Do avro conversion in main thread

The avrorouter no longer uses the housekeeper for the conversion
task. This prevents the deadlock which could occur when clients were
notified at the same time that the binlogrouter was adding a master
reconnection task.

server/modules/routing/avrorouter/avro.cc

@@ -33,7 +33,6 @@
 #include <maxscale/alloc.h>
 #include <maxscale/atomic.h>
 #include <maxscale/dcb.h>
-#include <maxscale/housekeeper.h>
 #include <maxscale/log_manager.h>
 #include <maxscale/modulecmd.h>
 #include <maxscale/paths.h>
@@ -44,15 +43,18 @@
 #include <maxscale/service.h>
 #include <maxscale/spinlock.h>
 #include <maxscale/utils.h>
+#include <maxscale/routingworker.h>
+#include <maxscale/worker.hh>
 #include <binlog_common.h>
 
+using namespace maxscale;
+
 #ifndef BINLOG_NAMEFMT
 #define BINLOG_NAMEFMT      "%s.%06d"
 #endif
 
 #define AVRO_TASK_DELAY_MAX 15
 
-static const char* avro_task_name = "binlog_to_avro";
 static const char* index_task_name = "avro_indexing";
 static const char* avro_index_name = "avro.index";
 
@@ -77,7 +79,7 @@ static void errorReply(MXS_ROUTER *instance, MXS_ROUTER_SESSION *router_session,
 static uint64_t getCapabilities(MXS_ROUTER* instance);
 extern int MaxScaleUptime();
 extern void avro_get_used_tables(Avro *router, DCB *dcb);
-bool converter_func(void* data);
+bool converter_func(Worker::Call::action_t action, Avro* router);
 bool binlog_next_file_exists(const char* binlogdir, const char* binlog);
 int blr_file_get_next_binlogname(const char *router);
 bool avro_load_conversion_state(Avro *router);
@@ -363,15 +365,17 @@ static bool conversion_task_ctl(Avro *inst, bool start)
 
     if (!inst->service->svc_do_shutdown)
     {
-        char tasknm[strlen(avro_task_name) + strlen(inst->service->name) + 2];
+        Worker* worker = static_cast<Worker*>(mxs_rworker_get(MXS_RWORKER_MAIN));
-        snprintf(tasknm, sizeof(tasknm), "%s-%s", inst->service->name, avro_task_name);
 
-        /** Remove old task and create a new one */
+        if (inst->task_handle)
-        hktask_remove(tasknm);
+        {
+            worker->cancel_delayed_call(inst->task_handle);
+            inst->task_handle = 0;
+        }
 
         if (start)
         {
-            hktask_add(tasknm, converter_func, inst, inst->task_delay);
+            inst->task_handle = worker->delayed_call(inst->task_delay * 1000, converter_func, inst);
         }
 
         rval = true;
@@ -643,14 +647,6 @@ createInstance(SERVICE *service, char **options)
     avro_load_conversion_state(inst);
     avro_load_metadata_from_schemas(inst);
 
-    /*
-     * Add tasks for statistic computation
-     */
-    /** Not used currenly
-    snprintf(task_name, BLRM_TASK_NAME_LEN, "%s stats", service->name);
-    hktask_add(task_name, stats_func, inst, AVRO_STATS_FREQ);
-     */
-
     /* Start the scan, read, convert AVRO task */
     conversion_task_ctl(inst, true);
 
@@ -901,9 +897,13 @@ static uint64_t getCapabilities(MXS_ROUTER* instance)
 /**
  * Conversion task: MySQL binlogs to AVRO files
  */
-bool converter_func(void* data)
+bool converter_func(Worker::Call::action_t action, Avro* router)
 {
-    Avro* router = (Avro*) data;
+    if (action == Worker::Call::CANCEL)
+    {
+        return false;
+    }
+
     bool ok = true;
     avro_binlog_end_t binlog_end = AVRO_OK;
 

server/modules/routing/avrorouter/avrorouter.hh

@@ -229,6 +229,7 @@ struct Avro
                                           * a flush of all tables */
     uint64_t                 block_size; /**< Avro datablock size */
     enum mxs_avro_codec_type codec; /**< Avro codec type, defaults to `null` */
+    uint32_t                 task_handle; /**< Delayed task handle */
 };
 
 struct AvroSession