On Mon, 12 May 2014, Christoph Lameter wrote: > > V4->V5: > - Shepherd thread on a specific cpu (HOUSEKEEPING_CPU). That's going to fail for the NOHZ_IDLE case, e.g. for the little/big cluster support on ARM. They need to be able to move it from the housekeeper on the big to the housekeeper on the little cluster. So as I said before: This wants to be on a dedicated housekeeper workqueue. Where the thread is placed is decided by the core depending on system configuration and state. nohz = off CPU0 nohz = idle core decision depending on state nohz = full CPU0 Your solution solves only the off and full case and will fail when in the idle case CPU0 should be sent into deep idle sleep until the user decides to do some work which requires CPU0 to come back. Thanks, tglx -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>