On Sun, May 15, 2016 at 01:15:15PM +0200, Sven Eckelmann wrote:
> TODO statistics, batadv_tt_roam_node?, batadv_tt_change_node?,
> batadv_tt_req_node?, ....
Some statistics here:
https://www.open-mesh.org/projects/batman-adv/wiki/Kmalloc-kmem-cache-tests
In a nutshell, on a small TP-Link TL-841NDv8 wireless router
(MIPS/AR9341), I was able to achieve 34% more global TT entries
(or 25% less RAM usage).
Regarding SLAB_HWCACHE_ALIGN, it did not seem to make much of a
difference. There is a slight tendency for less RAM usage without
this flag. But it is so small, that it might be a coincident, too.
And it is definitely negligable. At least for this architecture.
Regards, Linus
PS: I might make some more, pretty graphs for the other test
variables, too. But for now, there is just this one raw table for
that.
@@ -81,6 +81,12 @@ static void batadv_recv_handler_init(void);
static int __init batadv_init(void)
{
+ int ret;
+
+ ret = batadv_tt_cache_init();
+ if (ret < 0)
+ return ret;
+
INIT_LIST_HEAD(&batadv_hardif_list);
batadv_algo_init();
@@ -91,9 +97,8 @@ static int __init batadv_init(void)
batadv_nc_init();
batadv_event_workqueue = create_singlethread_workqueue("bat_events");
-
if (!batadv_event_workqueue)
- return -ENOMEM;
+ goto err_create_wq;
batadv_socket_init();
batadv_debugfs_init();
@@ -106,6 +111,11 @@ static int __init batadv_init(void)
BATADV_SOURCE_VERSION, BATADV_COMPAT_VERSION);
return 0;
+
+err_create_wq:
+ batadv_tt_cache_destroy();
+
+ return -ENOMEM;
}
static void __exit batadv_exit(void)
@@ -121,6 +131,8 @@ static void __exit batadv_exit(void)
batadv_event_workqueue = NULL;
rcu_barrier();
+
+ batadv_tt_cache_destroy();
}
int batadv_mesh_init(struct net_device *soft_iface)
@@ -22,12 +22,14 @@
#include <linux/bitops.h>
#include <linux/bug.h>
#include <linux/byteorder/generic.h>
+#include <linux/cache.h>
#include <linux/compiler.h>
#include <linux/crc32c.h>
#include <linux/errno.h>
#include <linux/etherdevice.h>
#include <linux/fs.h>
#include <linux/if_ether.h>
+#include <linux/init.h>
#include <linux/jhash.h>
#include <linux/jiffies.h>
#include <linux/kernel.h>
@@ -54,6 +56,10 @@
#include "soft-interface.h"
#include "tvlv.h"
+static struct kmem_cache *batadv_tl_cache __read_mostly;
+static struct kmem_cache *batadv_tg_cache __read_mostly;
+static struct kmem_cache *batadv_tt_orig_cache __read_mostly;
+
/* hash class keys */
static struct lock_class_key batadv_tt_local_hash_lock_class_key;
static struct lock_class_key batadv_tt_global_hash_lock_class_key;
@@ -205,6 +211,20 @@ batadv_tt_global_hash_find(struct batadv_priv *bat_priv, const u8 *addr,
}
/**
+ * batadv_tt_local_entry_free_rcu - free the tt_local_entry
+ * @rcu: rcu pointer of the tt_local_entry
+ */
+static void batadv_tt_local_entry_free_rcu(struct rcu_head *rcu)
+{
+ struct batadv_tt_local_entry *tt_local_entry;
+
+ tt_local_entry = container_of(rcu, struct batadv_tt_local_entry,
+ common.rcu);
+
+ kmem_cache_free(batadv_tl_cache, tt_local_entry);
+}
+
+/**
* batadv_tt_local_entry_release - release tt_local_entry from lists and queue
* for free after rcu grace period
* @ref: kref pointer of the nc_node
@@ -218,7 +238,7 @@ static void batadv_tt_local_entry_release(struct kref *ref)
batadv_softif_vlan_put(tt_local_entry->vlan);
- kfree_rcu(tt_local_entry, common.rcu);
+ call_rcu(&tt_local_entry->common.rcu, batadv_tt_local_entry_free_rcu);
}
/**
@@ -234,6 +254,20 @@ batadv_tt_local_entry_put(struct batadv_tt_local_entry *tt_local_entry)
}
/**
+ * batadv_tt_global_entry_free_rcu - free the tt_global_entry
+ * @rcu: rcu pointer of the tt_global_entry
+ */
+static void batadv_tt_global_entry_free_rcu(struct rcu_head *rcu)
+{
+ struct batadv_tt_global_entry *tt_global_entry;
+
+ tt_global_entry = container_of(rcu, struct batadv_tt_global_entry,
+ common.rcu);
+
+ kmem_cache_free(batadv_tg_cache, tt_global_entry);
+}
+
+/**
* batadv_tt_global_entry_release - release tt_global_entry from lists and queue
* for free after rcu grace period
* @ref: kref pointer of the nc_node
@@ -246,7 +280,8 @@ static void batadv_tt_global_entry_release(struct kref *ref)
common.refcount);
batadv_tt_global_del_orig_list(tt_global_entry);
