Merge branch '2.1' into develop

Documentation/Changelog.md

@@ -12,7 +12,7 @@
 * MySQL Monitor now has a failover mode.
 * Named Server Filter now supports wildcards for source option.
 * Binlog Server can now be configured to encrypt binlog files.
-* New filters, _cache, _ccrfilter_, _masking_, and _maxrows_ are introduced.
+* New filters, _cache_, _ccrfilter_, _insertstream_, _masking_, and _maxrows_ are introduced.
 
 For more details, please refer to:
 * [MariaDB MaxScale 2.1.0 Release Notes](Release-Notes/MaxScale-2.1.0-Release-Notes.md)

Documentation/Filters/CCRFilter.md

@@ -1,5 +1,7 @@
 # Consistent Critical Read Filter
 
+This filter was introduced in MariaDB MaxScale 2.1.
+
 ## Overview
 
 The Consistent Critical Read (CCR) filter allows consistent critical reads to be
@@ -68,3 +70,24 @@ An optional parameter that can be used to control which statements don't trigger
 the statement re-routing. This does the opposite of the _match_ parameter. The
 parameter value is a regular expression that is used to match against the SQL
 text. Only non-SELECT statements are inspected.
+
+## Example Configuration
+
+Here is a minimal filter configuration for the CCRFilter which should solve most
+problems with critical reads after writes.
+
+```
+[CCRFilter]
+type=filter
+module=ccrfilter
+time=5
+```
+
+This configuration will force all read queries after a write to the master for 5
+seconds, preventing read scaling until the modifications have been replicated to
+the slaves.
+
+For best performance, the value of _time_ should be slightly greater than the
+actual replication lag between the master and its slaves. If the number of
+critical read statements is known, the _count_ parameter could be used to
+control the number reads that are sent to the master.

Documentation/Filters/Cache.md

@@ -1,5 +1,7 @@
 # Cache
 
+This filter was introduced in MariaDB MaxScale 2.1.
+
 ## Overview
 The cache filter is a simple cache that is capable of caching the result of
 SELECTs, so that subsequent identical SELECTs are served directly by MaxScale,
@@ -8,6 +10,11 @@ without the queries being routed to any server.
 _Note that the cache is still experimental and that non-backward compatible
 changes may be made._
 
+Note that installing the cache causes all statements to be parsed. The
+implication of that is that unless statements _already_ need to be parsed,
+e.g. due to the presence of another filter or the chosen router, then adding
+the cache will not necessarily improve the performance, but may decrease it.
+
 ## Limitations
 
 All of these limitations may be addressed in forthcoming releases.
@@ -639,3 +646,44 @@ The value is a boolean and the default is `false`.
 ```
 storage_options=collect_statistics=true
 ```
+
+# Example
+
+In the following we define a cache _MyCache_ that uses the cache storage module
+`storage_inmemory` and whose _soft ttl_ is `30` seconds and whose _hard ttl_ is
+`45` seconds. The cached data is shared between all threads and the maximum size
+of the cached data is `50` mebibytes. The rules for the cache are in the file
+`cache_rules.json`.
+
+### Configuration
+```
+[MyCache]
+type=filter
+module=cache
+storage=storage_inmemory
+soft_ttl=30
+hard_ttl=45
+cached_data=shared
+max_size=50Mi
+rules=cache_rules.json
+
+[MyService]
+type=service
+...
+filters=MyCache
+```
+
+### `cache_rules.json`
+The rules specify that the data of the table `sbtest` should be cached.
+
+```
+{
+    "store": [
+        {
+            "attribute": "table",
+            "op": "=",
+            "value": "sbtest"
+        }
+    ]
+}
+```

Documentation/Filters/Insert-Stream-Filter.md

@@ -1,5 +1,8 @@
 # Insert Stream Filter
 
+This filter was introduced in MariaDB MaxScale 2.1.
+
+## Overview
 The _insertstream_ filter converts bulk inserts into CSV data streams that are
 consumed by the backend server via the LOAD DATA LOCAL INFILE mechanism. This
 leverages the speed advantage of LOAD DATA LOCAL INFILE over regular inserts

