[PATCH v13 48/72] shmem: Convert find_swap_entry to XArray

[Matthew Wilcox]

From: Matthew Wilcox <mawilcox@xxxxxxxxxxxxx>

This is a 1:1 conversion.

Signed-off-by: Matthew Wilcox <mawilcox@xxxxxxxxxxxxx>
---
 mm/shmem.c | 27 ++++++++++-----------------
 1 file changed, 10 insertions(+), 17 deletions(-)

diff --git a/mm/shmem.c b/mm/shmem.c
index 479e4a8e6d68..983a27656e2e 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -1099,34 +1099,27 @@ static void shmem_evict_inode(struct inode *inode)
 	clear_inode(inode);
 }
 
-static unsigned long find_swap_entry(struct radix_tree_root *root, void *item)
+static unsigned long find_swap_entry(struct xarray *xa, void *item)
 {
-	struct radix_tree_iter iter;
-	void __rcu **slot;
-	unsigned long found = -1;
+	XA_STATE(xas, xa, 0);
 	unsigned int checked = 0;
+	void *entry;
 
 	rcu_read_lock();
-	radix_tree_for_each_slot(slot, root, &iter, 0) {
-		void *entry = radix_tree_deref_slot(slot);
-
-		if (radix_tree_deref_retry(entry)) {
-			slot = radix_tree_iter_retry(&iter);
+	xas_for_each(&xas, entry, ULONG_MAX) {
+		if (xas_retry(&xas, entry))
 			continue;
-		}
-		if (entry == item) {
-			found = iter.index;
+		if (entry == item)
 			break;
-		}
 		checked++;
-		if ((checked % 4096) != 0)
+		if ((checked % XA_CHECK_SCHED) != 0)
 			continue;
-		slot = radix_tree_iter_resume(slot, &iter);
+		xas_pause(&xas);
 		cond_resched_rcu();
 	}
-
 	rcu_read_unlock();
-	return found;
+
+	return xas_invalid(&xas) ? -1 : xas.xa_index;
 }
 
 /*
-- 
2.17.1