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>
This commit is contained in:
Tejun Heo 2013-01-11 13:06:36 -08:00 committed by Jens Axboe
parent f0059afd3e
commit 5305cb8308
2 changed files with 55 additions and 0 deletions

View File

@ -41,6 +41,7 @@
#include <linux/bitops.h>
#include <linux/mpage.h>
#include <linux/bit_spinlock.h>
#include <trace/events/block.h>
static int fsync_buffers_list(spinlock_t *lock, struct list_head *list);
@ -55,6 +56,7 @@ EXPORT_SYMBOL(init_buffer);
inline void touch_buffer(struct buffer_head *bh)
{
trace_block_touch_buffer(bh);
mark_page_accessed(bh->b_page);
}
EXPORT_SYMBOL(touch_buffer);
@ -1119,6 +1121,8 @@ void mark_buffer_dirty(struct buffer_head *bh)
{
WARN_ON_ONCE(!buffer_uptodate(bh));
trace_block_dirty_buffer(bh);
/*
* Very *carefully* optimize the it-is-already-dirty case.
*

View File

@ -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),