ring-buffer: disable all cpu buffers when one finds a problem

Currently the way RB_WARN_ON works, is to disable either the current
CPU buffer or all CPU buffers, depending on whether a ring_buffer or
ring_buffer_per_cpu struct was passed into the macro.

Most users of the RB_WARN_ON pass in the CPU buffer, so only the one
CPU buffer gets disabled but the rest are still active. This may
confuse users even though a warning is sent to the console.

This patch changes the macro to disable the entire buffer even if
the CPU buffer is passed in.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index c8d2a66e1d1fde776e2efacee78800d570324456..f83a42a79ee8a37aeaa0e2296eb3f8153de1ce56 100644 (file)
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -467,14 +467,19 @@ struct ring_buffer_iter {
 };
 
 /* buffer may be either ring_buffer or ring_buffer_per_cpu */
-#define RB_WARN_ON(buffer, cond)                               \
-       ({                                                      \
-               int _____ret = unlikely(cond);                  \
-               if (_____ret) {                                 \
-                       atomic_inc(&buffer->record_disabled);   \
-                       WARN_ON(1);                             \
-               }                                               \
-               _____ret;                                       \
+#define RB_WARN_ON(b, cond)                                            \
+       ({                                                              \
+               int _____ret = unlikely(cond);                          \
+               if (_____ret) {                                         \
+                       if (__same_type(*(b), struct ring_buffer_per_cpu)) { \
+                               struct ring_buffer_per_cpu *__b =       \
+                                       (void *)b;                      \
+                               atomic_inc(&__b->buffer->record_disabled); \
+                       } else                                          \
+                               atomic_inc(&b->record_disabled);        \
+                       WARN_ON(1);                                     \
+               }                                                       \
+               _____ret;                                               \
        })
 
 /* Up this if you want to test the TIME_EXTENTS and normalization */