[patch 10/20] perf/x86/intel/cqm: Use cpuhp_setup_state_locked()

[Thomas Gleixner]

From: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>

intel_cqm_init() holds get_online_cpus() while registerring the hotplug
callbacks.

cpuhp_setup_state() 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_locked() to avoid the nested call.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: x86@xxxxxxxxxx
Cc: Fenghua Yu <fenghua.yu@xxxxxxxxx>

---
 arch/x86/events/intel/cqm.c |   12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

--- a/arch/x86/events/intel/cqm.c
+++ b/arch/x86/events/intel/cqm.c
@@ -1746,12 +1746,12 @@ static int __init intel_cqm_init(void)
 	 * Setup the hot cpu notifier once we are sure cqm
 	 * is enabled to avoid notifier leak.
 	 */
-	cpuhp_setup_state(CPUHP_AP_PERF_X86_CQM_STARTING,
-			  "perf/x86/cqm:starting",
-			  intel_cqm_cpu_starting, NULL);
-	cpuhp_setup_state(CPUHP_AP_PERF_X86_CQM_ONLINE, "perf/x86/cqm:online",
-			  NULL, intel_cqm_cpu_exit);
-
+	cpuhp_setup_state_locked(CPUHP_AP_PERF_X86_CQM_STARTING,
+				 "perf/x86/cqm:starting",
+				 intel_cqm_cpu_starting, NULL);
+	cpuhp_setup_state_locked(CPUHP_AP_PERF_X86_CQM_ONLINE,
+				 "perf/x86/cqm:online",
+				 NULL, intel_cqm_cpu_exit);
 out:
 	put_online_cpus();