5 Replies Latest reply on Jan 2, 2012 10:08 AM by tedk

    Are flag writes broadcast?




      I have made an experiment, in which Core 0 sets a flag from UNSET to SET, and the target is Core 5.

      Stuff happens, and all cores reach a barrier.

      Now when each of the core reads the flag, and the target is RCCE_ue() - they see the SET.


      Example code:


      if (ME==0)

           RCCE_flag_write (&flg, RCCE_FLAG_SET, 5);  /* Core 0 sets flg in core 5 */


      RCCE_flag_read (&flg, &tmp_flg_val, ME);  /* Each core reads its own MPB! */

      if (tmp_flg_val == RCCE_FLAG_SET)

           printf ("Merry Christmas!\n");


      ... All cores shout "Merry Christmas!".

      And I ask:

      How do all cores know what core 0 wrote in core 5's MPB?

      Are flag writes broadcast?


      Thanks and merry christmas,