summaryrefslogtreecommitdiffstats
path: root/xlators/mgmt/glusterd/src/glusterd-mgmt.c
diff options
context:
space:
mode:
Diffstat (limited to 'xlators/mgmt/glusterd/src/glusterd-mgmt.c')
-rw-r--r--xlators/mgmt/glusterd/src/glusterd-mgmt.c319
1 files changed, 211 insertions, 108 deletions
diff --git a/xlators/mgmt/glusterd/src/glusterd-mgmt.c b/xlators/mgmt/glusterd/src/glusterd-mgmt.c
index 2a34c78b35b..4e4dd047281 100644
--- a/xlators/mgmt/glusterd/src/glusterd-mgmt.c
+++ b/xlators/mgmt/glusterd/src/glusterd-mgmt.c
@@ -383,9 +383,9 @@ out:
int
glusterd_mgmt_v3_initiate_lockdown (glusterd_op_t op, dict_t *dict,
- char **op_errstr, int npeers,
+ char **op_errstr,
gf_boolean_t *is_acquired,
- struct cds_list_head *peers)
+ uint64_t txn_generation)
{
char *volname = NULL;
glusterd_peerinfo_t *peerinfo = NULL;
@@ -394,9 +394,13 @@ glusterd_mgmt_v3_initiate_lockdown (glusterd_op_t op, dict_t *dict,
struct syncargs args = {0};
uuid_t peer_uuid = {0};
xlator_t *this = NULL;
+ glusterd_conf_t *conf = NULL;
this = THIS;
GF_ASSERT (this);
+ conf = this->private;
+ GF_ASSERT (conf);
+
GF_ASSERT (dict);
GF_ASSERT (op_errstr);
GF_ASSERT (is_acquired);
@@ -411,20 +415,36 @@ glusterd_mgmt_v3_initiate_lockdown (glusterd_op_t op, dict_t *dict,
*is_acquired = _gf_true;
- if (!npeers) {
- ret = 0;
- goto out;
- }
-
/* Sending mgmt_v3 lock req to other nodes in the cluster */
gd_syncargs_init (&args, NULL);
synctask_barrier_init((&args));
peer_cnt = 0;
- list_for_each_local_xaction_peers (peerinfo, peers) {
+
+ rcu_read_lock ();
+ cds_list_for_each_entry_rcu (peerinfo, &conf->peers, uuid_list) {
+ /* Only send requests to peers who were available before the
+ * transaction started
+ */
+ if (peerinfo->generation > txn_generation)
+ continue;
+
+ if (!peerinfo->connected)
+ continue;
+ if (op != GD_OP_SYNC_VOLUME &&
+ peerinfo->state.state != GD_FRIEND_STATE_BEFRIENDED)
+ continue;
+
gd_mgmt_v3_lock (op, dict, peerinfo, &args,
MY_UUID, peer_uuid);
peer_cnt++;
}
+ rcu_read_unlock ();
+
+ if (0 == peer_cnt) {
+ ret = 0;
+ goto out;
+ }
+
gd_synctask_barrier_wait((&args), peer_cnt);
if (args.errstr)
@@ -633,8 +653,8 @@ out:
int
glusterd_mgmt_v3_pre_validate (glusterd_op_t op, dict_t *req_dict,
- char **op_errstr, int npeers,
- struct cds_list_head *peers)
+ char **op_errstr,
+ uint64_t txn_generation)
{
int32_t ret = -1;
int32_t peer_cnt = 0;
@@ -643,9 +663,13 @@ glusterd_mgmt_v3_pre_validate (glusterd_op_t op, dict_t *req_dict,
struct syncargs args = {0};
uuid_t peer_uuid = {0};
xlator_t *this = NULL;
+ glusterd_conf_t *conf = NULL;
this = THIS;
GF_ASSERT (this);
+ conf = this->private;
+ GF_ASSERT (conf);
+
GF_ASSERT (req_dict);
GF_ASSERT (op_errstr);
@@ -691,20 +715,36 @@ glusterd_mgmt_v3_pre_validate (glusterd_op_t op, dict_t *req_dict,
dict_unref (rsp_dict);
rsp_dict = NULL;
- if (!npeers) {
- ret = 0;
- goto out;
- }
-
