ring-buffer: allow tracing_off to be used in core kernel code
tracing_off() is the fastest way to stop recording to the ring buffers.
This may be used in places like panic and die, just before the
ftrace_dump is called.
This patch adds the appropriate CPP conditionals to make it a stub
function when the ring buffer is not configured it.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
diff --git a/include/linux/ring_buffer.h b/include/linux/ring_buffer.h
index b3b3596..ac94c06 100644
--- a/include/linux/ring_buffer.h
+++ b/include/linux/ring_buffer.h
@@ -124,9 +124,18 @@
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);