From cda1fd4abd773216a888487af0170d0cc3d50454 Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Tue, 6 Mar 2007 01:42:22 -0800 Subject: [PATCH] [PATCH] knfsd: fix recently introduced problem with shutting down a busy NFS server When the last thread of nfsd exits, it shuts down all related sockets. It currently uses svc_close_socket to do this, but that only is immediately effective if the socket is not SK_BUSY. If the socket is busy - i.e. if a request has arrived that has not yet been processes - svc_close_socket is not effective and the shutdown process spins. So create a new svc_force_close_socket which removes the SK_BUSY flag is set and then calls svc_close_socket. Also change some open-codes loops in svc_destroy to use list_for_each_entry_safe. Signed-off-by: Neil Brown Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/sunrpc/svcsock.h | 2 +- net/sunrpc/svc.c | 21 +++++++++------------ net/sunrpc/svcsock.c | 16 +++++++++++++++- 3 files changed, 25 insertions(+), 14 deletions(-) diff --git a/include/linux/sunrpc/svcsock.h b/include/linux/sunrpc/svcsock.h index cccea0a0fe..7909687557 100644 --- a/include/linux/sunrpc/svcsock.h +++ b/include/linux/sunrpc/svcsock.h @@ -66,7 +66,7 @@ struct svc_sock { * Function prototypes. */ int svc_makesock(struct svc_serv *, int, unsigned short, int flags); -void svc_close_socket(struct svc_sock *); +void svc_force_close_socket(struct svc_sock *); int svc_recv(struct svc_rqst *, long); int svc_send(struct svc_rqst *); void svc_drop(struct svc_rqst *); diff --git a/net/sunrpc/svc.c b/net/sunrpc/svc.c index 8353829bc5..f960b13823 100644 --- a/net/sunrpc/svc.c +++ b/net/sunrpc/svc.c @@ -367,6 +367,7 @@ void svc_destroy(struct svc_serv *serv) { struct svc_sock *svsk; + struct svc_sock *tmp; dprintk("svc: svc_destroy(%s, %d)\n", serv->sv_program->pg_name, @@ -382,21 +383,17 @@ svc_destroy(struct svc_serv *serv) del_timer_sync(&serv->sv_temptimer); - while (!list_empty(&serv->sv_tempsocks)) { - svsk = list_entry(serv->sv_tempsocks.next, - struct svc_sock, - sk_list); - svc_close_socket(svsk); - } + list_for_each_entry_safe(svsk, tmp, &serv->sv_tempsocks, sk_list) + svc_force_close_socket(svsk); + if (serv->sv_shutdown) serv->sv_shutdown(serv); - while (!list_empty(&serv->sv_permsocks)) { - svsk = list_entry(serv->sv_permsocks.next, - struct svc_sock, - sk_list); - svc_close_socket(svsk); - } + list_for_each_entry_safe(svsk, tmp, &serv->sv_permsocks, sk_list) + svc_force_close_socket(svsk); + + BUG_ON(!list_empty(&serv->sv_permsocks)); + BUG_ON(!list_empty(&serv->sv_tempsocks)); cache_clean_deferred(serv); diff --git a/net/sunrpc/svcsock.c b/net/sunrpc/svcsock.c index e957ce55fd..f6e1eb1ea7 100644 --- a/net/sunrpc/svcsock.c +++ b/net/sunrpc/svcsock.c @@ -82,6 +82,7 @@ static void svc_delete_socket(struct svc_sock *svsk); static void svc_udp_data_ready(struct sock *, int); static int svc_udp_recvfrom(struct svc_rqst *); static int svc_udp_sendto(struct svc_rqst *); +static void svc_close_socket(struct svc_sock *svsk); static struct svc_deferred_req *svc_deferred_dequeue(struct svc_sock *svsk); static int svc_deferred_recv(struct svc_rqst *rqstp); @@ -1787,7 +1788,7 @@ svc_delete_socket(struct svc_sock *svsk) spin_unlock_bh(&serv->sv_lock); } -void svc_close_socket(struct svc_sock *svsk) +static void svc_close_socket(struct svc_sock *svsk) { set_bit(SK_CLOSE, &svsk->sk_flags); if (test_and_set_bit(SK_BUSY, &svsk->sk_flags)) @@ -1800,6 +1801,19 @@ void svc_close_socket(struct svc_sock *svsk) svc_sock_put(svsk); } +void svc_force_close_socket(struct svc_sock *svsk) +{ + set_bit(SK_CLOSE, &svsk->sk_flags); + if (test_bit(SK_BUSY, &svsk->sk_flags)) { + /* Waiting to be processed, but no threads left, + * So just remove it from the waiting list + */ + list_del_init(&svsk->sk_ready); + clear_bit(SK_BUSY, &svsk->sk_flags); + } + svc_close_socket(svsk); +} + /** * svc_makesock - Make a socket for nfsd and lockd * @serv: RPC server structure -- 2.39.5