Documentation/Filters/Masking.md

@@ -1,5 +1,7 @@
 # Masking
 
+This filter was introduced in MariaDB MaxScale 2.1.
+
 ## Overview
 With the _masking_ filter it is possible to obfuscate the returned
 value of a particular column.
@@ -302,3 +304,47 @@ MaxScale> call command masking reload MyMaskingFilter
 ```
 `MyMaskingFilter` refers to a particular filter section in the
 MariaDB MaxScale configuration file.
+
+# Example
+
+In the following we configure a masking filter _MyMasking_ that should always log a
+warning if a masking rule matches a column that is of a type that cannot be masked,
+and that should abort the client connection if a resultset package is larger than
+16MB. The rules for the masking filter are in the file `masking_rules.json`.
+
+### Configuration
+```
+[MyMasking]
+type=filter
+module=masking
+warn_type_mismatch=always
+large_payload=abort
+rules=masking_rules.json
+
+[MyService]
+type=service
+...
+filters=MyMasking
+```
+
+### `masking_rules.json`
+
+The rules specify that the data of a column whose name is `ssn`, should
+be replaced with the string _012345-ABCD_. If the length of the data is
+not exactly the same as the length of the replacement value, then the
+data should be replaced with as many _X_ characters as needed.
+```
+{
+    "rules": [
+        {
+            "replace": {
+                "column": "ssn"
+            },
+            "with": {
+                "value": "012345-ABCD",
+                "fill": "X"
+            }
+        }
+    ]
+}
+```

Documentation/Filters/Maxrows.md

@@ -1,5 +1,7 @@
 # Maxrows
 
+This filter was introduced in MariaDB MaxScale 2.1.
+
 ## Overview
 The maxrows filter is capable of restricting the amount of rows that a SELECT,
  a prepared statement or stored procedure could return to the client application.
@@ -68,3 +70,16 @@ Default is `0`. To log everything, give `debug` a value of `3`.
 ```
 debug=2
 ```
+
+## Example Configuration
+
+Here is an example of filter configuration where the max number of returned
+rows is 10000 and max allowed resultset size is 256KB
+
+```
+[MaxRows]
+type=filter
+module=maxrows
+max_resultset_rows=10000
+max_resultset_size=256000
+```

Documentation/Release-Notes/MaxScale-2.1.0-Release-Notes.md

@@ -10,6 +10,38 @@ report at [Jira](https://jira.mariadb.org).
 
 ## Changed Features
 
+### `router_options` to Parameters
+
+The `router_options` values can also be given as parameters to the service for
+the _readwritesplit_, _schemarouter_ and _binlogrouter_ modules.
+
+What this means is that in MaxScale 2.1 the following _readwritesplit_
+configration.
+
+```
+[RW Split Router]
+type=service
+router=readwritesplit
+servers=server1
+user=maxuser
+passwd=maxpwd
+router_options=slave_selection_criteria=LEAST_ROUTER_CONNECTIONS,max_sescmd_history=10,disable_sescmd_history=false
+```
+
+Can also be written in the following form.
+
+```
+[RW Split Router]
+type=service
+router=readwritesplit
+servers=server1
+user=maxuser
+passwd=maxpwd
+slave_selection_criteria=LEAST_ROUTER_CONNECTIONS
+max_sescmd_history=10
+disable_sescmd_history=false
+```
+
 ### Configuration Files
 
 From 2.1.0 onwards MariaDB MaxScale supports hierarchical configuration
@@ -271,6 +303,17 @@ to large sets of data with a single query.
 For more information, refer to the [Maxrows](../Filters/Maxrows.md)
 documentation.
 
+### Insert stream filter
+
+The _insertstream_ filter converts bulk inserts into CSV data streams that are
+consumed by the backend server via the LOAD DATA LOCAL INFILE mechanism. This
+leverages the speed advantage of LOAD DATA LOCAL INFILE over regular inserts
+while also reducing the overall network traffic by condensing the inserted
+values into CSV.
+
+For more information, refer to the [Insert Stream Filter](../Filters/Insert-Stream-Filter.md)
+documentation.
+
 ### Galeramon Monitor new option
 The `set_donor_nodes` option allows the setting of _global variable_ _wsrep_sst_donor_  with a list the preferred donor nodes (among slave ones).
 

Documentation/Upgrading/Upgrading-To-MaxScale-2.1.md

@@ -0,0 +1,56 @@
+# Upgrading MariaDB MaxScale from 2.0 to 2.1
+
+This document describes particular issues to take into account when upgrading
+MariaDB MaxScale from version 2.0 to 2.1.
+
+For more information about MariaDB MaxScale 2.1, please refer to the
+[ChangeLog](../Changelog.md).
+
+For a complete list of changes in MaxScale 2.1.0, refer to the
+[MaxScale 2.1.0 Release Notes](../Release-Notes/MaxScale-2.1.0-Release-Notes.md).
+
+## Installation
+
+Before starting the upgrade, we **strongly** recommend you back up your current
+configuration file.
+
+## MaxScale Log Files
+
+The name of the log file was changed from _maxscaleN.log_ to _maxscale.log_. The
+default location for the log file is _/var/log/maxscale/maxscale.log_.
+
+Rotating the log files will cause MaxScale to reopen the file instead of
+renaming them. This makes the MaxScale logging facility _logrotate_ compatible.
+
+## ReadWriteSplit
+
+The `disable_sescmd_history` option is now enabled by default. This means that
+slaves will not be recovered mid-session even if a replacement slave is
+available. To enable the legacy behavior, add the `disable_sescmd_history=true`
+parameter to the service definition.
+
+## Persistent Connections
+
+The MySQL session state is reset in MaxScale 2.1 for persistent
+connections. This means that any modifications to the session state (default
+database, user variable etc.) will not survive if the connection is put into the
+connection pool. For most users, this is the expected behavior.
+
+## User Data Cache
+
+The location of the MySQL user data cache was moved from
+`/var/cache/maxscale/<Service>` to `/var/cache/maxscale/<Service>/<Listener>`.
+
+## Galeramon Monitoring Algorithm
+
+Galeramon will assign the master status *only* to the node which has a
+_wsrep_local_index_ value of 0. This will guarantee consistent writes with
+multiple MaxScales but it also causes slower changes of the master node.
+
+To enable the legacy behavior, add `root_node_as_master=false` to the Galera
+monitor configuration.
+
+## MaxAdmin Editing Mode
+
+The default editing mode was changed from _vim_ to _emacs_ mode. To start
+maxadmin in the legacy mode, use the `-i` option.

include/maxscale/dcb.h

@@ -190,7 +190,6 @@ typedef struct dcb
     bool            draining_flag;  /**< Set while write queue is drained */
     bool            drain_called_while_busy; /**< Set as described */
     dcb_role_t      dcb_role;
