4 files changed, 51 insertions, 0 deletions
diff --git a/scripts/atomic/fallbacks/dec b/scripts/atomic/fallbacks/dec
new file mode 100755
index 000000000..e2e01f057
--- /dev/null
+++ b/scripts/atomic/fallbacks/dec
@@ -0,0 +1,7 @@
+cat <<EOF
+static __always_inline ${ret}
+${arch}${atomic}_${pfx}dec${sfx}${order}(${atomic}_t *v)
+{
+	${retstmt}${arch}${atomic}_${pfx}sub${sfx}${order}(1, v);
+}
+EOF
diff --git a/scripts/atomic/fallbacks/dec_and_test b/scripts/atomic/fallbacks/dec_and_test
new file mode 100755
index 000000000..e8a5e492e
--- /dev/null
+++ b/scripts/atomic/fallbacks/dec_and_test
@@ -0,0 +1,15 @@
+cat <<EOF
+/**
+ * ${arch}${atomic}_dec_and_test - decrement and test
+ * @v: pointer of type ${atomic}_t
+ *
+ * Atomically decrements @v by 1 and
+ * returns true if the result is 0, or false for all other
+ * cases.
+ */
+static __always_inline bool
+${arch}${atomic}_dec_and_test(${atomic}_t *v)
+{
+	return ${arch}${atomic}_dec_return(v) == 0;
+}
+EOF
diff --git a/scripts/atomic/fallbacks/dec_if_positive b/scripts/atomic/fallbacks/dec_if_positive
new file mode 100755
index 000000000..527adec89
--- /dev/null
+++ b/scripts/atomic/fallbacks/dec_if_positive
@@ -0,0 +1,15 @@
+cat <<EOF
+static __always_inline ${ret}
+${arch}${atomic}_dec_if_positive(${atomic}_t *v)
+{
+	${int} dec, c = ${arch}${atomic}_read(v);
+
+	do {
+		dec = c - 1;
+		if (unlikely(dec < 0))
+			break;
+	} while (!${arch}${atomic}_try_cmpxchg(v, &c, dec));
+
+	return dec;
+}
+EOF
diff --git a/scripts/atomic/fallbacks/dec_unless_positive b/scripts/atomic/fallbacks/dec_unless_positive
new file mode 100755
index 000000000..dcab6848c
--- /dev/null
+++ b/scripts/atomic/fallbacks/dec_unless_positive
@@ -0,0 +1,14 @@
+cat <<EOF
+static __always_inline bool
+${arch}${atomic}_dec_unless_positive(${atomic}_t *v)
+{
+	${int} c = ${arch}${atomic}_read(v);
+
+	do {
+		if (unlikely(c > 0))
+			return false;
+	} while (!${arch}${atomic}_try_cmpxchg(v, &c, c - 1));
+
+	return true;
+}
+EOF