CIFS: Cleanup demupltiplex thread exiting code

Reviewed-and-Tested-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Pavel Shilovsky <piastryyy@gmail.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>

1 files changed, 96 insertions, 77 deletions

diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index 12b2741ef8f..80c2e3add3a 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -531,6 +531,101 @@ multi_t2_fnd:
         return ret;
 }
 
+static void clean_demultiplex_info(struct TCP_Server_Info *server)
+{
+        int length;
+
+        /* take it off the list, if it's not already */
+        spin_lock(&cifs_tcp_ses_lock);
+        list_del_init(&server->tcp_ses_list);
+        spin_unlock(&cifs_tcp_ses_lock);
+
+        spin_lock(&GlobalMid_Lock);
+        server->tcpStatus = CifsExiting;
+        spin_unlock(&GlobalMid_Lock);
+        wake_up_all(&server->response_q);
+
+        /*
+         * Check if we have blocked requests that need to free. Note that
+         * cifs_max_pending is normally 50, but can be set at module install
+         * time to as little as two.
+         */
+        spin_lock(&GlobalMid_Lock);
+        if (atomic_read(&server->inFlight) >= cifs_max_pending)
+                atomic_set(&server->inFlight, cifs_max_pending - 1);
+        /*
+         * We do not want to set the max_pending too low or we could end up
+         * with the counter going negative.
+         */
+        spin_unlock(&GlobalMid_Lock);
+        /*
+         * Although there should not be any requests blocked on this queue it
+         * can not hurt to be paranoid and try to wake up requests that may
+         * haven been blocked when more than 50 at time were on the wire to the
+         * same server - they now will see the session is in exit state and get
+         * out of SendReceive.
+         */
+        wake_up_all(&server->request_q);
+        /* give those requests time to exit */
+        msleep(125);
+
+        if (server->ssocket) {
+                sock_release(server->ssocket);
+                server->ssocket = NULL;
+        }
+
+        if (!list_empty(&server->pending_mid_q)) {
+                struct list_head dispose_list;
+                struct mid_q_entry *mid_entry;
+                struct list_head *tmp, *tmp2;
+
+                INIT_LIST_HEAD(&dispose_list);
+                spin_lock(&GlobalMid_Lock);
+                list_for_each_safe(tmp, tmp2, &server->pending_mid_q) {
+                        mid_entry = list_entry(tmp, struct mid_q_entry, qhead);
+                        cFYI(1, "Clearing mid 0x%x", mid_entry->mid);
+                        mid_entry->midState = MID_SHUTDOWN;
+                        list_move(&mid_entry->qhead, &dispose_list);
+                }
+                spin_unlock(&GlobalMid_Lock);
+
+                /* now walk dispose list and issue callbacks */
+                list_for_each_safe(tmp, tmp2, &dispose_list) {
+                        mid_entry = list_entry(tmp, struct mid_q_entry, qhead);
+                        cFYI(1, "Callback mid 0x%x", mid_entry->mid);
+                        list_del_init(&mid_entry->qhead);
+                        mid_entry->callback(mid_entry);
+                }
+                /* 1/8th of sec is more than enough time for them to exit */
+                msleep(125);
+        }
+
+        if (!list_empty(&server->pending_mid_q)) {
+                /*
+                 * mpx threads have not exited yet give them at least the smb
+                 * send timeout time for long ops.
+                 *
+                 * Due to delays on oplock break requests, we need to wait at
+                 * least 45 seconds before giving up on a request getting a
+                 * response and going ahead and killing cifsd.
+                 */
+                cFYI(1, "Wait for exit from demultiplex thread");
+                msleep(46000);
+                /*
+                 * If threads still have not exited they are probably never
+                 * coming home not much else we can do but free the memory.
+                 */
+        }
+
+        kfree(server->hostname);
+        kfree(server);
+
+        length = atomic_dec_return(&tcpSesAllocCount);
+        if (length > 0)
+                mempool_resize(cifs_req_poolp, length + cifs_min_rcv,
+                                GFP_KERNEL);
+}
+
 static int
 cifs_demultiplex_thread(void *p)
 {
@@ -541,7 +636,6 @@ cifs_demultiplex_thread(void *p)
         struct smb_hdr *smb_buffer = NULL;
         struct msghdr smb_msg;
         struct kvec iov;
-        struct list_head *tmp, *tmp2;
         struct task_struct *task_to_wake = NULL;
         struct mid_q_entry *mid_entry;
         bool isLargeBuf = false;
@@ -678,88 +772,13 @@ incomplete_rcv:
                 }
         } /* end while !EXITING */
 
