* to generate slightly worse code. So use a simple one-line #define
* for node_isset(), instead of wrapping an inline inside a macro, the
* way we do the other calls.
+ *
+ * NODEMASK_SCRATCH
+ * When doing above logical AND, OR, XOR, Remap operations the callers tend to
+ * need temporary nodemask_t's on the stack. But if NODES_SHIFT is large,
+ * nodemask_t's consume too much stack space. NODEMASK_SCRATCH is a helper
+ * for such situations. See below and CPUMASK_ALLOC also.
*/
#include <linux/kernel.h>
#define next_online_node(nid) next_node((nid), node_states[N_ONLINE])
extern int nr_node_ids;
+extern int nr_online_nodes;
+
+static inline void node_set_online(int nid)
+{
+ node_set_state(nid, N_ONLINE);
+ nr_online_nodes = num_node_state(N_ONLINE);
+}
+
+static inline void node_set_offline(int nid)
+{
+ node_clear_state(nid, N_ONLINE);
+ nr_online_nodes = num_node_state(N_ONLINE);
+}
#else
static inline int node_state(int node, enum node_states state)
#define first_online_node 0
#define next_online_node(nid) (MAX_NUMNODES)
#define nr_node_ids 1
+#define nr_online_nodes 1
+#define node_set_online(node) node_set_state((node), N_ONLINE)
+#define node_set_offline(node) node_clear_state((node), N_ONLINE)
#endif
#define node_online_map node_states[N_ONLINE]
#define node_online(node) node_state((node), N_ONLINE)
#define node_possible(node) node_state((node), N_POSSIBLE)
-#define node_set_online(node) node_set_state((node), N_ONLINE)
-#define node_set_offline(node) node_clear_state((node), N_ONLINE)
-
#define for_each_node(node) for_each_node_state(node, N_POSSIBLE)
#define for_each_online_node(node) for_each_node_state(node, N_ONLINE)
+/*
+ * For nodemask scrach area.(See CPUMASK_ALLOC() in cpumask.h)
+ */
+
+#if NODES_SHIFT > 8 /* nodemask_t > 64 bytes */
+#define NODEMASK_ALLOC(x, m) struct x *m = kmalloc(sizeof(*m), GFP_KERNEL)
+#define NODEMASK_FREE(m) kfree(m)
+#else
+#define NODEMASK_ALLOC(x, m) struct x _m, *m = &_m
+#define NODEMASK_FREE(m)
+#endif
+
+/* A example struture for using NODEMASK_ALLOC, used in mempolicy. */
+struct nodemask_scratch {
+ nodemask_t mask1;
+ nodemask_t mask2;
+};
+
+#define NODEMASK_SCRATCH(x) NODEMASK_ALLOC(nodemask_scratch, x)
+#define NODEMASK_SCRATCH_FREE(x) NODEMASK_FREE(x)
+
+
#endif /* __LINUX_NODEMASK_H */