Messages in this thread Patch in this message |  | | Date | Sat, 15 Apr 2017 19:01:13 +0200 | From | Thomas Gleixner <> | Subject | [patch 06/20] cpufreq: Use cpuhp_setup_state_nocalls_locked() |
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From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
cpufreq holds get_online_cpus() while invoking cpuhp_setup_state_nocalls() to make subsys_interface_register() and the registration of hotplug calls atomic versus cpu hotplug.
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_locked() to avoid the nested call.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Viresh Kumar <viresh.kumar@linaro.org> Cc: linux-pm@vger.kernel.org
--- drivers/cpufreq/cpufreq.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-)
--- a/drivers/cpufreq/cpufreq.c +++ b/drivers/cpufreq/cpufreq.c @@ -2473,9 +2473,10 @@ int cpufreq_register_driver(struct cpufr goto err_if_unreg; } - ret = cpuhp_setup_state_nocalls(CPUHP_AP_ONLINE_DYN, "cpufreq:online", - cpuhp_cpufreq_online, - cpuhp_cpufreq_offline); + ret = cpuhp_setup_state_nocalls_locked(CPUHP_AP_ONLINE_DYN, + "cpufreq:online", + cpuhp_cpufreq_online, + cpuhp_cpufreq_offline); if (ret < 0) goto err_if_unreg; hp_online = ret; @@ -2519,7 +2520,7 @@ int cpufreq_unregister_driver(struct cpu get_online_cpus(); subsys_interface_unregister(&cpufreq_interface); remove_boost_sysfs_file(); - cpuhp_remove_state_nocalls(hp_online); + cpuhp_remove_state_nocalls_locked(hp_online); write_lock_irqsave(&cpufreq_driver_lock, flags);
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