md: remove redundant md_wakeup_thread()

On the one hand, mddev_unlock() will call md_wakeup_thread()
unconditionally; on the other hand, md_check_recovery() can't make
progress if 'reconfig_mutex' can't be grabbed. Hence, it really doesn't
make sense to wake up daemon thread while 'reconfig_mutex' is still
grabbed.

Remove all the md_wakup_thread() for 'mddev->thread' while
'reconfig_mtuex' is still grabbed.

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20231228125553.2697765-3-yukuai1@huaweicloud.com

diff --git a/drivers/md/md.c b/drivers/md/md.c
index 9b6b34ab9d1d40bc665c967ad8526cbc441e7cbf..0b132ee2672efd160a7774415c46ef86d17621d5 100644 (file)
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -2929,7 +2929,6 @@ static int add_bound_rdev(struct md_rdev *rdev)
                set_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
        set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
        md_new_event();
-       md_wakeup_thread(mddev->thread);
        return 0;
 }
 
@@ -3044,10 +3043,8 @@ state_store(struct md_rdev *rdev, const char *buf, size_t len)
 
                        if (err == 0) {
                                md_kick_rdev_from_array(rdev);
-                               if (mddev->pers) {
+                               if (mddev->pers)
                                        set_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags);
-                                       md_wakeup_thread(mddev->thread);
-                               }
                                md_new_event();
                        }
                }
@@ -3077,7 +3074,6 @@ state_store(struct md_rdev *rdev, const char *buf, size_t len)
                clear_bit(BlockedBadBlocks, &rdev->flags);
                wake_up(&rdev->blocked_wait);
                set_bit(MD_RECOVERY_NEEDED, &rdev->mddev->recovery);
-               md_wakeup_thread(rdev->mddev->thread);
 
                err = 0;
        } else if (cmd_match(buf, "insync") && rdev->raid_disk == -1) {
@@ -3115,7 +3111,6 @@ state_store(struct md_rdev *rdev, const char *buf, size_t len)
                    !test_bit(Replacement, &rdev->flags))
                        set_bit(WantReplacement, &rdev->flags);
                set_bit(MD_RECOVERY_NEEDED, &rdev->mddev->recovery);
-               md_wakeup_thread(rdev->mddev->thread);
                err = 0;
        } else if (cmd_match(buf, "-want_replacement")) {
                /* Clearing 'want_replacement' is always allowed.
@@ -3245,7 +3240,6 @@ slot_store(struct md_rdev *rdev, const char *buf, size_t len)
                if (rdev->raid_disk >= 0)
                        return -EBUSY;
                set_bit(MD_RECOVERY_NEEDED, &rdev->mddev->recovery);
-               md_wakeup_thread(rdev->mddev->thread);
        } else if (rdev->mddev->pers) {
                /* Activating a spare .. or possibly reactivating
                 * if we ever get bitmaps working here.
@@ -6186,7 +6180,6 @@ int do_md_run(struct mddev *mddev)
        /* run start up tasks that require md_thread */
        md_start(mddev);
 
-       md_wakeup_thread(mddev->thread);
        md_wakeup_thread(mddev->sync_thread); /* possibly kick off a reshape */
 
        set_capacity_and_notify(mddev->gendisk, mddev->array_sectors);
@@ -6207,7 +6200,6 @@ int md_start(struct mddev *mddev)
 
        if (mddev->pers->start) {
                set_bit(MD_RECOVERY_WAIT, &mddev->recovery);
-               md_wakeup_thread(mddev->thread);
                ret = mddev->pers->start(mddev);
                clear_bit(MD_RECOVERY_WAIT, &mddev->recovery);
                md_wakeup_thread(mddev->sync_thread);
@@ -6252,7 +6244,6 @@ static int restart_array(struct mddev *mddev)
        pr_debug("md: %s switched to read-write mode.\n", mdname(mddev));
        /* Kick recovery or resync if necessary */
        set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
-       md_wakeup_thread(mddev->thread);
        md_wakeup_thread(mddev->sync_thread);
        sysfs_notify_dirent_safe(mddev->sysfs_state);
        return 0;
@@ -6396,7 +6387,6 @@ static int md_set_readonly(struct mddev *mddev, struct block_device *bdev)
        if (!test_bit(MD_RECOVERY_FROZEN, &mddev->recovery)) {
                did_freeze = 1;
                set_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
-               md_wakeup_thread(mddev->thread);
        }
 
        stop_sync_thread(mddev, false, false);
@@ -6428,7 +6418,6 @@ out:
        if ((mddev->pers && !err) || did_freeze) {
                clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
                set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
-               md_wakeup_thread(mddev->thread);
                sysfs_notify_dirent_safe(mddev->sysfs_state);
        }
 
@@ -6450,7 +6439,6 @@ static int do_md_stop(struct mddev *mddev, int mode,
        if (!test_bit(MD_RECOVERY_FROZEN, &mddev->recovery)) {
                did_freeze = 1;
                set_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
-               md_wakeup_thread(mddev->thread);
        }
 
        stop_sync_thread(mddev, true, false);
@@ -6464,7 +6452,6 @@ static int do_md_stop(struct mddev *mddev, int mode,
                if (did_freeze) {
                        clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
                        set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
-                       md_wakeup_thread(mddev->thread);
                }
                return -EBUSY;
        }
@@ -7005,9 +6992,7 @@ kick_rdev:
 
        md_kick_rdev_from_array(rdev);
        set_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags);
-       if (mddev->thread)
-               md_wakeup_thread(mddev->thread);
-       else
+       if (!mddev->thread)
                md_update_sb(mddev, 1);
        md_new_event();
 
@@ -7089,7 +7074,6 @@ static int hot_add_disk(struct mddev *mddev, dev_t dev)
         * array immediately.
         */
        set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
-       md_wakeup_thread(mddev->thread);
        md_new_event();
        return 0;