} while (head_val != old);
}
+STATIC bool
+xlog_reserveq_wake(
+ struct log *log,
+ int *free_bytes)
+{
+ struct xlog_ticket *tic;
+ int need_bytes;
+
+ 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
+ need_bytes = tic->t_unit_res;
+
+ if (*free_bytes < need_bytes)
+ return false;
+ *free_bytes -= need_bytes;
+
+ trace_xfs_log_grant_wake_up(log, tic);
+ wake_up(&tic->t_wait);
+ }
+
+ return true;
+}
+
+STATIC bool
+xlog_writeq_wake(
+ struct log *log,
+ int *free_bytes)
+{
+ struct xlog_ticket *tic;
+ int need_bytes;
+
+ list_for_each_entry(tic, &log->l_writeq, t_queue) {
+ ASSERT(tic->t_flags & XLOG_TIC_PERM_RESERV);
+
+ need_bytes = tic->t_unit_res;
+
+ if (*free_bytes < need_bytes)
+ return false;
+ *free_bytes -= need_bytes;
+
+ trace_xfs_log_regrant_write_wake_up(log, tic);
+ wake_up(&tic->t_wait);
+ }
+
+ return true;
+}
+
+STATIC int
+xlog_reserveq_wait(
+ struct log *log,
+ struct xlog_ticket *tic,
+ int need_bytes)
+{
+ list_add_tail(&tic->t_queue, &log->l_reserveq);
+
+ do {
+ if (XLOG_FORCED_SHUTDOWN(log))
+ goto shutdown;
+ xlog_grant_push_ail(log, need_bytes);
+
+ XFS_STATS_INC(xs_sleep_logspace);
+ trace_xfs_log_grant_sleep(log, tic);
+
+ xlog_wait(&tic->t_wait, &log->l_grant_reserve_lock);
+ trace_xfs_log_grant_wake(log, tic);
+
+ spin_lock(&log->l_grant_reserve_lock);
+ if (XLOG_FORCED_SHUTDOWN(log))
+ goto shutdown;
+ } while (xlog_space_left(log, &log->l_grant_reserve_head) < need_bytes);
+
+ list_del_init(&tic->t_queue);
+ return 0;
+shutdown:
+ list_del_init(&tic->t_queue);
+ return XFS_ERROR(EIO);
+}
+
+STATIC int
+xlog_writeq_wait(
+ struct log *log,
+ struct xlog_ticket *tic,
+ int need_bytes)
+{
+ list_add_tail(&tic->t_queue, &log->l_writeq);
+
+ do {
+ if (XLOG_FORCED_SHUTDOWN(log))
+ goto shutdown;
+ xlog_grant_push_ail(log, need_bytes);
+
+ XFS_STATS_INC(xs_sleep_logspace);
+ trace_xfs_log_regrant_write_sleep(log, tic);
+
+ xlog_wait(&tic->t_wait, &log->l_grant_write_lock);
+ trace_xfs_log_regrant_write_wake(log, tic);
+
+ spin_lock(&log->l_grant_write_lock);
+ if (XLOG_FORCED_SHUTDOWN(log))
+ goto shutdown;
+ } while (xlog_space_left(log, &log->l_grant_write_head) < need_bytes);
+
+ list_del_init(&tic->t_queue);
+ return 0;
+shutdown:
+ list_del_init(&tic->t_queue);
+ return XFS_ERROR(EIO);
+}
+
static void
xlog_tic_reset_res(xlog_ticket_t *tic)
{
retval = xlog_grant_log_space(log, internal_ticket);
}
+ if (unlikely(retval)) {
+ /*
+ * If we are failing, make sure the ticket doesn't have any
+ * current reservations. We don't want to add this back
+ * when the ticket/ transaction gets cancelled.
+ */
+ internal_ticket->t_curr_res = 0;
+ /* ungrant will give back unit_res * t_cnt. */
+ internal_ticket->t_cnt = 0;
+ }
+
return retval;
-} /* xfs_log_reserve */
+}
/*
/*
* Atomically get the log space required for a log ticket.