/* Sending Pre Validation req to other nodes in the cluster */
gd_syncargs_init (&args, req_dict);
synctask_barrier_init((&args));
peer_cnt = 0;
- list_for_each_local_xaction_peers (peerinfo, peers) {
+
+ rcu_read_lock ();
+ cds_list_for_each_entry_rcu (peerinfo, &conf->peers, uuid_list) {
+ /* Only send requests to peers who were available before the
+ * transaction started
+ */
+ if (peerinfo->generation > txn_generation)
+ continue;
+
+ if (!peerinfo->connected)
+ continue;
+ if (op != GD_OP_SYNC_VOLUME &&
+ peerinfo->state.state != GD_FRIEND_STATE_BEFRIENDED)
+ continue;
+
gd_mgmt_v3_pre_validate_req (op, req_dict, peerinfo, &args,
MY_UUID, peer_uuid);
peer_cnt++;
}
+ rcu_read_unlock ();
+
+ if (0 == peer_cnt) {
+ ret = 0;
+ goto out;
+ }
+
gd_synctask_barrier_wait((&args), peer_cnt);
if (args.op_ret) {
@@ -865,9 +905,8 @@ out:
}
int
-glusterd_mgmt_v3_brick_op (glusterd_op_t op, dict_t *req_dict,
- char **op_errstr, int npeers,
- struct cds_list_head *peers)
+glusterd_mgmt_v3_brick_op (glusterd_op_t op, dict_t *req_dict, char **op_errstr,
+ uint64_t txn_generation)
{
int32_t ret = -1;
int32_t peer_cnt = 0;
@@ -876,9 +915,13 @@ glusterd_mgmt_v3_brick_op (glusterd_op_t op, dict_t *req_dict,
struct syncargs args = {0};
uuid_t peer_uuid = {0};
xlator_t *this = NULL;
+ glusterd_conf_t *conf = NULL;
this = THIS;
GF_ASSERT (this);
+ conf = this->private;
+ GF_ASSERT (conf);
+
GF_ASSERT (req_dict);
GF_ASSERT (op_errstr);
@@ -915,20 +958,36 @@ glusterd_mgmt_v3_brick_op (glusterd_op_t op, dict_t *req_dict,
dict_unref (rsp_dict);
rsp_dict = NULL;
- if (!npeers) {
- ret = 0;
- goto out;
- }
-
/* Sending brick op req to other nodes in the cluster */
gd_syncargs_init (&args, NULL);
synctask_barrier_init((&args));
peer_cnt = 0;
- list_for_each_local_xaction_peers (peerinfo, peers) {
+
+ rcu_read_lock ();
+ cds_list_for_each_entry_rcu (peerinfo, &conf->peers, uuid_list) {
+ /* Only send requests to peers who were available before the
+ * transaction started
+ */
+ if (peerinfo->generation > txn_generation)
+ continue;
+
+ if (!peerinfo->connected)
+ continue;
+ if (op != GD_OP_SYNC_VOLUME &&
+ peerinfo->state.state != GD_FRIEND_STATE_BEFRIENDED)
+ continue;
+
gd_mgmt_v3_brick_op_req (op, req_dict, peerinfo, &args,
MY_UUID, peer_uuid);
peer_cnt++;
}
+ rcu_read_unlock ();
+
+ if (0 == peer_cnt) {
+ ret = 0;
+ goto out;
+ }
+
gd_synctask_barrier_wait((&args), peer_cnt);
if (args.op_ret) {
@@ -1084,9 +1143,8 @@ out:
}
int
-glusterd_mgmt_v3_commit (glusterd_op_t op, dict_t *op_ctx,
- dict_t *req_dict, char **op_errstr,
- int npeers, struct cds_list_head *peers)
+glusterd_mgmt_v3_commit (glusterd_op_t op, dict_t *op_ctx, dict_t *req_dict,
+ char **op_errstr, uint64_t txn_generation)
{
int32_t ret = -1;
int32_t peer_cnt = 0;
@@ -1095,9 +1153,13 @@ glusterd_mgmt_v3_commit (glusterd_op_t op, dict_t *op_ctx,
struct syncargs args = {0};
