[src/trunk]: src/sys/external/bsd/drm2/dist/drm/nouveau Attempt to make sense...

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

details:   https://anonhg.NetBSD.org/src/rev/1f8bfd403b9d
branches:  trunk
changeset: 365591:1f8bfd403b9d
user:      riastradh <riastradh%NetBSD.org@localhost>
date:      Thu Aug 23 01:10:28 2018 +0000

description:
Attempt to make sense of return values of nouveau_fence_wait.

PR kern/53441

XXX pullup-7
XXX pullup-8

diffstat:

 sys/external/bsd/drm2/dist/drm/nouveau/nouveau_fence.c |  26 +++++++++++++----
 1 files changed, 19 insertions(+), 7 deletions(-)

diffs (62 lines):

diff -r ea51861bf6a5 -r 1f8bfd403b9d sys/external/bsd/drm2/dist/drm/nouveau/nouveau_fence.c
--- a/sys/external/bsd/drm2/dist/drm/nouveau/nouveau_fence.c    Thu Aug 23 01:10:21 2018 +0000
+++ b/sys/external/bsd/drm2/dist/drm/nouveau/nouveau_fence.c    Thu Aug 23 01:10:28 2018 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: nouveau_fence.c,v 1.7 2018/08/23 01:10:21 riastradh Exp $      */
+/*     $NetBSD: nouveau_fence.c,v 1.8 2018/08/23 01:10:28 riastradh Exp $      */
 
 /*
  * Copyright (C) 2007 Ben Skeggs.
@@ -27,7 +27,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: nouveau_fence.c,v 1.7 2018/08/23 01:10:21 riastradh Exp $");
+__KERNEL_RCSID(0, "$NetBSD: nouveau_fence.c,v 1.8 2018/08/23 01:10:28 riastradh Exp $");
 
 #include <sys/types.h>
 #include <sys/xcall.h>
@@ -446,6 +446,9 @@
  *
  *     Wait using a nouveau event for completion of fence on chan.
  *     Wait interruptibly iff intr is true.
+ *
+ *     Return 0 if fence was signalled, negative error code on
+ *     timeout (-EBUSY) or interrupt (-ERESTARTSYS) or other error.
  */
 static int
 nouveau_fence_wait_uevent(struct nouveau_fence *fence,
@@ -487,12 +490,18 @@
                        }
                        nouveau_fence_gc_grab(fctx, &done_list);
                        spin_unlock(&fctx->lock);
-               }
-
-               if (ret >= 0) {
-                       fence->timeout = jiffies + ret;
-                       if (time_after_eq(jiffies, fence->timeout))
+                       if (ret < 0) {
+                               /* error */
+                       } else if (ret == 0) {
+                               /* timeout */
                                ret = -EBUSY;
+                       } else {
+                               /* success */
+                               ret = 0;
+                       }
+               } else {
+                       /* timeout */
+                       ret = -EBUSY;
                }
        } else {
                spin_lock(&fctx->lock);
@@ -525,6 +534,9 @@
  *     Wait for fence to complete.  Wait interruptibly iff intr is
  *     true.  If lazy is true, may sleep, either for a single tick or
  *     for an interrupt; otherwise will busy-wait.
+ *
+ *     Return 0 if fence was signalled, negative error code on
+ *     timeout (-EBUSY) or interrupt (-ERESTARTSYS) or other error.
  */
 int
 nouveau_fence_wait(struct nouveau_fence *fence, bool lazy, bool intr)