*
- * Once a ticket gets put onto the reserveq, it will only return after
- * the needed reservation is satisfied.
+ * Once a ticket gets put onto the reserveq, it will only return after the
+ * needed reservation is satisfied.
*
* This function is structured so that it has a lock free fast path. This is
* necessary because every new transaction reservation will come through this
* every pass.
*
* As tickets are only ever moved on and off the reserveq under the
- * l_grant_reserve_lock, we only need to take that lock if we are going
- * to add the ticket to the queue and sleep. We can avoid taking the lock if the
- * ticket was never added to the reserveq because the t_queue list head will be
- * empty and we hold the only reference to it so it can safely be checked
- * unlocked.
+ * l_grant_reserve_lock, we only need to take that lock if we are going to add
+ * the ticket to the queue and sleep. We can avoid taking the lock if the ticket
+ * was never added to the reserveq because the t_queue list head will be empty
+ * and we hold the only reference to it so it can safely be checked unlocked.
*/
STATIC int
-xlog_grant_log_space(xlog_t *log,
- xlog_ticket_t *tic)
+xlog_grant_log_space(
+ struct log *log,
+ struct xlog_ticket *tic)
{
- int free_bytes;
- int need_bytes;
+ int free_bytes, need_bytes;
+ int error = 0;
-#ifdef DEBUG
- if (log->l_flags & XLOG_ACTIVE_RECOVERY)
- panic("grant Recovery problem");
-#endif
+ ASSERT(!(log->l_flags & XLOG_ACTIVE_RECOVERY));
trace_xfs_log_grant_enter(log, tic);
+ /*
+ * If there are other waiters on the queue then give them a chance at
+ * logspace before us. Wake up the first waiters, if we do not wake
+ * up all the waiters then go to sleep waiting for more free space,
+ * otherwise try to get some space for this transaction.
+ */
need_bytes = tic->t_unit_res;
if (tic->t_flags & XFS_LOG_PERM_RESERV)
need_bytes *= tic->t_ocnt;
-
- /* something is already sleeping; insert new transaction at end */
- if (!list_empty_careful(&log->l_reserveq)) {
- spin_lock(&log->l_grant_reserve_lock);
- /* recheck the queue now we are locked */
- if (list_empty(&log->l_reserveq)) {
- spin_unlock(&log->l_grant_reserve_lock);
- goto redo;
- }
- list_add_tail(&tic->t_queue, &log->l_reserveq);
-
- trace_xfs_log_grant_sleep1(log, tic);
-
- /*
- * Gotta check this before going to sleep, while we're
- * holding the grant lock.
- */
- if (XLOG_FORCED_SHUTDOWN(log))
- goto error_return;
-
- XFS_STATS_INC(xs_sleep_logspace);
- xlog_wait(&tic->t_wait, &log->l_grant_reserve_lock);
-
- /*
- * If we got an error, and the filesystem is shutting down,
- * we'll catch it down below. So just continue...
