From ed07536ed6731775219c1df7fa26a7588753e693 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Wed, 6 Dec 2006 20:35:24 -0800 Subject: [PATCH] [PATCH] lockdep: annotate nfs/nfsd in-kernel sockets Stick NFS sockets in their own class to avoid some lockdep warnings. NFS sockets are never exposed to user-space, and will hence not trigger certain code paths that would otherwise pose deadlock scenarios. [akpm@osdl.org: cleanups] Signed-off-by: Peter Zijlstra Signed-off-by: Steven Dickson Acked-by: Ingo Molnar Cc: Trond Myklebust Acked-by: Neil Brown Cc: "David S. Miller" Signed-off-by: Andrew Morton [ Fixed patch corruption by quilt, pointed out by Peter Zijlstra ] Signed-off-by: Linus Torvalds --- include/net/sock.h | 19 +++++++++++++++++++ kernel/lockdep.c | 1 + net/core/sock.c | 23 +++++------------------ net/sunrpc/svcsock.c | 31 +++++++++++++++++++++++++++++++ net/sunrpc/xprtsock.c | 31 +++++++++++++++++++++++++++++++ 5 files changed, 87 insertions(+), 18 deletions(-) diff --git a/include/net/sock.h b/include/net/sock.h index 730899c..03684e7 100644 --- a/include/net/sock.h +++ b/include/net/sock.h @@ -746,6 +746,25 @@ static inline int sk_stream_wmem_schedule(struct sock *sk, int size) */ #define sock_owned_by_user(sk) ((sk)->sk_lock.owner) +/* + * Macro so as to not evaluate some arguments when + * lockdep is not enabled. + * + * Mark both the sk_lock and the sk_lock.slock as a + * per-address-family lock class. + */ +#define sock_lock_init_class_and_name(sk, sname, skey, name, key) \ +do { \ + sk->sk_lock.owner = NULL; \ + init_waitqueue_head(&sk->sk_lock.wq); \ + spin_lock_init(&(sk)->sk_lock.slock); \ + debug_check_no_locks_freed((void *)&(sk)->sk_lock, \ + sizeof((sk)->sk_lock)); \ + lockdep_set_class_and_name(&(sk)->sk_lock.slock, \ + (skey), (sname)); \ + lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0); \ +} while (0) + extern void FASTCALL(lock_sock_nested(struct sock *sk, int subclass)); static inline void lock_sock(struct sock *sk) diff --git a/kernel/lockdep.c b/kernel/lockdep.c index c9fefdb..e33f620 100644 --- a/kernel/lockdep.c +++ b/kernel/lockdep.c @@ -2645,6 +2645,7 @@ void debug_check_no_locks_freed(const void *mem_from, unsigned long mem_len) } local_irq_restore(flags); } +EXPORT_SYMBOL_GPL(debug_check_no_locks_freed); static void print_held_locks_bug(struct task_struct *curr) { diff --git a/net/core/sock.c b/net/core/sock.c index 4a432da..0ed5b4f 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -810,24 +810,11 @@ lenout: */ static void inline sock_lock_init(struct sock *sk) { - spin_lock_init(&sk->sk_lock.slock); - sk->sk_lock.owner = NULL; - init_waitqueue_head(&sk->sk_lock.wq); - /* - * Make sure we are not reinitializing a held lock: - */ - debug_check_no_locks_freed((void *)&sk->sk_lock, sizeof(sk->sk_lock)); - - /* - * Mark both the sk_lock and the sk_lock.slock as a - * per-address-family lock class: - */ - lockdep_set_class_and_name(&sk->sk_lock.slock, - af_family_slock_keys + sk->sk_family, - af_family_slock_key_strings[sk->sk_family]); - lockdep_init_map(&sk->sk_lock.dep_map, - af_family_key_strings[sk->sk_family], - af_family_keys + sk->sk_family, 