KVM: PPC: Book3S HV: Call kvmppc_handle_exit_hv() with vcore unlocked
authorPaul Mackerras <paulus@ozlabs.org>
Mon, 8 Oct 2018 05:30:54 +0000 (16:30 +1100)
committerMichael Ellerman <mpe@ellerman.id.au>
Tue, 9 Oct 2018 05:04:27 +0000 (16:04 +1100)
commit53655ddd7771f703071ac81cc5823eae509b6653
tree6e2d612098d8b5114035e352dd3b4d4f0e900a8a
parent7854f7545bff69567fc3fcd8831752138b892483
KVM: PPC: Book3S HV: Call kvmppc_handle_exit_hv() with vcore unlocked

Currently kvmppc_handle_exit_hv() is called with the vcore lock held
because it is called within a for_each_runnable_thread loop.
However, we already unlock the vcore within kvmppc_handle_exit_hv()
under certain circumstances, and this is safe because (a) any vcpus
that become runnable and are added to the runnable set by
kvmppc_run_vcpu() have their vcpu->arch.trap == 0 and can't actually
run in the guest (because the vcore state is VCORE_EXITING), and
(b) for_each_runnable_thread is safe against addition or removal
of vcpus from the runnable set.

Therefore, in order to simplify things for following patches, let's
drop the vcore lock in the for_each_runnable_thread loop, so
kvmppc_handle_exit_hv() gets called without the vcore lock held.

Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
arch/powerpc/kvm/book3s_hv.c