From 7b7139d4abe8a94446db6a91882f1400920891d5 Mon Sep 17 00:00:00 2001 From: "Srivatsa S. Bhat" Date: Tue, 11 Mar 2014 02:07:28 +0530 Subject: [PATCH] x86, therm_throt.c: Remove unused therm_cpu_lock After fixing the CPU hotplug callback registration code, the callbacks invoked for each online CPU, during the initialization phase in thermal_throttle_init_device(), can no longer race with the actual CPU hotplug notifier callbacks (in thermal_throttle_cpu_callback). Hence the therm_cpu_lock is unnecessary now. Remove it. Cc: Tony Luck Cc: Borislav Petkov Cc: Thomas Gleixner Cc: Ingo Molnar Cc: "H. Peter Anvin" Suggested-by: Oleg Nesterov Signed-off-by: Srivatsa S. Bhat Signed-off-by: Rafael J. Wysocki --- arch/x86/kernel/cpu/mcheck/therm_throt.c | 13 ------------- 1 file changed, 13 deletions(-) diff --git a/arch/x86/kernel/cpu/mcheck/therm_throt.c b/arch/x86/kernel/cpu/mcheck/therm_throt.c index e05dfa398dc2..d921b7ee6595 100644 --- a/arch/x86/kernel/cpu/mcheck/therm_throt.c +++ b/arch/x86/kernel/cpu/mcheck/therm_throt.c @@ -271,9 +271,6 @@ static void thermal_throttle_remove_dev(struct device *dev) sysfs_remove_group(&dev->kobj, &thermal_attr_group); } -/* Mutex protecting device creation against CPU hotplug: */ -static DEFINE_MUTEX(therm_cpu_lock); - /* Get notified when a cpu comes on/off. Be hotplug friendly. */ static int thermal_throttle_cpu_callback(struct notifier_block *nfb, @@ -289,18 +286,14 @@ thermal_throttle_cpu_callback(struct notifier_block *nfb, switch (action) { case CPU_UP_PREPARE: case CPU_UP_PREPARE_FROZEN: - mutex_lock(&therm_cpu_lock); err = thermal_throttle_add_dev(dev, cpu); - mutex_unlock(&therm_cpu_lock); WARN_ON(err); break; case CPU_UP_CANCELED: case CPU_UP_CANCELED_FROZEN: case CPU_DEAD: case CPU_DEAD_FROZEN: - mutex_lock(&therm_cpu_lock); thermal_throttle_remove_dev(dev); - mutex_unlock(&therm_cpu_lock); break; } return notifier_from_errno(err); @@ -321,17 +314,11 @@ static __init int thermal_throttle_init_device(void) cpu_notifier_register_begin(); -#ifdef CONFIG_HOTPLUG_CPU - mutex_lock(&therm_cpu_lock); -#endif /* connect live CPUs to sysfs */ for_each_online_cpu(cpu) { err = thermal_throttle_add_dev(get_cpu_device(cpu), cpu); WARN_ON(err); } -#ifdef CONFIG_HOTPLUG_CPU - mutex_unlock(&therm_cpu_lock); -#endif __register_hotcpu_notifier(&thermal_throttle_cpu_notifier); cpu_notifier_register_done();