[NET]: Define infrastructure to keep 'inuse' changes in an efficent SMP/NUMA way.

[safe/jmp/linux-2.6] / net / core / sock.c

diff --git a/net/core/sock.c b/net/core/sock.c
index 12ad206..e077f26 100644 (file)
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -1801,12 +1801,41 @@ EXPORT_SYMBOL(sk_common_release);
 static DEFINE_RWLOCK(proto_list_lock);
 static LIST_HEAD(proto_list);
 
+#ifdef CONFIG_SMP
+/*
+ * Define default functions to keep track of inuse sockets per protocol
+ * Note that often used protocols use dedicated functions to get a speed increase.
+ * (see DEFINE_PROTO_INUSE/REF_PROTO_INUSE)
+ */
+static void inuse_add(struct proto *prot, int inc)
+{
+       per_cpu_ptr(prot->inuse_ptr, smp_processor_id())[0] += inc;
+}
+
+static int inuse_get(const struct proto *prot)
+{
+       int res = 0, cpu;
+       for_each_possible_cpu(cpu)
+               res += per_cpu_ptr(prot->inuse_ptr, cpu)[0];
+       return res;
+}
+#endif
+
 int proto_register(struct proto *prot, int alloc_slab)
 {
        char *request_sock_slab_name = NULL;
        char *timewait_sock_slab_name;
        int rc = -ENOBUFS;
 
+#ifdef CONFIG_SMP
+       if (!prot->inuse_getval || !prot->inuse_add) {
+               prot->inuse_ptr = alloc_percpu(int);
+               if (prot->inuse_ptr == NULL)
+                       goto out;
+               prot->inuse_getval = inuse_get;
+               prot->inuse_add = inuse_add;
+       }
+#endif
        if (alloc_slab) {
                prot->slab = kmem_cache_create(prot->name, prot->obj_size, 0,
                                               SLAB_HWCACHE_ALIGN, NULL);
@@ -1814,7 +1843,7 @@ int proto_register(struct proto *prot, int alloc_slab)
                if (prot->slab == NULL) {
                        printk(KERN_CRIT "%s: Can't create sock SLAB cache!\n",
                               prot->name);
-                       goto out;
+                       goto out_free_inuse;
                }
 
                if (prot->rsk_prot != NULL) {
@@ -1873,6 +1902,15 @@ out_free_request_sock_slab_name:
 out_free_sock_slab:
        kmem_cache_destroy(prot->slab);
        prot->slab = NULL;
+out_free_inuse:
+#ifdef CONFIG_SMP
+       if (prot->inuse_ptr != NULL) {
+               free_percpu(prot->inuse_ptr);
+               prot->inuse_ptr = NULL;
+               prot->inuse_getval = NULL;
+               prot->inuse_add = NULL;
+       }
+#endif
        goto out;
 }
 
@@ -1884,6 +1922,14 @@ void proto_unregister(struct proto *prot)
        list_del(&prot->node);
        write_unlock(&proto_list_lock);
 
+#ifdef CONFIG_SMP
+       if (prot->inuse_ptr != NULL) {
+               free_percpu(prot->inuse_ptr);
+               prot->inuse_ptr = NULL;
+               prot->inuse_getval = NULL;
+               prot->inuse_add = NULL;
+       }
+#endif
        if (prot->slab != NULL) {
                kmem_cache_destroy(prot->slab);
                prot->slab = NULL;