Assertion for repeated callbacks with UA_MULTITHREADING=100

[basyskom-jvoe]

Description

Servers built with open62541 1.2 with UA_MULTITHREADING=100 terminate sporadically with the following message:
/home/jvoe/open62541/src/server/ua_server.c:670: serverExecuteRepeatedCallback: Assertion `server->serviceMutexCounter == 0' failed.

Background Information / Reproduction Steps

Build the open62541 1.2 branch with the following CMake options

cmake -DUA_ENABLE_ENCRYPTION:BOOL="1" -DUA_NAMESPACE_ZERO:STRING="FULL" -DUA_ENABLE_AMALGAMATION:BOOL="0" -DUA_ENABLE_SUBSCRIPTIONS_EVENTS:BOOL="1" -DUA_ENABLE_ENCRYPTION_OPENSSL:BOOL="1" -DUA_MULTITHREADING:STRING="100"

and link it to a server with one active repeated callback.

Checklist

Please provide the following information:

[X ] open62541 Version (release number or git tag): 1.2 (e401ddf)

[rexsum]

This issue looks similar to the one that I reported yesterday (issue: 4119). it looks like code was pushed that is causing these multi-threading assert errors to suddenly start showing up. I'd like for whomever it is that reviews these issues to be aware that this is a problem that needs to be addressed.

[jpfr]

Please provide a backtrace from a debugger.
Should be easy to fix then.

[basyskom-jvoe]

The error seems to occur less often when a debugger is attached. Finally, after a few hours, it happened:

#1  0x00007ffff681403a in __GI_abort () at abort.c:89
#2  0x00007ffff680abe7 in __assert_fail_base (fmt=<optimized out>, assertion=assertion@entry=0x8d4040 "server->serviceMutexCounter == 0", 
    file=file@entry=0x8d3e60 "/home/jvoe/open62541/src/server/ua_server.c", line=line@entry=670, 
    function=function@entry=0x8d41d0 <__PRETTY_FUNCTION__.18338> "serverExecuteRepeatedCallback") at assert.c:92
#3  0x00007ffff680ac92 in __GI___assert_fail (assertion=0x8d4040 "server->serviceMutexCounter == 0", file=0x8d3e60 "/home/jvoe/open62541/src/server/ua_server.c", 
    line=670, function=0x8d41d0 <__PRETTY_FUNCTION__.18338> "serverExecuteRepeatedCallback") at assert.c:101
#4  0x00000000004af190 in serverExecuteRepeatedCallback (server=0xc1fb90, cb=0x881a1e <publishCallback>, callbackApplication=0xc1fb90, data=0x1410010)
    at /home/jvoe/open62541/src/server/ua_server.c:670
#5  0x00000000008962c2 in UA_Timer_process (t=0xc200e8, nowMonotonic=6150398231133, executionCallback=0x4af14b <serverExecuteRepeatedCallback>, 
    executionApplication=0xc1fb90) at /home/jvoe/open62541/src/ua_timer.c:207
#6  0x00000000004af1e6 in UA_Server_run_iterate (server=0xc1fb90, waitInternal=true) at /home/jvoe/open62541/src/server/ua_server.c:678
#7  0x00000000004af489 in UA_Server_run (server=0xc1fb90, running=0xbcc814 <running>) at /home/jvoe/open62541/src/server/ua_server.c:773
#8  0x0000000000484808 in MyServer::run(bool volatile*) ()
#9  0x000000000044b661 in main ()