Merge branch 'tip/tracing/core/devel' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-2.6-trace into tracing/ftrace

Conflicts:
	kernel/trace/trace_hw_branches.c

4 files changed, 26 insertions, 2 deletions

diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h
index 7840e718c6c7..5e302d636fc2 100644
--- a/include/linux/ftrace.h
+++ b/include/linux/ftrace.h
@@ -140,7 +140,7 @@ static inline int ftrace_disable_ftrace_graph_caller(void) { return 0; }
 #endif
 
 /**
- * ftrace_make_nop - convert code into top
+ * ftrace_make_nop - convert code into nop
  * @mod: module structure if called by module load initialization
  * @rec: the mcount call site record
  * @addr: the address that the call site should be calling
diff --git a/include/linux/ftrace_irq.h b/include/linux/ftrace_irq.h
index 366a054d0b05..dca7bf8cffe2 100644
--- a/include/linux/ftrace_irq.h
+++ b/include/linux/ftrace_irq.h
@@ -2,7 +2,7 @@
 #define _LINUX_FTRACE_IRQ_H
 
 
-#if defined(CONFIG_DYNAMIC_FTRACE) || defined(CONFIG_FUNCTION_GRAPH_TRACER)
+#ifdef CONFIG_FTRACE_NMI_ENTER
 extern void ftrace_nmi_enter(void);
 extern void ftrace_nmi_exit(void);
 #else
diff --git a/include/linux/hardirq.h b/include/linux/hardirq.h
index f83288347dda..f3cf86e1465b 100644
--- a/include/linux/hardirq.h
+++ b/include/linux/hardirq.h
@@ -61,6 +61,12 @@
 #error PREEMPT_ACTIVE is too low!
 #endif
 
+#define NMI_OFFSET      (PREEMPT_ACTIVE << 1)
+
+#if NMI_OFFSET >= 0x80000000
+#error PREEMPT_ACTIVE too high!
+#endif
+
 #define hardirq_count() (preempt_count() & HARDIRQ_MASK)
 #define softirq_count() (preempt_count() & SOFTIRQ_MASK)
 #define irq_count()     (preempt_count() & (HARDIRQ_MASK | SOFTIRQ_MASK))
@@ -73,6 +79,11 @@
 #define in_softirq()            (softirq_count())
 #define in_interrupt()          (irq_count())
 
+/*
+ * Are we in NMI context?
+ */
+#define in_nmi()        (preempt_count() & NMI_OFFSET)
+
 #if defined(CONFIG_PREEMPT)
 # define PREEMPT_INATOMIC_BASE kernel_locked()
 # define PREEMPT_CHECK_OFFSET 1
@@ -167,6 +178,8 @@ extern void irq_exit(void);
 #define nmi_enter()                             \
         do {                                    \
                 ftrace_nmi_enter();             \
+                BUG_ON(in_nmi());               \
+                add_preempt_count(NMI_OFFSET);  \
                 lockdep_off();                  \
                 rcu_nmi_enter();                \
                 __irq_enter();                  \
@@ -177,6 +190,8 @@ extern void irq_exit(void);
                 __irq_exit();                   \
                 rcu_nmi_exit();                 \
                 lockdep_on();                   \
+                BUG_ON(!in_nmi());              \
+                sub_preempt_count(NMI_OFFSET);  \
                 ftrace_nmi_exit();              \
         } while (0)
 
diff --git a/include/linux/ring_buffer.h b/include/linux/ring_buffer.h
index 3110d92e7d81..3c103d636da3 100644
--- a/include/linux/ring_buffer.h
+++ b/include/linux/ring_buffer.h
@@ -121,9 +121,18 @@ unsigned long ring_buffer_overrun_cpu(struct ring_buffer *buffer, int cpu);
 u64 ring_buffer_time_stamp(int cpu);
 void ring_buffer_normalize_time_stamp(int cpu, u64 *ts);
 
+/*
+ * The below functions are fine to use outside the tracing facility.
+ */
+#ifdef CONFIG_RING_BUFFER
 void tracing_on(void);
 void tracing_off(void);
 void tracing_off_permanent(void);
+#else
+static inline void tracing_on(void) { }
+static inline void tracing_off(void) { }
+static inline void tracing_off_permanent(void) { }
+#endif
 
 void *ring_buffer_alloc_read_page(struct ring_buffer *buffer);
 void ring_buffer_free_read_page(struct ring_buffer *buffer, void *data);