0); + sock_lock_init_class_and_name(sk, + af_family_slock_key_strings[sk->sk_family], + af_family_slock_keys + sk->sk_family, + af_family_key_strings[sk->sk_family], + af_family_keys + sk->sk_family); } /** diff --git a/net/sunrpc/svcsock.c b/net/sunrpc/svcsock.c index 1c68956..99f54fb 100644 --- a/net/sunrpc/svcsock.c +++ b/net/sunrpc/svcsock.c @@ -85,6 +85,35 @@ static struct cache_deferred_req *svc_defer(struct cache_req *req); */ static int svc_conn_age_period = 6*60; +#ifdef CONFIG_DEBUG_LOCK_ALLOC +static struct lock_class_key svc_key[2]; +static struct lock_class_key svc_slock_key[2]; + +static inline void svc_reclassify_socket(struct socket *sock) +{ + struct sock *sk = sock->sk; + BUG_ON(sk->sk_lock.owner != NULL); + switch (sk->sk_family) { + case AF_INET: + sock_lock_init_class_and_name(sk, "slock-AF_INET-NFSD", + &svc_slock_key[0], "sk_lock-AF_INET-NFSD", &svc_key[0]); + break; + + case AF_INET6: + sock_lock_init_class_and_name(sk, "slock-AF_INET6-NFSD", + &svc_slock_key[1], "sk_lock-AF_INET6-NFSD", &svc_key[1]); + break; + + default: + BUG(); + } +} +#else +static inline void svc_reclassify_socket(struct socket *sock) +{ +} +#endif + /* * Queue up an idle server thread. Must have pool->sp_lock held. * Note: this is really a stack rather than a queue, so that we only @@ -1557,6 +1586,8 @@ svc_create_socket(struct svc_serv *serv, int protocol, struct sockaddr_in *sin) if ((error = sock_create_kern(PF_INET, type, protocol, &sock)) < 0) return error; + svc_reclassify_socket(sock); + if (type == SOCK_STREAM) sock->sk->sk_reuse = 1; /* allow address reuse */ error = kernel_bind(sock, (struct sockaddr *) sin, diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c index cfe3c15..2fc4a31 100644 --- a/net/sunrpc/xprtsock.c +++ b/net/sunrpc/xprtsock.c @@ -1058,6 +1058,35 @@ static int xs_bindresvport(struct rpc_xprt *xprt, struct socket *sock) return err; } +#ifdef CONFIG_DEBUG_LOCK_ALLOC +static struct lock_class_key xs_key[2]; +static struct lock_class_key xs_slock_key[2]; + +static inline void xs_reclassify_socket(struct socket *sock) +{ + struct sock *sk = sock->sk; + BUG_ON(sk->sk_lock.owner != NULL); + switch (sk->sk_family) { + case AF_INET: + sock_lock_init_class_and_name(sk, "slock-AF_INET-NFS", + &xs_slock_key[0], "sk_lock-AF_INET-NFS", &xs_key[0]); + break; + + case AF_INET6: + sock_lock_init_class_and_name(sk, "slock-AF_INET6-NFS", + &xs_slock_key[1], "sk_lock-AF_INET6-NFS", &xs_key[1]); + break; + + default: + BUG(); + } +} +#else +static inline void xs_reclassify_socket(struct socket *sock) +{ +} +#endif + /** * xs_udp_connect_worker - set up a UDP socket * @work: RPC transport to connect @@ -1081,6 +1110,7 @@ static void xs_udp_connect_worker(struct work_struct *work) dprintk("RPC: can't create UDP transport socket (%d).\n", -err); goto out; } + xs_reclassify_socket(sock); if (xprt->resvport && xs_bindresvport(xprt, sock) < 0) { sock_release(sock); @@ -1165,6 +1195,7 @@ static void xs_tcp_connect_worker(struct work_struct *work) dprintk("RPC: can't create TCP transport socket (%d).\n", -err); goto out; } + xs_reclassify_socket(sock); if (xprt->resvport && xs_bindresvport(xprt, sock) < 0) { sock_release(sock); -- 2.7.4