[for-next][PATCH 3/3] ring-buffer: Add enum names for the context levels

From: Steven Rostedt
Date: Sat May 30 2015 - 05:43:24 EST


From: "Steven Rostedt (Red Hat)" <rostedt@xxxxxxxxxxx>

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

Signed-off-by: Steven Rostedt <rostedt@xxxxxxxxxxx>
---
kernel/trace/ring_buffer.c | 27 ++++++++++++++++++++++-----
1 file 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;
--
2.1.4


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