Merge ~dirk.zimoch/epics-base:InitEventFreelistsEarly into ~epics-core/epics-base/+git/epics-base:3.15

[Dirk Zimoch]

This change allows to use the event freelists in dbChannel before Channel Access has started (i.e. during PINI).

[Andrew Johnson (anj)]

Hi Dirk,

I believe I have said this before: We have a general rule that new features get added to the 7.0 branch, while bug fixes get applied to the earliest branch that suffers from the bug (often but not always 3.15 nowadays).

Your dbDbLink changes are adding a new feature and were thus correctly proposed for merging into the 7.0 branch (don't try to rebase them against 3.15, except for any bug-fixes which should be discussed separately). Please rebase the changes here against 7.0 where they belong.

Thanks,

- Andrew

[Dirk Zimoch (dirk.zimoch)]

I thought we had agreed on moving the dbDbLink changes to 3.15, because that is where filters had been introduced ???

I can continue to work on the 7.0 branch of course, but please make sure that there is a consensus in the core team first, as rebasing this is not a simple work (files have been moved around, functionality has been moved to other files).

[Dirk Zimoch (dirk.zimoch)]

Superseded by https://code.launchpad.net/~dirk.zimoch/epics-base/+git/epics-base/+merge/378968

Unmerged commits

f3f873a... by Dirk Zimoch on 2020-02-24

initialize free lists when starting dbChannel

diff --git a/src/ioc/db/dbChannel.c b/src/ioc/db/dbChannel.c
index 399d13d..f355af9 100644
--- a/src/ioc/db/dbChannel.c
+++ b/src/ioc/db/dbChannel.c
@@ -67,6 +67,7 @@ void dbChannelInit (void)
     freeListInitPvt(&dbChannelFreeList,  sizeof(dbChannel), 128);
     freeListInitPvt(&chFilterFreeList,  sizeof(chFilter), 64);
     freeListInitPvt(&dbchStringFreeList, sizeof(epicsOldString), 128);
+    db_init_event_freelists();
 }
 
 static void chf_value(parseContext *parser, parse_result *presult)
diff --git a/src/ioc/db/dbEvent.c b/src/ioc/db/dbEvent.c
index d1f9548..f89c685 100644
--- a/src/ioc/db/dbEvent.c
+++ b/src/ioc/db/dbEvent.c
@@ -153,7 +153,7 @@ int dbel ( const char *pname, unsigned level )
     if ( ! pname ) return DB_EVENT_OK;
     status = dbNameToAddr ( pname, &addr );
     if ( status != 0 ) {
-	    errMessage ( status, " dbNameToAddr failed" );
+        errMessage ( status, " dbNameToAddr failed" );
         return DB_EVENT_ERROR;
     }
 
@@ -162,7 +162,7 @@ int dbel ( const char *pname, unsigned level )
     pevent = (struct evSubscrip *) ellFirst ( &addr.precord->mlis );
 
     if ( ! pevent ) {
-	    printf ( "\"%s\": No PV event subscriptions ( monitors ).\n", pname );
+        printf ( "\"%s\": No PV event subscriptions ( monitors ).\n", pname );
         UNLOCKREC (addr.precord);
         return DB_EVENT_OK;
     }
@@ -174,14 +174,14 @@ int dbel ( const char *pname, unsigned level )
         pdbFldDes = dbChannelFldDes(pevent->chan);
 
         if ( level > 0 ) {
-	        printf ( "%4.4s", pdbFldDes->name );
+            printf ( "%4.4s", pdbFldDes->name );
 
-	        printf ( " { " );
+            printf ( " { " );
                 if ( pevent->select & DBE_VALUE ) printf( "VALUE " );
                 if ( pevent->select & DBE_LOG ) printf( "LOG " );
                 if ( pevent->select & DBE_ALARM ) printf( "ALARM " );
                 if ( pevent->select & DBE_PROPERTY ) printf( "PROPERTY " );
-	        printf ( "}" );
+            printf ( "}" );
 
             if ( pevent->npend ) {
                 printf ( " undelivered=%ld", pevent->npend );
@@ -236,7 +236,7 @@ int dbel ( const char *pname, unsigned level )
                     ( void * ) pevent->ev_que->evUser );
             }
 
-	        printf( "\n" );
+            printf( "\n" );
         }
 
             pevent = (struct evSubscrip *) ellNext ( &pevent->node );
@@ -247,23 +247,17 @@ int dbel ( const char *pname, unsigned level )
     return DB_EVENT_OK;
 }
 
