[tip:smp/hotplug] KVM/PPC/Book3S HV: Use cpuhp_setup_state_nocalls_cpuslocked()

tip-bot for Sebastian Andrzej Siewior
2017-04-20T11:25:41Z

Commit-ID: 2fd231725b835f38e70fbda0842de57e330cd147
Gitweb: http://git.kernel.org/tip/2fd231725b835f38e70fbda0842de57e330cd147
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
AuthorDate: Tue, 18 Apr 2017 19:04:49 +0200
Committer: Thomas Gleixner <tglx@linutronix.de>
CommitDate: Thu, 20 Apr 2017 13:08:52 +0200

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.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: kvm@vger.kernel.org
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: kvm-ppc@vger.kernel.org
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: Alexander Graf <agraf@suse.com>
Link: http://lkml.kernel.org/r/20170418170552.946155801@linutronix.de

---
arch/powerpc/kvm/book3s_hv.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index 1ec86d9..df7117c 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -3336,10 +3336,10 @@ void kvmppc_alloc_host_rm_ops(void)
return;
}

- cpuhp_setup_state_nocalls(CPUHP_KVM_PPC_BOOK3S_PREPARE,
- "ppc/kvm_book3s:prepare",
- kvmppc_set_host_core,
- kvmppc_clear_host_core);
+ cpuhp_setup_state_nocalls_cpuslocked(CPUHP_KVM_PPC_BOOK3S_PREPARE,
+ "ppc/kvm_book3s:prepare",
+ kvmppc_set_host_core,
+ kvmppc_clear_host_core);
put_online_cpus();
}