Commit 4e7b8a6c authored Dec 14, 2009 by David Rientjes Committed by Linus Torvalds Dec 15, 2009

nodemask: make NODEMASK_ALLOC more general



This is a series of patches to provide control over the location of the
allocation and freeing of persistent huge pages on a NUMA platform.
Please consider for merging into mmotm.

This series uses two mechanisms to constrain the nodes from which
persistent huge pages are allocated: 1) the task NUMA mempolicy of the
task modifying a new sysctl "nr_hugepages_mempolicy", based on a
suggestion by Mel Gorman; and 2) a subset of the hugepages hstate sysfs
attributes have been added [in V4] to each node system device under:

	/sys/devices/node/node[0-9]*/hugepages

The per node attibutes allow direct assignment of a huge page count on a
specific node, regardless of the task's mempolicy or cpuset constraints.

This patch:

NODEMASK_ALLOC(x, m) assumes x is a type of struct, which is unnecessary.
It's perfectly reasonable to use this macro to allocate a nodemask_t,
which is anonymous, either dynamically or on the stack depending on
NODES_SHIFT.

Signed-off-by: David Rientjes <rientjes@google.com>
Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Nishanth Aravamudan <nacc@us.ibm.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Adam Litke <agl@us.ibm.com>
Cc: Andy Whitcroft <apw@canonical.com>
Cc: Eric Whitney <eric.whitney@hp.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent 6d9c285a

include/linux/nodemask.h

+8 −7

Original line number	Diff line number	Diff line
		@@ -481,14 +481,14 @@ static inline int num_node_state(enum node_states state)

		/*
		* For nodemask scrach area.(See CPUMASK_ALLOC() in cpumask.h)
		* NODEMASK_ALLOC(x, m) allocates an object of type 'x' with the name 'm'.
		*/

		#if NODES_SHIFT > 8 /* nodemask_t > 64 bytes */
		#define NODEMASK_ALLOC(x, m) struct x m = kmalloc(sizeof(m), GFP_KERNEL)
		#define NODEMASK_ALLOC(x, m) 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)
		#define NODEMASK_ALLOC(x, m) x _m, *m = &_m
		#define NODEMASK_FREE(m) do {} while (0)
		#endif

		/* A example struture for using NODEMASK_ALLOC, used in mempolicy. */
		@@ -497,7 +497,8 @@ struct nodemask_scratch {
		nodemask_t mask2;
		};

		#define NODEMASK_SCRATCH(x) NODEMASK_ALLOC(nodemask_scratch, x)
		#define NODEMASK_SCRATCH(x) \
		NODEMASK_ALLOC(struct nodemask_scratch, x)
		#define NODEMASK_SCRATCH_FREE(x) NODEMASK_FREE(x)

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