[PATCH 04/14] xfs: use wait queues directly for log grant queues

[Dave Chinner <david@xxxxxxxxxxxxx>]

From: Dave Chinner <dchinner@xxxxxxxxxx>

The log grant queues are one of the few places left using sv_t
constructs for waiting. Convert them to use wait queues directly
while we are cleaning up the code to move one step closer to remove
the sv_t type from the XFS codebase.

Signed-off-by: Dave Chinner <dchinner@xxxxxxxxxx>
---
 fs/xfs/xfs_log.c      |   32 +++++++++++++++++++++-----------
 fs/xfs/xfs_log_priv.h |    2 +-
 2 files changed, 22 insertions(+), 12 deletions(-)

diff --git a/fs/xfs/xfs_log.c b/fs/xfs/xfs_log.c
index 69a9563..93b5b2d 100644
--- a/fs/xfs/xfs_log.c
+++ b/fs/xfs/xfs_log.c
@@ -739,7 +739,7 @@ xfs_log_move_tail(xfs_mount_t       *mp,
                                break;
                        tail_lsn = 0;
                        free_bytes -= tic->t_unit_res;
-                       sv_signal(&tic->t_wait);
+                       wake_up(&tic->t_wait);
                }
        }
 
@@ -759,7 +759,7 @@ xfs_log_move_tail(xfs_mount_t       *mp,
                                break;
                        tail_lsn = 0;
                        free_bytes -= need_bytes;
-                       sv_signal(&tic->t_wait);
+                       wake_up(&tic->t_wait);
                }
        }
        spin_unlock(&log->l_grant_lock);
@@ -2537,6 +2537,7 @@ xlog_grant_log_space(
 {
        int                      free_bytes;
        int                      need_bytes;
+       DECLARE_WAITQUEUE(wait, current);
 
 #ifdef DEBUG
        if (log->l_flags & XLOG_ACTIVE_RECOVERY)
@@ -2573,7 +2574,12 @@ redo:
 
                XFS_STATS_INC(xs_sleep_logspace);
                trace_xfs_log_grant_sleep(log, tic);
-               sv_wait(&tic->t_wait, PINOD|PLTWAIT, &log->l_grant_lock, s);
+
+               add_wait_queue_exclusive(&tic->t_wait, &wait);
+               __set_current_state(TASK_UNINTERRUPTIBLE);
+               spin_unlock(&log->l_grant_lock);
+               schedule();
+               remove_wait_queue(&tic->t_wait, &wait);
 
                spin_lock(&log->l_grant_lock);
                trace_xfs_log_grant_wake(log, tic);
@@ -2617,6 +2623,7 @@ xlog_regrant_write_log_space(
 {
        int                     free_bytes;
        int                     need_bytes;
+       DECLARE_WAITQUEUE(wait, current);
 
        tic->t_curr_res = tic->t_unit_res;
        xlog_tic_reset_res(tic);
@@ -2662,7 +2669,7 @@ redo:
                                        break;
                                }
                                free_bytes -= ntic->t_unit_res;
-                               sv_signal(&ntic->t_wait);
+                               wake_up(&ntic->t_wait);
                        }
                        list_add_tail(&tic->t_queue, &log->l_writeq);
                        if (woke_all)
@@ -2675,7 +2682,12 @@ redo:
 
                XFS_STATS_INC(xs_sleep_logspace);
                trace_xfs_log_regrant_write_sleep(log, tic);
-               sv_wait(&tic->t_wait, PINOD|PLTWAIT, &log->l_grant_lock, s);
+
+               add_wait_queue_exclusive(&tic->t_wait, &wait);
+               __set_current_state(TASK_UNINTERRUPTIBLE);
+               spin_unlock(&log->l_grant_lock);
+               schedule();
+               remove_wait_queue(&tic->t_wait, &wait);
 
                spin_lock(&log->l_grant_lock);
                trace_xfs_log_regrant_write_wake(log, tic);
@@ -3237,10 +3249,8 @@ xfs_log_ticket_put(
        xlog_ticket_t   *ticket)
 {
        ASSERT(atomic_read(&ticket->t_ref) > 0);
-       if (atomic_dec_and_test(&ticket->t_ref)) {
-               sv_destroy(&ticket->t_wait);
+       if (atomic_dec_and_test(&ticket->t_ref))
                kmem_zone_free(xfs_log_ticket_zone, ticket);
-       }
 }
 
 xlog_ticket_t *
@@ -3373,7 +3383,7 @@ xlog_ticket_alloc(
        tic->t_trans_type       = 0;
        if (xflags & XFS_LOG_PERM_RESERV)
                tic->t_flags |= XLOG_TIC_PERM_RESERV;
-       sv_init(&tic->t_wait, SV_DEFAULT, "logtick");
+       init_waitqueue_head(&tic->t_wait);
 
        xlog_tic_reset_res(tic);
 
@@ -3701,10 +3711,10 @@ xfs_log_force_umount(
         * action is protected by the GRANTLOCK.
         */
        list_for_each_entry(tic, &log->l_reserveq, t_queue)
-               sv_signal(&tic->t_wait);
+               wake_up(&tic->t_wait);
 
        list_for_each_entry(tic, &log->l_writeq, t_queue)
-               sv_signal(&tic->t_wait);
+               wake_up(&tic->t_wait);
        spin_unlock(&log->l_grant_lock);
 
        if (!(log->l_iclog->ic_state & XLOG_STATE_IOERROR)) {
diff --git a/fs/xfs/xfs_log_priv.h b/fs/xfs/xfs_log_priv.h
index 4ebaf07..6fcee10 100644
--- a/fs/xfs/xfs_log_priv.h
+++ b/fs/xfs/xfs_log_priv.h
@@ -242,7 +242,7 @@ typedef struct xlog_res {
 } xlog_res_t;
 
 typedef struct xlog_ticket {
-       sv_t               t_wait;       /* ticket wait queue            : 20 */
+       wait_queue_head_t  t_wait;       /* ticket wait queue */
        struct list_head   t_queue;      /* reserve/write queue */
        xlog_tid_t         t_tid;        /* transaction identifier       : 4  */
        atomic_t           t_ref;        /* ticket reference count       : 4  */
-- 
1.7.2.3