From b8e6a87c82927ed9ccf0f3ee42946a41cb9d75fe Mon Sep 17 00:00:00 2001 From: Suresh Warrier Date: Thu, 17 Dec 2015 14:59:07 -0600 Subject: [PATCH] KVM: PPC: Book3S HV: Manage core host state Update the core host state in kvmppc_host_rm_ops whenever the primary thread of the core enters the guest or returns back. Signed-off-by: Suresh Warrier Signed-off-by: Paul Mackerras --- arch/powerpc/kvm/book3s_hv.c | 44 ++++++++++++++++++++++++++++++++++++ 1 file changed, 44 insertions(+) diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c index 8b3332fb9ed2..542ec97129b4 100644 --- a/arch/powerpc/kvm/book3s_hv.c +++ b/arch/powerpc/kvm/book3s_hv.c @@ -2302,6 +2302,46 @@ static void post_guest_process(struct kvmppc_vcore *vc, bool is_master) spin_unlock(&vc->lock); } +/* + * Clear core from the list of active host cores as we are about to + * enter the guest. Only do this if it is the primary thread of the + * core (not if a subcore) that is entering the guest. + */ +static inline void kvmppc_clear_host_core(int cpu) +{ + int core; + + if (!kvmppc_host_rm_ops_hv || cpu_thread_in_core(cpu)) + return; + /* + * Memory barrier can be omitted here as we will do a smp_wmb() + * later in kvmppc_start_thread and we need ensure that state is + * visible to other CPUs only after we enter guest. + */ + core = cpu >> threads_shift; + kvmppc_host_rm_ops_hv->rm_core[core].rm_state.in_host = 0; +} + +/* + * Advertise this core as an active host core since we exited the guest + * Only need to do this if it is the primary thread of the core that is + * exiting. + */ +static inline void kvmppc_set_host_core(int cpu) +{ + int core; + + if (!kvmppc_host_rm_ops_hv || cpu_thread_in_core(cpu)) + return; + + /* + * Memory barrier can be omitted here because we do a spin_unlock + * immediately after this which provides the memory barrier. + */ + core = cpu >> threads_shift; + kvmppc_host_rm_ops_hv->rm_core[core].rm_state.in_host = 1; +} + /* * Run a set of guest threads on a physical core. * Called with vc->lock held. @@ -2414,6 +2454,8 @@ static noinline void kvmppc_run_core(struct kvmppc_vcore *vc) } } + kvmppc_clear_host_core(pcpu); + /* Start all the threads */ active = 0; for (sub = 0; sub < core_info.n_subcores; ++sub) { @@ -2510,6 +2552,8 @@ static noinline void kvmppc_run_core(struct kvmppc_vcore *vc) kvmppc_ipi_thread(pcpu + i); } + kvmppc_set_host_core(pcpu); + spin_unlock(&vc->lock); /* make sure updates to secondary vcpu structs are visible now */ -- 2.20.1