[src/trunk]: src/sys/external/bsd/drm2/drm CLFLUSH needs to be surrounded by ...

[riastradh <riastradh%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/a1bee8ec4e50
branches:  trunk
changeset: 336520:a1bee8ec4e50
user:      riastradh <riastradh%NetBSD.org@localhost>
date:      Wed Mar 04 18:19:27 2015 +0000

description:
CLFLUSH needs to be surrounded by membars.

While here, round everything to a multiple of the cache line size.

diffstat:

 sys/external/bsd/drm2/drm/drm_cache.c |  14 +++++++++-----
 1 files changed, 9 insertions(+), 5 deletions(-)

diffs (41 lines):

diff -r f59468b42591 -r a1bee8ec4e50 sys/external/bsd/drm2/drm/drm_cache.c
--- a/sys/external/bsd/drm2/drm/drm_cache.c     Wed Mar 04 17:02:17 2015 +0000
+++ b/sys/external/bsd/drm2/drm/drm_cache.c     Wed Mar 04 18:19:27 2015 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: drm_cache.c,v 1.3 2014/07/16 20:56:25 riastradh Exp $  */
+/*     $NetBSD: drm_cache.c,v 1.4 2015/03/04 18:19:27 riastradh Exp $  */
 
 /*-
  * Copyright (c) 2013 The NetBSD Foundation, Inc.
@@ -30,7 +30,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: drm_cache.c,v 1.3 2014/07/16 20:56:25 riastradh Exp $");
+__KERNEL_RCSID(0, "$NetBSD: drm_cache.c,v 1.4 2015/03/04 18:19:27 riastradh Exp $");
 
 #include <sys/types.h>
 #include <sys/xcall.h>
@@ -146,15 +146,19 @@
 
 static void
 drm_md_clflush_virt_range(const void *vaddr, size_t nbytes)
-
 {
-       const char *const start = vaddr, *const end = (start + nbytes);
+       const unsigned clflush_size = drm_x86_clflush_size();
+       const vaddr_t va = (vaddr_t)vaddr;
+       const char *const start = (const void *)rounddown(va, clflush_size);
+       const char *const end = (const void *)roundup(va + nbytes,
+           clflush_size);
        const char *p;
-       const unsigned int clflush_size = drm_x86_clflush_size();
 
        KASSERT(drm_md_clflush_finegrained_p());
+       membar_sync();
        for (p = start; p < end; p += clflush_size)
                drm_x86_clflush(p);
+       membar_sync();
 }
 
 #endif /* defined(__i386__) || defined(__x86_64__) */