From 419af25fa4d0974fd758a668c08c369c19392a47 Mon Sep 17 00:00:00 2001 From: Sebastian Andrzej Siewior Date: Wed, 24 May 2017 10:15:21 +0200 Subject: [PATCH] KVM/PPC/Book3S HV: Use cpuhp_setup_state_nocalls_cpuslocked() kvmppc_alloc_host_rm_ops() holds get_online_cpus() while invoking cpuhp_setup_state_nocalls(). cpuhp_setup_state_nocalls() invokes get_online_cpus() as well. This is correct, but prevents the conversion of the hotplug locking to a percpu rwsem. Use cpuhp_setup_state_nocalls_cpuslocked() to avoid the nested call. Convert *_online_cpus() to the new interfaces while at it. Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Thomas Gleixner Acked-by: Ingo Molnar Cc: Paul E. McKenney Cc: kvm@vger.kernel.org Cc: Peter Zijlstra Cc: Benjamin Herrenschmidt Cc: Steven Rostedt Cc: kvm-ppc@vger.kernel.org Cc: Michael Ellerman Cc: linuxppc-dev@lists.ozlabs.org Cc: Alexander Graf Link: http://lkml.kernel.org/r/20170524081547.809616236@linutronix.de --- arch/powerpc/kvm/book3s_hv.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c index 42b7a4fd57d9..48a6bd160011 100644 --- a/arch/powerpc/kvm/book3s_hv.c +++ b/arch/powerpc/kvm/book3s_hv.c @@ -3317,7 +3317,7 @@ void kvmppc_alloc_host_rm_ops(void) return; } - get_online_cpus(); + cpus_read_lock(); for (cpu = 0; cpu < nr_cpu_ids; cpu += threads_per_core) { if (!cpu_online(cpu)) @@ -3339,17 +3339,17 @@ void kvmppc_alloc_host_rm_ops(void) l_ops = (unsigned long) ops; if (cmpxchg64((unsigned long *)&kvmppc_host_rm_ops_hv, 0, l_ops)) { - put_online_cpus(); + cpus_read_unlock(); kfree(ops->rm_core); kfree(ops); return; } - cpuhp_setup_state_nocalls(CPUHP_KVM_PPC_BOOK3S_PREPARE, - "ppc/kvm_book3s:prepare", - kvmppc_set_host_core, - kvmppc_clear_host_core); - put_online_cpus(); + cpuhp_setup_state_nocalls_cpuslocked(CPUHP_KVM_PPC_BOOK3S_PREPARE, + "ppc/kvm_book3s:prepare", + kvmppc_set_host_core, + kvmppc_clear_host_core); + cpus_read_unlock(); } void kvmppc_free_host_rm_ops(void) -- 2.20.1