diff options
| author | Sebastian Andrzej Siewior <bigeasy@linutronix.de> | 2017-05-24 11:15:20 +0300 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2017-05-26 11:10:38 +0300 |
| commit | a92551e41d5a7b563ae440496bc5ca19d205231d (patch) | |
| tree | 90426918982ad1449fcae40ca3524e2e461e2f68 /drivers/cpufreq/cpufreq.c | |
| parent | 547efeadd42a3c75e41e33c0637cba100fc18289 (diff) | |
| download | linux-a92551e41d5a7b563ae440496bc5ca19d205231d.tar.xz | |
cpufreq: Use cpuhp_setup_state_nocalls_cpuslocked()
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/remove_state_nocalls_cpuslocked() to avoid the nested
call. Convert *_online_cpus() to the new interfaces while at it.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Acked-by: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: linux-pm@vger.kernel.org
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20170524081547.731628408@linutronix.de
Diffstat (limited to 'drivers/cpufreq/cpufreq.c')
| -rw-r--r-- | drivers/cpufreq/cpufreq.c | 21 |
1 files changed, 11 insertions, 10 deletions
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c index 0e3f6496524d..6001369f9aeb 100644 --- a/drivers/cpufreq/cpufreq.c +++ b/drivers/cpufreq/cpufreq.c @@ -887,7 +887,7 @@ static ssize_t store(struct kobject *kobj, struct attribute *attr, struct freq_attr *fattr = to_attr(attr); ssize_t ret = -EINVAL; - get_online_cpus(); + cpus_read_lock(); if (cpu_online(policy->cpu)) { down_write(&policy->rwsem); @@ -895,7 +895,7 @@ static ssize_t store(struct kobject *kobj, struct attribute *attr, up_write(&policy->rwsem); } - put_online_cpus(); + cpus_read_unlock(); return ret; } @@ -2441,7 +2441,7 @@ int cpufreq_register_driver(struct cpufreq_driver *driver_data) pr_debug("trying to register driver %s\n", driver_data->name); /* Protect against concurrent CPU online/offline. */ - get_online_cpus(); + cpus_read_lock(); write_lock_irqsave(&cpufreq_driver_lock, flags); if (cpufreq_driver) { @@ -2473,9 +2473,10 @@ int cpufreq_register_driver(struct cpufreq_driver *driver_data) 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_cpuslocked(CPUHP_AP_ONLINE_DYN, + "cpufreq:online", + cpuhp_cpufreq_online, + cpuhp_cpufreq_offline); if (ret < 0) goto err_if_unreg; hp_online = ret; @@ -2493,7 +2494,7 @@ err_null_driver: cpufreq_driver = NULL; write_unlock_irqrestore(&cpufreq_driver_lock, flags); out: - put_online_cpus(); + cpus_read_unlock(); return ret; } EXPORT_SYMBOL_GPL(cpufreq_register_driver); @@ -2516,17 +2517,17 @@ int cpufreq_unregister_driver(struct cpufreq_driver *driver) pr_debug("unregistering driver %s\n", driver->name); /* Protect against concurrent cpu hotplug */ - get_online_cpus(); + cpus_read_lock(); subsys_interface_unregister(&cpufreq_interface); remove_boost_sysfs_file(); - cpuhp_remove_state_nocalls(hp_online); + cpuhp_remove_state_nocalls_cpuslocked(hp_online); write_lock_irqsave(&cpufreq_driver_lock, flags); cpufreq_driver = NULL; write_unlock_irqrestore(&cpufreq_driver_lock, flags); - put_online_cpus(); + cpus_read_unlock(); return 0; } |