[src/trunk]: src/sys/external/bsd/drm2/include/drm Another attempt to fix the...

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

details:   https://anonhg.NetBSD.org/src/rev/602d3d0800ec
branches:  trunk
changeset: 336355:602d3d0800ec
user:      riastradh <riastradh%NetBSD.org@localhost>
date:      Thu Feb 26 23:27:41 2015 +0000

description:
Another attempt to fix the drm timed wait blarf blugh blahhh.

diffstat:

 sys/external/bsd/drm2/include/drm/drm_wait_netbsd.h |  29 +++++++++++++++++---
 1 files changed, 24 insertions(+), 5 deletions(-)

diffs (69 lines):

diff -r 19df0ca3b94b -r 602d3d0800ec sys/external/bsd/drm2/include/drm/drm_wait_netbsd.h
--- a/sys/external/bsd/drm2/include/drm/drm_wait_netbsd.h       Thu Feb 26 23:00:05 2015 +0000
+++ b/sys/external/bsd/drm2/include/drm/drm_wait_netbsd.h       Thu Feb 26 23:27:41 2015 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: drm_wait_netbsd.h,v 1.5 2014/08/26 00:48:29 riastradh Exp $    */
+/*     $NetBSD: drm_wait_netbsd.h,v 1.6 2015/02/26 23:27:41 riastradh Exp $    */
 
 /*-
  * Copyright (c) 2013 The NetBSD Foundation, Inc.
@@ -129,6 +129,19 @@
 #define        DRM_WAIT_UNTIL(RET, Q, I, C)                            \
        _DRM_WAIT_UNTIL(RET, cv_wait_sig, Q, I, C)
 
+/*
+ * Timed wait.  Return:
+ *
+ * - 0 if condition is false after timeout,
+ * - 1 if condition is true after timeout or one tick before timeout,
+ * - number of ticks left if condition evaluated to true before timeout, or
+ * - error if failure (e.g., interrupted).
+ *
+ * XXX Comments in Linux say it returns -ERESTARTSYS if interrupted.
+ * What if by a signal without SA_RESTART?  Shouldn't it be -EINTR
+ * then?  I'm going to leave it as what cv_timedwait returned, which is
+ * ERESTART for signals with SA_RESTART and EINTR otherwise.
+ */
 #define        _DRM_TIMED_WAIT_UNTIL(RET, WAIT, Q, INTERLOCK, TICKS, CONDITION) do \
 {                                                                      \
        extern int hardclock_ticks;                                     \
@@ -145,14 +158,17 @@
                /* XXX errno NetBSD->Linux */                           \
                (RET) = -WAIT((Q), &(INTERLOCK)->mtx_lock,              \
                    _dtwu_ticks);                                       \
-               if (RET)                                                \
+               if (RET) {                                              \
+                       if ((RET) == -EWOULDBLOCK)                      \
+                               (RET) = (CONDITION) ? 1 : 0;            \
                        break;                                          \
+               }                                                       \
                const int _dtwu_now = hardclock_ticks;                  \
                KASSERT(_dtwu_start <= _dtwu_now);                      \
                if ((_dtwu_now - _dtwu_start) < _dtwu_ticks) {          \
                        _dtwu_ticks -= (_dtwu_now - _dtwu_start);       \
                } else {                                                \
-                       (RET) = 0;                                      \
+                       (RET) = (CONDITION) ? 1 : 0;                    \
                        break;                                          \
                }                                                       \
        }                                                               \
@@ -210,14 +226,17 @@
                /* XXX errno NetBSD->Linux */                           \
                (RET) = -WAIT((Q), &(INTERLOCK)->sl_lock,               \
                    _dstwu_ticks);                                      \
-               if (RET)                                                \
+               if (RET) {                                              \
+                       if ((RET) == -EWOULDBLOCK)                      \
+                               (RET) = (CONDITION) ? 1 : 0;            \
                        break;                                          \
+               }                                                       \
                const int _dstwu_now = hardclock_ticks;                 \
                KASSERT(_dstwu_start <= _dstwu_now);                    \
                if ((_dstwu_now - _dstwu_start) < _dstwu_ticks) {       \
                        _dstwu_ticks -= (_dstwu_now - _dstwu_start);    \
                } else {                                                \
-                       (RET) = 0;                                      \
+                       (RET) = (CONDITION) ? 1 : 0;                    \
                        break;                                          \
                }                                                       \
        }                                                               \