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Diffstat (limited to 'drivers/md/dm.c')
-rw-r--r--drivers/md/dm.c39
1 files changed, 37 insertions, 2 deletions
diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 8c16359f8b0..e9adeb9d172 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -31,6 +31,7 @@ struct dm_io {
int error;
struct bio *bio;
atomic_t io_count;
+ unsigned long start_time;
};
/*
@@ -244,6 +245,36 @@ static inline void free_tio(struct mapped_device *md, struct target_io *tio)
mempool_free(tio, md->tio_pool);
}
+static void start_io_acct(struct dm_io *io)
+{
+ struct mapped_device *md = io->md;
+
+ io->start_time = jiffies;
+
+ preempt_disable();
+ disk_round_stats(dm_disk(md));
+ preempt_enable();
+ dm_disk(md)->in_flight = atomic_inc_return(&md->pending);
+}
+
+static int end_io_acct(struct dm_io *io)
+{
+ struct mapped_device *md = io->md;
+ struct bio *bio = io->bio;
+ unsigned long duration = jiffies - io->start_time;
+ int pending;
+ int rw = bio_data_dir(bio);
+
+ preempt_disable();
+ disk_round_stats(dm_disk(md));
+ preempt_enable();
+ dm_disk(md)->in_flight = pending = atomic_dec_return(&md->pending);
+
+ disk_stat_add(dm_disk(md), ticks[rw], duration);
+
+ return !pending;
+}
+
/*
* Add the bio to the list of deferred io.
*/
@@ -299,7 +330,7 @@ static void dec_pending(struct dm_io *io, int error)
io->error = error;
if (atomic_dec_and_test(&io->io_count)) {
- if (atomic_dec_and_test(&io->md->pending))
+ if (end_io_acct(io))
/* nudge anyone waiting on suspend queue */
wake_up(&io->md->wait);
@@ -554,7 +585,7 @@ static void __split_bio(struct mapped_device *md, struct bio *bio)
ci.sector_count = bio_sectors(bio);
ci.idx = bio->bi_idx;
- atomic_inc(&md->pending);
+ start_io_acct(ci.io);
while (ci.sector_count)
__clone_and_map(&ci);
@@ -573,10 +604,14 @@ static void __split_bio(struct mapped_device *md, struct bio *bio)
static int dm_request(request_queue_t *q, struct bio *bio)
{
int r;
+ int rw = bio_data_dir(bio);
struct mapped_device *md = q->queuedata;
down_read(&md->io_lock);
+ disk_stat_inc(dm_disk(md), ios[rw]);
+ disk_stat_add(dm_disk(md), sectors[rw], bio_sectors(bio));
+
/*
* If we're suspended we have to queue
* this io for later.