-    SPINLOCK        dcb_initlock;
     DCBEVENTQ       evq;            /**< The event queue for this DCB */
     int             fd;             /**< The descriptor */
     dcb_state_t     state;          /**< Current descriptor state */
@@ -207,32 +206,20 @@ typedef struct dcb
     struct servlistener *listener;  /**< For a client DCB, the listener data */
     MXS_PROTOCOL    func;           /**< The protocol functions for this descriptor */
     MXS_AUTHENTICATOR authfunc;     /**< The authenticator functions for this descriptor */
-
     int             writeqlen;      /**< Current number of byes in the write queue */
-    SPINLOCK        writeqlock;     /**< Write Queue spinlock */
     GWBUF           *writeq;        /**< Write Data Queue */
-    SPINLOCK        delayqlock;     /**< Delay Backend Write Queue spinlock */
     GWBUF           *delayq;        /**< Delay Backend Write Data Queue */
     GWBUF           *dcb_readqueue; /**< read queue for storing incomplete reads */
     GWBUF           *dcb_fakequeue; /**< Fake event queue for generated events */
 
     DCBSTATS        stats;          /**< DCB related statistics */
-    unsigned int    dcb_server_status; /*< the server role indicator from SERVER */
     struct dcb      *nextpersistent;   /**< Next DCB in the persistent pool for SERVER */
     time_t          persistentstart;   /**< Time when DCB placed in persistent pool */
     struct service  *service;       /**< The related service */
     void            *data;          /**< Specific client data, shared between DCBs of this session */
     void            *authenticator_data; /**< The authenticator data for this DCB */
     DCBMM           memdata;        /**< The data related to DCB memory management */
-    SPINLOCK        cb_lock;        /**< The lock for the callbacks linked list */
     DCB_CALLBACK    *callbacks;     /**< The list of callbacks for the DCB */
-    SPINLOCK        pollinlock;
-    int             pollinbusy;
-    int             readcheck;
-
-    SPINLOCK        polloutlock;
-    int             polloutbusy;
-    int             writecheck;
     long            last_read;      /*< Last time the DCB received data */
     int             high_water;     /**< High water mark */
     int             low_water;      /**< Low water mark */
@@ -242,7 +229,6 @@ typedef struct dcb
     bool            ssl_read_want_write;    /*< Flag */
     bool            ssl_write_want_read;    /*< Flag */
     bool            ssl_write_want_write;    /*< Flag */
-    int             dcb_port;       /**< port of target server */
     bool            was_persistent;  /**< Whether this DCB was in the persistent pool */
     struct
     {
@@ -253,13 +239,11 @@ typedef struct dcb
     skygw_chk_t     dcb_chk_tail;
 } DCB;
 
-#define DCB_INIT {.dcb_chk_top = CHK_NUM_DCB, .dcb_initlock = SPINLOCK_INIT, \
+#define DCB_INIT {.dcb_chk_top = CHK_NUM_DCB, \
     .evq = DCBEVENTQ_INIT, .ipv4 = {0}, .func = {0}, .authfunc = {0}, \
-    .writeqlock = SPINLOCK_INIT, .delayqlock = SPINLOCK_INIT, \
     .stats = {0}, .memdata = DCBMM_INIT, \
-    .cb_lock = SPINLOCK_INIT, .pollinlock = SPINLOCK_INIT, \
     .fd = DCBFD_CLOSED, .stats = DCBSTATS_INIT, .ssl_state = SSL_HANDSHAKE_UNKNOWN, \
-    .state = DCB_STATE_ALLOC, .polloutlock = SPINLOCK_INIT, .dcb_chk_tail = CHK_NUM_DCB, \
+    .state = DCB_STATE_ALLOC, .dcb_chk_tail = CHK_NUM_DCB, \
     .authenticator_data = NULL, .thread = {0}}
 
 /**

include/maxscale/protocol/mysql.h

@@ -269,7 +269,6 @@ typedef struct
 #endif
     int                    fd;                           /*< The socket descriptor */
     struct dcb*            owner_dcb;                    /*< The DCB of the socket we are running on */
-    SPINLOCK               protocol_lock;                /*< Protocol lock */
     mysql_server_cmd_t     current_command;              /*< Current command being executed */
     server_command_t       protocol_command;             /*< session command list */
     server_command_t*      protocol_cmd_history;         /*< session command history */

include/maxscale/session.h

@@ -126,7 +126,6 @@ typedef struct mxs_upstream
 typedef struct session
 {
     skygw_chk_t             ses_chk_top;
-    SPINLOCK                ses_lock;
     mxs_session_state_t     state;            /*< Current descriptor state */
     size_t                  ses_id;           /*< Unique session identifier */
     int                     enabled_log_priorities; /*< Bitfield of enabled syslog priorities */

server/core/config.c

@@ -1931,8 +1931,9 @@ check_config_objects(CONFIG_CONTEXT *context)
                     if (mod == NULL ||
                         !config_param_is_valid(mod->parameters, params->name, params->value, context))
                     {
-                        MXS_ERROR("Unexpected parameter '%s' or parameter value for object '%s' of type '%s'.",
+                        MXS_ERROR("Unexpected parameter '%s' for object '%s' of type '%s', "
-                                  params->name, obj->object, type);
+                                  "or '%s' is an invalid value for parameter '%s'.",
+                                  params->name, obj->object, type, params->value, params->name);
                         rval = false;
                     }
                     else if (is_path_parameter(mod->parameters, params->name))

server/core/dcb.c

@@ -429,13 +429,13 @@ dcb_free_all_memory(DCB *dcb)
         gwbuf_free(dcb->dcb_fakequeue);
         dcb->dcb_fakequeue = NULL;
     }
-    spinlock_acquire(&dcb->cb_lock);
+
     while ((cb_dcb = dcb->callbacks) != NULL)
     {
         dcb->callbacks = cb_dcb->next;
         MXS_FREE(cb_dcb);
     }
-    spinlock_release(&dcb->cb_lock);
+
     if (dcb->ssl)
     {
         SSL_free(dcb->ssl);
@@ -757,10 +757,6 @@ dcb_connect(SERVER *server, MXS_SESSION *session, const char *protocol)
      */
     dcb->server = server;
 
-    /** Copy status field to DCB */
-    dcb->dcb_server_status = server->status;
-    dcb->dcb_port = server->port;
-
     dcb->was_persistent = false;
 
     /**
@@ -1721,13 +1717,13 @@ dcb_maybe_add_persistent(DCB *dcb)
                 session_put_ref(local_session);
             }
         }
-        spinlock_acquire(&dcb->cb_lock);
+
         while ((loopcallback = dcb->callbacks) != NULL)
         {
             dcb->callbacks = loopcallback->next;
             MXS_FREE(loopcallback);
         }
-        spinlock_release(&dcb->cb_lock);