uuid_t peer_uuid = {0};
xlator_t *this = NULL;
+ glusterd_conf_t *conf = NULL;
this = THIS;
GF_ASSERT (this);
+ conf = this->private;
+ GF_ASSERT (conf);
+
GF_ASSERT (op_ctx);
GF_ASSERT (req_dict);
GF_ASSERT (op_errstr);
@@ -1144,20 +1206,36 @@ glusterd_mgmt_v3_commit (glusterd_op_t op, dict_t *op_ctx,
dict_unref (rsp_dict);
rsp_dict = NULL;
- if (!npeers) {
- ret = 0;
- goto out;
- }
-
/* Sending commit req to other nodes in the cluster */
gd_syncargs_init (&args, op_ctx);
synctask_barrier_init((&args));
peer_cnt = 0;
- list_for_each_local_xaction_peers (peerinfo, peers) {
+
+ rcu_read_lock ();
+ cds_list_for_each_entry_rcu (peerinfo, &conf->peers, uuid_list) {
+ /* Only send requests to peers who were available before the
+ * transaction started
+ */
+ if (peerinfo->generation > txn_generation)
+ continue;
+
+ if (!peerinfo->connected)
+ continue;
+ if (op != GD_OP_SYNC_VOLUME &&
+ peerinfo->state.state != GD_FRIEND_STATE_BEFRIENDED)
+ continue;
+
gd_mgmt_v3_commit_req (op, req_dict, peerinfo, &args,
MY_UUID, peer_uuid);
peer_cnt++;
}
+ rcu_read_unlock ();
+
+ if (0 == peer_cnt) {
+ ret = 0;
+ goto out;
+ }
+
gd_synctask_barrier_wait((&args), peer_cnt);
if (args.op_ret) {
@@ -1282,8 +1360,8 @@ out:
int
glusterd_mgmt_v3_post_validate (glusterd_op_t op, int32_t op_ret, dict_t *dict,
- dict_t *req_dict, char **op_errstr, int npeers,
- struct cds_list_head *peers)
+ dict_t *req_dict, char **op_errstr,
+ uint64_t txn_generation)
{
int32_t ret = -1;
int32_t peer_cnt = 0;
@@ -1292,9 +1370,13 @@ glusterd_mgmt_v3_post_validate (glusterd_op_t op, int32_t op_ret, dict_t *dict,
struct syncargs args = {0};
uuid_t peer_uuid = {0};
xlator_t *this = NULL;
+ glusterd_conf_t *conf = NULL;
this = THIS;
GF_ASSERT (this);
+ conf = this->private;
+ GF_ASSERT (conf);
+
GF_ASSERT (dict);
GF_VALIDATE_OR_GOTO (this->name, req_dict, out);
GF_ASSERT (op_errstr);
@@ -1335,20 +1417,36 @@ glusterd_mgmt_v3_post_validate (glusterd_op_t op, int32_t op_ret, dict_t *dict,
dict_unref (rsp_dict);
rsp_dict = NULL;
- if (!npeers) {
- ret = 0;
- goto out;
- }
-
/* Sending Post Validation req to other nodes in the cluster */
gd_syncargs_init (&args, req_dict);
synctask_barrier_init((&args));
peer_cnt = 0;
- list_for_each_local_xaction_peers (peerinfo, peers) {
+
+ rcu_read_lock ();
+ cds_list_for_each_entry_rcu (peerinfo, &conf->peers, uuid_list) {
+ /* Only send requests to peers who were available before the
+ * transaction started
+ */
+ if (peerinfo->generation > txn_generation)
+ continue;
+
+ if (!peerinfo->connected)
+ continue;
+ if (op != GD_OP_SYNC_VOLUME &&
+ peerinfo->state.state != GD_FRIEND_STATE_BEFRIENDED)
+ continue;
+
gd_mgmt_v3_post_validate_req (op, op_ret, req_dict, peerinfo,
&args, MY_UUID, peer_uuid);
peer_cnt++;
}
+ rcu_read_unlock ();
+
+ if (0 == peer_cnt) {
+ ret = 0;
+ goto out;
+ }
+
gd_synctask_barrier_wait((&args), peer_cnt);
