Using sv_lock means we don't need to hold the service mutex over these updates. In particular, svc_exit_thread() no longer requires synchronisation, so threads can exit asynchronously. Signed-off-by: NeilBrown <neilb@xxxxxxx> --- fs/nfsd/nfssvc.c | 9 ++++----- net/sunrpc/svc.c | 9 +++++++-- 2 files changed, 11 insertions(+), 7 deletions(-) diff --git a/fs/nfsd/nfssvc.c b/fs/nfsd/nfssvc.c index 9e517ddd8d4e..27a735a4df29 100644 --- a/fs/nfsd/nfssvc.c +++ b/fs/nfsd/nfssvc.c @@ -55,9 +55,8 @@ static __be32 nfsd_init_request(struct svc_rqst *, struct svc_process_info *); /* - * nfsd_mutex protects nn->nfsd_serv -- both the pointer itself and the members - * of the svc_serv struct. In particular, ->sv_nrthreads but also to some - * extent ->sv_temp_socks and ->sv_permsocks. + * nfsd_mutex protects nn->nfsd_serv -- both the pointer itself and some members + * of the svc_serv struct such as ->sv_temp_socks and ->sv_permsocks. * * If (out side the lock) nn->nfsd_serv is non-NULL, then it must point to a * properly initialised 'struct svc_serv' with ->sv_nrthreads > 0 (unless @@ -983,7 +982,6 @@ nfsd(void *vrqstp) atomic_dec(&nfsdstats.th_cnt); out: - mutex_lock(&nfsd_mutex); /* Take an extra ref so that the svc_put in svc_exit_thread() * doesn't call svc_destroy() */ @@ -993,10 +991,11 @@ nfsd(void *vrqstp) svc_exit_thread(rqstp); /* Now if needed we call svc_destroy in appropriate context */ + mutex_lock(&nfsd_mutex); nfsd_put(net); + mutex_unlock(&nfsd_mutex); /* Release module */ - mutex_unlock(&nfsd_mutex); module_put_and_exit(0); return 0; } diff --git a/net/sunrpc/svc.c b/net/sunrpc/svc.c index bd610709e88c..a099d0145d89 100644 --- a/net/sunrpc/svc.c +++ b/net/sunrpc/svc.c @@ -523,7 +523,7 @@ EXPORT_SYMBOL_GPL(svc_shutdown_net); /* * Destroy an RPC service. Should be called with appropriate locking to - * protect the sv_nrthreads, sv_permsocks and sv_tempsocks. + * protect sv_permsocks and sv_tempsocks. */ void svc_destroy(struct kref *ref) @@ -641,7 +641,10 @@ svc_prepare_thread(struct svc_serv *serv, struct svc_pool *pool, int node) return ERR_PTR(-ENOMEM); svc_get(serv); - serv->sv_nrthreads++; + spin_lock_bh(&serv->sv_lock); + serv->sv_nrthreads += 1; + spin_unlock_bh(&serv->sv_lock); + spin_lock_bh(&pool->sp_lock); pool->sp_nrthreads++; list_add_rcu(&rqstp->rq_all, &pool->sp_all_threads); @@ -882,7 +885,9 @@ svc_exit_thread(struct svc_rqst *rqstp) list_del_rcu(&rqstp->rq_all); spin_unlock_bh(&pool->sp_lock); + spin_lock_bh(&serv->sv_lock); serv->sv_nrthreads -= 1; + spin_unlock_bh(&serv->sv_lock); svc_sock_update_bufs(serv); svc_rqst_free(rqstp);
