glusterd: Volume locks and transaction specific opinfos

With this patch we are replacing the existing cluster-wide
lock taken on glusterds across the cluster, with volume locks
which are also taken on glusterds across the cluster, but are
volume specific. So with the volume locks we are able to perform
more than one gluster operation at the same time, as long as the
operations are being performed on different volumes.

We maintain a global list of volume-locks (using a dict for a list)
where the key is the volume name, and which saves the uuid of the
originator glusterd. These locks are held and released per volume
transaction.

In order to acheive multiple gluster operations occuring at the
same time, we also separate opinfos in the op-state-machine, as a
part of this patch. To do so, we generate a unique transaction-id
(uuid) per gluster transaction. An opinfo is then associated with
this transaction id, which is used throughout the transaction. We
maintain a run-time global list(using a dict) of transaction-ids,
and their respective opinfos to achieve this.

Upstream Feature Page: http://www.gluster.org/community/documentation/index.php/Features/glusterd-volume-locks

Change-Id: Iaad505a854bac8de8f83beec0357eb6cde3f7ea8
BUG: 1011470
Signed-off-by: Avra Sengupta <asengupt@redhat.com>
Reviewed-on: http://review.gluster.org/5994
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Vijay Bellur <vbellur@redhat.com>

1 files changed, 16 insertions, 5 deletions

diff --git a/xlators/mgmt/glusterd/src/glusterd-op-sm.h b/xlators/mgmt/glusterd/src/glusterd-op-sm.h
index 1125368cef9..53d4e2ff4b1 100644
--- a/xlators/mgmt/glusterd/src/glusterd-op-sm.h
+++ b/xlators/mgmt/glusterd/src/glusterd-op-sm.h
@@ -77,6 +77,7 @@ struct glusterd_op_sm_event_ {
         struct list_head                list;
         void                            *ctx;
         glusterd_op_sm_event_type_t     event;
+        uuid_t                          txn_id;
 };
 
 typedef struct glusterd_op_sm_event_ glusterd_op_sm_event_t;
@@ -119,6 +120,7 @@ typedef struct glusterd_op_log_filename_ctx_ glusterd_op_log_filename_ctx_t;
 
 struct glusterd_op_lock_ctx_ {
         uuid_t                  uuid;
+        dict_t                 *dict;
         rpcsvc_request_t        *req;
 };
 
@@ -180,7 +182,7 @@ glusterd_op_sm_new_event (glusterd_op_sm_event_type_t event_type,
                           glusterd_op_sm_event_t **new_event);
 int
 glusterd_op_sm_inject_event (glusterd_op_sm_event_type_t event_type,
-                             void *ctx);
+                             uuid_t *txn_id, void *ctx);
 
 int
 glusterd_op_sm_init ();
@@ -264,10 +266,7 @@ glusterd_op_init_commit_rsp_dict (glusterd_op_t op);
 
 void
 glusterd_op_modify_op_ctx (glusterd_op_t op, void *op_ctx);
-int32_t
-glusterd_op_init_ctx (glusterd_op_t op);
-int32_t
-glusterd_op_fini_ctx ();
+
 int32_t
 glusterd_volume_stats_read_perf (char *brick_path, int32_t blk_size,
                 int32_t blk_count, double *throughput, double *time);
@@ -296,4 +295,16 @@ int
 glusterd_is_valid_vg (glusterd_brickinfo_t *brick, int check_tag, char *msg);
 #endif
 
+int32_t
+glusterd_get_txn_opinfo (uuid_t *txn_id, glusterd_op_info_t  *opinfo);
+
+int32_t
+glusterd_set_txn_opinfo (uuid_t *txn_id, glusterd_op_info_t  *opinfo);
+
+int32_t
+glusterd_clear_txn_opinfo (uuid_t *txn_id);
+
+int32_t
+glusterd_generate_txn_id (dict_t *dict, uuid_t **txn_id);
+
 #endif