if (args.op_ret) {
@@ -1468,11 +1566,10 @@ out:
}
int
-glusterd_mgmt_v3_release_peer_locks (glusterd_op_t op,
- dict_t *dict, int32_t op_ret,
- char **op_errstr, int npeers,
+glusterd_mgmt_v3_release_peer_locks (glusterd_op_t op, dict_t *dict,
+ int32_t op_ret, char **op_errstr,
gf_boolean_t is_acquired,
- struct cds_list_head *peers)
+ uint64_t txn_generation)
{
int32_t ret = -1;
int32_t peer_cnt = 0;
@@ -1480,9 +1577,13 @@ glusterd_mgmt_v3_release_peer_locks (glusterd_op_t op,
xlator_t *this = NULL;
glusterd_peerinfo_t *peerinfo = NULL;
struct syncargs args = {0};
+ glusterd_conf_t *conf = NULL;
this = THIS;
GF_ASSERT (this);
+ conf = this->private;
+ GF_ASSERT (conf);
+
GF_ASSERT (dict);
GF_ASSERT (op_errstr);
@@ -1491,20 +1592,36 @@ glusterd_mgmt_v3_release_peer_locks (glusterd_op_t op,
if (!is_acquired)
goto out;
- if (!npeers) {
- ret = 0;
- goto out;
- }
-
/* Sending mgmt_v3 unlock req to other nodes in the cluster */
gd_syncargs_init (&args, NULL);
synctask_barrier_init((&args));
peer_cnt = 0;
- list_for_each_local_xaction_peers (peerinfo, peers) {
+
+ rcu_read_lock ();
+ cds_list_for_each_entry_rcu (peerinfo, &conf->peers, uuid_list) {
+ /* Only send requests to peers who were available before the
+ * transaction started
+ */
+ if (peerinfo->generation > txn_generation)
+ continue;
+
+ if (!peerinfo->connected)
+ continue;
+ if (op != GD_OP_SYNC_VOLUME &&
+ peerinfo->state.state != GD_FRIEND_STATE_BEFRIENDED)
+ continue;
+
gd_mgmt_v3_unlock (op, dict, peerinfo, &args,
MY_UUID, peer_uuid);
peer_cnt++;
}
+ rcu_read_unlock ();
+
+ if (0 == peer_cnt) {
+ ret = 0;
+ goto out;
+ }
+
gd_synctask_barrier_wait((&args), peer_cnt);
if (args.op_ret) {
@@ -1530,7 +1647,6 @@ glusterd_mgmt_v3_initiate_all_phases (rpcsvc_request_t *req, glusterd_op_t op,
{
int32_t ret = -1;
int32_t op_ret = -1;
- int32_t npeers = 0;
dict_t *req_dict = NULL;
dict_t *tmp_dict = NULL;
glusterd_conf_t *conf = NULL;
@@ -1538,7 +1654,7 @@ glusterd_mgmt_v3_initiate_all_phases (rpcsvc_request_t *req, glusterd_op_t op,
xlator_t *this = NULL;
gf_boolean_t is_acquired = _gf_false;
uuid_t *originator_uuid = NULL;
- struct cds_list_head xaction_peers = {0,};
+ uint64_t txn_generation = 0;
this = THIS;
GF_ASSERT (this);
@@ -1547,14 +1663,14 @@ glusterd_mgmt_v3_initiate_all_phases (rpcsvc_request_t *req, glusterd_op_t op,
conf = this->private;
GF_ASSERT (conf);
- CDS_INIT_LIST_HEAD (&xaction_peers);
- npeers = gd_build_local_xaction_peers_list (&conf->peers,
- &xaction_peers, op);
- if (npeers == -1) {
- gf_log (this->name, GF_LOG_ERROR, "building local peers list "
- "failed");
- goto rsp;
- }
+ /* Save the peer list generation */
+ txn_generation = conf->generation;
+ cmm_smp_rmb ();
+ /* This read memory barrier makes sure that this assignment happens here
+ * only and is not reordered and optimized by either the compiler or the
+ * processor.
