xfs: convert log grant ticket queues to list heads
[pandora-kernel.git] / fs / xfs / xfs_log.c
index cee4ab9..1b82735 100644 (file)
@@ -95,38 +95,6 @@ STATIC void  xlog_verify_tail_lsn(xlog_t *log, xlog_in_core_t *iclog,
 
 STATIC int     xlog_iclogs_empty(xlog_t *log);
 
-
-static void
-xlog_ins_ticketq(struct xlog_ticket **qp, struct xlog_ticket *tic)
-{
-       if (*qp) {
-               tic->t_next         = (*qp);
-               tic->t_prev         = (*qp)->t_prev;
-               (*qp)->t_prev->t_next = tic;
-               (*qp)->t_prev       = tic;
-       } else {
-               tic->t_prev = tic->t_next = tic;
-               *qp = tic;
-       }
-
-       tic->t_flags |= XLOG_TIC_IN_Q;
-}
-
-static void
-xlog_del_ticketq(struct xlog_ticket **qp, struct xlog_ticket *tic)
-{
-       if (tic == tic->t_next) {
-               *qp = NULL;
-       } else {
-               *qp = tic->t_next;
-               tic->t_next->t_prev = tic->t_prev;
-               tic->t_prev->t_next = tic->t_next;
-       }
-
-       tic->t_next = tic->t_prev = NULL;
-       tic->t_flags &= ~XLOG_TIC_IN_Q;
-}
-
 static void
 xlog_grant_sub_space(struct log *log, int bytes)
 {
@@ -724,7 +692,7 @@ xfs_log_move_tail(xfs_mount_t       *mp,
                log->l_tail_lsn = tail_lsn;
        }
 
-       if ((tic = log->l_write_headq)) {
+       if (!list_empty(&log->l_writeq)) {
 #ifdef DEBUG
                if (log->l_flags & XLOG_ACTIVE_RECOVERY)
                        panic("Recovery problem");
@@ -732,7 +700,7 @@ xfs_log_move_tail(xfs_mount_t       *mp,
                cycle = log->l_grant_write_cycle;
                bytes = log->l_grant_write_bytes;
                free_bytes = xlog_space_left(log, cycle, bytes);
-               do {
+               list_for_each_entry(tic, &log->l_writeq, t_queue) {
                        ASSERT(tic->t_flags & XLOG_TIC_PERM_RESERV);
 
                        if (free_bytes < tic->t_unit_res && tail_lsn != 1)
@@ -740,10 +708,10 @@ xfs_log_move_tail(xfs_mount_t     *mp,
                        tail_lsn = 0;
                        free_bytes -= tic->t_unit_res;
                        sv_signal(&tic->t_wait);
-                       tic = tic->t_next;
-               } while (tic != log->l_write_headq);
+               }
        }
-       if ((tic = log->l_reserve_headq)) {
+
+       if (!list_empty(&log->l_reserveq)) {
 #ifdef DEBUG
                if (log->l_flags & XLOG_ACTIVE_RECOVERY)
                        panic("Recovery problem");
@@ -751,7 +719,7 @@ xfs_log_move_tail(xfs_mount_t       *mp,
                cycle = log->l_grant_reserve_cycle;
                bytes = log->l_grant_reserve_bytes;
                free_bytes = xlog_space_left(log, cycle, bytes);
-               do {
+               list_for_each_entry(tic, &log->l_reserveq, t_queue) {
                        if (tic->t_flags & XLOG_TIC_PERM_RESERV)
                                need_bytes = tic->t_unit_res*tic->t_cnt;
                        else
@@ -761,8 +729,7 @@ xfs_log_move_tail(xfs_mount_t       *mp,
                        tail_lsn = 0;
                        free_bytes -= need_bytes;
                        sv_signal(&tic->t_wait);
-                       tic = tic->t_next;
-               } while (tic != log->l_reserve_headq);
+               }
        }
        spin_unlock(&log->l_grant_lock);
 }      /* xfs_log_move_tail */
@@ -1053,6 +1020,8 @@ xlog_alloc_log(xfs_mount_t        *mp,
        log->l_curr_cycle  = 1;     /* 0 is bad since this is initial value */
        log->l_grant_reserve_cycle = 1;
        log->l_grant_write_cycle = 1;
+       INIT_LIST_HEAD(&log->l_reserveq);
+       INIT_LIST_HEAD(&log->l_writeq);
 
        error = EFSCORRUPTED;
        if (xfs_sb_version_hassector(&mp->m_sb)) {
@@ -2550,8 +2519,8 @@ xlog_grant_log_space(xlog_t          *log,
        trace_xfs_log_grant_enter(log, tic);
 
        /* something is already sleeping; insert new transaction at end */
-       if (log->l_reserve_headq) {
-               xlog_ins_ticketq(&log->l_reserve_headq, tic);
+       if (!list_empty(&log->l_reserveq)) {
+               list_add_tail(&tic->t_queue, &log->l_reserveq);
 
                trace_xfs_log_grant_sleep1(log, tic);
 
@@ -2583,8 +2552,8 @@ redo:
        free_bytes = xlog_space_left(log, log->l_grant_reserve_cycle,
                                     log->l_grant_reserve_bytes);
        if (free_bytes < need_bytes) {
-               if ((tic->t_flags & XLOG_TIC_IN_Q) == 0)
-                       xlog_ins_ticketq(&log->l_reserve_headq, tic);
+               if (list_empty(&tic->t_queue))
+                       list_add_tail(&tic->t_queue, &log->l_reserveq);
 
                trace_xfs_log_grant_sleep2(log, tic);
 
