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-rwxr-xr-xscripts/atomic/fallbacks/dec_unless_positive14
1 files changed, 14 insertions, 0 deletions
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