suspend-me' call(s) to cover
> the entire 'migration_store' operation to allow all changes to
> the device-tree to be applied prior to accepting and applying any
> PRRN requests.
>
> For tracking purposes, pr_info notices are added to the functions
> start_topology_update() and stop_topology_update() of 'numa.c'.
>
> Signed-off-by: Michael Bringmann <mwb at linux.vnet.ibm.com>
> ---
>  arch/powerpc/kernel/rtas.c                |    4 ----
>  arch/powerpc/mm/numa.c                    |    6 ++++++
>  arch/powerpc/platforms/pseries/mobility.c |    5 +++++
>  3 files changed, 11 insertions(+), 4 deletions(-)
>
> diff --git a/arch/powerpc/kernel/rtas.c b/arch/powerpc/kernel/rtas.c
> index 8afd146..28d8b57 100644
> --- a/arch/powerpc/kernel/rtas.c
> +++ b/arch/powerpc/kernel/rtas.c
> @@ -981,8 +981,6 @@ int rtas_ibm_suspend_me(u64 handle)
>  		goto out;
>  	}
>  
> -	stop_topology_update();
> -
>  	/* Call function on all CPUs.  One of us will make the
>  	 * rtas call
>  	 */

This doesn't apply to my next branch, it conflicts with:

  85a88cabad57 ("powerpc/pseries: Disable CPU hotplug across migrations")

Can you please rebase it?

https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git/log/?h=next

cheers