summaryrefslogtreecommitdiffstats
path: root/drivers/md/dm.c
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2018-12-28 22:19:59 +0100
committerLinus Torvalds <torvalds@linux-foundation.org>2018-12-28 22:19:59 +0100
commit0e9da3fbf7d81f0f913b491c8de1ba7883d4f217 (patch)
tree2b3d25e3be60bf4ee40b4690c7bb9d6fa499ae69 /drivers/md/dm.c
parentMerge tag 'y2038-for-4.21' of ssh://gitolite.kernel.org:/pub/scm/linux/kernel... (diff)
parentkyber: use sbitmap add_wait_queue/list_del wait helpers (diff)
downloadlinux-0e9da3fbf7d81f0f913b491c8de1ba7883d4f217.tar.xz
linux-0e9da3fbf7d81f0f913b491c8de1ba7883d4f217.zip
Merge tag 'for-4.21/block-20181221' of git://git.kernel.dk/linux-block
Pull block updates from Jens Axboe: "This is the main pull request for block/storage for 4.21. Larger than usual, it was a busy round with lots of goodies queued up. Most notable is the removal of the old IO stack, which has been a long time coming. No new features for a while, everything coming in this week has all been fixes for things that were previously merged. This contains: - Use atomic counters instead of semaphores for mtip32xx (Arnd) - Cleanup of the mtip32xx request setup (Christoph) - Fix for circular locking dependency in loop (Jan, Tetsuo) - bcache (Coly, Guoju, Shenghui) * Optimizations for writeback caching * Various fixes and improvements - nvme (Chaitanya, Christoph, Sagi, Jay, me, Keith) * host and target support for NVMe over TCP * Error log page support * Support for separate read/write/poll queues * Much improved polling * discard OOM fallback * Tracepoint improvements - lightnvm (Hans, Hua, Igor, Matias, Javier) * Igor added packed metadata to pblk. Now drives without metadata per LBA can be used as well. * Fix from Geert on uninitialized value on chunk metadata reads. * Fixes from Hans and Javier to pblk recovery and write path. * Fix from Hua Su to fix a race condition in the pblk recovery code. * Scan optimization added to pblk recovery from Zhoujie. * Small geometry cleanup from me. - Conversion of the last few drivers that used the legacy path to blk-mq (me) - Removal of legacy IO path in SCSI (me, Christoph) - Removal of legacy IO stack and schedulers (me) - Support for much better polling, now without interrupts at all. blk-mq adds support for multiple queue maps, which enables us to have a map per type. This in turn enables nvme to have separate completion queues for polling, which can then be interrupt-less. Also means we're ready for async polled IO, which is hopefully coming in the next release. - Killing of (now) unused block exports (Christoph) - Unification of the blk-rq-qos and blk-wbt wait handling (Josef) - Support for zoned testing with null_blk (Masato) - sx8 conversion to per-host tag sets (Christoph) - IO priority improvements (Damien) - mq-deadline zoned fix (Damien) - Ref count blkcg series (Dennis) - Lots of blk-mq improvements and speedups (me) - sbitmap scalability improvements (me) - Make core inflight IO accounting per-cpu (Mikulas) - Export timeout setting in sysfs (Weiping) - Cleanup the direct issue path (Jianchao) - Export blk-wbt internals in block debugfs for easier debugging (Ming) - Lots of other fixes and improvements" * tag 'for-4.21/block-20181221' of git://git.kernel.dk/linux-block: (364 commits) kyber: use sbitmap add_wait_queue/list_del wait helpers sbitmap: add helpers for add/del wait queue handling block: save irq state in blkg_lookup_create() dm: don't reuse bio for flushes nvme-pci: trace SQ status on completions nvme-rdma: implement polling queue map nvme-fabrics: allow user to pass in nr_poll_queues nvme-fabrics: allow nvmf_connect_io_queue to poll nvme-core: optionally poll sync commands block: make request_to_qc_t public nvme-tcp: fix spelling mistake "attepmpt" -> "attempt" nvme-tcp: fix endianess annotations nvmet-tcp: fix endianess annotations nvme-pci: refactor nvme_poll_irqdisable to make sparse happy nvme-pci: only set nr_maps to 2 if poll queues are supported nvmet: use a macro for default error location nvmet: fix comparison of a u16 with -1 blk-mq: enable IO poll if .nr_queues of type poll > 0 blk-mq: change blk_mq_queue_busy() to blk_mq_queue_inflight() blk-mq: skip zero-queue maps in blk_mq_map_swqueue ...
