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, 21 insertions, 22 deletions

diff --git a/fs/dlm/lockspace.c b/fs/dlm/lockspace.c
index 98a97762c893..a1d8f1af144b 100644
--- a/fs/dlm/lockspace.c
+++ b/fs/dlm/lockspace.c
@@ -15,7 +15,6 @@
 #include "lockspace.h"
 #include "member.h"
 #include "recoverd.h"
-#include "ast.h"
 #include "dir.h"
 #include "lowcomms.h"
 #include "config.h"
@@ -24,6 +23,7 @@
 #include "recover.h"
 #include "requestqueue.h"
 #include "user.h"
+#include "ast.h"
 
 static int                      ls_count;
 static struct mutex             ls_lock;
@@ -359,17 +359,10 @@ static int threads_start(void)
 {
         int error;
 
-        /* Thread which process lock requests for all lockspace's */
-        error = dlm_astd_start();
-        if (error) {
-                log_print("cannot start dlm_astd thread %d", error);
-                goto fail;
-        }
-
         error = dlm_scand_start();
         if (error) {
                 log_print("cannot start dlm_scand thread %d", error);
-                goto astd_fail;
+                goto fail;
         }
 
         /* Thread for sending/receiving messages for all lockspace's */
@@ -383,8 +376,6 @@ static int threads_start(void)
 
  scand_fail:
         dlm_scand_stop();
- astd_fail:
-        dlm_astd_stop();
  fail:
         return error;
 }
@@ -393,7 +384,6 @@ static void threads_stop(void)
 {
         dlm_scand_stop();
         dlm_lowcomms_stop();
-        dlm_astd_stop();
 }
 
 static int new_lockspace(const char *name, int namelen, void **lockspace,
@@ -514,6 +504,9 @@ static int new_lockspace(const char *name, int namelen, void **lockspace,
         init_completion(&ls->ls_members_done);
         ls->ls_members_result = -1;
 
+        mutex_init(&ls->ls_cb_mutex);
+        INIT_LIST_HEAD(&ls->ls_cb_delay);
+
         ls->ls_recoverd_task = NULL;
         mutex_init(&ls->ls_recoverd_active);
         spin_lock_init(&ls->ls_recover_lock);
@@ -547,18 +540,26 @@ static int new_lockspace(const char *name, int namelen, void **lockspace,
         list_add(&ls->ls_list, &lslist);
         spin_unlock(&lslist_lock);
 
+        if (flags & DLM_LSFL_FS) {
+                error = dlm_callback_start(ls);
+                if (error) {
+                        log_error(ls, "can't start dlm_callback %d", error);
+                        goto out_delist;
+                }
+        }
+
         /* needs to find ls in lslist */
         error = dlm_recoverd_start(ls);
         if (error) {
                 log_error(ls, "can't start dlm_recoverd %d", error);
-                goto out_delist;
+                goto out_callback;
         }
 
         ls->ls_kobj.kset = dlm_kset;
         error = kobject_init_and_add(&ls->ls_kobj, &dlm_ktype, NULL,
                                      "%s", ls->ls_name);
         if (error)
-                goto out_stop;
+                goto out_recoverd;
         kobject_uevent(&ls->ls_kobj, KOBJ_ADD);
 
         /* let kobject handle freeing of ls if there's an error */
@@ -572,7 +573,7 @@ static int new_lockspace(const char *name, int namelen, void **lockspace,
 
         error = do_uevent(ls, 1);
         if (error)
-                goto out_stop;
+                goto out_recoverd;
 
         wait_for_completion(&ls->ls_members_done);
         error = ls->ls_members_result;
@@ -589,8 +590,10 @@ static int new_lockspace(const char *name, int namelen, void **lockspace,
         do_uevent(ls, 0);
         dlm_clear_members(ls);
         kfree(ls->ls_node_array);
- out_stop:
+ out_recoverd:
         dlm_recoverd_stop(ls);
+ out_callback:
+        dlm_callback_stop(ls);
  out_delist:
         spin_lock(&lslist_lock);
         list_del(&ls->ls_list);
@@ -652,8 +655,6 @@ static int lkb_idr_free(int id, void *p, void *data)
 {
         struct dlm_lkb *lkb = p;
 
-        dlm_del_ast(lkb);
-
         if (lkb->lkb_lvbptr && lkb->lkb_flags & DLM_IFL_MSTCPY)
                 dlm_free_lvb(lkb->lkb_lvbptr);
 
@@ -717,12 +718,12 @@ static int release_lockspace(struct dlm_ls *ls, int force)
 
         dlm_recoverd_stop(ls);
 
+        dlm_callback_stop(ls);
+
         remove_lockspace(ls);
 
         dlm_delete_debug_file(ls);
 
-        dlm_astd_suspend();
-
         kfree(ls->ls_recover_buf);
 
         /*
@@ -740,8 +741,6 @@ static int release_lockspace(struct dlm_ls *ls, int force)
         idr_remove_all(&ls->ls_lkbidr);
         idr_destroy(&ls->ls_lkbidr);
 
-        dlm_astd_resume();
-
         /*
          * Free all rsb's on rsbtbl[] lists
          */