From: Thomas Gleixner <tglx@linutronix.de>
Date: Tue, 22 Mar 2011 16:08:15 +0000 (+0100)
Subject: genirq: Provide a lockdep helper
X-Git-Tag: v2.6.39-rc1~62^2~1
X-Git-Url: https://openfabrics.org/gitweb/?a=commitdiff_plain;h=d3e17deb1790ee2123e9d11420be6411d1768b47;p=~shefty%2Frdma-dev.git

genirq: Provide a lockdep helper

Some irq chips need to call genirq functions for nested chips from
their callbacks. That upsets lockdep. So they need to set a different
lock class for those nested chips. Provide a helper function to avoid
open access to irq_desc.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---

diff --git a/include/linux/irqdesc.h b/include/linux/irqdesc.h
index 0b30662bc36..1595f9176b4 100644
--- a/include/linux/irqdesc.h
+++ b/include/linux/irqdesc.h
@@ -191,6 +191,15 @@ static inline void __set_irq_handler_unlocked(int irq,
 	desc->handle_irq = handler;
 }
 
+static inline void
+irq_set_lockdep_class(unsigned int irq, struct lock_class_key *class)
+{
+	struct irq_desc *desc = irq_to_desc(irq);
+
+	if (desc)
+		lockdep_set_class(&desc->lock, class);
+}
+
 #ifdef CONFIG_IRQ_PREFLOW_FASTEOI
 static inline void
 __irq_set_preflow_handler(unsigned int irq, irq_preflow_handler_t handler)