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

David Rientjes
2010-02-11T21:45:23Z

On Thu, 11 Feb 2010, Andi Kleen wrote:

> 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);
> +

Only needed for CONFIG_NUMA, but there's no side-effects for UMA kernels
since status_change_nid will always be -1.

Acked-by: David Rientjes <rientjes@google.com>