atomic: update documentation

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

1 files changed, 12 insertions, 1 deletions

diff --git a/docs/devel/atomics.txt b/docs/devel/atomics.txt
index 3ef5d85b1b..048e5f23cb 100644
--- a/docs/devel/atomics.txt
+++ b/docs/devel/atomics.txt
@@ -63,11 +63,22 @@ operations:
     typeof(*ptr) atomic_fetch_sub(ptr, val)
     typeof(*ptr) atomic_fetch_and(ptr, val)
     typeof(*ptr) atomic_fetch_or(ptr, val)
+    typeof(*ptr) atomic_fetch_xor(ptr, val)
     typeof(*ptr) atomic_xchg(ptr, val)
     typeof(*ptr) atomic_cmpxchg(ptr, old, new)
 
 all of which return the old value of *ptr.  These operations are
-polymorphic; they operate on any type that is as wide as an int.
+polymorphic; they operate on any type that is as wide as a pointer.
+
+Similar operations return the new value of *ptr:
+
+    typeof(*ptr) atomic_inc_fetch(ptr)
+    typeof(*ptr) atomic_dec_fetch(ptr)
+    typeof(*ptr) atomic_add_fetch(ptr, val)
+    typeof(*ptr) atomic_sub_fetch(ptr, val)
+    typeof(*ptr) atomic_and_fetch(ptr, val)
+    typeof(*ptr) atomic_or_fetch(ptr, val)
+    typeof(*ptr) atomic_xor_fetch(ptr, val)
 
 Sequentially consistent loads and stores can be done using: