linux/arch/x86/include/asm/numa.h
Tejun Heo bbc9e2f452 x86: Unify cpu/apicid <-> NUMA node mapping between 32 and 64bit
The mapping between cpu/apicid and node is done via
apicid_to_node[] on 64bit and apicid_2_node[] +
apic->x86_32_numa_cpu_node() on 32bit. This difference makes it
difficult to further unify 32 and 64bit NUMA handling.

This patch unifies it by replacing both apicid_to_node[] and
apicid_2_node[] with __apicid_to_node[] array, which is accessed
by two accessors - set_apicid_to_node() and numa_cpu_node().  On
64bit, numa_cpu_node() always consults __apicid_to_node[]
directly while 32bit goes through apic->numa_cpu_node() method
to allow apic implementations to override it.

srat_detect_node() for amd cpus contains workaround for broken
NUMA configuration which assumes relationship between APIC ID,
HT node ID and NUMA topology.  Leave it to access
__apicid_to_node[] directly as mapping through CPU might result
in undesirable behavior change.  The comment is reformatted and
updated to note the ugliness.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Pekka Enberg <penberg@kernel.org>
Cc: eric.dumazet@gmail.com
Cc: yinghai@kernel.org
Cc: brgerst@gmail.com
Cc: gorcunov@gmail.com
Cc: shaohui.zheng@intel.com
Cc: rientjes@google.com
LKML-Reference: <1295789862-25482-14-git-send-email-tj@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: David Rientjes <rientjes@google.com>
2011-01-28 14:54:09 +01:00

34 lines
760 B
C

#ifndef _ASM_X86_NUMA_H
#define _ASM_X86_NUMA_H
#include <asm/apicdef.h>
#ifdef CONFIG_NUMA
/*
* __apicid_to_node[] stores the raw mapping between physical apicid and
* node and is used to initialize cpu_to_node mapping.
*
* The mapping may be overridden by apic->numa_cpu_node() on 32bit and thus
* should be accessed by the accessors - set_apicid_to_node() and
* numa_cpu_node().
*/
extern s16 __apicid_to_node[MAX_LOCAL_APIC];
static inline void set_apicid_to_node(int apicid, s16 node)
{
__apicid_to_node[apicid] = node;
}
#else /* CONFIG_NUMA */
static inline void set_apicid_to_node(int apicid, s16 node)
{
}
#endif /* CONFIG_NUMA */
#ifdef CONFIG_X86_32
# include "numa_32.h"
#else
# include "numa_64.h"
#endif
#endif /* _ASM_X86_NUMA_H */