trace: annotate bitfields in struct ring_buffer_event
This gets rid of a heap of false-positive warnings from the tracer
code due to the use of bitfields.
[rebased for mainline inclusion]
Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
diff --git a/include/linux/ring_buffer.h b/include/linux/ring_buffer.h
index 8670f15..29f8599 100644
--- a/include/linux/ring_buffer.h
+++ b/include/linux/ring_buffer.h
@@ -1,6 +1,7 @@
#ifndef _LINUX_RING_BUFFER_H
#define _LINUX_RING_BUFFER_H
+#include <linux/kmemcheck.h>
#include <linux/mm.h>
#include <linux/seq_file.h>
@@ -11,7 +12,10 @@
* Don't refer to this struct directly, use functions below.
*/
struct ring_buffer_event {
+ kmemcheck_bitfield_begin(bitfield);
u32 type_len:5, time_delta:27;
+ kmemcheck_bitfield_end(bitfield);
+
u32 array[];
};
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index 2e642b2..dc4dc70 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -10,6 +10,7 @@
#include <linux/debugfs.h>
#include <linux/uaccess.h>
#include <linux/hardirq.h>
+#include <linux/kmemcheck.h>
#include <linux/module.h>
#include <linux/percpu.h>
#include <linux/mutex.h>
@@ -1270,6 +1271,7 @@
if (tail < BUF_PAGE_SIZE) {
/* Mark the rest of the page with padding */
event = __rb_page_index(tail_page, tail);
+ kmemcheck_annotate_bitfield(event, bitfield);
rb_event_set_padding(event);
}
@@ -1327,6 +1329,7 @@
return NULL;
event = __rb_page_index(tail_page, tail);
+ kmemcheck_annotate_bitfield(event, bitfield);
rb_update_event(event, type, length);
/* The passed in type is zero for DATA */