Revert "cifs: No need to send SIGKILL to demux_thread during umount"

This reverts commit 52a36244443eabb594bdb63622ff2dd7a083f0e2.

Causes rmmod to fail for at least 7 seconds after unmount which
makes automated testing a little harder when reloading cifs.ko
between test runs.

Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
CC: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: Steve French <smfrench@gmail.com>

diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index 8a9fded7c135f6deb936873ad06fa86fc11c9f85..36ca2045009bf342ef507c132921484c7eaf7ded 100644 (file)
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -837,6 +837,7 @@ cifs_demultiplex_thread(void *p)
        struct TCP_Server_Info *server = p;
        unsigned int pdu_length;
        char *buf = NULL;
+       struct task_struct *task_to_wake = NULL;
        struct mid_q_entry *mid_entry;
 
        current->flags |= PF_MEMALLOC;
@@ -927,7 +928,19 @@ cifs_demultiplex_thread(void *p)
        if (server->smallbuf) /* no sense logging a debug message if NULL */
                cifs_small_buf_release(server->smallbuf);
 
+       task_to_wake = xchg(&server->tsk, NULL);
        clean_demultiplex_info(server);
+
+       /* if server->tsk was NULL then wait for a signal before exiting */
+       if (!task_to_wake) {
+               set_current_state(TASK_INTERRUPTIBLE);
+               while (!signal_pending(current)) {
+                       schedule();
+                       set_current_state(TASK_INTERRUPTIBLE);
+               }
+               set_current_state(TASK_RUNNING);
+       }
+
        module_put_and_exit(0);
 }
 
@@ -2050,6 +2063,8 @@ cifs_find_tcp_session(struct smb_vol *vol)
 static void
 cifs_put_tcp_session(struct TCP_Server_Info *server)
 {
+       struct task_struct *task;
+
        spin_lock(&cifs_tcp_ses_lock);
        if (--server->srv_count > 0) {
                spin_unlock(&cifs_tcp_ses_lock);
@@ -2073,6 +2088,10 @@ cifs_put_tcp_session(struct TCP_Server_Info *server)
        kfree(server->session_key.response);
        server->session_key.response = NULL;
        server->session_key.len = 0;
+
+       task = xchg(&server->tsk, NULL);
+       if (task)
+               force_sig(SIGKILL, task);
 }
 
 static struct TCP_Server_Info *