nfsd/sunrpc: factor svc_rqst allocation and freeing from sv_nrthreads refcounting

In later patches, we'll want to be able to allocate and free svc_rqst
structures without monkeying with the serv->sv_nrthreads refcount.

Factor those pieces out of their respective functions.

Signed-off-by: Shirley Ma <shirley.ma@oracle.com>
Acked-by: Jeff Layton <jlayton@primarydata.com>
Tested-by: Shirley Ma <shirley.ma@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

diff --git a/include/linux/sunrpc/svc.h b/include/linux/sunrpc/svc.h
index 3a9baea..cc0fc71 100644 (file)
--- a/include/linux/sunrpc/svc.h
+++ b/include/linux/sunrpc/svc.h
@@ -458,8 +458,11 @@ void svc_rpcb_cleanup(struct svc_serv *serv, struct net *net);
 int svc_bind(struct svc_serv *serv, struct net *net);
 struct svc_serv *svc_create(struct svc_program *, unsigned int,
                            struct svc_serv_ops *);
+struct svc_rqst *svc_rqst_alloc(struct svc_serv *serv,
+                                       struct svc_pool *pool, int node);
 struct svc_rqst *svc_prepare_thread(struct svc_serv *serv,
                                        struct svc_pool *pool, int node);
+void              svc_rqst_free(struct svc_rqst *);
 void              svc_exit_thread(struct svc_rqst *);
 unsigned int      svc_pool_map_get(void);
 void              svc_pool_map_put(void);

diff --git a/net/sunrpc/svc.c b/net/sunrpc/svc.c
index 486c14b..a8f579d 100644 (file)
--- a/net/sunrpc/svc.c
+++ b/net/sunrpc/svc.c
@@ -583,40 +583,52 @@ svc_release_buffer(struct svc_rqst *rqstp)
 }
 
 struct svc_rqst *
-svc_prepare_thread(struct svc_serv *serv, struct svc_pool *pool, int node)
+svc_rqst_alloc(struct svc_serv *serv, struct svc_pool *pool, int node)
 {
        struct svc_rqst *rqstp;
 
        rqstp = kzalloc_node(sizeof(*rqstp), GFP_KERNEL, node);
        if (!rqstp)
-               goto out_enomem;
+               return rqstp;
 
-       serv->sv_nrthreads++;
        __set_bit(RQ_BUSY, &rqstp->rq_flags);
        spin_lock_init(&rqstp->rq_lock);
        rqstp->rq_server = serv;
        rqstp->rq_pool = pool;
-       spin_lock_bh(&pool->sp_lock);
-       pool->sp_nrthreads++;
-       list_add_rcu(&rqstp->rq_all, &pool->sp_all_threads);
-       spin_unlock_bh(&pool->sp_lock);
 
        rqstp->rq_argp = kmalloc_node(serv->sv_xdrsize, GFP_KERNEL, node);
        if (!rqstp->rq_argp)
-               goto out_thread;
+               goto out_enomem;
 
        rqstp->rq_resp = kmalloc_node(serv->sv_xdrsize, GFP_KERNEL, node);
        if (!rqstp->rq_resp)
-               goto out_thread;
+               goto out_enomem;
 
        if (!svc_init_buffer(rqstp, serv->sv_max_mesg, node))
-               goto out_thread;
+               goto out_enomem;
 
        return rqstp;
-out_thread:
-       svc_exit_thread(rqstp);
 out_enomem:
-       return ERR_PTR(-ENOMEM);
+       svc_rqst_free(rqstp);
+       return NULL;
+}
+EXPORT_SYMBOL_GPL(svc_rqst_alloc);
+
+struct svc_rqst *
+svc_prepare_thread(struct svc_serv *serv, struct svc_pool *pool, int node)
+{
+       struct svc_rqst *rqstp;
+
+       rqstp = svc_rqst_alloc(serv, pool, node);
+       if (!rqstp)
+               return ERR_PTR(-ENOMEM);
+
+       serv->sv_nrthreads++;
+       spin_lock_bh(&pool->sp_lock);
+       pool->sp_nrthreads++;
+       list_add_rcu(&rqstp->rq_all, &pool->sp_all_threads);
+       spin_unlock_bh(&pool->sp_lock);
+       return rqstp;
 }
 EXPORT_SYMBOL_GPL(svc_prepare_thread);
 
@@ -751,15 +763,21 @@ EXPORT_SYMBOL_GPL(svc_set_num_threads);
  * mutex" for the service.
  */
 void
-svc_exit_thread(struct svc_rqst *rqstp)
+svc_rqst_free(struct svc_rqst *rqstp)
 {
-       struct svc_serv *serv = rqstp->rq_server;
-       struct svc_pool *pool = rqstp->rq_pool;
-
        svc_release_buffer(rqstp);
        kfree(rqstp->rq_resp);
        kfree(rqstp->rq_argp);
        kfree(rqstp->rq_auth_data);
+       kfree_rcu(rqstp, rq_rcu_head);
+}
+EXPORT_SYMBOL_GPL(svc_rqst_free);
+
+void
+svc_exit_thread(struct svc_rqst *rqstp)
+{
+       struct svc_serv *serv = rqstp->rq_server;
+       struct svc_pool *pool = rqstp->rq_pool;
 
        spin_lock_bh(&pool->sp_lock);
        pool->sp_nrthreads--;
@@ -767,7 +785,7 @@ svc_exit_thread(struct svc_rqst *rqstp)
                list_del_rcu(&rqstp->rq_all);
        spin_unlock_bh(&pool->sp_lock);
 
-       kfree_rcu(rqstp, rq_rcu_head);
+       svc_rqst_free(rqstp);
 
        /* Release the server */
        if (serv)