+
         dcb->nextpersistent = dcb->server->persistent[dcb->thread.id];
         dcb->server->persistent[dcb->thread.id] = dcb;
         atomic_add(&dcb->server->stats.n_persistent, 1);
@@ -2070,20 +2066,7 @@ dprintDCB(DCB *pdcb, DCB *dcb)
     {
         dcb_printf(pdcb, "\t\tDCB is a clone.\n");
     }
-#if SPINLOCK_PROFILE
+
-    dcb_printf(pdcb, "\tInitlock Statistics:\n");
-    spinlock_stats(&dcb->dcb_initlock, spin_reporter, pdcb);
-    dcb_printf(pdcb, "\tWrite Queue Lock Statistics:\n");
-    spinlock_stats(&dcb->writeqlock, spin_reporter, pdcb);
-    dcb_printf(pdcb, "\tDelay Queue Lock Statistics:\n");
-    spinlock_stats(&dcb->delayqlock, spin_reporter, pdcb);
-    dcb_printf(pdcb, "\tPollin Lock Statistics:\n");
-    spinlock_stats(&dcb->pollinlock, spin_reporter, pdcb);
-    dcb_printf(pdcb, "\tPollout Lock Statistics:\n");
-    spinlock_stats(&dcb->polloutlock, spin_reporter, pdcb);
-    dcb_printf(pdcb, "\tCallback Lock Statistics:\n");
-    spinlock_stats(&dcb->cb_lock, spin_reporter, pdcb);
-#endif
     if (dcb->persistentstart)
     {
         char buff[20];
@@ -2337,8 +2320,8 @@ dcb_add_callback(DCB *dcb,
     ptr->cb = callback;
     ptr->userdata = userdata;
     ptr->next = NULL;
-    spinlock_acquire(&dcb->cb_lock);
     cb = dcb->callbacks;
+
     while (cb)
     {
         if (cb->reason == reason && cb->cb == callback &&
@@ -2346,7 +2329,6 @@ dcb_add_callback(DCB *dcb,
         {
             /* Callback is a duplicate, abandon it */
             MXS_FREE(ptr);
-            spinlock_release(&dcb->cb_lock);
             return 0;
         }
         lastcb = cb;
@@ -2360,7 +2342,7 @@ dcb_add_callback(DCB *dcb,
     {
         lastcb->next = ptr;
     }
-    spinlock_release(&dcb->cb_lock);
+
     return 1;
 }
 
@@ -2384,9 +2366,8 @@ dcb_remove_callback(DCB *dcb,
 {
     DCB_CALLBACK *cb, *pcb = NULL;
     int          rval = 0;
-
-    spinlock_acquire(&dcb->cb_lock);
     cb = dcb->callbacks;
+
     if (cb == NULL)
     {
         rval = 0;
@@ -2407,7 +2388,7 @@ dcb_remove_callback(DCB *dcb,
                 {
                     dcb->callbacks = cb->next;
                 }
-                spinlock_release(&dcb->cb_lock);
+
                 MXS_FREE(cb);
                 rval = 1;
                 break;
@@ -2416,10 +2397,7 @@ dcb_remove_callback(DCB *dcb,
             cb = cb->next;
         }
     }
-    if (!rval)
+
-    {
-        spinlock_release(&dcb->cb_lock);
-    }
     return rval;
 }
 
@@ -2433,22 +2411,19 @@ static void
 dcb_call_callback(DCB *dcb, DCB_REASON reason)
 {
     DCB_CALLBACK *cb, *nextcb;
-
-    spinlock_acquire(&dcb->cb_lock);
     cb = dcb->callbacks;
+
     while (cb)
     {
         if (cb->reason == reason)
         {
             nextcb = cb->next;
-            spinlock_release(&dcb->cb_lock);
 
             MXS_DEBUG("%lu [dcb_call_callback] %s",
                       pthread_self(),
                       STRDCBREASON(reason));
 
             cb->cb(dcb, reason, cb->userdata);
-            spinlock_acquire(&dcb->cb_lock);
             cb = nextcb;
         }
         else
@@ -2456,7 +2431,6 @@ dcb_call_callback(DCB *dcb, DCB_REASON reason)
             cb = cb->next;
         }
     }
-    spinlock_release(&dcb->cb_lock);
 }
 
 /**
@@ -2488,13 +2462,11 @@ dcb_hangup_foreach(struct server* server)
 
         for (DCB *dcb = all_dcbs[i]; dcb; dcb = dcb->thread.next)
         {
-            spinlock_acquire(&dcb->dcb_initlock);
             if (dcb->state == DCB_STATE_POLLING && dcb->server &&
                 dcb->server == server)
             {
                 poll_fake_hangup_event(dcb);
             }
-            spinlock_release(&dcb->dcb_initlock);
         }
 
         spinlock_release(&all_dcbs_lock[i]);

server/core/maxscale/session.h

@@ -25,7 +25,7 @@ MXS_BEGIN_DECLS
 #define MXS_UPSTREAM_INIT {0}
 #define SESSION_FILTER_INIT {0}
 
-#define SESSION_INIT {.ses_chk_top = CHK_NUM_SESSION, .ses_lock = SPINLOCK_INIT, \
+#define SESSION_INIT {.ses_chk_top = CHK_NUM_SESSION, \
     .stats = SESSION_STATS_INIT, .head = MXS_DOWNSTREAM_INIT, .tail = MXS_UPSTREAM_INIT, \
     .state = SESSION_STATE_ALLOC, .ses_chk_tail = CHK_NUM_SESSION}
 

server/core/poll.c

@@ -337,7 +337,6 @@ int poll_add_dcb(DCB *dcb)
     /*<
      * Choose new state according to the role of dcb.
      */
-    spinlock_acquire(&dcb->dcb_initlock);
     if (dcb->dcb_role == DCB_ROLE_CLIENT_HANDLER || dcb->dcb_role == DCB_ROLE_BACKEND_HANDLER)
     {
         new_state = DCB_STATE_POLLING;
@@ -388,7 +387,6 @@ int poll_add_dcb(DCB *dcb)
     }
 
     dcb->thread.id = owner;
-    spinlock_release(&dcb->dcb_initlock);
 
     dcb_add_to_list(dcb);
 
@@ -396,7 +394,6 @@ int poll_add_dcb(DCB *dcb)
 
     if (dcb->dcb_role == DCB_ROLE_SERVICE_LISTENER)
     {
-        spinlock_acquire(&dcb->dcb_initlock);
         /** Listeners are added to all epoll instances */
         int nthr = config_threadcount();
 
@@ -413,7 +410,6 @@ int poll_add_dcb(DCB *dcb)
                 break;
             }
         }
-        spinlock_release(&dcb->dcb_initlock);
     }
     else
     {
@@ -448,12 +444,10 @@ int poll_remove_dcb(DCB *dcb)
     struct  epoll_event ev;
     CHK_DCB(dcb);
 
-    spinlock_acquire(&dcb->dcb_initlock);
     /*< It is possible that dcb has already been removed from the set */
     if (dcb->state == DCB_STATE_NOPOLLING ||
         dcb->state == DCB_STATE_ZOMBIE)
     {
-        spinlock_release(&dcb->dcb_initlock);
         return 0;
     }
     if (DCB_STATE_POLLING != dcb->state
@@ -478,7 +472,6 @@ int poll_remove_dcb(DCB *dcb)
      * DCB_STATE_NOPOLLING.
      */
     dcbfd = dcb->fd;
-    spinlock_release(&dcb->dcb_initlock);
 
     if (dcbfd > 0)
     {
@@ -486,7 +479,6 @@ int poll_remove_dcb(DCB *dcb)
 
         if (dcb->dcb_role == DCB_ROLE_SERVICE_LISTENER)
         {
-            spinlock_acquire(&dcb->dcb_initlock);
             /** Listeners are added to all epoll instances */
             int nthr = config_threadcount();
 
@@ -502,7 +494,6 @@ int poll_remove_dcb(DCB *dcb)
                     ss_dassert(error_num);
                 }
             }
-            spinlock_release(&dcb->dcb_initlock);
         }
         else
         {
@@ -925,15 +916,12 @@ process_pollq(int thread_id, struct epoll_event *event)
         thread_data[thread_id].event = ev;
     }
 
-    ss_debug(spinlock_acquire(&dcb->dcb_initlock));
-    ss_dassert(dcb->state != DCB_STATE_ALLOC);
     /* It isn't obvious that this is impossible */
