Merge branch 'slub/hotplug' into slab/urgent

diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h
index 24376fe7ee68b5cc71cca000cfdc260527de207b..8122018d300029167518eb4a9c93e395e3efd304 100644 (file)
--- a/include/linux/memory_hotplug.h
+++ b/include/linux/memory_hotplug.h
@@ -165,6 +165,12 @@ extern void register_page_bootmem_info_node(struct pglist_data *pgdat);
 extern void put_page_bootmem(struct page *page);
 #endif
 
+/*
+ * Lock for memory hotplug guarantees 1) all callbacks for memory hotplug
+ * notifier will be called under this. 2) offline/online/add/remove memory
+ * will not run simultaneously.
+ */
+
 void lock_memory_hotplug(void);
 void unlock_memory_hotplug(void);
 

diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index e92f04749fcb23fa283642dbb2a00dcda1ccd38d..321fc7455df7328c08441b54300054ff963e487b 100644 (file)
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -409,6 +409,7 @@ int online_pages(unsigned long pfn, unsigned long nr_pages)
        int ret;
        struct memory_notify arg;
 
+       lock_memory_hotplug();
        arg.start_pfn = pfn;
        arg.nr_pages = nr_pages;
        arg.status_change_nid = -1;
@@ -421,6 +422,7 @@ int online_pages(unsigned long pfn, unsigned long nr_pages)
        ret = notifier_to_errno(ret);
        if (ret) {
                memory_notify(MEM_CANCEL_ONLINE, &arg);
+               unlock_memory_hotplug();
                return ret;
        }
        /*
@@ -445,6 +447,7 @@ int online_pages(unsigned long pfn, unsigned long nr_pages)
                printk(KERN_DEBUG "online_pages %lx at %lx failed\n",
                        nr_pages, pfn);
                memory_notify(MEM_CANCEL_ONLINE, &arg);
+               unlock_memory_hotplug();
                return ret;
        }
 
@@ -469,6 +472,7 @@ int online_pages(unsigned long pfn, unsigned long nr_pages)
 
        if (onlined_pages)
                memory_notify(MEM_ONLINE, &arg);
+       unlock_memory_hotplug();
 
        return 0;
 }

diff --git a/mm/slub.c b/mm/slub.c
index c7ef0070dd864efd8bd2261c428228cbffbabe44..e15aa7f193c9734518f3c3508210c70f294e4ad3 100644 (file)
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -3797,7 +3797,7 @@ static ssize_t show_slab_objects(struct kmem_cache *s,
                }
        }
 
-       down_read(&slub_lock);
+       lock_memory_hotplug();
 #ifdef CONFIG_SLUB_DEBUG
        if (flags & SO_ALL) {
                for_each_node_state(node, N_NORMAL_MEMORY) {
@@ -3838,7 +3838,7 @@ static ssize_t show_slab_objects(struct kmem_cache *s,
                        x += sprintf(buf + x, " N%d=%lu",
                                        node, nodes[node]);
 #endif
-       up_read(&slub_lock);
+       unlock_memory_hotplug();
        kfree(nodes);
        return x + sprintf(buf + x, "\n");
 }