fs: dlm: convert ls_cb_mutex mutex to spinlock

This patch converts the ls_cb_mutex mutex to a spinlock, there is no
sleepable context when this lock is held.

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

diff --git a/fs/dlm/ast.c b/fs/dlm/ast.c
index 6e07c15..daaa0df 100644 (file)
--- a/fs/dlm/ast.c
+++ b/fs/dlm/ast.c
@@ -200,13 +200,13 @@ void dlm_add_cb(struct dlm_lkb *lkb, uint32_t flags, int mode, int status,
        if (!prev_seq) {
                kref_get(&lkb->lkb_ref);
 
-               mutex_lock(&ls->ls_cb_mutex);
+               spin_lock(&ls->ls_cb_lock);
                if (test_bit(LSFL_CB_DELAY, &ls->ls_flags)) {
                        list_add(&lkb->lkb_cb_list, &ls->ls_cb_delay);
                } else {
                        queue_work(ls->ls_callback_wq, &lkb->lkb_cb_work);
                }
-               mutex_unlock(&ls->ls_cb_mutex);
+               spin_unlock(&ls->ls_cb_lock);
        }
  out:
        mutex_unlock(&lkb->lkb_cb_mutex);
@@ -289,9 +289,9 @@ void dlm_callback_stop(struct dlm_ls *ls)
 void dlm_callback_suspend(struct dlm_ls *ls)
 {
        if (ls->ls_callback_wq) {
-               mutex_lock(&ls->ls_cb_mutex);
+               spin_lock(&ls->ls_cb_lock);
                set_bit(LSFL_CB_DELAY, &ls->ls_flags);
-               mutex_unlock(&ls->ls_cb_mutex);
+               spin_unlock(&ls->ls_cb_lock);
 
                flush_workqueue(ls->ls_callback_wq);
        }
@@ -309,7 +309,7 @@ void dlm_callback_resume(struct dlm_ls *ls)
                return;
 
 more:
-       mutex_lock(&ls->ls_cb_mutex);
+       spin_lock(&ls->ls_cb_lock);
        list_for_each_entry_safe(lkb, safe, &ls->ls_cb_delay, lkb_cb_list) {
                list_del_init(&lkb->lkb_cb_list);
                queue_work(ls->ls_callback_wq, &lkb->lkb_cb_work);
@@ -320,7 +320,7 @@ more:
        empty = list_empty(&ls->ls_cb_delay);
        if (empty)
                clear_bit(LSFL_CB_DELAY, &ls->ls_flags);
-       mutex_unlock(&ls->ls_cb_mutex);
+       spin_unlock(&ls->ls_cb_lock);
 
        sum += count;
        if (!empty) {

diff --git a/fs/dlm/dlm_internal.h b/fs/dlm/dlm_internal.h
index 94fadb6..fc4be8c 100644 (file)
--- a/fs/dlm/dlm_internal.h
+++ b/fs/dlm/dlm_internal.h
@@ -631,7 +631,7 @@ struct dlm_ls {
 
        /* recovery related */
 
-       struct mutex            ls_cb_mutex;
+       spinlock_t              ls_cb_lock;
        struct list_head        ls_cb_delay; /* save for queue_work later */
        struct timer_list       ls_timer;
        struct task_struct      *ls_recoverd_task;

diff --git a/fs/dlm/lockspace.c b/fs/dlm/lockspace.c
index 9479c81..4965737 100644 (file)
--- a/fs/dlm/lockspace.c
+++ b/fs/dlm/lockspace.c
@@ -567,7 +567,7 @@ static int new_lockspace(const char *name, const char *cluster,
        init_completion(&ls->ls_recovery_done);
        ls->ls_recovery_result = -1;
 
-       mutex_init(&ls->ls_cb_mutex);
+       spin_lock_init(&ls->ls_cb_lock);
        INIT_LIST_HEAD(&ls->ls_cb_delay);
 
        ls->ls_recoverd_task = NULL;