diff options
author | Lee Schermerhorn <lee.schermerhorn@hp.com> | 2010-05-26 14:44:56 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2010-05-27 09:12:57 -0700 |
commit | 7281201922a0063fa60804ce39c277fc98142a47 (patch) | |
tree | 4bf089d077b1055e54bc1411dcc0db121d01d9fa /include/linux/topology.h | |
parent | 866707fc2721df8fee637fcf0239628b9231f9ea (diff) |
numa: add generic percpu var numa_node_id() implementation
Rework the generic version of the numa_node_id() function to use the new
generic percpu variable infrastructure.
Guard the new implementation with a new config option:
CONFIG_USE_PERCPU_NUMA_NODE_ID.
Archs which support this new implemention will default this option to 'y'
when NUMA is configured. This config option could be removed if/when all
archs switch over to the generic percpu implementation of numa_node_id().
Arch support involves:
1) converting any existing per cpu variable implementations to use
this implementation. x86_64 is an instance of such an arch.
2) archs that don't use a per cpu variable for numa_node_id() will
need to initialize the new per cpu variable "numa_node" as cpus
are brought on-line. ia64 is an example.
3) Defining USE_PERCPU_NUMA_NODE_ID in arch dependent Kconfig--e.g.,
when NUMA is configured. This is required because I have
retained the old implementation by default to allow archs to
be modified incrementally, as desired.
Subsequent patches will convert x86_64 and ia64 to use this implemenation.
Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Mel Gorman <mel@csn.ul.ie>
Reviewed-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Nick Piggin <npiggin@suse.de>
Cc: David Rientjes <rientjes@google.com>
Cc: Eric Whitney <eric.whitney@hp.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'include/linux/topology.h')
-rw-r--r-- | include/linux/topology.h | 51 |
1 files changed, 46 insertions, 5 deletions
diff --git a/include/linux/topology.h b/include/linux/topology.h index 5b81156780b1..2e5518f46571 100644 --- a/include/linux/topology.h +++ b/include/linux/topology.h @@ -31,6 +31,7 @@ #include <linux/bitops.h> #include <linux/mmzone.h> #include <linux/smp.h> +#include <linux/percpu.h> #include <asm/topology.h> #ifndef node_has_online_mem @@ -203,8 +204,53 @@ int arch_update_cpu_topology(void); #ifndef SD_NODE_INIT #error Please define an appropriate SD_NODE_INIT in include/asm/topology.h!!! #endif + #endif /* CONFIG_NUMA */ +#ifdef CONFIG_USE_PERCPU_NUMA_NODE_ID +DECLARE_PER_CPU(int, numa_node); + +#ifndef numa_node_id +/* Returns the number of the current Node. */ +static inline int numa_node_id(void) +{ + return __this_cpu_read(numa_node); +} +#endif + +#ifndef cpu_to_node +static inline int cpu_to_node(int cpu) +{ + return per_cpu(numa_node, cpu); +} +#endif + +#ifndef set_numa_node +static inline void set_numa_node(int node) +{ + percpu_write(numa_node, node); +} +#endif + +#ifndef set_cpu_numa_node +static inline void set_cpu_numa_node(int cpu, int node) +{ + per_cpu(numa_node, cpu) = node; +} +#endif + +#else /* !CONFIG_USE_PERCPU_NUMA_NODE_ID */ + +/* Returns the number of the current Node. */ +#ifndef numa_node_id +static inline int numa_node_id(void) +{ + return cpu_to_node(raw_smp_processor_id()); +} +#endif + +#endif /* [!]CONFIG_USE_PERCPU_NUMA_NODE_ID */ + #ifndef topology_physical_package_id #define topology_physical_package_id(cpu) ((void)(cpu), -1) #endif @@ -218,9 +264,4 @@ int arch_update_cpu_topology(void); #define topology_core_cpumask(cpu) cpumask_of(cpu) #endif -/* Returns the number of the current Node. */ -#ifndef numa_node_id -#define numa_node_id() (cpu_to_node(raw_smp_processor_id())) -#endif - #endif /* _LINUX_TOPOLOGY_H */ |