From e262f34741522e0d821642e5449c6eeb512723fc Mon Sep 17 00:00:00 2001 From: Mikulas Patocka Date: Tue, 9 Jun 2015 17:22:49 -0400 Subject: [PATCH] dm stats: add support for request-based DM devices This makes it possible to use dm stats with DM multipath. Signed-off-by: Mikulas Patocka Signed-off-by: Mike Snitzer --- drivers/md/dm-stats.c | 5 ----- drivers/md/dm.c | 26 ++++++++++++++++++++++++++ 2 files changed, 26 insertions(+), 5 deletions(-) diff --git a/drivers/md/dm-stats.c b/drivers/md/dm-stats.c index faf1071ef631..8a8b48fa901a 100644 --- a/drivers/md/dm-stats.c +++ b/drivers/md/dm-stats.c @@ -1155,11 +1155,6 @@ int dm_stats_message(struct mapped_device *md, unsigned argc, char **argv, { int r; - if (dm_request_based(md)) { - DMWARN("Statistics are only supported for bio-based devices"); - return -EOPNOTSUPP; - } - /* All messages here must start with '@' */ if (!strcasecmp(argv[0], "@stats_create")) r = message_stats_create(md, argc, argv, result, maxlen); diff --git a/drivers/md/dm.c b/drivers/md/dm.c index 767bce906588..90dc49e3c78f 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -86,6 +86,9 @@ struct dm_rq_target_io { struct kthread_work work; int error; union map_info info; + struct dm_stats_aux stats_aux; + unsigned long duration_jiffies; + unsigned n_sectors; }; /* @@ -995,6 +998,17 @@ static struct dm_rq_target_io *tio_from_request(struct request *rq) return (rq->q->mq_ops ? blk_mq_rq_to_pdu(rq) : rq->special); } +static void rq_end_stats(struct mapped_device *md, struct request *orig) +{ + if (unlikely(dm_stats_used(&md->stats))) { + struct dm_rq_target_io *tio = tio_from_request(orig); + tio->duration_jiffies = jiffies - tio->duration_jiffies; + dm_stats_account_io(&md->stats, orig->cmd_flags, blk_rq_pos(orig), + tio->n_sectors, true, tio->duration_jiffies, + &tio->stats_aux); + } +} + /* * Don't touch any member of the md after calling this function because * the md may be freed in dm_put() at the end of this function. @@ -1078,6 +1092,7 @@ static void dm_end_request(struct request *clone, int error) } free_rq_clone(clone); + rq_end_stats(md, rq); if (!rq->q->mq_ops) blk_end_request_all(rq, error); else @@ -1120,6 +1135,7 @@ static void dm_requeue_original_request(struct mapped_device *md, dm_unprep_request(rq); + rq_end_stats(md, rq); if (!rq->q->mq_ops) old_requeue_request(rq); else { @@ -1211,6 +1227,7 @@ static void dm_softirq_done(struct request *rq) int rw; if (!clone) { + rq_end_stats(tio->md, rq); rw = rq_data_dir(rq); if (!rq->q->mq_ops) { blk_end_request_all(rq, tio->error); @@ -1943,6 +1960,14 @@ static void dm_start_request(struct mapped_device *md, struct request *orig) md->last_rq_start_time = ktime_get(); } + if (unlikely(dm_stats_used(&md->stats))) { + struct dm_rq_target_io *tio = tio_from_request(orig); + tio->duration_jiffies = jiffies; + tio->n_sectors = blk_rq_sectors(orig); + dm_stats_account_io(&md->stats, orig->cmd_flags, blk_rq_pos(orig), + tio->n_sectors, false, 0, &tio->stats_aux); + } + /* * Hold the md reference here for the in-flight I/O. * We can't rely on the reference count by device opener, @@ -2689,6 +2714,7 @@ static int dm_mq_queue_rq(struct blk_mq_hw_ctx *hctx, /* Direct call is fine since .queue_rq allows allocations */ if (map_request(tio, rq, md) == DM_MAPIO_REQUEUE) { /* Undo dm_start_request() before requeuing */ + rq_end_stats(md, rq); rq_completed(md, rq_data_dir(rq), false); return BLK_MQ_RQ_QUEUE_BUSY; } -- 2.20.1