On Sat, Dec 15, 2018 at 05:48:48PM -0800, yupeng wrote:

The trace.c could only be used by core.c, move it to a header file and
then other nvme modules could also use it. This commit creates a new
header file trace_common.h, which has all the functions of trace.c. It
changes all functions to static functions, so any other modules could
include it without conflict. This commit also moves some common
functions from trace.h to trace_common.h. Because the trace events in
trace.h are used by nvme-core only, this commit renames the trace.h to
trace_core.h.

We could always export bits out of trace.o using EXPORT_SYMBOL_GPL,
no need to move duplicate the code.  Also as far as I can tell you
only use __assign_disk_name of the helpers, so we can move that into
a new helper.  It might make sense to just move that into
include/linux/genhd.h to make it easily available everywhere.