How to manually update the cache data from the SDRAM?

Hi!

  I allocate some share-memory in SDRAM between core0 and core1 on BF609, and the data cache policy in buildroot is set to "write through".
  But sometimes I found that the data been read in core0 was different with the data been written in core1. I thought "data cache" policy may cause the problem.
  So, I want to update the cache data from SDRAM everytime reading share-data in core0. Is there some "functions" in C-lanuage which can do this job?

Thanks.