[PATCH] lockdep: irqtrace subsystem, core

Accurate hard-IRQ-flags and softirq-flags state tracing.

This allows us to attach extra functionality to IRQ flags on/off
events (such as trace-on/off).

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/include/asm-powerpc/irqflags.h b/include/asm-powerpc/irqflags.h
new file mode 100644
index 0000000..7970cba
--- /dev/null
+++ b/include/asm-powerpc/irqflags.h
@@ -0,0 +1,31 @@
+/*
+ * include/asm-powerpc/irqflags.h
+ *
+ * IRQ flags handling
+ *
+ * This file gets included from lowlevel asm headers too, to provide
+ * wrapped versions of the local_irq_*() APIs, based on the
+ * raw_local_irq_*() macros from the lowlevel headers.
+ */
+#ifndef _ASM_IRQFLAGS_H
+#define _ASM_IRQFLAGS_H
+
+/*
+ * Get definitions for raw_local_save_flags(x), etc.
+ */
+#include <asm-powerpc/hw_irq.h>
+
+/*
+ * Do the CPU's IRQ-state tracing from assembly code. We call a
+ * C function, so save all the C-clobbered registers:
+ */
+#ifdef CONFIG_TRACE_IRQFLAGS
+
+#error No support on PowerPC yet for CONFIG_TRACE_IRQFLAGS
+
+#else
+# define TRACE_IRQS_ON
+# define TRACE_IRQS_OFF
+#endif
+
+#endif