     /* ss_dassert(dcb->state != DCB_STATE_DISCONNECTED); */
     if (DCB_STATE_DISCONNECTED == dcb->state)
     {
         return 0;
     }
-    ss_debug(spinlock_release(&dcb->dcb_initlock));
 
     MXS_DEBUG("%lu [poll_waitevents] event %d dcb %p "
               "role %s",
@@ -1059,11 +1047,10 @@ process_pollq(int thread_id, struct epoll_event *event)
                   eno,
                   strerror_r(eno, errbuf, sizeof(errbuf)));
         ts_stats_increment(pollStats.n_hup, thread_id);
-        spinlock_acquire(&dcb->dcb_initlock);
         if ((dcb->flags & DCBF_HUNG) == 0)
         {
             dcb->flags |= DCBF_HUNG;
-            spinlock_release(&dcb->dcb_initlock);
+
             /** Read session id to thread's local storage */
             dcb_get_ses_log_info(dcb,
                                  &mxs_log_tls.li_sesid,
@@ -1074,10 +1061,6 @@ process_pollq(int thread_id, struct epoll_event *event)
                 dcb->func.hangup(dcb);
             }
         }
-        else
-        {
-            spinlock_release(&dcb->dcb_initlock);
-        }
     }
 
 #ifdef EPOLLRDHUP
@@ -1094,11 +1077,11 @@ process_pollq(int thread_id, struct epoll_event *event)
                   eno,
                   strerror_r(eno, errbuf, sizeof(errbuf)));
         ts_stats_increment(pollStats.n_hup, thread_id);
-        spinlock_acquire(&dcb->dcb_initlock);
+
         if ((dcb->flags & DCBF_HUNG) == 0)
         {
             dcb->flags |= DCBF_HUNG;
-            spinlock_release(&dcb->dcb_initlock);
+
             /** Read session id to thread's local storage */
             dcb_get_ses_log_info(dcb,
                                  &mxs_log_tls.li_sesid,
@@ -1109,10 +1092,6 @@ process_pollq(int thread_id, struct epoll_event *event)
                 dcb->func.hangup(dcb);
             }
         }
-        else
-        {
-            spinlock_release(&dcb->dcb_initlock);
-        }
     }
 #endif
 

server/core/random_jkiss.c

@@ -31,7 +31,6 @@
 #include <sys/stat.h>
 #include <fcntl.h>
 #include <unistd.h>
-#include <maxscale/spinlock.h>
 #include <maxscale/random_jkiss.h>
 
 /* Public domain code for JKISS RNG - Comment header added */
@@ -42,8 +41,6 @@
 static unsigned int x = 123456789, y = 987654321, z = 43219876, c = 6543217; /* Seed variables */
 static bool init = false;
 
-static SPINLOCK random_jkiss_spinlock = SPINLOCK_INIT;
-
 static unsigned int random_jkiss_devrand(void);
 static void random_init_jkiss(void);
 
@@ -60,14 +57,11 @@ random_jkiss(void)
     unsigned long long t;
     unsigned int result;
 
-    spinlock_acquire(&random_jkiss_spinlock);
     if (!init)
     {
         /* Must set init first because initialisation calls this function */
         init = true;
-        spinlock_release(&random_jkiss_spinlock);
         random_init_jkiss();
-        spinlock_acquire(&random_jkiss_spinlock);
     }
     x = 314527869 * x + 1234567;
     y ^= y << 5;
@@ -77,7 +71,6 @@ random_jkiss(void)
     c = t >> 32;
     z = t;
     result = x + y + z;
-    spinlock_release(&random_jkiss_spinlock);
     return result;
 }
 
@@ -120,7 +113,6 @@ random_init_jkiss(void)
 {
     int newrand, i;
 
-    spinlock_acquire(&random_jkiss_spinlock);
     if ((newrand = random_jkiss_devrand()) != 0)
     {
         x = newrand;
@@ -140,7 +132,6 @@ random_init_jkiss(void)
     {
         c = newrand % 698769068 + 1; /* Should be less than 698769069 */
     }
-    spinlock_release(&random_jkiss_spinlock);
 
     /* "Warm up" our random number generator */
     for (i = 0; i < 100; i++)

server/core/session.c

@@ -230,7 +230,6 @@ session_set_dummy(DCB *client_dcb)
     session->ses_chk_top = CHK_NUM_SESSION;
     session->ses_chk_tail = CHK_NUM_SESSION;
     session->ses_is_child = false;
-    spinlock_init(&session->ses_lock);
     session->service = NULL;
     session->client_dcb = NULL;
     session->n_filters = 0;
@@ -285,20 +284,17 @@ void session_disable_log_priority(MXS_SESSION* session, int priority)
 bool
 session_link_dcb(MXS_SESSION *session, DCB *dcb)
 {
-    spinlock_acquire(&session->ses_lock);
     ss_info_dassert(session->state != SESSION_STATE_FREE,
                     "If session->state is SESSION_STATE_FREE then this attempt to "
                     "access freed memory block.");
     if (session->state == SESSION_STATE_FREE)
     {
-        spinlock_release(&session->ses_lock);
         return false;
     }
     atomic_add(&session->refcount, 1);
     dcb->session = session;
     /** Move this DCB under the same thread */
     dcb->thread.id = session->client_dcb->thread.id;
-    spinlock_release(&session->ses_lock);
     return true;
 }
 

server/modules/filter/CMakeLists.txt

@@ -6,6 +6,7 @@ add_subdirectory(hintfilter)
 add_subdirectory(luafilter)
 add_subdirectory(mqfilter)
 add_subdirectory(namedserverfilter)
+add_subdirectory(nullfilter)
 add_subdirectory(qlafilter)
 add_subdirectory(regexfilter)
 add_subdirectory(tee)

server/modules/filter/nullfilter/CMakeLists.txt

@@ -0,0 +1,7 @@
+add_library(nullfilter SHARED
+  nullfilter.cc
+  nullfiltersession.cc
+  )
+target_link_libraries(nullfilter maxscale-common)
+set_target_properties(nullfilter PROPERTIES VERSION "1.0.0")
+install_module(nullfilter core)

server/modules/filter/nullfilter/nullfilter.cc

@@ -0,0 +1,133 @@
+/*
+ * Copyright (c) 2016 MariaDB Corporation Ab
+ *
+ * Use of this software is governed by the Business Source License included
+ * in the LICENSE.TXT file and at www.mariadb.com/bsl.
+ *
+ * Change Date: 2019-07-01
+ *
+ * On the date above, in accordance with the Business Source License, use
+ * of this software will be governed by version 2 or later of the General
+ * Public License.
+ */
+
+#define MXS_MODULE_NAME "nullfilter"
+#include "nullfilter.hh"
+#include <string>
+#include <maxscale/utils.h>
+
+using std::string;
+
+namespace
+{
+
+#define VERSION_STRING "V1.0.0"
+
+const char CAPABILITIES_PARAM[] = "capabilities";
+
+MXS_ENUM_VALUE capability_values[] =
+{
+    { "RCAP_TYPE_STMT_INPUT",           RCAP_TYPE_STMT_INPUT },
+    { "RCAP_TYPE_CONTIGUOUS_INPUT",     RCAP_TYPE_CONTIGUOUS_INPUT },
+    { "RCAP_TYPE_TRANSACTION_TRACKING", RCAP_TYPE_TRANSACTION_TRACKING },
+    { "RCAP_TYPE_STMT_OUTPUT",          RCAP_TYPE_STMT_OUTPUT },
+    { "RCAP_TYPE_CONTIGUOUS_OUTPUT",    RCAP_TYPE_CONTIGUOUS_OUTPUT },
+    { "RCAP_TYPE_RESULTSET_OUTPUT",     RCAP_TYPE_RESULTSET_OUTPUT },
+    { NULL, 0 }
+};
+
+struct unit_variables
+{
+    uint64_t capabilities;
