From: Goldwyn Rodrigues <rgoldwyn@xxxxxxxx>
Resync or recovery must be performed by only one node at a time.
A DLM lock resource, resync_lockres provides the mutual exclusion
so that only one node performs the recovery/resync at a time.
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@xxxxxxxx>
---
drivers/md/md-cluster.c | 29 +++++++++++++++++++++++++++++
drivers/md/md-cluster.h | 1 +
drivers/md/md.c | 17 ++++++++++++++---
3 files changed, 44 insertions(+), 3 deletions(-)
diff --git a/drivers/md/md-cluster.c b/drivers/md/md-cluster.c
index 4645a93..17f24bf 100644
--- a/drivers/md/md-cluster.c
+++ b/drivers/md/md-cluster.c
@@ -46,6 +46,7 @@ struct resync_info {
#define MD_CLUSTER_WAITING_FOR_NEWDISK 1
#define MD_CLUSTER_SUSPEND_READ_BALANCING 2
#define MD_CLUSTER_BEGIN_JOIN_CLUSTER 3
+#define MD_CLUSTER_RECOVERY_NEEDED 4
struct md_cluster_info {
@@ -55,6 +56,7 @@ struct md_cluster_info {
struct completion completion;
struct mutex sb_mutex;
struct dlm_lock_resource *bitmap_lockres;
+ struct dlm_lock_resource *resync_lockres;
struct list_head suspend_list;
spinlock_t suspend_lock;
struct md_thread *recovery_thread;
@@ -382,6 +384,8 @@ static void process_suspend_info(struct mddev *mddev,
if (!hi) {
remove_suspend_info(cinfo, slot);
+ if (test_and_clear_bit(MD_CLUSTER_RECOVERY_NEEDED, &cinfo->state))
+ set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
return;
}
s = kzalloc(sizeof(struct suspend_info), GFP_KERNEL);
@@ -755,6 +759,10 @@ static int join(struct mddev *mddev, int nodes)
goto err;
}
+ cinfo->resync_lockres = lockres_init(mddev, "resync", NULL, 0);
+ if (!cinfo->resync_lockres)
+ goto err;
+
ret = gather_all_resync_info(mddev, nodes);
if (ret)
goto err;
@@ -765,6 +773,7 @@ err:
lockres_free(cinfo->token_lockres);
lockres_free(cinfo->ack_lockres);
lockres_free(cinfo->no_new_dev_lockres);
+ lockres_free(cinfo->resync_lockres);
lockres_free(cinfo->bitmap_lockres);
if (cinfo->lockspace)
dlm_release_lockspace(cinfo->lockspace, 2);
@@ -838,6 +847,21 @@ static int metadata_update_cancel(struct mddev *mddev)
return dlm_unlock_sync(cinfo->token_lockres);
}
+static int resync_start(struct mddev *mddev)
+{
+ struct md_cluster_info *cinfo = mddev->cluster_info;
+ int ret = 0;
+ cinfo->resync_lockres->flags |= DLM_LKF_NOQUEUE;
+ ret = dlm_lock_sync(cinfo->resync_lockres, DLM_LOCK_EX);
+ if (ret) {
+ if (!test_bit(MD_CLUSTER_RECOVERY_NEEDED, &cinfo->state))
+ pr_info("md-cluster: Postponing recovery until other nodes finish recovery\n");
+ set_bit(MD_CLUSTER_RECOVERY_NEEDED, &cinfo->state);
+ } else
+ clear_bit(MD_CLUSTER_RECOVERY_NEEDED, &cinfo->state);
+ return ret;
+}
+
static int resync_info_update(struct mddev *mddev, sector_t lo, sector_t hi)
{
struct md_cluster_info *cinfo = mddev->cluster_info;
@@ -854,6 +878,10 @@ static int resync_info_update(struct mddev *mddev, sector_t lo, sector_t hi)
cmsg.slot = cpu_to_le32(slot);
cmsg.low = cpu_to_le64(lo);
cmsg.high = cpu_to_le64(hi);
+
+ /* Resync is finished */
+ if (hi == 0)
+ dlm_unlock_sync(cinfo->resync_lockres);
return sendmsg(cinfo, &cmsg);
}
@@ -972,6 +1000,7 @@ static struct md_cluster_operations cluster_ops = {
.join = join,
.leave = leave,
.slot_number = slot_number,
+ .resync_start = resync_start,
.resync_info_update = resync_info_update,
.metadata_update_start = metadata_update_start,
.metadata_update_finish = metadata_update_finish,
diff --git a/drivers/md/md-cluster.h b/drivers/md/md-cluster.h
index f5bdc0c..7061020 100644
--- a/drivers/md/md-cluster.h
+++ b/drivers/md/md-cluster.h
@@ -16,6 +16,7 @@ struct md_cluster_operations {
int (*metadata_update_start)(struct mddev *mddev);
int (*metadata_update_finish)(struct mddev *mddev);
int (*metadata_update_cancel)(struct mddev *mddev);
+ int (*resync_start)(struct mddev *mddev);
int (*area_resyncing)(struct mddev *mddev, int direction, sector_t lo, sector_t hi);
int (*add_new_disk_start)(struct mddev *mddev, struct md_rdev *rdev);
int (*add_new_disk_finish)(struct mddev *mddev);
diff --git a/drivers/md/md.c b/drivers/md/md.c
index 9abd070..75d14e3 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -8071,14 +8071,25 @@ no_add:
static void md_start_sync(struct work_struct *ws)
{
struct mddev *mddev = container_of(ws, struct mddev, del_work);
+ int ret = 0;
+
+ if (mddev_is_clustered(mddev)) {
+ ret = md_cluster_ops->resync_start(mddev);
+ if (ret) {
+ mddev->sync_thread = NULL;
+ goto out;
+ }
+ }
mddev->sync_thread = md_register_thread(md_do_sync,
mddev,
"resync");
+out:
if (!mddev->sync_thread) {
- printk(KERN_ERR "%s: could not start resync"
- " thread...\n",
- mdname(mddev));
+ if (!mddev_is_clustered(mddev))
+ printk(KERN_ERR "%s: could not start resync"
+ " thread...\n",
+ mdname(mddev));
/* leave the spares where they are, it shouldn't hurt */
clear_bit(MD_RECOVERY_SYNC, &mddev->recovery);
clear_bit(MD_RECOVERY_RESHAPE, &mddev->recovery);
--
1.8.5.6
--
To unsubscribe from this list: send the line "unsubscribe linux-raid" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
