CVS commit: src/sys/external/bsd/common/include/asm

["Taylor R Campbell" <riastradh%netbsd.org@localhost>]

Module Name:    src
Committed By:   riastradh
Date:           Sun Jul 17 18:45:48 UTC 2022

Modified Files:
        src/sys/external/bsd/common/include/asm: barrier.h

Log Message:
drm: Comment *mb() vs smp_*mb() and omit default for *mb().

In general membar_*() is _not_ enough for *mb(), because membar_*()
is only for CPU/CPU synchronization on normal memory, and *mb()
requires machine-dependent I/O logic.  Leave it as an `#error' case
if the architecture isn't listed here.  But membar_*() is OK for
smp_*().

Fill in powerpc and sparc while here, as examples of what the
now-removed defaults failed to do.  If you want to use drm on a mips
or alpha system yer gonna hafta fill this in yourself.


To generate a diff of this commit:
cvs rdiff -u -r1.13 -r1.14 src/sys/external/bsd/common/include/asm/barrier.h

Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.