+    bool     capabilities_set;
+} this_unit =
+{
+    0,
+    false
+};
+
+}
+
+//
+// Global symbols of the Module
+//
+
+extern "C" MXS_MODULE* MXS_CREATE_MODULE()
+{
+    MXS_NOTICE("Nullfilter module %s initialized.", VERSION_STRING);
+
+    static MXS_MODULE info =
+    {
+        MXS_MODULE_API_FILTER,
+        MXS_MODULE_IN_DEVELOPMENT,
+        MXS_FILTER_VERSION,
+        "A null filter that does nothing.",
+        VERSION_STRING,
+        &NullFilter::s_object,
+        NULL, /* Process init. */
+        NULL, /* Process finish. */
+        NULL, /* Thread init. */
+        NULL, /* Thread finish. */
+        {
+            { CAPABILITIES_PARAM, MXS_MODULE_PARAM_ENUM, NULL, MXS_MODULE_OPT_REQUIRED, capability_values },
+            { MXS_END_MODULE_PARAMS }
+        }
+    };
+
+    return &info;
+}
+
+//
+// NullFilter
+//
+
+NullFilter::NullFilter(const char* zName)
+{
+    MXS_NOTICE("Null filter [%s] created.", zName);
+}
+
+NullFilter::~NullFilter()
+{
+}
+
+// static
+NullFilter* NullFilter::create(const char* zName, char**, MXS_CONFIG_PARAMETER* pParams)
+{
+    NullFilter* pFilter = NULL;
+
+    uint64_t capabilities = config_get_enum(pParams, CAPABILITIES_PARAM, capability_values);
+
+    if (this_unit.capabilities_set)
+    {
+        MXS_WARNING("The capabilities reported by NullFilter are currently global, "
+                    "and not specific for a particular NullFilter instance.");
+    }
+
+    this_unit.capabilities = capabilities;
+    this_unit.capabilities_set = true;
+
+    return new NullFilter(zName);
+}
+
+
+NullFilterSession* NullFilter::newSession(MXS_SESSION* pSession)
+{
+    return NullFilterSession::create(pSession, this);
+}
+
+// static
+void NullFilter::diagnostics(DCB* pDcb)
+{
+    dcb_printf(pDcb, "Hello, World!\n");
+}
+
+// static
+uint64_t NullFilter::getCapabilities()
+{
+    if (!this_unit.capabilities_set)
+    {
+        MXS_ERROR("getCapabilities() called before they have been set.");
+    }
+
+    return this_unit.capabilities;
+}

server/modules/filter/nullfilter/nullfilter.hh

@@ -0,0 +1,36 @@
+#pragma once
+/*
+ * Copyright (c) 2016 MariaDB Corporation Ab
+ *
+ * Use of this software is governed by the Business Source License included
+ * in the LICENSE.TXT file and at www.mariadb.com/bsl.
+ *
+ * Change Date: 2019-07-01
+ *
+ * On the date above, in accordance with the Business Source License, use
+ * of this software will be governed by version 2 or later of the General
+ * Public License.
+ */
+
+#include <maxscale/cppdefs.hh>
+#include <maxscale/filter.hh>
+#include "nullfiltersession.hh"
+
+class NullFilter : public maxscale::Filter<NullFilter, NullFilterSession>
+{
+public:
+    ~NullFilter();
+    static NullFilter* create(const char* zName, char** pzOptions, MXS_CONFIG_PARAMETER* pParams);
+
+    NullFilterSession* newSession(MXS_SESSION* pSession);
+
+    void diagnostics(DCB* pDcb);
+
+    static uint64_t getCapabilities();
+
+private:
+    NullFilter(const char* zName);
+
+    NullFilter(const NullFilter&);
+    NullFilter& operator = (const NullFilter&);
+};

server/modules/filter/nullfilter/nullfiltersession.cc

@@ -0,0 +1,31 @@
+/*
+ * Copyright (c) 2016 MariaDB Corporation Ab
+ *
+ * Use of this software is governed by the Business Source License included
+ * in the LICENSE.TXT file and at www.mariadb.com/bsl.
+ *
+ * Change Date: 2019-07-01
+ *
+ * On the date above, in accordance with the Business Source License, use
+ * of this software will be governed by version 2 or later of the General
+ * Public License.
+ */
+
+#define MXS_MODULE_NAME "nullfilter"
+#include "nullfiltersession.hh"
+
+NullFilterSession::NullFilterSession(MXS_SESSION* pSession, const NullFilter* pFilter)
+    : maxscale::FilterSession(pSession)
+    , m_filter(*pFilter)
+{
+}
+
+NullFilterSession::~NullFilterSession()
+{
+}
+
+//static
+NullFilterSession* NullFilterSession::create(MXS_SESSION* pSession, const NullFilter* pFilter)
+{
+    return new NullFilterSession(pSession, pFilter);
+}

server/modules/filter/nullfilter/nullfiltersession.hh

@@ -0,0 +1,35 @@
+#pragma once
+/*
+ * Copyright (c) 2016 MariaDB Corporation Ab
+ *
+ * Use of this software is governed by the Business Source License included
+ * in the LICENSE.TXT file and at www.mariadb.com/bsl.
+ *
+ * Change Date: 2019-07-01
+ *
+ * On the date above, in accordance with the Business Source License, use
+ * of this software will be governed by version 2 or later of the General
+ * Public License.
+ */
+
+#include <maxscale/cppdefs.hh>
+#include <maxscale/filter.hh>
+
+class NullFilter;
+
+class NullFilterSession : public maxscale::FilterSession
+{
+public:
+    ~NullFilterSession();
+
+    static NullFilterSession* create(MXS_SESSION* pSession, const NullFilter* pFilter);
+
+private:
+    NullFilterSession(MXS_SESSION* pSession, const NullFilter* pFilter);
+
+    NullFilterSession(const NullFilterSession&);
+    NullFilterSession& operator = (const NullFilterSession&);
+
+private:
+    const NullFilter& m_filter;
+};

server/modules/filter/tee/tee.c

@@ -536,7 +536,6 @@ closeSession(MXS_FILTER *instance, MXS_FILTER_SESSION *session)
         if ((bsession = my_session->branch_session) != NULL)
         {
             CHK_SESSION(bsession);
-            spinlock_acquire(&bsession->ses_lock);
 
             if (bsession->state != SESSION_STATE_STOPPING)
             {
@@ -545,7 +544,6 @@ closeSession(MXS_FILTER *instance, MXS_FILTER_SESSION *session)
             router = bsession->service->router;
             router_instance = bsession->service->router_instance;
             rsession = bsession->router_session;
-            spinlock_release(&bsession->ses_lock);
 
             /** Close router session and all its connections */
             router->closeSession(router_instance, rsession);

server/modules/protocol/MySQL/MySQLBackend/mysql_backend.c

@@ -637,9 +637,7 @@ gw_reply_on_error(DCB *dcb, mxs_auth_state_t state)
                                               session->router_session,
                                               errbuf, dcb, ERRACT_REPLY_CLIENT, &succp);
 
-        spinlock_acquire(&session->ses_lock);
         session->state = SESSION_STATE_STOPPING;
-        spinlock_release(&session->ses_lock);
         ss_dassert(dcb->dcb_errhandle_called);
     }
     else
@@ -736,9 +734,7 @@ gw_read_and_write(DCB *dcb)
 
         if (!succp)
         {
-            spinlock_acquire(&session->ses_lock);
             session->state = SESSION_STATE_STOPPING;
