Messages in this thread | | | Subject | Re: [PATCH] ledtrig-cpu: use spin_lock to replace mutex lock | From | Nathan Lynch <> | Date | Mon, 22 Oct 2012 17:28:14 -0500 |
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Hi Bryan,
On Thu, 2012-10-18 at 11:18 -0700, Bryan Wu wrote: > @@ -117,14 +117,14 @@ static int __init ledtrig_cpu_init(void) > for_each_possible_cpu(cpu) { > struct led_trigger_cpu *trig = &per_cpu(cpu_trig, cpu); > > - mutex_init(&trig->lock); > + spin_lock_init(&trig->lock); > > snprintf(trig->name, MAX_NAME_LEN, "cpu%d", cpu); > > - mutex_lock(&trig->lock); > + spin_lock(&trig->lock); > led_trigger_register_simple(trig->name, &trig->_trig); > trig->lock_is_inited = 1; > - mutex_unlock(&trig->lock); > + spin_unlock(&trig->lock);
I wouldn't know how to fix the original problem, but I don't think this patch is okay -- led_trigger_register_simple() does things that potentially sleep (GFP_KERNEL allocation, down_write), so it's not safe to call while holding a spinlock.
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