summaryrefslogtreecommitdiff
path: root/include
diff options
context:
space:
mode:
authorKuniyuki Iwashima <kuniyu@amazon.com>2024-10-05 01:10:29 +0300
committerPaolo Abeni <pabeni@redhat.com>2024-10-08 16:16:59 +0300
commit76aed95319da25d6884dff01d5f0149e4b542f96 (patch)
treea4abd91a746cb82930cf34c1b588cb12e8613d4e /include
parentec763c234d7f60c5bce0fa2611ba79f5be1af76b (diff)
downloadlinux-76aed95319da25d6884dff01d5f0149e4b542f96.tar.xz
rtnetlink: Add per-netns RTNL.
The goal is to break RTNL down into per-netns mutex. This patch adds per-netns mutex and its helper functions, rtnl_net_lock() and rtnl_net_unlock(). rtnl_net_lock() acquires the global RTNL and per-netns RTNL mutex, and rtnl_net_unlock() releases them. We will replace 800+ rtnl_lock() with rtnl_net_lock() and finally removes rtnl_lock() in rtnl_net_lock(). When we need to nest per-netns RTNL mutex, we will use __rtnl_net_lock(), and its locking order is defined by rtnl_net_lock_cmp_fn() as follows: 1. init_net is first 2. netns address ascending order Note that the conversion will be done under CONFIG_DEBUG_NET_SMALL_RTNL with LOCKDEP so that we can carefully add the extra mutex without slowing down RTNL operations during conversion. Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Diffstat (limited to 'include')
-rw-r--r--include/linux/rtnetlink.h21
-rw-r--r--include/net/net_namespace.h4
2 files changed, 25 insertions, 0 deletions
diff --git a/include/linux/rtnetlink.h b/include/linux/rtnetlink.h
index cdfc897f1e3c..edd840a49989 100644
--- a/include/linux/rtnetlink.h
+++ b/include/linux/rtnetlink.h
@@ -92,6 +92,27 @@ static inline bool lockdep_rtnl_is_held(void)
#define rcu_replace_pointer_rtnl(rp, p) \
rcu_replace_pointer(rp, p, lockdep_rtnl_is_held())
+#ifdef CONFIG_DEBUG_NET_SMALL_RTNL
+void __rtnl_net_lock(struct net *net);
+void __rtnl_net_unlock(struct net *net);
+void rtnl_net_lock(struct net *net);
+void rtnl_net_unlock(struct net *net);
+int rtnl_net_lock_cmp_fn(const struct lockdep_map *a, const struct lockdep_map *b);
+#else
+static inline void __rtnl_net_lock(struct net *net) {}
+static inline void __rtnl_net_unlock(struct net *net) {}
+
+static inline void rtnl_net_lock(struct net *net)
+{
+ rtnl_lock();
+}
+
+static inline void rtnl_net_unlock(struct net *net)
+{
+ rtnl_unlock();
+}
+#endif
+
static inline struct netdev_queue *dev_ingress_queue(struct net_device *dev)
{
return rtnl_dereference(dev->ingress_queue);
diff --git a/include/net/net_namespace.h b/include/net/net_namespace.h
index e67b483cc8bb..873c0f9fdac6 100644
--- a/include/net/net_namespace.h
+++ b/include/net/net_namespace.h
@@ -188,6 +188,10 @@ struct net {
#if IS_ENABLED(CONFIG_SMC)
struct netns_smc smc;
#endif
+#ifdef CONFIG_DEBUG_NET_SMALL_RTNL
+ /* Move to a better place when the config guard is removed. */
+ struct mutex rtnl_mutex;
+#endif
} __randomize_layout;
#include <linux/seq_file_net.h>