-            spinlock_release(&session->ses_lock);
         }
         return 0;
     }
@@ -1173,22 +1169,7 @@ static int gw_error_backend_event(DCB *dcb)
                                        0,
                                        "Lost connection to backend server.");
 
-    spinlock_acquire(&session->ses_lock);
     ses_state = session->state;
-    spinlock_release(&session->ses_lock);
-
-    /**
-     * Session might be initialized when DCB already is in the poll set.
-     * Thus hangup can occur in the middle of session initialization.
-     * Only complete and successfully initialized sessions allow for
-     * calling error handler.
-     */
-    while (ses_state == SESSION_STATE_READY)
-    {
-        spinlock_acquire(&session->ses_lock);
-        ses_state = session->state;
-        spinlock_release(&session->ses_lock);
-    }
 
     if (ses_state != SESSION_STATE_ROUTER_READY)
     {
@@ -1225,9 +1206,7 @@ static int gw_error_backend_event(DCB *dcb)
      */
     if (!succp)
     {
-        spinlock_acquire(&session->ses_lock);
         session->state = SESSION_STATE_STOPPING;
-        spinlock_release(&session->ses_lock);
     }
 
 retblock:
@@ -1277,22 +1256,7 @@ static int gw_backend_hangup(DCB *dcb)
                                        0,
                                        "Lost connection to backend server.");
 
-    spinlock_acquire(&session->ses_lock);
     ses_state = session->state;
-    spinlock_release(&session->ses_lock);
-
-    /**
-     * Session might be initialized when DCB already is in the poll set.
-     * Thus hangup can occur in the middle of session initialization.
-     * Only complete and successfully initialized sessions allow for
-     * calling error handler.
-     */
-    while (ses_state == SESSION_STATE_READY)
-    {
-        spinlock_acquire(&session->ses_lock);
-        ses_state = session->state;
-        spinlock_release(&session->ses_lock);
-    }
 
     if (ses_state != SESSION_STATE_ROUTER_READY)
     {
@@ -1330,9 +1294,7 @@ static int gw_backend_hangup(DCB *dcb)
     /** There are no required backends available, close session. */
     if (!succp)
     {
-        spinlock_acquire(&session->ses_lock);
         session->state = SESSION_STATE_STOPPING;
-        spinlock_release(&session->ses_lock);
     }
 
 retblock:
@@ -1371,7 +1333,7 @@ static int gw_backend_close(DCB *dcb)
          * but client's close and adding client's DCB to zombies list is executed
          * only if client's DCB's state does _not_ change in parallel.
          */
-        spinlock_acquire(&session->ses_lock);
+
         /**
          * If session->state is STOPPING, start closing client session.
          * Otherwise only this backend connection is closed.
@@ -1381,19 +1343,9 @@ static int gw_backend_close(DCB *dcb)
         {
             if (session->client_dcb->state == DCB_STATE_POLLING)
             {
-                spinlock_release(&session->ses_lock);
-
                 /** Close client DCB */
                 dcb_close(session->client_dcb);
             }
-            else
-            {
-                spinlock_release(&session->ses_lock);
-            }
-        }
-        else
-        {
-            spinlock_release(&session->ses_lock);
         }
     }
     return 1;
@@ -1471,9 +1423,7 @@ static int backend_write_delayqueue(DCB *dcb, GWBUF *buffer)
 
         if (!succp)
         {
-            spinlock_acquire(&session->ses_lock);
             session->state = SESSION_STATE_STOPPING;
-            spinlock_release(&session->ses_lock);
         }
     }
 
@@ -1564,8 +1514,6 @@ static int gw_change_user(DCB *backend,
         memcpy(&backend_protocol->charset, client_auth_packet, sizeof(int));
     }
 
-    spinlock_acquire(&in_session->ses_lock);
-
     /* save current_database name */
     strcpy(current_database, current_session->db);
 
@@ -1595,7 +1543,6 @@ static int gw_change_user(DCB *backend,
                                             client_sha1, sizeof(client_sha1));
 
     strcpy(current_session->db, current_database);
-    spinlock_release(&in_session->ses_lock);
 
     if (auth_ret != 0)
     {
@@ -1603,7 +1550,6 @@ static int gw_change_user(DCB *backend,
         {
             /* Try authentication again with new repository data */
             /* Note: if no auth client authentication will fail */
-            spinlock_acquire(&in_session->ses_lock);
             *current_session->db = 0;
 
             auth_ret = dcb->authfunc.reauthenticate(dcb, username,
@@ -1613,7 +1559,6 @@ static int gw_change_user(DCB *backend,
                                                     client_sha1, sizeof(client_sha1));
 
             strcpy(current_session->db, current_database);
-            spinlock_release(&in_session->ses_lock);
         }
     }
 

server/modules/protocol/MySQL/MySQLClient/mysql_client.c

@@ -1361,7 +1361,6 @@ gw_client_close(DCB *dcb)
     if (session != NULL && SESSION_STATE_DUMMY != session->state)
     {
         CHK_SESSION(session);
-        spinlock_acquire(&session->ses_lock);
 
         if (session->state != SESSION_STATE_STOPPING)
         {
@@ -1375,14 +1374,9 @@ gw_client_close(DCB *dcb)
          */
         if (session->router_session != NULL)
         {
-            spinlock_release(&session->ses_lock);
             /** Close router session and all its connections */
             router->closeSession(router_instance, session->router_session);
         }
-        else
-        {
-            spinlock_release(&session->ses_lock);
-        }
     }
     return 1;
 }

server/modules/protocol/MySQL/mysql_common.c

@@ -132,27 +132,21 @@ void mysql_protocol_done(DCB* dcb)
 
     p = (MySQLProtocol *)dcb->protocol;
 
-    spinlock_acquire(&p->protocol_lock);
+    if (p->protocol_state == MYSQL_PROTOCOL_ACTIVE)
-
-    if (p->protocol_state != MYSQL_PROTOCOL_ACTIVE)
     {
-        goto retblock;
+        scmd = p->protocol_cmd_history;
+
+        while (scmd != NULL)
+        {
+            scmd2 = scmd->scom_next;
+            MXS_FREE(scmd);
+            scmd = scmd2;
+        }
+
+        gwbuf_free(p->stored_query);
+
+        p->protocol_state = MYSQL_PROTOCOL_DONE;
     }
-    scmd = p->protocol_cmd_history;
-
-    while (scmd != NULL)
-    {
-        scmd2 = scmd->scom_next;
-        MXS_FREE(scmd);
-        scmd = scmd2;
-    }
-
-    gwbuf_free(p->stored_query);
-
-    p->protocol_state = MYSQL_PROTOCOL_DONE;
-
-retblock:
-    spinlock_release(&p->protocol_lock);
 }
 
 /**
