1 files changed, 70 insertions, 7 deletions

diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h
index da3e0dbe61d4..d5afee95fd43 100644
--- a/include/linux/interrupt.h
+++ b/include/linux/interrupt.h
@@ -10,6 +10,7 @@
 #include <linux/irqreturn.h>
 #include <linux/hardirq.h>
 #include <linux/sched.h>
+#include <linux/irqflags.h>
 #include <asm/atomic.h>
 #include <asm/ptrace.h>
 #include <asm/system.h>
@@ -80,12 +81,64 @@ extern int request_irq(unsigned int,
                        unsigned long, const char *, void *);
 extern void free_irq(unsigned int, void *);
 
+/*
+ * On lockdep we dont want to enable hardirqs in hardirq
+ * context. Use local_irq_enable_in_hardirq() to annotate
+ * kernel code that has to do this nevertheless (pretty much
+ * the only valid case is for old/broken hardware that is
+ * insanely slow).
+ *
+ * NOTE: in theory this might break fragile code that relies
+ * on hardirq delivery - in practice we dont seem to have such
+ * places left. So the only effect should be slightly increased
+ * irqs-off latencies.
+ */
+#ifdef CONFIG_LOCKDEP
+# define local_irq_enable_in_hardirq()  do { } while (0)
+#else
+# define local_irq_enable_in_hardirq()  local_irq_enable()
+#endif
 
 #ifdef CONFIG_GENERIC_HARDIRQS
 extern void disable_irq_nosync(unsigned int irq);
 extern void disable_irq(unsigned int irq);
 extern void enable_irq(unsigned int irq);
 
+/*
+ * Special lockdep variants of irq disabling/enabling.
+ * These should be used for locking constructs that
+ * know that a particular irq context which is disabled,
+ * and which is the only irq-context user of a lock,
+ * that it's safe to take the lock in the irq-disabled
+ * section without disabling hardirqs.
+ *
+ * On !CONFIG_LOCKDEP they are equivalent to the normal
+ * irq disable/enable methods.
+ */
+static inline void disable_irq_nosync_lockdep(unsigned int irq)
+{
+        disable_irq_nosync(irq);
+#ifdef CONFIG_LOCKDEP
+        local_irq_disable();
+#endif
+}
+
+static inline void disable_irq_lockdep(unsigned int irq)
+{
+        disable_irq(irq);
+#ifdef CONFIG_LOCKDEP
+        local_irq_disable();
+#endif
+}
+
+static inline void enable_irq_lockdep(unsigned int irq)
+{
+#ifdef CONFIG_LOCKDEP
+        local_irq_enable();
+#endif
+        enable_irq(irq);
+}
+
 /* IRQ wakeup (PM) control: */
 extern int set_irq_wake(unsigned int irq, unsigned int on);
 
@@ -99,7 +152,19 @@ static inline int disable_irq_wake(unsigned int irq)
         return set_irq_wake(irq, 0);
 }
 
-#endif
+#else /* !CONFIG_GENERIC_HARDIRQS */
+/*
+ * NOTE: non-genirq architectures, if they want to support the lock
+ * validator need to define the methods below in their asm/irq.h
+ * files, under an #ifdef CONFIG_LOCKDEP section.
+ */
+# ifndef CONFIG_LOCKDEP
+#  define disable_irq_nosync_lockdep(irq)       disable_irq_nosync(irq)
+#  define disable_irq_lockdep(irq)              disable_irq(irq)
+#  define enable_irq_lockdep(irq)               enable_irq(irq)
+# endif
+
+#endif /* CONFIG_GENERIC_HARDIRQS */
 
 #ifndef __ARCH_SET_SOFTIRQ_PENDING
 #define set_softirq_pending(x) (local_softirq_pending() = (x))
@@ -135,13 +200,11 @@ static inline void __deprecated save_and_cli(unsigned long *x)
 #define save_and_cli(x) save_and_cli(&x)
 #endif /* CONFIG_SMP */
 
-/* SoftIRQ primitives.  */
-#define local_bh_disable() \
-                do { add_preempt_count(SOFTIRQ_OFFSET); barrier(); } while (0)
-#define __local_bh_enable() \
-                do { barrier(); sub_preempt_count(SOFTIRQ_OFFSET); } while (0)
-
+extern void local_bh_disable(void);
+extern void __local_bh_enable(void);
+extern void _local_bh_enable(void);
 extern void local_bh_enable(void);
+extern void local_bh_enable_ip(unsigned long ip);
 
 /* PLEASE, avoid to allocate new softirqs, if you need not _really_ high
    frequency threaded job scheduling. For almost all the purposes