Module Name: src
Committed By: riastradh
Date: Mon Aug 27 13:58:16 UTC 2018
Modified Files:
src/sys/external/bsd/drm2/include/linux: atomic.h
Log Message:
Add atomic_long.
To generate a diff of this commit:
cvs rdiff -u -r1.13 -r1.14 src/sys/external/bsd/drm2/include/linux/atomic.h
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/external/bsd/drm2/include/linux/atomic.h
diff -u src/sys/external/bsd/drm2/include/linux/atomic.h:1.13 src/sys/external/bsd/drm2/include/linux/atomic.h:1.14
--- src/sys/external/bsd/drm2/include/linux/atomic.h:1.13 Mon Aug 27 13:41:08 2018
+++ src/sys/external/bsd/drm2/include/linux/atomic.h Mon Aug 27 13:58:16 2018
@@ -1,4 +1,4 @@
-/* $NetBSD: atomic.h,v 1.13 2018/08/27 13:41:08 riastradh Exp $ */
+/* $NetBSD: atomic.h,v 1.14 2018/08/27 13:58:16 riastradh Exp $ */
/*-
* Copyright (c) 2013 The NetBSD Foundation, Inc.
@@ -286,6 +286,68 @@ atomic64_cmpxchg(struct atomic64 *atomic
return old;
}
+struct atomic_long {
+ volatile unsigned long al_v;
+};
+
+typedef struct atomic_long atomic_long_t;
+
+static inline long
+atomic_long_read(struct atomic_long *a)
+{
+ /* no membar */
+ return (unsigned long)a->al_v;
+}
+
+static inline void
+atomic_long_set(struct atomic_long *a, long v)
+{
+ /* no membar */
+ a->al_v = v;
+}
+
+static inline long
+atomic_long_add_unless(struct atomic_long *a, long addend, long zero)
+{
+ long value;
+
+ smp_mb__before_atomic();
+ do {
+ value = (long)a->al_v;
+ if (value == zero)
+ break;
+ } while (atomic_cas_ulong(&a->al_v, (unsigned long)value,
+ (unsigned long)(value + addend)) != (unsigned long)value);
+ smp_mb__after_atomic();
+
+ return value != zero;
+}
+
+static inline long
+atomic_long_inc_not_zero(struct atomic_long *a)
+{
+ /* membar implied by atomic_long_add_unless */
+ return atomic_long_add_unless(a, 1, 0);
+}
+
+static inline long
+atomic_long_cmpxchg(struct atomic_long *a, long expect, long new)
+{
+ long old;
+
+ /*
+ * XXX As an optimization, under Linux's semantics we are
+ * allowed to skip the memory barrier if the comparison fails,
+ * but taking advantage of that is not convenient here.
+ */
+ smp_mb__before_atomic();
+ old = (long)atomic_cas_ulong(&a->al_v, (unsigned long)expect,
+ (unsigned long)new);
+ smp_mb__after_atomic();
+
+ return old;
+}
+
static inline void
set_bit(unsigned int bit, volatile unsigned long *ptr)
{
