From 441c19c8a290f5f1e1b263691641124c84232b6e Mon Sep 17 00:00:00 2001 From: Michael Ellerman Date: Fri, 23 May 2014 18:15:25 +1000 Subject: powerpc/kvm/book3s_hv: Rework the secondary inhibit code As part of the support for split core on POWER8, we want to be able to block splitting of the core while KVM VMs are active. The logic to do that would be exactly the same as the code we currently have for inhibiting onlining of secondaries. Instead of adding an identical mechanism to block split core, rework the secondary inhibit code to be a "HV KVM is active" check. We can then use that in both the cpu hotplug code and the upcoming split core code. Signed-off-by: Michael Ellerman Signed-off-by: Michael Neuling Acked-by: Alexander Graf Acked-by: Paul Mackerras Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/kernel/smp.c | 34 +++------------------------------- 1 file changed, 3 insertions(+), 31 deletions(-) (limited to 'arch/powerpc/kernel') diff --git a/arch/powerpc/kernel/smp.c b/arch/powerpc/kernel/smp.c index 4863ea14f270..5cdd9eb3b24c 100644 --- a/arch/powerpc/kernel/smp.c +++ b/arch/powerpc/kernel/smp.c @@ -36,6 +36,7 @@ #include #include #include +#include #include #include #include @@ -458,38 +459,9 @@ int generic_check_cpu_restart(unsigned int cpu) return per_cpu(cpu_state, cpu) == CPU_UP_PREPARE; } -static atomic_t secondary_inhibit_count; - -/* - * Don't allow secondary CPU threads to come online - */ -void inhibit_secondary_onlining(void) -{ - /* - * This makes secondary_inhibit_count stable during cpu - * online/offline operations. - */ - get_online_cpus(); - - atomic_inc(&secondary_inhibit_count); - put_online_cpus(); -} -EXPORT_SYMBOL_GPL(inhibit_secondary_onlining); - -/* - * Allow secondary CPU threads to come online again - */ -void uninhibit_secondary_onlining(void) -{ - get_online_cpus(); - atomic_dec(&secondary_inhibit_count); - put_online_cpus(); -} -EXPORT_SYMBOL_GPL(uninhibit_secondary_onlining); - -static int secondaries_inhibited(void) +static bool secondaries_inhibited(void) { - return atomic_read(&secondary_inhibit_count); + return kvm_hv_mode_active(); } #else /* HOTPLUG_CPU */ -- cgit