-        /* take it off the list, if it's not already */
-        spin_lock(&cifs_tcp_ses_lock);
-        list_del_init(&server->tcp_ses_list);
-        spin_unlock(&cifs_tcp_ses_lock);
-
-        spin_lock(&GlobalMid_Lock);
-        server->tcpStatus = CifsExiting;
-        spin_unlock(&GlobalMid_Lock);
-        wake_up_all(&server->response_q);
-
-        /* check if we have blocked requests that need to free */
-        /* Note that cifs_max_pending is normally 50, but
-        can be set at module install time to as little as two */
-        spin_lock(&GlobalMid_Lock);
-        if (atomic_read(&server->inFlight) >= cifs_max_pending)
-                atomic_set(&server->inFlight, cifs_max_pending - 1);
-        /* We do not want to set the max_pending too low or we
-        could end up with the counter going negative */
-        spin_unlock(&GlobalMid_Lock);
-        /* Although there should not be any requests blocked on
-        this queue it can not hurt to be paranoid and try to wake up requests
-        that may haven been blocked when more than 50 at time were on the wire
-        to the same server - they now will see the session is in exit state
-        and get out of SendReceive.  */
-        wake_up_all(&server->request_q);
-        /* give those requests time to exit */
-        msleep(125);
-
-        if (server->ssocket) {
-                sock_release(server->ssocket);
-                server->ssocket = NULL;
-        }
         /* buffer usually freed in free_mid - need to free it here on exit */
         cifs_buf_release(bigbuf);
         if (smallbuf) /* no sense logging a debug message if NULL */
                 cifs_small_buf_release(smallbuf);
 
-        if (!list_empty(&server->pending_mid_q)) {
-                struct list_head dispose_list;
-
-                INIT_LIST_HEAD(&dispose_list);
-                spin_lock(&GlobalMid_Lock);
-                list_for_each_safe(tmp, tmp2, &server->pending_mid_q) {
-                        mid_entry = list_entry(tmp, struct mid_q_entry, qhead);
-                        cFYI(1, "Clearing mid 0x%x", mid_entry->mid);
-                        mid_entry->midState = MID_SHUTDOWN;
-                        list_move(&mid_entry->qhead, &dispose_list);
-                }
-                spin_unlock(&GlobalMid_Lock);
-
-                /* now walk dispose list and issue callbacks */
-                list_for_each_safe(tmp, tmp2, &dispose_list) {
-                        mid_entry = list_entry(tmp, struct mid_q_entry, qhead);
-                        cFYI(1, "Callback mid 0x%x", mid_entry->mid);
-                        list_del_init(&mid_entry->qhead);
-                        mid_entry->callback(mid_entry);
-                }
-                /* 1/8th of sec is more than enough time for them to exit */
-                msleep(125);
-        }
-
-        if (!list_empty(&server->pending_mid_q)) {
-                /* mpx threads have not exited yet give them
-                at least the smb send timeout time for long ops */
-                /* due to delays on oplock break requests, we need
-                to wait at least 45 seconds before giving up
-                on a request getting a response and going ahead
-                and killing cifsd */
-                cFYI(1, "Wait for exit from demultiplex thread");
-                msleep(46000);
-                /* if threads still have not exited they are probably never
-                coming home not much else we can do but free the memory */
-        }
-
-        kfree(server->hostname);
         task_to_wake = xchg(&server->tsk, NULL);
-        kfree(server);
-
-        length = atomic_dec_return(&tcpSesAllocCount);
-        if (length  > 0)
-                mempool_resize(cifs_req_poolp, length + cifs_min_rcv,
-                                GFP_KERNEL);
+        clean_demultiplex_info(server);
 
         /* if server->tsk was NULL then wait for a signal before exiting */
         if (!task_to_wake) {