@@ -2602,8 +2571,9 @@ redo:
                trace_xfs_log_grant_wake2(log, tic);
 
                goto redo;
-       } else if (tic->t_flags & XLOG_TIC_IN_Q)
-               xlog_del_ticketq(&log->l_reserve_headq, tic);
+       }
+
+       list_del_init(&tic->t_queue);
 
        /* we've got enough space */
        xlog_grant_add_space(log, need_bytes);
@@ -2626,9 +2596,7 @@ redo:
        return 0;
 
  error_return:
-       if (tic->t_flags & XLOG_TIC_IN_Q)
-               xlog_del_ticketq(&log->l_reserve_headq, tic);
-
+       list_del_init(&tic->t_queue);
        trace_xfs_log_grant_error(log, tic);
 
        /*
@@ -2653,7 +2621,6 @@ xlog_regrant_write_log_space(xlog_t          *log,
                             xlog_ticket_t *tic)
 {
        int             free_bytes, need_bytes;
-       xlog_ticket_t   *ntic;
 #ifdef DEBUG
        xfs_lsn_t       tail_lsn;
 #endif
@@ -2683,22 +2650,23 @@ xlog_regrant_write_log_space(xlog_t        *log,
         * this transaction.
         */
        need_bytes = tic->t_unit_res;
-       if ((ntic = log->l_write_headq)) {
+       if (!list_empty(&log->l_writeq)) {
+               struct xlog_ticket *ntic;
                free_bytes = xlog_space_left(log, log->l_grant_write_cycle,
                                             log->l_grant_write_bytes);
-               do {
+               list_for_each_entry(ntic, &log->l_writeq, t_queue) {
                        ASSERT(ntic->t_flags & XLOG_TIC_PERM_RESERV);
 
                        if (free_bytes < ntic->t_unit_res)
                                break;
                        free_bytes -= ntic->t_unit_res;
                        sv_signal(&ntic->t_wait);
-                       ntic = ntic->t_next;
-               } while (ntic != log->l_write_headq);
+               }
 
-               if (ntic != log->l_write_headq) {
-                       if ((tic->t_flags & XLOG_TIC_IN_Q) == 0)
-                               xlog_ins_ticketq(&log->l_write_headq, tic);
+               if (ntic != list_first_entry(&log->l_writeq,
+                                               struct xlog_ticket, t_queue)) {
+                       if (list_empty(&tic->t_queue))
+                               list_add_tail(&tic->t_queue, &log->l_writeq);
 
                        trace_xfs_log_regrant_write_sleep1(log, tic);
 
@@ -2727,8 +2695,8 @@ redo:
        free_bytes = xlog_space_left(log, log->l_grant_write_cycle,
                                     log->l_grant_write_bytes);
        if (free_bytes < need_bytes) {
-               if ((tic->t_flags & XLOG_TIC_IN_Q) == 0)
-                       xlog_ins_ticketq(&log->l_write_headq, tic);
+               if (list_empty(&tic->t_queue))
+                       list_add_tail(&tic->t_queue, &log->l_writeq);
                spin_unlock(&log->l_grant_lock);
                xlog_grant_push_ail(log->l_mp, need_bytes);
                spin_lock(&log->l_grant_lock);
@@ -2745,8 +2713,9 @@ redo:
 
                trace_xfs_log_regrant_write_wake2(log, tic);
                goto redo;
-       } else if (tic->t_flags & XLOG_TIC_IN_Q)
-               xlog_del_ticketq(&log->l_write_headq, tic);
+       }
+
+       list_del_init(&tic->t_queue);
 
        /* we've got enough space */
        xlog_grant_add_space_write(log, need_bytes);
@@ -2766,9 +2735,7 @@ redo:
 
 
  error_return:
-       if (tic->t_flags & XLOG_TIC_IN_Q)
-               xlog_del_ticketq(&log->l_reserve_headq, tic);
-
+       list_del_init(&tic->t_queue);
        trace_xfs_log_regrant_write_error(log, tic);
 
        /*
@@ -3435,6 +3402,7 @@ xlog_ticket_alloc(
         }
 
        atomic_set(&tic->t_ref, 1);
+       INIT_LIST_HEAD(&tic->t_queue);
        tic->t_unit_res         = unit_bytes;
        tic->t_curr_res         = unit_bytes;
        tic->t_cnt              = cnt;
@@ -3742,26 +3710,17 @@ xfs_log_force_umount(
        spin_unlock(&log->l_icloglock);
 
        /*
-        * We don't want anybody waiting for log reservations
-        * after this. That means we have to wake up everybody
-        * queued up on reserve_headq as well as write_headq.
-        * In addition, we make sure in xlog_{re}grant_log_space
-        * that we don't enqueue anything once the SHUTDOWN flag
-        * is set, and this action is protected by the GRANTLOCK.
+        * We don't want anybody waiting for log reservations after this. That
+        * means we have to wake up everybody queued up on reserveq as well as
+        * writeq.  In addition, we make sure in xlog_{re}grant_log_space that
+        * we don't enqueue anything once the SHUTDOWN flag is set, and this
+        * action is protected by the GRANTLOCK.
         */
-       if ((tic = log->l_reserve_headq)) {
-               do {
-                       sv_signal(&tic->t_wait);
-                       tic = tic->t_next;
-               } while (tic != log->l_reserve_headq);
-       }
+       list_for_each_entry(tic, &log->l_reserveq, t_queue)
+               sv_signal(&tic->t_wait);
 
-       if ((tic = log->l_write_headq)) {
-               do {
-                       sv_signal(&tic->t_wait);
-                       tic = tic->t_next;
-               } while (tic != log->l_write_headq);
-       }
+       list_for_each_entry(tic, &log->l_writeq, t_queue)
+               sv_signal(&tic->t_wait);
        spin_unlock(&log->l_grant_lock);
 
        if (!(log->l_iclog->ic_state & XLOG_STATE_IOERROR)) {