Diffstat (limited to 'drivers/md/dm.c')
-rw-r--r--drivers/md/dm.c79
1 files changed, 52 insertions, 27 deletions
diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 63a7c416b224..a4a06982ed91 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -646,26 +646,38 @@ static void free_tio(struct dm_target_io *tio)
bio_put(&tio->clone);
}
-int md_in_flight(struct mapped_device *md)
+static bool md_in_flight_bios(struct mapped_device *md)
{
- return atomic_read(&md->pending[READ]) +
- atomic_read(&md->pending[WRITE]);
+ int cpu;
+ struct hd_struct *part = &dm_disk(md)->part0;
+ long sum = 0;
+
+ for_each_possible_cpu(cpu) {
+ sum += part_stat_local_read_cpu(part, in_flight[0], cpu);
+ sum += part_stat_local_read_cpu(part, in_flight[1], cpu);
+ }
+
+ return sum != 0;
+}
+
+static bool md_in_flight(struct mapped_device *md)
+{
+ if (queue_is_mq(md->queue))
+ return blk_mq_queue_inflight(md->queue);
+ else
+ return md_in_flight_bios(md);
}
static void start_io_acct(struct dm_io *io)
{
struct mapped_device *md = io->md;
struct bio *bio = io->orig_bio;
- int rw = bio_data_dir(bio);
io->start_time = jiffies;
generic_start_io_acct(md->queue, bio_op(bio), bio_sectors(bio),
&dm_disk(md)->part0);
- atomic_set(&dm_disk(md)->part0.in_flight[rw],
- atomic_inc_return(&md->pending[rw]));
-
if (unlikely(dm_stats_used(&md->stats)))
dm_stats_account_io(&md->stats, bio_data_dir(bio),
bio->bi_iter.bi_sector, bio_sectors(bio),
@@ -677,8 +689,6 @@ static void end_io_acct(struct dm_io *io)
struct mapped_device *md = io->md;
struct bio *bio = io->orig_bio;
unsigned long duration = jiffies - io->start_time;
- int pending;
- int rw = bio_data_dir(bio);
generic_end_io_acct(md->queue, bio_op(bio), &dm_disk(md)->part0,
io->start_time);
@@ -688,16 +698,8 @@ static void end_io_acct(struct dm_io *io)
bio->bi_iter.bi_sector, bio_sectors(bio),
true, duration, &io->stats_aux);
- /*
- * After this is decremented the bio must not be touched if it is
- * a flush.
- */
- pending = atomic_dec_return(&md->pending[rw]);
- atomic_set(&dm_disk(md)->part0.in_flight[rw], pending);
- pending += atomic_read(&md->pending[rw^0x1]);
-
/* nudge anyone waiting on suspend queue */
- if (!pending)
+ if (unlikely(waitqueue_active(&md->wait)))
wake_up(&md->wait);
}
@@ -1417,10 +1419,21 @@ static int __send_empty_flush(struct clone_info *ci)
unsigned target_nr = 0;
struct dm_target *ti;
+ /*
+ * Empty flush uses a statically initialized bio, as the base for
+ * cloning. However, blkg association requires that a bdev is
+ * associated with a gendisk, which doesn't happen until the bdev is
+ * opened. So, blkg association is done at issue time of the flush
+ * rather than when the device is created in alloc_dev().
+ */
+ bio_set_dev(ci->bio, ci->io->md->bdev);
+
BUG_ON(bio_has_data(ci->bio));
while ((ti = dm_table_get_target(ci->map, target_nr++)))
__send_duplicate_bios(ci, ti, ti->num_flush_bios, NULL);
+ bio_disassociate_blkg(ci->bio);
+
return 0;
}
@@ -1598,7 +1611,16 @@ static blk_qc_t __split_and_process_bio(struct mapped_device *md,
init_clone_info(&ci, md, map, bio);
if (bio->bi_opf & REQ_PREFLUSH) {
- ci.bio = &ci.io->md->flush_bio;
+ struct bio flush_bio;
+
+ /*
+ * Use an on-stack bio for this, it's safe since we don't
+ * need to reference it after submit. It's just used as
+ * the basis for the clone(s).
+ */
+ bio_init(&flush_bio, NULL, 0);
+ flush_bio.bi_opf = REQ_OP_WRITE | REQ_PREFLUSH | REQ_SYNC;
+ ci.bio = &flush_bio;
ci.sector_count = 0;
error = __send_empty_flush(&ci);
/* dec_pending submits any data associated with flush */
@@ -1654,7 +1676,16 @@ static blk_qc_t __process_bio(struct mapped_device *md,
init_clone_info(&ci, md, map, bio);
if (bio->bi_opf & REQ_PREFLUSH) {
- ci.bio = &ci.io->md->flush_bio;
+ struct bio flush_bio;
+
+ /*
+ * Use an on-stack bio for this, it's safe since we don't
+ * need to reference it after submit. It's just used as
+ * the basis for the clone(s).
+ */
+ bio_init(&flush_bio, NULL, 0);
+ flush_bio.bi_opf = REQ_OP_WRITE | REQ_PREFLUSH | REQ_SYNC;
+ ci.bio = &flush_bio;
ci.sector_count = 0;
error = __send_empty_flush(&ci);
/* dec_pending submits any data associated with flush */
@@ -1898,7 +1929,7 @@ static struct mapped_device *alloc_dev(int minor)
INIT_LIST_HEAD(&md->table_devices);
spin_lock_init(&md->uevent_lock);
- md->queue = blk_alloc_queue_node(GFP_KERNEL, numa_node_id, NULL);
+ md->queue = blk_alloc_queue_node(GFP_KERNEL, numa_node_id);
if (!md->queue)
goto bad;
md->queue->queuedata = md;
@@ -1908,8 +1939,6 @@ static struct mapped_device *alloc_dev(int minor)
if (!md->disk)
goto bad;
- atomic_set(&md->pending[0], 0);
- atomic_set(&md->pending[1], 0);
init_waitqueue_head(&md->wait);
INIT_WORK(&md->work, dm_wq_work);
init_waitqueue_head(&md->eventq);
@@ -1940,10 +1969,6 @@ static struct mapped_device *alloc_dev(int minor)
if (!md->bdev)
goto bad;
- bio_init(&md->flush_bio, NULL, 0);
- bio_set_dev(&md->flush_bio, md->bdev);
- md->flush_bio.bi_opf = REQ_OP_WRITE | REQ_PREFLUSH | REQ_SYNC;
-
dm_stats_init(&md->stats);
/* Populate the mapping, nobody knows we exist yet */