Bus space barriers (XCC)
authorBarret Rhoden <brho@cs.berkeley.edu>
Fri, 16 Jan 2015 00:12:39 +0000 (16:12 -0800)
committerBarret Rhoden <brho@cs.berkeley.edu>
Sun, 1 Mar 2015 14:36:00 +0000 (09:36 -0500)
commitd6a647796f9702527680e86c62e61ab5dcaf57e9
treebc4e26463ec8be48a5bfb3946ecb446494dba967
parenta0939fb5ef4f9014cacc838b3dc55444ca04e9f6
Bus space barriers (XCC)

On x86, a LOCK will flush the write buffers.  This is what BSD does under the
hood for their bus_space_barriers.  I don't know when the LOCKs should be used
compared to lfence/sfence/mfence.

Technically, these are kernel headers we're messing with (the membar), but
don't worry about it.
kern/arch/riscv/ros/membar.h
kern/arch/x86/ros/membar.h