[PATCH] [3/4] SLAB: Set up the l3 lists for the memory of freshly added memory v2

Andi Kleen
2010-02-11T20:54:08Z

So kmalloc_node() works even if no CPU is up yet on the new node.

v2: Take cache chain mutex

Signed-off-by: Andi Kleen <ak@linux.intel.com>

---
mm/slab.c | 20 ++++++++++++++++++++
1 file changed, 20 insertions(+)

Index: linux-2.6.32-memhotadd/mm/slab.c
===================================================================
--- linux-2.6.32-memhotadd.orig/mm/slab.c
+++ linux-2.6.32-memhotadd/mm/slab.c
@@ -115,6 +115,7 @@
#include <linux/reciprocal_div.h>
#include <linux/debugobjects.h>
#include <linux/kmemcheck.h>
+#include <linux/memory.h>

#include <asm/cacheflush.h>
#include <asm/tlbflush.h>
@@ -1554,6 +1555,23 @@ void __init kmem_cache_init(void)
g_cpucache_up = EARLY;
}

+static int slab_memory_callback(struct notifier_block *self,
+ unsigned long action, void *arg)
+{
+ struct memory_notify *mn = (struct memory_notify *)arg;
+
+ /*
+ * When a node goes online allocate l3s early. This way
+ * kmalloc_node() works for it.
+ */
+ if (action == MEM_ONLINE && mn->status_change_nid >= 0) {
+ mutex_lock(&cache_chain_mutex);
+ slab_node_prepare(mn->status_change_nid);
+ mutex_unlock(&cache_chain_mutex);
+ }
+ return NOTIFY_OK;
+}
+
void __init kmem_cache_init_late(void)
{
struct kmem_cache *cachep;
@@ -1577,6 +1595,8 @@ void __init kmem_cache_init_late(void)
*/
register_cpu_notifier(&cpucache_notifier);

+ hotplug_memory_notifier(slab_memory_callback, SLAB_CALLBACK_PRI);
+
/*
* The reap timers are started later, with a module init call: That part
* of the kernel is not yet operational.