[v3, 1/4] KVM: PPC: Book3S HV: POWER9 does not require secondary thread management

Michael Ellerman patch-notifications at ellerman.id.au
Thu Aug 31 21:36:17 AEST 2017


On Fri, 2017-08-25 at 04:30:33 UTC, Nicholas Piggin wrote:
> POWER9 CPUs have independent MMU contexts per thread, so KVM does not
> need to quiesce secondary threads, so the hwthread_req/hwthread_state
> protocol does not have to be used. So patch it away on POWER9, and patch
> away the branch from the Linux idle wakeup to kvm_start_guest that is
> never used.
> 
> Add a warning and error out of kvmppc_grab_hwthread in case it is ever
> called on POWER9.
> 
> This avoids a hwsync in the idle wakeup path on POWER9.
> 
> Signed-off-by: Nicholas Piggin <npiggin at gmail.com>
> Acked-by: Paul Mackerras <paulus at ozlabs.org>

Applied to powerpc next, thanks.

https://git.kernel.org/powerpc/c/94a04bc25a2c6296bd0c5e82c10e82

cheers


More information about the Linuxppc-dev mailing list