XArray: Optimise xas_sibling() if !CONFIG_XARRAY_MULTI

If CONFIG_XARRAY_MULTI is disabled, then xas_sibling() must be false.

Reported-by: JaeJoon Jung <rgbi3307@gmail.com>
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>

diff --git a/lib/xarray.c b/lib/xarray.c
index 05324cf..f448bcd 100644 (file)
--- a/lib/xarray.c
+++ b/lib/xarray.c
@@ -1836,7 +1836,7 @@ static bool xas_sibling(struct xa_state *xas)
        struct xa_node *node = xas->xa_node;
        unsigned long mask;
 
-       if (!node)
+       if (!IS_ENABLED(CONFIG_XARRAY_MULTI) || !node)
                return false;
        mask = (XA_CHUNK_SIZE << node->shift) - 1;
        return (xas->xa_index & mask) >