[md-6.12,01/41] md/raid1: use md_bitmap_wait_behind_writes() in raid1_read_request()

Commit Message

Yu Kuai Aug. 22, 2024, 2:46 a.m. UTC

From: Yu Kuai <[e-mail]>

Use the existed helper instead of open coding it to make the code cleaner.
There are no functional changes, and also avoid dereferencing bitmap
directly to prepare inventing a new bitmap.

Noted that this patch also export md_bitmap_wait_behind_writes(), which
is necessary for now, and the exported api will be removed in following
patches to convert bitmap apis into ops.

Signed-off-by: Yu Kuai <[e-mail]>
---
 drivers/md/md-bitmap.c | 1 +
 drivers/md/raid1.c     | 7 ++-----
 2 files changed, 3 insertions(+), 5 deletions(-)

Patch

diff --git a/drivers/md/md-bitmap.c b/drivers/md/md-bitmap.c
index 08232d8dc815..08743dcc70f1 100644
--- a/drivers/md/md-bitmap.c
+++ b/drivers/md/md-bitmap.c
@@ -1851,6 +1851,7 @@  void md_bitmap_wait_behind_writes(struct mddev *mddev)
 			   atomic_read(&bitmap->behind_writes) == 0);
 	}
 }
+EXPORT_SYMBOL_GPL(md_bitmap_wait_behind_writes);
 
 void md_bitmap_destroy(struct mddev *mddev)
 {
diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
index 7acfe7c9dc8d..81fc100e7830 100644
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -1311,7 +1311,6 @@  static void raid1_read_request(struct mddev *mddev, struct bio *bio,
 	struct r1conf *conf = mddev->private;
 	struct raid1_info *mirror;
 	struct bio *read_bio;
-	struct bitmap *bitmap = mddev->bitmap;
 	const enum req_op op = bio_op(bio);
 	const blk_opf_t do_sync = bio->bi_opf & REQ_SYNC;
 	int max_sectors;
@@ -1377,15 +1376,13 @@  static void raid1_read_request(struct mddev *mddev, struct bio *bio,
 				    (unsigned long long)r1_bio->sector,
 				    mirror->rdev->bdev);
 
-	if (test_bit(WriteMostly, &mirror->rdev->flags) &&
-	    bitmap) {
+	if (test_bit(WriteMostly, &mirror->rdev->flags)) {
 		/*
 		 * Reading from a write-mostly device must take care not to
 		 * over-take any writes that are 'behind'
 		 */
 		mddev_add_trace_msg(mddev, "raid1 wait behind writes");
-		wait_event(bitmap->behind_wait,
-			   atomic_read(&bitmap->behind_writes) == 0);
+		md_bitmap_wait_behind_writes(mddev);
 	}
 
 	if (max_sectors < bio_sectors(bio)) {