linux/include/asm-generic/topology.h
Mike Travis aa6b54461c asm-generic: add node_to_cpumask_ptr macro
Create a simple macro to always return a pointer to the node_to_cpumask(node)
value.  This relies on compiler optimization to remove the extra indirection:

    #define node_to_cpumask_ptr(v, node) 		\
	    cpumask_t _##v = node_to_cpumask(node), *v = &_##v

For those systems with a large cpumask size, then a true pointer
to the array element can be used:

    #define node_to_cpumask_ptr(v, node)		\
	    cpumask_t *v = &(node_to_cpumask_map[node])

A node_to_cpumask_ptr_next() macro is provided to access another
node_to_cpumask value.

The other change is to always include asm-generic/topology.h moving the
ifdef CONFIG_NUMA to this same file.

Note: there are no references to either of these new macros in this patch,
only the definition.

Based on 2.6.25-rc5-mm1

# alpha
Cc: Richard Henderson <rth@twiddle.net>

# fujitsu
Cc: David Howells <dhowells@redhat.com>

# ia64
Cc: Tony Luck <tony.luck@intel.com>

# powerpc
Cc: Paul Mackerras <paulus@samba.org>
Cc: Anton Blanchard <anton@samba.org>

# sparc
Cc: David S. Miller <davem@davemloft.net>
Cc: William L. Irwin <wli@holomorphy.com>

# x86
Cc: H. Peter Anvin <hpa@zytor.com>

Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-19 19:44:58 +02:00

70 lines
2.0 KiB
C

/*
* linux/include/asm-generic/topology.h
*
* Written by: Matthew Dobson, IBM Corporation
*
* Copyright (C) 2002, IBM Corp.
*
* All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
* NON INFRINGEMENT. See the GNU General Public License for more
* details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*
* Send feedback to <colpatch@us.ibm.com>
*/
#ifndef _ASM_GENERIC_TOPOLOGY_H
#define _ASM_GENERIC_TOPOLOGY_H
#ifndef CONFIG_NUMA
/* Other architectures wishing to use this simple topology API should fill
in the below functions as appropriate in their own <asm/topology.h> file. */
#ifndef cpu_to_node
#define cpu_to_node(cpu) ((void)(cpu),0)
#endif
#ifndef parent_node
#define parent_node(node) ((void)(node),0)
#endif
#ifndef node_to_cpumask
#define node_to_cpumask(node) ((void)node, cpu_online_map)
#endif
#ifndef node_to_first_cpu
#define node_to_first_cpu(node) ((void)(node),0)
#endif
#ifndef pcibus_to_node
#define pcibus_to_node(bus) ((void)(bus), -1)
#endif
#ifndef pcibus_to_cpumask
#define pcibus_to_cpumask(bus) (pcibus_to_node(bus) == -1 ? \
CPU_MASK_ALL : \
node_to_cpumask(pcibus_to_node(bus)) \
)
#endif
#endif /* CONFIG_NUMA */
/* returns pointer to cpumask for specified node */
#ifndef node_to_cpumask_ptr
#define node_to_cpumask_ptr(v, node) \
cpumask_t _##v = node_to_cpumask(node), *v = &_##v
#define node_to_cpumask_ptr_next(v, node) \
_##v = node_to_cpumask(node)
#endif
#endif /* _ASM_GENERIC_TOPOLOGY_H */