+
 /*
- * DB_INIT_EVENTS()
+ * DB_INIT_EVENT_FREELISTS()
  *
  *
- * Initialize the event facility for this task. Must be called at least once
- * by each task which uses the db event facility
+ * Initialize the free lists used by the event facility.
+ * Safe to be called multiple times.
  *
- * returns: ptr to event user block or NULL if memory can't be allocated
  */
-dbEventCtx db_init_events (void)
+void db_init_event_freelists (void)
 {
-    struct event_user * evUser;
-
-    if (!stopSync) {
-        stopSync = epicsMutexMustCreate();
-    }
-
     if (!dbevEventUserFreeList) {
         freeListInitPvt(&dbevEventUserFreeList,
             sizeof(struct event_user),8);
@@ -280,6 +274,26 @@ dbEventCtx db_init_events (void)
         freeListInitPvt(&dbevFieldLogFreeList,
             sizeof(struct db_field_log),2048);
     }
+}
+
+/*
+ * DB_INIT_EVENTS()
+ *
+ *
+ * Initialize the event facility for this task. Must be called at least once
+ * by each task which uses the db event facility
+ *
+ * returns: ptr to event user block or NULL if memory can't be allocated
+ */
+dbEventCtx db_init_events (void)
+{
+    struct event_user * evUser;
+
+    if (!stopSync) {
+        stopSync = epicsMutexMustCreate();
+    }
+
+    db_init_event_freelists();
 
     evUser = (struct event_user *)
         freeListCalloc(dbevEventUserFreeList);
@@ -381,7 +395,7 @@ void db_close_events (dbEventCtx ctx)
  */
 static struct event_que * create_ev_que ( struct event_user * const evUser )
 {
-    struct event_que * const ev_que = (struct event_que *) 
+    struct event_que * const ev_que = (struct event_que *)
         freeListCalloc ( dbevEventQueueFreeList );
     if ( ! ev_que ) {
         return NULL;
@@ -425,7 +439,7 @@ dbEventSubscription db_add_event (
     while ( TRUE ) {
         int success = 0;
         LOCKEVQUE ( ev_que );
-        success = ( ev_que->quota + ev_que->nCanceled < 
+        success = ( ev_que->quota + ev_que->nCanceled <
                                 EVENTQUESIZE - EVENTENTRIES );
         if ( success ) {
             ev_que->quota += EVENTENTRIES;
@@ -1093,7 +1107,7 @@ int db_start_events (
          taskname = EVENT_PEND_NAME;
      }
      evUser->taskid = epicsThreadCreate (
-         taskname, osiPriority, 
+         taskname, osiPriority,
          epicsThreadGetStackSize(epicsThreadStackMedium),
          event_task, (void *)evUser);
      if (!evUser->taskid) {
@@ -1108,7 +1122,7 @@ int db_start_events (
 /*
  * db_event_change_priority()
  */
-void db_event_change_priority ( dbEventCtx ctx, 
+void db_event_change_priority ( dbEventCtx ctx,
                                         unsigned epicsPriority )
 {
     struct event_user * const evUser = ( struct event_user * ) ctx;
diff --git a/src/ioc/db/dbEvent.h b/src/ioc/db/dbEvent.h
index 2e496a7..7fc6198 100644
--- a/src/ioc/db/dbEvent.h
+++ b/src/ioc/db/dbEvent.h
@@ -50,6 +50,7 @@ epicsShareFunc int db_post_events (
 typedef void * dbEventCtx;
 
 typedef void EXTRALABORFUNC (void *extralabor_arg);
+void db_init_event_freelists (void);
 epicsShareFunc dbEventCtx db_init_events (void);
 epicsShareFunc int db_start_events (
     dbEventCtx ctx, const char *taskname, void (*init_func)(void *),
@@ -64,7 +65,7 @@ epicsShareFunc int db_post_extra_labor (dbEventCtx ctx);
 epicsShareFunc void db_event_change_priority ( dbEventCtx ctx, unsigned epicsPriority );
 
 typedef void EVENTFUNC (void *user_arg, struct dbChannel *chan,
-	int eventsRemaining, struct db_field_log *pfl);
+    int eventsRemaining, struct db_field_log *pfl);
 
 typedef void * dbEventSubscription;
 epicsShareFunc dbEventSubscription db_add_event (