[PATCH net 5/9] wireguard: peer: allocate in kmem_cache
From: "Jason A. Donenfeld" <Jason@zx2c4.com>
Date: 2021-06-04 15:18:09
Also in:
stable
Subsystem:
networking drivers, the rest, wireguard secure network tunnel · Maintainers:
Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds, Jason A. Donenfeld
With deployments having upwards of 600k peers now, this somewhat heavy
structure could benefit from more fine-grained allocations.
Specifically, instead of using a 2048-byte slab for a 1544-byte object,
we can now use 1544-byte objects directly, thus saving almost 25%
per-peer, or with 600k peers, that's a savings of 303 MiB. This also
makes wireguard's memory usage more transparent in tools like slabtop
and /proc/slabinfo.
Fixes: 8b5553ace83c ("wireguard: queueing: get rid of per-peer ring buffers")
Suggested-by: Arnd Bergmann <arnd@arndb.de>
Suggested-by: Matthew Wilcox <willy@infradead.org>
Cc: stable@vger.kernel.org
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
---
drivers/net/wireguard/main.c | 7 +++++++
drivers/net/wireguard/peer.c | 21 +++++++++++++++++----
drivers/net/wireguard/peer.h | 3 +++
3 files changed, 27 insertions(+), 4 deletions(-)
diff --git a/drivers/net/wireguard/main.c b/drivers/net/wireguard/main.c
index 7a7d5f1a80fc..0a3ebfdac794 100644
--- a/drivers/net/wireguard/main.c
+++ b/drivers/net/wireguard/main.c@@ -28,6 +28,10 @@ static int __init mod_init(void) #endif wg_noise_init(); + ret = wg_peer_init(); + if (ret < 0) + goto err_peer; + ret = wg_device_init(); if (ret < 0) goto err_device;
@@ -44,6 +48,8 @@ static int __init mod_init(void) err_netlink: wg_device_uninit(); err_device: + wg_peer_uninit(); +err_peer: return ret; }
@@ -51,6 +57,7 @@ static void __exit mod_exit(void) { wg_genetlink_uninit(); wg_device_uninit(); + wg_peer_uninit(); } module_init(mod_init);
diff --git a/drivers/net/wireguard/peer.c b/drivers/net/wireguard/peer.c
index 3a042d28eb2e..1acd00ab2fbc 100644
--- a/drivers/net/wireguard/peer.c
+++ b/drivers/net/wireguard/peer.c@@ -15,6 +15,7 @@ #include <linux/rcupdate.h> #include <linux/list.h> +static struct kmem_cache *peer_cache; static atomic64_t peer_counter = ATOMIC64_INIT(0); struct wg_peer *wg_peer_create(struct wg_device *wg,
@@ -29,10 +30,10 @@ struct wg_peer *wg_peer_create(struct wg_device *wg, if (wg->num_peers >= MAX_PEERS_PER_DEVICE) return ERR_PTR(ret); - peer = kzalloc(sizeof(*peer), GFP_KERNEL); + peer = kmem_cache_zalloc(peer_cache, GFP_KERNEL); if (unlikely(!peer)) return ERR_PTR(ret); - if (dst_cache_init(&peer->endpoint_cache, GFP_KERNEL)) + if (unlikely(dst_cache_init(&peer->endpoint_cache, GFP_KERNEL))) goto err; peer->device = wg;
@@ -64,7 +65,7 @@ struct wg_peer *wg_peer_create(struct wg_device *wg, return peer; err: - kfree(peer); + kmem_cache_free(peer_cache, peer); return ERR_PTR(ret); }
@@ -193,7 +194,8 @@ static void rcu_release(struct rcu_head *rcu) /* The final zeroing takes care of clearing any remaining handshake key * material and other potentially sensitive information. */ - kfree_sensitive(peer); + memzero_explicit(peer, sizeof(*peer)); + kmem_cache_free(peer_cache, peer); } static void kref_release(struct kref *refcount)
@@ -225,3 +227,14 @@ void wg_peer_put(struct wg_peer *peer) return; kref_put(&peer->refcount, kref_release); } + +int __init wg_peer_init(void) +{ + peer_cache = KMEM_CACHE(wg_peer, 0); + return peer_cache ? 0 : -ENOMEM; +} + +void wg_peer_uninit(void) +{ + kmem_cache_destroy(peer_cache); +}
diff --git a/drivers/net/wireguard/peer.h b/drivers/net/wireguard/peer.h
index 8d53b687a1d1..76e4d3128ad4 100644
--- a/drivers/net/wireguard/peer.h
+++ b/drivers/net/wireguard/peer.h@@ -80,4 +80,7 @@ void wg_peer_put(struct wg_peer *peer); void wg_peer_remove(struct wg_peer *peer); void wg_peer_remove_all(struct wg_device *wg); +int wg_peer_init(void); +void wg_peer_uninit(void); + #endif /* _WG_PEER_H */
--
2.31.1