- kfree_rcu(tt_global_entry, common.rcu);
+
+ call_rcu(&tt_global_entry->common.rcu, batadv_tt_global_entry_free_rcu);
}
/**
@@ -384,6 +419,19 @@ static void batadv_tt_global_size_dec(struct batadv_orig_node *orig_node,
}
/**
+ * batadv_tt_orig_list_entry_free_rcu - free the orig_entry
+ * @rcu: rcu pointer of the orig_entry
+ */
+static void batadv_tt_orig_list_entry_free_rcu(struct rcu_head *rcu)
+{
+ struct batadv_tt_orig_list_entry *orig_entry;
+
+ orig_entry = container_of(rcu, struct batadv_tt_orig_list_entry, rcu);
+
+ kmem_cache_free(batadv_tt_orig_cache, orig_entry);
+}
+
+/**
* batadv_tt_orig_list_entry_release - release tt orig entry from lists and
* queue for free after rcu grace period
* @ref: kref pointer of the tt orig entry
@@ -396,7 +444,7 @@ static void batadv_tt_orig_list_entry_release(struct kref *ref)
refcount);
batadv_orig_node_put(orig_entry->orig_node);
- kfree_rcu(orig_entry, rcu);
+ call_rcu(&orig_entry->rcu, batadv_tt_orig_list_entry_free_rcu);
}
/**
@@ -646,7 +694,7 @@ bool batadv_tt_local_add(struct net_device *soft_iface, const u8 *addr,
goto out;
}
- tt_local = kmalloc(sizeof(*tt_local), GFP_ATOMIC);
+ tt_local = kmem_cache_alloc(batadv_tl_cache, GFP_ATOMIC);
if (!tt_local)
goto out;
@@ -654,7 +702,7 @@ bool batadv_tt_local_add(struct net_device *soft_iface, const u8 *addr,
vlan = batadv_softif_vlan_get(bat_priv, vid);
if (WARN(!vlan, "adding TT local entry %pM to non-existent VLAN %d",
addr, BATADV_PRINT_VID(vid))) {
- kfree(tt_local);
+ kmem_cache_free(batadv_tl_cache, tt_local);
tt_local = NULL;
goto out;
}
@@ -1342,10 +1390,12 @@ batadv_tt_global_orig_entry_add(struct batadv_tt_global_entry *tt_global,
goto out;
}
- orig_entry = kzalloc(sizeof(*orig_entry), GFP_ATOMIC);
+ orig_entry = kmem_cache_alloc(batadv_tt_orig_cache, GFP_ATOMIC);
if (!orig_entry)
goto out;
+ memset(orig_entry, 0, sizeof(*orig_entry));
+
INIT_HLIST_NODE(&orig_entry->list);
kref_get(&orig_node->refcount);
batadv_tt_global_size_inc(orig_node, tt_global->common.vid);
@@ -1412,10 +1462,12 @@ static bool batadv_tt_global_add(struct batadv_priv *bat_priv,
goto out;
if (!tt_global_entry) {
- tt_global_entry = kzalloc(sizeof(*tt_global_entry), GFP_ATOMIC);
+ tt_global_entry = kmem_cache_alloc(batadv_tg_cache, GFP_ATOMIC);
if (!tt_global_entry)
goto out;
+ memset(tt_global_entry, 0, sizeof(*tt_global_entry));
+
common = &tt_global_entry->common;
ether_addr_copy(common->addr, tt_addr);
common->vid = vid;
@@ -3835,3 +3887,52 @@ bool batadv_tt_global_is_isolated(struct batadv_priv *bat_priv,
return ret;
}
+
+/**
+ * batadv_tt_cache_init - Initialize tt memory object cache
+ *
+ * Return: 0 on success or negative error number in case of failure.
+ */
+int __init batadv_tt_cache_init(void)
+{
+ size_t tl_size = sizeof(struct batadv_tt_local_entry);
+ size_t tg_size = sizeof(struct batadv_tt_global_entry);
+ size_t tt_orig_size = sizeof(struct batadv_tt_orig_list_entry);
+
+ batadv_tl_cache = kmem_cache_create("batadv_tl_cache", tl_size, 0,
+ SLAB_HWCACHE_ALIGN, NULL);
+ if (!batadv_tl_cache)
+ return -ENOMEM;
+
+ batadv_tg_cache = kmem_cache_create("batadv_tg_cache", tg_size, 0,
+ SLAB_HWCACHE_ALIGN, NULL);
+ if (!batadv_tg_cache)
+ goto err_tg_alloc;
+
+ batadv_tt_orig_cache = kmem_cache_create("batadv_tt_orig_cache",
+ tt_orig_size, 0,
+ SLAB_HWCACHE_ALIGN, NULL);
+ if (!batadv_tt_orig_cache)
+ goto err_tt_orig_alloc;
+
+ return 0;
+
+err_tt_orig_alloc:
+ kmem_cache_destroy(batadv_tg_cache);
+ batadv_tg_cache = NULL;
+err_tg_alloc:
+ kmem_cache_destroy(batadv_tl_cache);
+ batadv_tl_cache = NULL;
+
+ return -ENOMEM;
+}
+
+/**
+ * batadv_tt_cache_destroy - Destroy tt memory object cache
+ */
+void batadv_tt_cache_destroy(void)
+{
+ kmem_cache_destroy(batadv_tl_cache);
+ kmem_cache_destroy(batadv_tg_cache);
+ kmem_cache_destroy(batadv_tt_orig_cache);
+}
@@ -59,4 +59,7 @@ bool batadv_tt_add_temporary_global_entry(struct batadv_priv *bat_priv,
bool batadv_tt_global_is_isolated(struct batadv_priv *bat_priv,
const u8 *addr, unsigned short vid);
+int batadv_tt_cache_init(void);
+void batadv_tt_cache_destroy(void);
+
#endif /* _NET_BATMAN_ADV_TRANSLATION_TABLE_H_ */