md/raid1-10: factor out a helper to add bio to plug

The code in raid1 and raid10 is identical, prepare to limit the number
of plugged bios.

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20230529131106.2123367-3-yukuai1@huaweicloud.com

diff --git a/drivers/md/raid1-10.c b/drivers/md/raid1-10.c
index cd349e6..76cff92 100644 (file)
--- a/drivers/md/raid1-10.c
+++ b/drivers/md/raid1-10.c
@@ -110,3 +110,19 @@ static void md_bio_reset_resync_pages(struct bio *bio, struct resync_pages *rp,
                size -= len;
        } while (idx++ < RESYNC_PAGES && size > 0);
 }
+
+static inline bool raid1_add_bio_to_plug(struct mddev *mddev, struct bio *bio,
+                                     blk_plug_cb_fn unplug)
+{
+       struct raid1_plug_cb *plug = NULL;
+       struct blk_plug_cb *cb = blk_check_plugged(unplug, mddev,
+                                                  sizeof(*plug));
+
+       if (!cb)
+               return false;
+
+       plug = container_of(cb, struct raid1_plug_cb, cb);
+       bio_list_add(&plug->pending, bio);
+
+       return true;
+}

diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
index 220f6ce..92180f3 100644 (file)
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -1346,8 +1346,6 @@ static void raid1_write_request(struct mddev *mddev, struct bio *bio,
        struct bitmap *bitmap = mddev->bitmap;
        unsigned long flags;
        struct md_rdev *blocked_rdev;
-       struct blk_plug_cb *cb;
-       struct raid1_plug_cb *plug = NULL;
        int first_clone;
        int max_sectors;
        bool write_behind = false;
@@ -1576,15 +1574,7 @@ static void raid1_write_request(struct mddev *mddev, struct bio *bio,
                                              r1_bio->sector);
                /* flush_pending_writes() needs access to the rdev so...*/
                mbio->bi_bdev = (void *)rdev;
-
-               cb = blk_check_plugged(raid1_unplug, mddev, sizeof(*plug));
-               if (cb)
-                       plug = container_of(cb, struct raid1_plug_cb, cb);
-               else
-                       plug = NULL;
-               if (plug) {
-                       bio_list_add(&plug->pending, mbio);
-               } else {
+               if (!raid1_add_bio_to_plug(mddev, mbio, raid1_unplug)) {
                        spin_lock_irqsave(&conf->device_lock, flags);
                        bio_list_add(&conf->pending_bio_list, mbio);
                        spin_unlock_irqrestore(&conf->device_lock, flags);

diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c
index 09017a4..b8223da 100644 (file)
--- a/drivers/md/raid10.c
+++ b/drivers/md/raid10.c
@@ -1295,8 +1295,6 @@ static void raid10_write_one_disk(struct mddev *mddev, struct r10bio *r10_bio,
        const blk_opf_t do_sync = bio->bi_opf & REQ_SYNC;
        const blk_opf_t do_fua = bio->bi_opf & REQ_FUA;
        unsigned long flags;
-       struct blk_plug_cb *cb;
-       struct raid1_plug_cb *plug = NULL;
        struct r10conf *conf = mddev->private;
        struct md_rdev *rdev;
        int devnum = r10_bio->devs[n_copy].devnum;
@@ -1336,14 +1334,7 @@ static void raid10_write_one_disk(struct mddev *mddev, struct r10bio *r10_bio,
 
        atomic_inc(&r10_bio->remaining);
 
-       cb = blk_check_plugged(raid10_unplug, mddev, sizeof(*plug));
-       if (cb)
-               plug = container_of(cb, struct raid1_plug_cb, cb);
-       else
-               plug = NULL;
-       if (plug) {
-               bio_list_add(&plug->pending, mbio);
-       } else {
+       if (!raid1_add_bio_to_plug(mddev, mbio, raid10_unplug)) {
                spin_lock_irqsave(&conf->device_lock, flags);
                bio_list_add(&conf->pending_bio_list, mbio);
                spin_unlock_irqrestore(&conf->device_lock, flags);