@@ -660,8 +654,6 @@ void protocol_archive_srv_command(MySQLProtocol* p)
 
     CHK_PROTOCOL(p);
 
-    spinlock_acquire(&p->protocol_lock);
-
     if (p->protocol_state != MYSQL_PROTOCOL_ACTIVE)
     {
         goto retblock;
@@ -710,7 +702,6 @@ void protocol_archive_srv_command(MySQLProtocol* p)
     }
 
 retblock:
-    spinlock_release(&p->protocol_lock);
     CHK_PROTOCOL(p);
 }
 
@@ -725,11 +716,10 @@ void protocol_add_srv_command(MySQLProtocol*     p,
 #if defined(EXTRA_SS_DEBUG)
     server_command_t* c;
 #endif
-    spinlock_acquire(&p->protocol_lock);
 
     if (p->protocol_state != MYSQL_PROTOCOL_ACTIVE)
     {
-        goto retblock;
+        return;
     }
     /** this is the only server command in protocol */
     if (p->protocol_command.scom_cmd == MYSQL_COM_UNDEFINED)
@@ -758,8 +748,6 @@ void protocol_add_srv_command(MySQLProtocol*     p,
         c = c->scom_next;
     }
 #endif
-retblock:
-    spinlock_release(&p->protocol_lock);
 }
 
 
@@ -772,7 +760,7 @@ retblock:
 void protocol_remove_srv_command(MySQLProtocol* p)
 {
     server_command_t* s;
-    spinlock_acquire(&p->protocol_lock);
+
     s = &p->protocol_command;
 #if defined(EXTRA_SS_DEBUG)
     MXS_INFO("Removed command %s from fd %d.",
@@ -788,8 +776,6 @@ void protocol_remove_srv_command(MySQLProtocol* p)
         p->protocol_command = *(s->scom_next);
         MXS_FREE(s->scom_next);
     }
-
-    spinlock_release(&p->protocol_lock);
 }
 
 mysql_server_cmd_t protocol_get_srv_command(MySQLProtocol* p,
@@ -889,10 +875,8 @@ bool protocol_get_response_status(MySQLProtocol* p,
 
     CHK_PROTOCOL(p);
 
-    spinlock_acquire(&p->protocol_lock);
     *npackets = p->protocol_command.scom_nresponse_packets;
     *nbytes   = (ssize_t)p->protocol_command.scom_nbytes_to_read;
-    spinlock_release(&p->protocol_lock);
 
     if (*npackets < 0 && *nbytes == 0)
     {
@@ -912,14 +896,10 @@ void protocol_set_response_status(MySQLProtocol* p,
 {
     CHK_PROTOCOL(p);
 
-    spinlock_acquire(&p->protocol_lock);
-
     p->protocol_command.scom_nbytes_to_read = nbytes;
     ss_dassert(p->protocol_command.scom_nbytes_to_read >= 0);
 
     p->protocol_command.scom_nresponse_packets = npackets_left;
-
-    spinlock_release(&p->protocol_lock);
 }
 
 char* create_auth_failed_msg(GWBUF*readbuf,

server/modules/routing/maxinfo/maxinfo.c

@@ -291,20 +291,15 @@ static void handleError(MXS_ROUTER     *instance,
     {
         backend_dcb->dcb_errhandle_called = true;
     }
-    spinlock_acquire(&session->ses_lock);
+
     sesstate = session->state;
     client_dcb = session->client_dcb;
 
     if (sesstate == SESSION_STATE_ROUTER_READY)
     {
         CHK_DCB(client_dcb);
-        spinlock_release(&session->ses_lock);
         client_dcb->func.write(client_dcb, gwbuf_clone(errbuf));
     }
-    else
-    {
-        spinlock_release(&session->ses_lock);
-    }
 
     /** false because connection is not available anymore */
     dcb_close(backend_dcb);

server/modules/routing/readconnroute/readconnroute.c

@@ -82,7 +82,6 @@
 #include <maxscale/atomic.h>
 #include <maxscale/spinlock.h>
 #include <maxscale/dcb.h>
-#include <maxscale/spinlock.h>
 #include <maxscale/modinfo.h>
 #include <maxscale/log_manager.h>
 #include <maxscale/protocol/mysql.h>
@@ -105,9 +104,6 @@ static void rses_end_locked_router_action(ROUTER_CLIENT_SES* rses);
 static SERVER_REF *get_root_master(SERVER_REF *servers);
 static int handle_state_switch(DCB* dcb, DCB_REASON reason, void * routersession);
 
-static SPINLOCK instlock;
-static ROUTER_INSTANCE *instances;
-
 /**
  * The module entry point routine. It is this routine that
  * must populate the structure that is referred to as the
@@ -119,8 +115,6 @@ static ROUTER_INSTANCE *instances;
 MXS_MODULE* MXS_CREATE_MODULE()
 {
     MXS_NOTICE("Initialise readconnroute router module.");
-    spinlock_init(&instlock);
-    instances = NULL;
 
     static MXS_ROUTER_OBJECT MyObject =
     {
@@ -252,10 +246,6 @@ createInstance(SERVICE *service, char **options)
      * insert this router instance into the linked list of routers
      * that have been created with this module.
      */
-    spinlock_acquire(&instlock);
-    inst->next = instances;
-    instances = inst;
-    spinlock_release(&instlock);
 
     return (MXS_ROUTER *) inst;
 }
@@ -710,20 +700,16 @@ static void handleError(MXS_ROUTER *instance, void *router_session, GWBUF *errbu
     {
         problem_dcb->dcb_errhandle_called = true;
     }
-    spinlock_acquire(&session->ses_lock);
+
     sesstate = session->state;
     client_dcb = session->client_dcb;
 
     if (sesstate == SESSION_STATE_ROUTER_READY)
     {
         CHK_DCB(client_dcb);
-        spinlock_release(&session->ses_lock);
+
         client_dcb->func.write(client_dcb, gwbuf_clone(errbuf));
     }
-    else
-    {
-        spinlock_release(&session->ses_lock);
-    }
 
     if (DCB_ROLE_CLIENT_HANDLER == problem_dcb->dcb_role)
     {

server/modules/routing/readwritesplit/readwritesplit.c

@@ -1535,10 +1535,8 @@ static void handle_error_reply_client(MXS_SESSION *ses, ROUTER_CLIENT_SES *rses,
     DCB *client_dcb;
     backend_ref_t *bref;
 
-    spinlock_acquire(&ses->ses_lock);
     sesstate = ses->state;
     client_dcb = ses->client_dcb;
-    spinlock_release(&ses->ses_lock);
 
     if ((bref = get_bref_from_dcb(rses, backend_dcb)) != NULL)
     {

server/modules/routing/schemarouter/schemarouter.c

@@ -860,8 +860,6 @@ static void* newSession(MXS_ROUTER* router_inst, MXS_SESSION* session)
     bool using_db = false;
     bool have_db = false;
 
-    spinlock_acquire(&session->ses_lock);
-
     /* To enable connecting directly to a sharded database we first need
      * to disable it for the client DCB's protocol so that we can connect to them*/
     if (protocol->client_capabilities & GW_MYSQL_CAPABILITIES_CONNECT_WITH_DB &&
@@ -880,8 +878,6 @@ static void* newSession(MXS_ROUTER* router_inst, MXS_SESSION* session)
         MXS_INFO("Client'%s' connecting with empty database.", data->user);
     }
 
-    spinlock_release(&session->ses_lock);
-
     client_rses = (ROUTER_CLIENT_SES *)MXS_CALLOC(1, sizeof(ROUTER_CLIENT_SES));
 
     if (client_rses == NULL)
@@ -3647,10 +3643,8 @@ static void handle_error_reply_client(MXS_SESSION*       ses,
     DCB* client_dcb;
     backend_ref_t*  bref;
 
-    spinlock_acquire(&ses->ses_lock);
     sesstate = ses->state;
     client_dcb = ses->client_dcb;
-    spinlock_release(&ses->ses_lock);
 
     /**
      * If bref exists, mark it closed