block: add block_{touch|dirty}_buffer tracepoint
The former is triggered from touch_buffer() and the latter
mark_buffer_dirty().
This is part of tracepoint additions to improve visiblity into
dirtying / writeback operations for io tracer and userland.
v2: Transformed writeback_dirty_buffer to block_dirty_buffer and made
it share TP definition with block_touch_buffer.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/include/trace/events/block.h b/include/trace/events/block.h
index b408f51..9961726 100644
--- a/include/trace/events/block.h
+++ b/include/trace/events/block.h
@@ -6,10 +6,61 @@
#include <linux/blktrace_api.h>
#include <linux/blkdev.h>
+#include <linux/buffer_head.h>
#include <linux/tracepoint.h>
#define RWBS_LEN 8
+DECLARE_EVENT_CLASS(block_buffer,
+
+ TP_PROTO(struct buffer_head *bh),
+
+ TP_ARGS(bh),
+
+ TP_STRUCT__entry (
+ __field( dev_t, dev )
+ __field( sector_t, sector )
+ __field( size_t, size )
+ ),
+
+ TP_fast_assign(
+ __entry->dev = bh->b_bdev->bd_dev;
+ __entry->sector = bh->b_blocknr;
+ __entry->size = bh->b_size;
+ ),
+
+ TP_printk("%d,%d sector=%llu size=%zu",
+ MAJOR(__entry->dev), MINOR(__entry->dev),
+ (unsigned long long)__entry->sector, __entry->size
+ )
+);
+
+/**
+ * block_touch_buffer - mark a buffer accessed
+ * @bh: buffer_head being touched
+ *
+ * Called from touch_buffer().
+ */
+DEFINE_EVENT(block_buffer, block_touch_buffer,
+
+ TP_PROTO(struct buffer_head *bh),
+
+ TP_ARGS(bh)
+);
+
+/**
+ * block_dirty_buffer - mark a buffer dirty
+ * @bh: buffer_head being dirtied
+ *
+ * Called from mark_buffer_dirty().
+ */
+DEFINE_EVENT(block_buffer, block_dirty_buffer,
+
+ TP_PROTO(struct buffer_head *bh),
+
+ TP_ARGS(bh)
+);
+
DECLARE_EVENT_CLASS(block_rq_with_error,
TP_PROTO(struct request_queue *q, struct request *rq),