dlm: use workqueue for callbacks

Instead of creating our own kthread (dlm_astd) to deliver
callbacks for all lockspaces, use a per-lockspace workqueue
to deliver the callbacks.  This eliminates complications and
slowdowns from many lockspaces sharing the same thread.

Signed-off-by: David Teigland <teigland@redhat.com>

1 files changed, 8 insertions, 1 deletions

diff --git a/fs/dlm/dlm_internal.h b/fs/dlm/dlm_internal.h
index 6614f335e25d..fe2860c02449 100644
--- a/fs/dlm/dlm_internal.h
+++ b/fs/dlm/dlm_internal.h
@@ -246,13 +246,15 @@ struct dlm_lkb {
         struct list_head        lkb_statequeue; /* rsb g/c/w list */
         struct list_head        lkb_rsb_lookup; /* waiting for rsb lookup */
         struct list_head        lkb_wait_reply; /* waiting for remote reply */
-        struct list_head        lkb_astqueue;   /* need ast to be sent */
         struct list_head        lkb_ownqueue;   /* list of locks for a process */
         struct list_head        lkb_time_list;
         ktime_t                 lkb_timestamp;
         ktime_t                 lkb_wait_time;
         unsigned long           lkb_timeout_cs;
 
+        struct mutex            lkb_cb_mutex;
+        struct work_struct      lkb_cb_work;
+        struct list_head        lkb_cb_list; /* for ls_cb_delay or proc->asts */
         struct dlm_callback     lkb_callbacks[DLM_CALLBACKS_SIZE];
         struct dlm_callback     lkb_last_cast;
         struct dlm_callback     lkb_last_bast;
@@ -504,8 +506,12 @@ struct dlm_ls {
 
         struct miscdevice       ls_device;
 
+        struct workqueue_struct *ls_callback_wq;
+
         /* recovery related */
 
+        struct mutex            ls_cb_mutex;
+        struct list_head        ls_cb_delay; /* save for queue_work later */
         struct timer_list       ls_timer;
         struct task_struct      *ls_recoverd_task;
         struct mutex            ls_recoverd_active;
@@ -542,6 +548,7 @@ struct dlm_ls {
 #define LSFL_RCOM_WAIT          4
 #define LSFL_UEVENT_WAIT        5
 #define LSFL_TIMEWARN           6
+#define LSFL_CB_DELAY           7
 
 /* much of this is just saving user space pointers associated with the
    lock that we pass back to the user lib with an ast */