ring-buffer: Add enum names for the context levels

Instead of having hard coded numbers for the context levels, use
enums to describe them more.

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

1 files changed, 22 insertions, 5 deletions

diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index 0fc5add6423b..6260717c18e3 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -400,6 +400,23 @@ struct rb_irq_work {
 };
 
 /*
+ * Used for which event context the event is in.
+ *  NMI     = 0
+ *  IRQ     = 1
+ *  SOFTIRQ = 2
+ *  NORMAL  = 3
+ *
+ * See trace_recursive_lock() comment below for more details.
+ */
+enum {
+        RB_CTX_NMI,
+        RB_CTX_IRQ,
+        RB_CTX_SOFTIRQ,
+        RB_CTX_NORMAL,
+        RB_CTX_MAX
+};
+
+/*
  * head_page == tail_page && head == tail then buffer is empty.
  */
 struct ring_buffer_per_cpu {
@@ -2173,7 +2190,7 @@ static unsigned rb_calculate_event_length(unsigned length)
 
         /* zero length can cause confusions */
         if (!length)
-                length = 1;
+                length++;
 
         if (length > RB_MAX_SMALL_DATA || RB_FORCE_8BYTE_ALIGNMENT)
                 length += sizeof(event.array[0]);
@@ -2631,13 +2648,13 @@ trace_recursive_lock(struct ring_buffer_per_cpu *cpu_buffer)
 
         if (in_interrupt()) {
                 if (in_nmi())
-                        bit = 0;
+                        bit = RB_CTX_NMI;
                 else if (in_irq())
-                        bit = 1;
+                        bit = RB_CTX_IRQ;
                 else
-                        bit = 2;
+                        bit = RB_CTX_SOFTIRQ;
         } else
-                bit = 3;
+                bit = RB_CTX_NORMAL;
 
         if (unlikely(val & (1 << bit)))
                 return 1;