md-cluster: update comments for MD_CLUSTER_SEND_LOCKED_ALREADY (e19508fa) · Commits · 戴 / test

drivers/md/md-cluster.c

+18 −5

Original line number	Diff line number	Diff line
		@@ -53,11 +53,12 @@ struct resync_info {
		* accomodate lock and hold. See next comment.
		*/
		#define MD_CLUSTER_SEND_LOCK 4
		/* If cluster operations must lock the communication channel,
		* so as to perform extra operations (and no other operation
		* is allowed on the MD, such as adding a disk. Token needs
		* to be locked and held until the operation completes with
		* a md_update_sb(), which would eventually release the lock.
		/* If cluster operations (such as adding a disk) must lock the
		* communication channel, so as to perform extra operations
		* (update metadata) and no other operation is allowed on the
		* MD. Token needs to be locked and held until the operation
		* completes witha md_update_sb(), which would eventually release
		* the lock.
		*/
		#define MD_CLUSTER_SEND_LOCKED_ALREADY 5

		@@ -1021,6 +1022,18 @@ static int add_new_disk(struct mddev mddev, struct md_rdev rdev)
		unlock_comm(cinfo);
		else {
		dlm_lock_sync(cinfo->no_new_dev_lockres, DLM_LOCK_CR);
		/* Since MD_CHANGE_DEVS will be set in add_bound_rdev which
		* will run soon after add_new_disk, the below path will be
		* invoked:
		* md_wakeup_thread(mddev->thread)
		* -> conf->thread (raid1d)
		* -> md_check_recovery -> md_update_sb
		* -> metadata_update_start/finish
		* MD_CLUSTER_SEND_LOCKED_ALREADY will be cleared eventually.
		*
		* For other failure cases, metadata_update_cancel and
		* add_new_disk_cancel also clear below bit as well.
		* */
		set_bit(MD_CLUSTER_SEND_LOCKED_ALREADY, &cinfo->state);
		wake_up(&cinfo->wait);
		}