From: jsg <jsg@openbsd.org>
Date: Tue, 30 Jan 2018 08:15:17 +0000 (+0000)
Subject: add atomic_cmpxchg()/atomic64_add()/atomic64_sub()
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=2cba1eeba975ba1d76f9fd969aefeee45d3bfb81;p=openbsd

add atomic_cmpxchg()/atomic64_add()/atomic64_sub()
---

diff --git a/sys/dev/pci/drm/drm_linux_atomic.h b/sys/dev/pci/drm/drm_linux_atomic.h
index 8f23b37b2f6..a82e95d1936 100644
--- a/sys/dev/pci/drm/drm_linux_atomic.h
+++ b/sys/dev/pci/drm/drm_linux_atomic.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: drm_linux_atomic.h,v 1.1 2017/07/01 16:14:10 kettenis Exp $ */
+/* $OpenBSD: drm_linux_atomic.h,v 1.2 2018/01/30 08:15:17 jsg Exp $ */
 /**
  * \file drm_atomic.h
  * Atomic operations used in the DRM which may or may not be provided by the OS.
@@ -50,6 +50,7 @@ typedef uint32_t atomic_t;
 #define atomic_dec_and_test(v)	(atomic_dec_return(v) == 0)
 #define atomic_inc_and_test(v)	(atomic_inc_return(v) == 0)
 #define atomic_or(n, p)		atomic_setbits_int(p, n)
+#define atomic_cmpxchg(p, o, n)	__sync_val_compare_and_swap(p, o, n)
 
 static __inline int
 atomic_xchg(volatile int *v, int n)
@@ -87,6 +88,9 @@ atomic64_xchg(volatile int64_t *v, int64_t n)
 	return __sync_lock_test_and_set(v, n);
 }
 
+#define atomic64_add(n, p)	__sync_fetch_and_add_8(p, n)
+#define atomic64_sub(n, p)	__sync_fetch_and_sub_8(p, n)
+
 #else
 
 typedef struct {
@@ -125,6 +129,22 @@ atomic64_xchg(atomic64_t *v, int64_t n)
 
 	return val;
 }
+
+static __inline void
+atomic64_add(int i, atomic64_t *v)
+{
+	mtx_enter(&v->lock);
+	v->val += i;
+	mtx_leave(&v->lock);
+}
+
+static __inline void
+atomic64_sub(int i, atomic64_t *v)
+{
+	mtx_enter(&v->lock);
+	v->val -= i;
+	mtx_leave(&v->lock);
+}
 #endif
 
 static inline int