From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Tue, 02 Oct 2007 11:20:43 +0900 From: Yasunori Goto Subject: Re: [Patch / 002](memory hotplug) Callback function to create kmem_cache_node. In-Reply-To: References: <20071001183316.7A9B.Y-GOTO@jp.fujitsu.com> Message-Id: <20071002105422.2790.Y-GOTO@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Christoph Lameter Cc: Andrew Morton , Linux Kernel ML , linux-mm List-ID: > On Mon, 1 Oct 2007, Yasunori Goto wrote: > > > +#ifdef CONFIG_MEMORY_HOTPLUG > > +static void __slab_callback_offline(int nid) > > +{ > > + struct kmem_cache_node *n; > > + struct kmem_cache *s; > > + > > + list_for_each_entry(s, &slab_caches, list) { > > + if (s->node[nid]) { > > + n = get_node(s, nid); > > + s->node[nid] = NULL; > > + kmem_cache_free(kmalloc_caches, n); > > + } > > + } > > +} > > I think we need to bug here if there are still objects on the node that > are in use. This will silently discard the objects. > Here is just the rollback code for an allocation failure of kmem_cache_node in halfway. So, there is a case some of them are not allocated yet. Any slabs don't use new kmem_cache_node before the new nodes page is available --so far--. But, in the future, here will be useful for node hot-unplug code, and its check will be necessary. Ok. I'll add its check. Do you mean that just nr_slabs should be checked like followings? I'm not sure this is enough. : if (s->node[nid]) { n = get_node(s, nid); if (!atomic_read(&n->nr_slabs)) { s->node[nid] = NULL; kmem_cache_free(kmalloc_caches, n); } } : : Thanks. -- Yasunori Goto -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org