[PATCH 4/6] hugetlb: introduce alloc_nodemask_of_node

Lee Schermerhorn
2009-08-28T16:03:38Z

[PATCH 4/6] - hugetlb: introduce alloc_nodemask_of_node()

Against: 2.6.31-rc7-mmotm-090827-0057

New in V5 of series

Introduce nodemask macro to allocate a nodemask and
initialize it to contain a single node, using the macro
init_nodemask_of_node() factored out of the nodemask_of_node()
macro.

alloc_nodemask_of_node() coded as a macro to avoid header
dependency hell.

This will be used to construct the huge pages "nodes_allowed"
nodemask for a single node when a persistent huge page
pool page count is modified via a per node sysfs attribute.

Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com>

include/linux/nodemask.h | 20 ++++++++++++++++++--
1 file changed, 18 insertions(+), 2 deletions(-)

Index: linux-2.6.31-rc7-mmotm-090827-0057/include/linux/nodemask.h
===================================================================
--- linux-2.6.31-rc7-mmotm-090827-0057.orig/include/linux/nodemask.h 2009-08-28 09:21:19.000000000 -0400
+++ linux-2.6.31-rc7-mmotm-090827-0057/include/linux/nodemask.h 2009-08-28 09:21:29.000000000 -0400
@@ -245,18 +245,34 @@ static inline int __next_node(int n, con
return min_t(int,MAX_NUMNODES,find_next_bit(srcp->bits, MAX_NUMNODES, n+1));
}

+#define init_nodemask_of_nodes(mask, node) \
+ nodes_clear(*(mask)); \
+ node_set((node), *(mask));
+
#define nodemask_of_node(node) \
({ \
typeof(_unused_nodemask_arg_) m; \
if (sizeof(m) == sizeof(unsigned long)) { \
m.bits[0] = 1UL<<(node); \
} else { \
- nodes_clear(m); \
- node_set((node), m); \
+ init_nodemask_of_nodes(&m, (node)); \
} \
m; \
})

+/*
+ * returns pointer to kmalloc()'d nodemask initialized to contain the
+ * specified node. Caller must free with kfree().
+ */
+#define alloc_nodemask_of_node(node) \
+({ \
+ typeof(_unused_nodemask_arg_) *nmp; \
+ nmp = kmalloc(sizeof(*nmp), GFP_KERNEL); \
+ if (nmp) \
+ init_nodemask_of_nodes(nmp, (node)); \
+ nmp; \
+})
+
#define first_unset_node(mask) __first_unset_node(&(mask))
static inline int __first_unset_node(const nodemask_t *maskp)
{