commit ad3fc798800fb7ca04c1dfc439dba946818048d8 upstream.
The commit 41d2d848e5c0 ("md: improve io stats accounting") could cause
double fault problem per the report [1], and also it is not correct to
change ->bi_end_io if md don't own it, so let's revert it.
And io stats accounting will be replemented in later commits.
[1]. https://lore.kernel.org/linux-raid/3bf04253-3fad-434a-63a7-20214e38cf26@xxxxxxxxx/T/#t
Fixes: 41d2d848e5c0 ("md: improve io stats accounting")
Signed-off-by: Guoqing Jiang <jiangguoqing@xxxxxxxxxx>
Signed-off-by: Song Liu <song@xxxxxxxxxx>
[GM: backport to 5.10-stable]
Signed-off-by: Guillaume Morin <guillaume@xxxxxxxxxxx>
---
drivers/md/md.c | 57 +++++++++++--------------------------------------
drivers/md/md.h | 1 -
2 files changed, 12 insertions(+), 46 deletions(-)
diff --git a/drivers/md/md.c b/drivers/md/md.c
index 2069b16b50ec..cc3876500c4b 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -459,34 +459,12 @@ void md_handle_request(struct mddev *mddev, struct bio *bio)
}
EXPORT_SYMBOL(md_handle_request);
-struct md_io {
- struct mddev *mddev;
- bio_end_io_t *orig_bi_end_io;
- void *orig_bi_private;
- unsigned long start_time;
- struct hd_struct *part;
-};
-
-static void md_end_io(struct bio *bio)
-{
- struct md_io *md_io = bio->bi_private;
- struct mddev *mddev = md_io->mddev;
-
- part_end_io_acct(md_io->part, bio, md_io->start_time);
-
- bio->bi_end_io = md_io->orig_bi_end_io;
- bio->bi_private = md_io->orig_bi_private;
-
- mempool_free(md_io, &mddev->md_io_pool);
-
- if (bio->bi_end_io)
- bio->bi_end_io(bio);
-}
-
static blk_qc_t md_submit_bio(struct bio *bio)
{
const int rw = bio_data_dir(bio);
+ const int sgrp = op_stat_group(bio_op(bio));
struct mddev *mddev = bio->bi_disk->private_data;
+ unsigned int sectors;
if (mddev == NULL || mddev->pers == NULL) {
bio_io_error(bio);
@@ -507,26 +485,21 @@ static blk_qc_t md_submit_bio(struct bio *bio)
return BLK_QC_T_NONE;
}
- if (bio->bi_end_io != md_end_io) {
- struct md_io *md_io;
-
- md_io = mempool_alloc(&mddev->md_io_pool, GFP_NOIO);
- md_io->mddev = mddev;
- md_io->orig_bi_end_io = bio->bi_end_io;
- md_io->orig_bi_private = bio->bi_private;
-
- bio->bi_end_io = md_end_io;
- bio->bi_private = md_io;
-
- md_io->start_time = part_start_io_acct(mddev->gendisk,
- &md_io->part, bio);
- }
-
+ /*
+ * save the sectors now since our bio can
+ * go away inside make_request
+ */
+ sectors = bio_sectors(bio);
/* bio could be mergeable after passing to underlayer */
bio->bi_opf &= ~REQ_NOMERGE;
md_handle_request(mddev, bio);
+ part_stat_lock();
+ part_stat_inc(&mddev->gendisk->part0, ios[sgrp]);
+ part_stat_add(&mddev->gendisk->part0, sectors[sgrp], sectors);
+ part_stat_unlock();
+
return BLK_QC_T_NONE;
}
@@ -5636,7 +5609,6 @@ static void md_free(struct kobject *ko)
bioset_exit(&mddev->bio_set);
bioset_exit(&mddev->sync_set);
- mempool_exit(&mddev->md_io_pool);
kfree(mddev);
}
@@ -5732,11 +5704,6 @@ static int md_alloc(dev_t dev, char *name)
*/
mddev->hold_active = UNTIL_STOP;
- error = mempool_init_kmalloc_pool(&mddev->md_io_pool, BIO_POOL_SIZE,
- sizeof(struct md_io));
- if (error)
- goto abort;
-
error = -ENOMEM;
mddev->queue = blk_alloc_queue(NUMA_NO_NODE);
if (!mddev->queue)
diff --git a/drivers/md/md.h b/drivers/md/md.h
index 2175a5ac4f7c..c94811cf2600 100644
--- a/drivers/md/md.h
+++ b/drivers/md/md.h
@@ -487,7 +487,6 @@ struct mddev {
struct bio_set sync_set; /* for sync operations like
* metadata and bitmap writes
*/
- mempool_t md_io_pool;
/* Generic flush handling.
* The last to finish preflush schedules a worker to submit
--
2.23.0
--
Guillaume Morin <guillaume@xxxxxxxxxxx>
