Author: marcel
Date: Wed Jan 1 22:51:19 2014
New Revision: 260175
URL: http://svnweb.freebsd.org/changeset/base/260175
Log:
Implement atomic_swap_<type>.
The operation was documented and implemented partially (both from a
type and architecture perspective) on 2013-08-21 and got used in
ZFS with revision 260150 (zfeature.c) and since ZFS is supported on
ia64, the lack of having atomic_swap became problem.
Modified:
head/sys/ia64/include/atomic.h
Modified: head/sys/ia64/include/atomic.h
==============================================================================
--- head/sys/ia64/include/atomic.h Wed Jan 1 22:49:37 2014
(r260174)
+++ head/sys/ia64/include/atomic.h Wed Jan 1 22:51:19 2014
(r260175)
@@ -386,4 +386,32 @@ atomic_fetchadd_long(volatile u_long *p,
return (value);
}
+/*
+ * <type> atomic_swap_<type>(volatile <type> *p, <type> v);
+ */
+
+static __inline uint32_t
+atomic_swap_32(volatile uint32_t *p, uint32_t v)
+{
+ uint32_t r;
+
+ __asm __volatile ("xchg4 %0 = %3, %2;;" : "=r"(r), "=m"(*p) :
+ "r"(v), "m"(*p) : "memory");
+ return (r);
+}
+
+static __inline uint64_t
+atomic_swap_64(volatile uint64_t *p, uint64_t v)
+{
+ uint64_t r;
+
+ __asm __volatile ("xchg8 %0 = %3, %2;;" : "=r"(r), "=m"(*p) :
+ "r"(v), "m"(*p) : "memory");
+ return (r);
+}
+
+#define atomic_swap_int atomic_swap_32
+#define atomic_swap_long atomic_swap_64
+#define atomic_swap_ptr atomic_swap_64
+
#endif /* ! _MACHINE_ATOMIC_H_ */
_______________________________________________
svn-src-head@freebsd.org mailing list
http://lists.freebsd.org/mailman/listinfo/svn-src-head
To unsubscribe, send any mail to "svn-src-head-unsubscr...@freebsd.org"