+ */
+
/* Save the MY_UUID as the originator_uuid. This originator_uuid
* will be used by is_origin_glusterd() to determine if a node
@@ -1594,8 +1710,7 @@ glusterd_mgmt_v3_initiate_all_phases (rpcsvc_request_t *req, glusterd_op_t op,
/* LOCKDOWN PHASE - Acquire mgmt_v3 locks */
ret = glusterd_mgmt_v3_initiate_lockdown (op, dict, &op_errstr,
- npeers, &is_acquired,
- &xaction_peers);
+ &is_acquired, txn_generation);
if (ret) {
gf_log (this->name, GF_LOG_ERROR, "mgmt_v3 lockdown failed.");
goto out;
@@ -1612,17 +1727,16 @@ glusterd_mgmt_v3_initiate_all_phases (rpcsvc_request_t *req, glusterd_op_t op,
}
/* PRE-COMMIT VALIDATE PHASE */
- ret = glusterd_mgmt_v3_pre_validate (op, req_dict,
- &op_errstr, npeers,
- &xaction_peers);
+ ret = glusterd_mgmt_v3_pre_validate (op, req_dict, &op_errstr,
+ txn_generation);
if (ret) {
gf_log (this->name, GF_LOG_ERROR, "Pre Validation Failed");
goto out;
}
/* COMMIT OP PHASE */
- ret = glusterd_mgmt_v3_commit (op, dict, req_dict,
- &op_errstr, npeers, &xaction_peers);
+ ret = glusterd_mgmt_v3_commit (op, dict, req_dict, &op_errstr,
+ txn_generation);
if (ret) {
gf_log (this->name, GF_LOG_ERROR, "Commit Op Failed");
goto out;
@@ -1633,9 +1747,8 @@ glusterd_mgmt_v3_initiate_all_phases (rpcsvc_request_t *req, glusterd_op_t op,
commands other than snapshot. So as of now, I am
sending 0 (op_ret as 0).
*/
- ret = glusterd_mgmt_v3_post_validate (op, 0, dict, req_dict,
- &op_errstr, npeers,
- &xaction_peers);
+ ret = glusterd_mgmt_v3_post_validate (op, 0, dict, req_dict, &op_errstr,
+ txn_generation);
if (ret) {
gf_log (this->name, GF_LOG_ERROR, "Post Validation Failed");
goto out;
@@ -1645,10 +1758,9 @@ glusterd_mgmt_v3_initiate_all_phases (rpcsvc_request_t *req, glusterd_op_t op,
out:
op_ret = ret;
/* UNLOCK PHASE FOR PEERS*/
- (void) glusterd_mgmt_v3_release_peer_locks (op, dict,
- op_ret, &op_errstr,
- npeers, is_acquired,
- &xaction_peers);
+ (void) glusterd_mgmt_v3_release_peer_locks (op, dict, op_ret,
+ &op_errstr, is_acquired,
+ txn_generation);
/* LOCAL VOLUME(S) UNLOCK */
if (is_acquired) {
@@ -1660,12 +1772,10 @@ out:
op_ret = ret;
}
}
-rsp:
+
/* SEND CLI RESPONSE */
glusterd_op_send_cli_response (op, op_ret, 0, req, dict, op_errstr);
- gd_cleanup_local_xaction_peers_list (&xaction_peers);
-
if (req_dict)
dict_unref (req_dict);
@@ -1748,7 +1858,6 @@ glusterd_mgmt_v3_initiate_snap_phases (rpcsvc_request_t *req, glusterd_op_t op,
{
int32_t ret = -1;
int32_t op_ret = -1;
- int32_t npeers = 0;
dict_t *req_dict = NULL;
dict_t *tmp_dict = NULL;
glusterd_conf_t *conf = NULL;
@@ -1758,7 +1867,7 @@ glusterd_mgmt_v3_initiate_snap_phases (rpcsvc_request_t *req, glusterd_op_t op,
uuid_t *originator_uuid = NULL;
gf_boolean_t success = _gf_false;
char *cli_errstr = NULL;
- struct cds_list_head xaction_peers = {0,};
+ uint64_t txn_generation = 0;
this = THIS;
GF_ASSERT (this);
@@ -1767,14 +1876,13 @@ glusterd_mgmt_v3_initiate_snap_phases (rpcsvc_request_t *req, glusterd_op_t op,
conf = this->private;
GF_ASSERT (conf);
- CDS_INIT_LIST_HEAD (&xaction_peers);
- npeers = gd_build_local_xaction_peers_list (&conf->peers,
- &xaction_peers, op);
- if (npeers == -1) {
- gf_log (this->name, GF_LOG_ERROR, "building local peers list "
- "failed");
- goto rsp;
- }
+ /* Save the peer list generation */
+ txn_generation = conf->generation;
+ cmm_smp_rmb ();
+ /* This read memory barrier makes sure that this assignment happens here
+ * only and is not reordered and optimized by either the compiler or the
+ * processor.
