From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1032305AbdEXI3Y (ORCPT ); Wed, 24 May 2017 04:29:24 -0400 Received: from Galois.linutronix.de ([146.0.238.70]:58042 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1765495AbdEXI01 (ORCPT ); Wed, 24 May 2017 04:26:27 -0400 Message-Id: <20170524081547.809616236@linutronix.de> User-Agent: quilt/0.63-1 Date: Wed, 24 May 2017 10:15:21 +0200 From: Thomas Gleixner To: LKML Cc: Peter Zijlstra , Ingo Molnar , Steven Rostedt , Sebastian Siewior , Paul McKenney , kvm@vger.kernel.org, Benjamin Herrenschmidt , kvm-ppc@vger.kernel.org, Michael Ellerman , linuxppc-dev@lists.ozlabs.org, Alexander Graf Subject: [patch V3 10/32] KVM/PPC/Book3S HV: Use cpuhp_setup_state_nocalls_cpuslocked() References: <20170524081511.203800767@linutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Content-Disposition: inline; filename=KVMPPCBook3S_HV_Use_cpuhp_setup_state_nocalls_cpuslocked().patch Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Sebastian Andrzej Siewior 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 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 --- arch/powerpc/kvm/book3s_hv.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) --- 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)