From e13fe8695c57fed678877a9f3f8e99fc637ff4fb Mon Sep 17 00:00:00 2001
From: Wen Congyang <wency@cn.fujitsu.com>
Date: Fri, 22 Feb 2013 16:33:31 -0800
Subject: [PATCH] cpu-hotplug,memory-hotplug: clear cpu_to_node() when
offlining the node
When the node is offlined, there is no memory/cpu on the node. If a
sleep task runs on a cpu of this node, it will be migrated to the cpu on
the other node. So we can clear cpu-to-node mapping.
[akpm@linux-foundation.org: numa_clear_node() and numa_set_node() can no longer be __cpuinit]
Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Jiang Liu <liuj97@gmail.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
arch/x86/include/asm/numa.h | 4 ++--
arch/x86/mm/numa.c | 4 ++--
mm/memory_hotplug.c | 30 +++++++++++++++++++++++++++++-
3 files changed, 33 insertions(+), 5 deletions(-)
diff --git a/arch/x86/include/asm/numa.h b/arch/x86/include/asm/numa.h
index 52560a2038e10..1b99ee5c9f00d 100644
--- a/arch/x86/include/asm/numa.h
+++ b/arch/x86/include/asm/numa.h
@@ -57,8 +57,8 @@ static inline int numa_cpu_node(int cpu)
#endif
#ifdef CONFIG_NUMA
-extern void __cpuinit numa_set_node(int cpu, int node);
-extern void __cpuinit numa_clear_node(int cpu);
+extern void numa_set_node(int cpu, int node);
+extern void numa_clear_node(int cpu);
extern void __init init_cpu_to_node(void);
extern void __cpuinit numa_add_cpu(int cpu);
extern void __cpuinit numa_remove_cpu(int cpu);
diff --git a/arch/x86/mm/numa.c b/arch/x86/mm/numa.c
index f22680bf69ece..a713d081b59cd 100644
--- a/arch/x86/mm/numa.c
+++ b/arch/x86/mm/numa.c
@@ -78,7 +78,7 @@ EXPORT_SYMBOL(node_to_cpumask_map);
DEFINE_EARLY_PER_CPU(int, x86_cpu_to_node_map, NUMA_NO_NODE);
EXPORT_EARLY_PER_CPU_SYMBOL(x86_cpu_to_node_map);
-void __cpuinit numa_set_node(int cpu, int node)
+void numa_set_node(int cpu, int node)
{
int *cpu_to_node_map = early_per_cpu_ptr(x86_cpu_to_node_map);
@@ -101,7 +101,7 @@ void __cpuinit numa_set_node(int cpu, int node)
set_cpu_numa_node(cpu, node);
}
-void __cpuinit numa_clear_node(int cpu)
+void numa_clear_node(int cpu)
{
numa_set_node(cpu, NUMA_NO_NODE);
}
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index 17e1447077ab7..a9072a16a1601 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -1705,6 +1705,34 @@ static int check_cpu_on_node(void *data)
return 0;
}
+static void unmap_cpu_on_node(void *data)
+{
+#ifdef CONFIG_ACPI_NUMA
+ struct pglist_data *pgdat = data;
+ int cpu;
+
+ for_each_possible_cpu(cpu)
+ if (cpu_to_node(cpu) == pgdat->node_id)
+ numa_clear_node(cpu);
+#endif
+}
+
+static int check_and_unmap_cpu_on_node(void *data)
+{
+ int ret = check_cpu_on_node(data);
+
+ if (ret)
+ return ret;
+
+ /*
+ * the node will be offlined when we come here, so we can clear
+ * the cpu_to_node() now.
+ */
+
+ unmap_cpu_on_node(data);
+ return 0;
+}
+
/* offline the node if all memory sections of this node are removed */
void try_offline_node(int nid)
{
@@ -1731,7 +1759,7 @@ void try_offline_node(int nid)
return;
}
- if (stop_machine(check_cpu_on_node, pgdat, NULL))
+ if (stop_machine(check_and_unmap_cpu_on_node, pgdat, NULL))
return;
/*
--
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