Re: Redundancy Patch: db

[Andrew Johnson <anj@aps.anl.gov>]

Andrew Johnson wrote:
> **************
> Modified
> **************
>
> # source files
> (1) base-3.14.9/src/db/dbAccess.c
>     dbPutSpecial() is added for CCE. This function is just a pipe to
>     call the static function putSpecial(). dbPutSpecial() is written
>     by John L. Dalesio and Bernd Schoeneburg originally.
Rather than add a new function, rename the existing static
putSpecial() function to dbPutSpecial() and remove the static
keyword.  All callers to the static putSpecial() routine are local to
this source file.


> (2) base-3.14.9/src/db/dbScan.c
>     Register periodic scan tasks at RMT. When the IOC is SLAVE, these
>     tasks are changed to be inactive.
The #ifndef vxWorks block will not be accepted.

The changes here that provide the ability to stop periodic scan tasks
represent functionality that should be part of Base, although I may
want to change their implementation somewhat.

The code that registers the periodic scan tasks with the RMT should be
replaced with a call through a global function pointer that the RMT
initialization code can set before iocInit().  By removing any need
for the scan code to perform the registration itself this also drops
the requirement for epicsFindSymbol() and for the rmtDrvIf.h header to
be included in Base.


> (3) base-3.14.9/src/dbStatic/dbBase.h
>     enum type "redUp" and the element of struct dbFldDes "red_update"
>     are added for CCE. They are added by Bernd Schoeneburg originally.
>
> (4) base-3.14.9/src/dbStatic/dbLexRoutines.c
>     Deal with pdbFldDes->red_update for CCE, by Bernd Schoeneburg
>     originally.
This change adds 2 bytes to the field description structure of every 
field of every record type in every IOC (that's about 1.7 KBytes for all 
the record types in Base, which will be completely wasted on IOCs that 
are not redundant) and provides the means for these values to be set 
from the DBD file that defines the record type.  We might want to 
include a switch in the site configuration to turn on/off whether this 
structure should include the red_update field.
I note that you did not include any modified record.dbd files; was that 
an oversight, or do redundant IOCs have to use a completely different 
set of record types?  If you have to add a redUp() line to any of the 
base record.dbd files then those changes need to go into Base too — you 
should never use a record.dbd file in an IOC if a different record.dbd 
file was used to generate the record.h file.

> **************
> Added
> **************
> (1) base-3.14.9/src/db/rmtDrvIf.h
>     The head file for RMT driver interface.
This header is not required if the task registration code is moved into 
the redundancy application and hooked into the IOC by setting a global 
function pointer before iocInit().  In any case it also appears in the 
rsrv patch; only one instance of any header file should be included.
- Andrew
--
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