NFSv4: Fix callback server shutdown
We want to use kthread_stop() in order to ensure the threads are
shut down before we tear down the nfs_callback_info in nfs_callback_down.
Tested-and-reviewed-by: Kinglong Mee <kinglongmee@gmail.com>
Reported-by: Kinglong Mee <kinglongmee@gmail.com>
Fixes: bb6aeba736ba9 ("NFSv4.x: Switch to using svc_set_num_threads()...")
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
diff --git a/net/sunrpc/svc.c b/net/sunrpc/svc.c
index 98dc33a..bc0f5a0 100644
--- a/net/sunrpc/svc.c
+++ b/net/sunrpc/svc.c
@@ -795,6 +795,44 @@
}
EXPORT_SYMBOL_GPL(svc_set_num_threads);
+/* destroy old threads */
+static int
+svc_stop_kthreads(struct svc_serv *serv, struct svc_pool *pool, int nrservs)
+{
+ struct task_struct *task;
+ unsigned int state = serv->sv_nrthreads-1;
+
+ /* destroy old threads */
+ do {
+ task = choose_victim(serv, pool, &state);
+ if (task == NULL)
+ break;
+ kthread_stop(task);
+ nrservs++;
+ } while (nrservs < 0);
+ return 0;
+}
+
+int
+svc_set_num_threads_sync(struct svc_serv *serv, struct svc_pool *pool, int nrservs)
+{
+ if (pool == NULL) {
+ /* The -1 assumes caller has done a svc_get() */
+ nrservs -= (serv->sv_nrthreads-1);
+ } else {
+ spin_lock_bh(&pool->sp_lock);
+ nrservs -= pool->sp_nrthreads;
+ spin_unlock_bh(&pool->sp_lock);
+ }
+
+ if (nrservs > 0)
+ return svc_start_kthreads(serv, pool, nrservs);
+ if (nrservs < 0)
+ return svc_stop_kthreads(serv, pool, nrservs);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(svc_set_num_threads_sync);
+
/*
* Called from a server thread as it's exiting. Caller must hold the "service
* mutex" for the service.