+ */
/* Save the MY_UUID as the originator_uuid. This originator_uuid
* will be used by is_origin_glusterd() to determine if a node
@@ -1814,8 +1922,7 @@ glusterd_mgmt_v3_initiate_snap_phases (rpcsvc_request_t *req, glusterd_op_t op,
/* LOCKDOWN PHASE - Acquire mgmt_v3 locks */
ret = glusterd_mgmt_v3_initiate_lockdown (op, dict, &op_errstr,
- npeers, &is_acquired,
- &xaction_peers);
+ &is_acquired, txn_generation);
if (ret) {
gf_log (this->name, GF_LOG_ERROR, "mgmt_v3 lockdown failed.");
goto out;
@@ -1832,8 +1939,8 @@ glusterd_mgmt_v3_initiate_snap_phases (rpcsvc_request_t *req, glusterd_op_t op,
}
/* PRE-COMMIT VALIDATE PHASE */
- ret = glusterd_mgmt_v3_pre_validate (op, req_dict,
- &op_errstr, npeers, &xaction_peers);
+ ret = glusterd_mgmt_v3_pre_validate (op, req_dict, &op_errstr,
+ txn_generation);
if (ret) {
gf_log (this->name, GF_LOG_ERROR, "Pre Validation Failed");
goto out;
@@ -1857,8 +1964,8 @@ glusterd_mgmt_v3_initiate_snap_phases (rpcsvc_request_t *req, glusterd_op_t op,
goto out;
}
- ret = glusterd_mgmt_v3_brick_op (op, req_dict,
- &op_errstr, npeers, &xaction_peers);
+ ret = glusterd_mgmt_v3_brick_op (op, req_dict, &op_errstr,
+ txn_generation);
if (ret) {
gf_log (this->name, GF_LOG_ERROR, "Brick Ops Failed");
goto unbarrier;
@@ -1888,8 +1995,8 @@ glusterd_mgmt_v3_initiate_snap_phases (rpcsvc_request_t *req, glusterd_op_t op,
goto unbarrier;
}
- ret = glusterd_mgmt_v3_commit (op, dict, req_dict,
- &op_errstr, npeers, &xaction_peers);
+ ret = glusterd_mgmt_v3_commit (op, dict, req_dict, &op_errstr,
+ txn_generation);
if (ret) {
gf_log (this->name, GF_LOG_ERROR, "Commit Op Failed");
/* If the main op fails, we should save the error string.
@@ -1914,8 +2021,8 @@ unbarrier:
goto out;
}
- ret = glusterd_mgmt_v3_brick_op (op, req_dict,
- &op_errstr, npeers, &xaction_peers);
+ ret = glusterd_mgmt_v3_brick_op (op, req_dict, &op_errstr,
+ txn_generation);
if (ret) {
gf_log (this->name, GF_LOG_ERROR, "Brick Ops Failed");
@@ -1943,18 +2050,16 @@ out:
/* POST-COMMIT VALIDATE PHASE */
ret = glusterd_mgmt_v3_post_validate (op, op_ret, dict, req_dict,
- &op_errstr, npeers,
- &xaction_peers);
+ &op_errstr, txn_generation);
if (ret) {
gf_log (this->name, GF_LOG_ERROR, "Post Validation Failed");
op_ret = -1;
}
/* UNLOCK PHASE FOR PEERS*/
- (void) glusterd_mgmt_v3_release_peer_locks (op, dict,
- op_ret, &op_errstr,
- npeers, is_acquired,
- &xaction_peers);
+ (void) glusterd_mgmt_v3_release_peer_locks (op, dict, op_ret,
+ &op_errstr, is_acquired,
+ txn_generation);
/* If the commit op (snapshot taking) failed, then the error is stored
in cli_errstr and unbarrier is called. Suppose, if unbarrier also
@@ -1978,12 +2083,10 @@ out:
op_ret = ret;
}
}
-rsp:
+
/* SEND CLI RESPONSE */
glusterd_op_send_cli_response (op, op_ret, 0, req, dict, op_errstr);
- gd_cleanup_local_xaction_peers_list (&xaction_peers);
-
if (req_dict)
dict_unref (req_dict);
generated by cgit (git 2.34.1) at 2024-05-22 03:33:35 +0000