radix tree test suite: Add kmem_cache_set_non_kernel()

kmem_cache_set_non_kernel() is a mechanism to allow a certain number of
kmem_cache_alloc requests to succeed even when GFP_KERNEL is not set in
the flags.  This functionality allows for testing different paths though
the code.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Liam R. Howlett <Liam.Howlett@Oracle.com>

diff --git a/tools/testing/radix-tree/linux.c b/tools/testing/radix-tree/linux.c
index 2d9c59df60de03be87fc92a5482b7c3eb17a4463..00ee01a146526b42528513885ebda063d2e3f59c 100644 (file)
--- a/tools/testing/radix-tree/linux.c
+++ b/tools/testing/radix-tree/linux.c
@@ -24,14 +24,24 @@ struct kmem_cache {
        int nr_objs;
        void *objs;
        void (*ctor)(void *);
+       unsigned int non_kernel;
 };
 
+void kmem_cache_set_non_kernel(struct kmem_cache *cachep, unsigned int val)
+{
+       cachep->non_kernel = val;
+}
+
 void *kmem_cache_alloc(struct kmem_cache *cachep, int gfp)
 {
        void *p;
 
-       if (!(gfp & __GFP_DIRECT_RECLAIM))
-               return NULL;
+       if (!(gfp & __GFP_DIRECT_RECLAIM)) {
+               if (!cachep->non_kernel)
+                       return NULL;
+
+               cachep->non_kernel--;
+       }
 
        pthread_mutex_lock(&cachep->lock);
        if (cachep->nr_objs) {
@@ -116,5 +126,6 @@ kmem_cache_create(const char *name, unsigned int size, unsigned int align,
        ret->nr_objs = 0;
        ret->objs = NULL;
        ret->ctor = ctor;
+       ret->non_kernel = 0;
        return ret;
 }