[PATCH 20/26] idr-test: Convert ida_check_nomem to new API

[Matthew Wilcox]

We can't move this test to kernel space because there's no way to
force kmalloc to fail.  But we can use the new API and check this
works when the test is in userspace.

Signed-off-by: Matthew Wilcox <willy@xxxxxxxxxxxxx>
---
 tools/testing/radix-tree/idr-test.c | 13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/tools/testing/radix-tree/idr-test.c b/tools/testing/radix-tree/idr-test.c
index 604b51dc9b38..0f557784327d 100644
--- a/tools/testing/radix-tree/idr-test.c
+++ b/tools/testing/radix-tree/idr-test.c
@@ -320,19 +320,20 @@ void ida_dump(struct ida *);
 
 /*
  * Check that we get the correct error when we run out of memory doing
- * allocations.  To ensure we run out of memory, just "forget" to preload.
+ * allocations.  In userspace, GFP_NOWAIT will always fail an allocation.
  * The first test is for not having a bitmap available, and the second test
  * is for not being able to allocate a level of the radix tree.
  */
 void ida_check_nomem(void)
 {
 	DEFINE_IDA(ida);
-	int id, err;
+	int id;
 
-	err = ida_get_new_above(&ida, 256, &id);
-	assert(err == -EAGAIN);
-	err = ida_get_new_above(&ida, 1UL << 30, &id);
-	assert(err == -EAGAIN);
+	id = ida_alloc_min(&ida, 256, GFP_NOWAIT);
+	IDA_BUG_ON(&ida, id != -ENOMEM);
+	id = ida_alloc_min(&ida, 1UL << 30, GFP_NOWAIT);
+	IDA_BUG_ON(&ida, id != -ENOMEM);
+	IDA_BUG_ON(&ida, !ida_is_empty(&ida));
 }
 
 /*
-- 
2.17.1