We have test_and_set_bit but not test_and_clear_bit. Add it.
Signed-off-by: Peter Xu <peterx@xxxxxxxxxx>
---
tools/include/linux/bitmap.h | 17 +++++++++++++++++
1 file changed, 17 insertions(+)
diff --git a/tools/include/linux/bitmap.h b/tools/include/linux/bitmap.h
index 63440cc8d618..e63662db131b 100644
--- a/tools/include/linux/bitmap.h
+++ b/tools/include/linux/bitmap.h
@@ -96,6 +96,23 @@ static inline int test_and_set_bit(int nr, unsigned long *addr)
return (old & mask) != 0;
}
+/**
+ * test_and_clear_bit - Clear a bit and return its old value
+ * @nr: Bit to clear
+ * @addr: Address to count from
+ */
+static inline int test_and_clear_bit(int nr, unsigned long *addr)
+{
+ unsigned long mask = BIT_MASK(nr);
+ unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
+ unsigned long old;
+
+ old = *p;
+ *p = old & ~mask;
+
+ return (old & mask) != 0;
+}
+
/**
* bitmap_alloc - Allocate bitmap
* @nbits: Number of bits
--
2.17.1
