1 files changed, 53 insertions, 0 deletions

diff --git a/include/litmus/dgl.h b/include/litmus/dgl.h
new file mode 100644
index 000000000000..989f6c7d5e8e
--- /dev/null
+++ b/include/litmus/dgl.h
@@ -0,0 +1,53 @@
+#ifndef __DGL_H_
+#define __DGL_H_
+
+#include <linux/list.h>
+
+#define NUM_REPLICAS  4
+#define NUM_RESOURCES 4
+#define MASK_SIZE     (sizeof(unsigned long) * 8)
+#define MASK_WORDS    (NUM_RESOURCES/MASK_SIZE + (NUM_RESOURCES%MASK_SIZE != 0))
+
+/*
+ * A request for @replica amount of a single resource.
+ */
+struct dgl_req {
+        unsigned short          replicas;
+        struct list_head        list;
+};
+
+/*
+ * Simultaneous @requests for multiple resources.
+ */
+struct dgl_group_req {
+        int                     cpu;
+        unsigned long           requested[MASK_WORDS];
+        unsigned long           waiting[MASK_WORDS];
+        struct dgl_req          requests[NUM_RESOURCES];
+};
+
+/*
+ * A single resource.
+ */
+struct dgl_resource {
+        unsigned int            free_replicas;
+        struct list_head        waiting;
+};
+
+/*
+ * A group of resources.
+ */
+struct dgl {
+        struct dgl_resource     resources[NUM_RESOURCES];
+        struct dgl_group_req*   acquired[NR_CPUS];
+};
+
+void dgl_init(struct dgl *dgl);
+void dgl_group_req_init(struct dgl_group_req *greq);
+
+void set_req(struct dgl_group_req *greq, int resource, int replicas);
+
+void add_group_req(struct dgl *dgl, struct dgl_group_req *greq, int cpu);
+void remove_group_req(struct dgl *dgl, struct dgl_group_req *greq);
+
+#endif