From: Yu Kuai <yukuai3@xxxxxxxxxx>
There are no functional changes, avoid dereferencing bitmap directly to
prepare inventing a new bitmap.
Also fix following checkpatch warning by using wq_has_sleeper().
WARNING: waitqueue_active without comment
Signed-off-by: Yu Kuai <yukuai3@xxxxxxxxxx>
---
drivers/md/md-bitmap.c | 2 ++
drivers/md/md-bitmap.h | 3 +++
drivers/md/raid1.c | 13 ++++++++-----
3 files changed, 13 insertions(+), 5 deletions(-)
diff --git a/drivers/md/md-bitmap.c b/drivers/md/md-bitmap.c
index ba83b99d6185..918510f36e33 100644
--- a/drivers/md/md-bitmap.c
+++ b/drivers/md/md-bitmap.c
@@ -2115,6 +2115,8 @@ int md_bitmap_get_stats(struct bitmap *bitmap, struct md_bitmap_stats *stats)
stats->file_pages = storage->file_pages;
stats->file = storage->file;
+ stats->behind_writes = atomic_read(&bitmap->behind_writes);
+ stats->behind_wait = wq_has_sleeper(&bitmap->behind_wait);
stats->events_cleared = bitmap->events_cleared;
return 0;
}
diff --git a/drivers/md/md-bitmap.h b/drivers/md/md-bitmap.h
index 870125670087..909a661383c6 100644
--- a/drivers/md/md-bitmap.h
+++ b/drivers/md/md-bitmap.h
@@ -236,6 +236,9 @@ struct bitmap {
struct md_bitmap_stats {
u64 events_cleared;
+ int behind_writes;
+ bool behind_wait;
+
unsigned long missing_pages;
unsigned long file_pages;
unsigned long sync_size;
diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
index 81fc100e7830..f9861f9103c2 100644
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -1603,16 +1603,19 @@ static void raid1_write_request(struct mddev *mddev, struct bio *bio,
continue;
if (first_clone) {
+ unsigned long max_write_behind =
+ mddev->bitmap_info.max_write_behind;
+ struct md_bitmap_stats stats;
+ int err;
+
/* do behind I/O ?
* Not if there are too many, or cannot
* allocate memory, or a reader on WriteMostly
* is waiting for behind writes to flush */
- if (bitmap && write_behind &&
- (atomic_read(&bitmap->behind_writes)
- < mddev->bitmap_info.max_write_behind) &&
- !waitqueue_active(&bitmap->behind_wait)) {
+ err = md_bitmap_get_stats(bitmap, &stats);
+ if (!err && write_behind && !stats.behind_wait &&
+ stats.behind_writes < max_write_behind)
alloc_behind_master_bio(r1_bio, bio);
- }
md_bitmap_startwrite(bitmap, r1_bio->sector, r1_bio->sectors,
test_bit(R1BIO_BehindIO, &r1_bio->state));
--
2.39.2