- */
- trace_xfs_log_grant_wake1(log, tic);
- }
-
-redo:
- if (XLOG_FORCED_SHUTDOWN(log))
- goto error_return_unlocked;
-
free_bytes = xlog_space_left(log, &log->l_grant_reserve_head);
- if (free_bytes < need_bytes) {
+ if (!list_empty_careful(&log->l_reserveq)) {
spin_lock(&log->l_grant_reserve_lock);
- if (list_empty(&tic->t_queue))
- list_add_tail(&tic->t_queue, &log->l_reserveq);
-
- trace_xfs_log_grant_sleep2(log, tic);
-
- if (XLOG_FORCED_SHUTDOWN(log))
- goto error_return;
-
- xlog_grant_push_ail(log, need_bytes);
-
- XFS_STATS_INC(xs_sleep_logspace);
- xlog_wait(&tic->t_wait, &log->l_grant_reserve_lock);
-
- trace_xfs_log_grant_wake2(log, tic);
- goto redo;
- }
-
- if (!list_empty(&tic->t_queue)) {
+ if (!xlog_reserveq_wake(log, &free_bytes) ||
+ free_bytes < need_bytes)
+ error = xlog_reserveq_wait(log, tic, need_bytes);
+ spin_unlock(&log->l_grant_reserve_lock);
+ } else if (free_bytes < need_bytes) {
spin_lock(&log->l_grant_reserve_lock);
- list_del_init(&tic->t_queue);
+ error = xlog_reserveq_wait(log, tic, need_bytes);
spin_unlock(&log->l_grant_reserve_lock);
}
+ if (error)
+ return error;
- /* we've got enough space */
xlog_grant_add_space(log, &log->l_grant_reserve_head, need_bytes);
xlog_grant_add_space(log, &log->l_grant_write_head, need_bytes);
trace_xfs_log_grant_exit(log, tic);
xlog_verify_grant_tail(log);
return 0;
-
-error_return_unlocked:
- spin_lock(&log->l_grant_reserve_lock);
-error_return:
- list_del_init(&tic->t_queue);
- spin_unlock(&log->l_grant_reserve_lock);
- trace_xfs_log_grant_error(log, tic);
-
- /*
- * If we are failing, make sure the ticket doesn't have any
- * current reservations. We don't want to add this back when
- * the ticket/transaction gets cancelled.
- */
- tic->t_curr_res = 0;
- tic->t_cnt = 0; /* ungrant will give back unit_res * t_cnt. */
- return XFS_ERROR(EIO);
-} /* xlog_grant_log_space */
-
+}
/*
* Replenish the byte reservation required by moving the grant write head.
* free fast path.
*/
STATIC int
-xlog_regrant_write_log_space(xlog_t *log,
- xlog_ticket_t *tic)
+xlog_regrant_write_log_space(
+ struct log *log,
+ struct xlog_ticket *tic)
{
- int free_bytes, need_bytes;
+ int free_bytes, need_bytes;
+ int error = 0;
tic->t_curr_res = tic->t_unit_res;
xlog_tic_reset_res(tic);
if (tic->t_cnt > 0)
return 0;
-#ifdef DEBUG
- if (log->l_flags & XLOG_ACTIVE_RECOVERY)
- panic("regrant Recovery problem");
-#endif
+ ASSERT(!(log->l_flags & XLOG_ACTIVE_RECOVERY));
trace_xfs_log_regrant_write_enter(log, tic);
- if (XLOG_FORCED_SHUTDOWN(log))
- goto error_return_unlocked;
- /* If there are other waiters on the queue then give them a
- * chance at logspace before us. Wake up the first waiters,
- * if we do not wake up all the waiters then go to sleep waiting
- * for more free space, otherwise try to get some space for
- * this transaction.
+ /*
+ * If there are other waiters on the queue then give them a chance at
+ * logspace before us. Wake up the first waiters, if we do not wake
+ * up all the waiters then go to sleep waiting for more free space,
+ * otherwise try to get some space for this transaction.
*/
need_bytes = tic->t_unit_res;
- if (!list_empty_careful(&log->l_writeq)) {
- struct xlog_ticket *ntic;
-
- spin_lock(&log->l_grant_write_lock);
- free_bytes = xlog_space_left(log, &log->l_grant_write_head);
- 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;
- wake_up(&ntic->t_wait);
- }
-
- 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);
-
- xlog_grant_push_ail(log, need_bytes);
-
- XFS_STATS_INC(xs_sleep_logspace);
- xlog_wait(&tic->t_wait, &log->l_grant_write_lock);
- trace_xfs_log_regrant_write_wake1(log, tic);
- } else
- spin_unlock(&log->l_grant_write_lock);
- }
-
-redo:
- if (XLOG_FORCED_SHUTDOWN(log))
- goto error_return_unlocked;
-
free_bytes = xlog_space_left(log, &log->l_grant_write_head);
- if (free_bytes < need_bytes) {
+ if (!list_empty_careful(&log->l_writeq)) {
spin_lock(&log->l_grant_write_lock);
- if (list_empty(&tic->t_queue))
- list_add_tail(&tic->t_queue, &log->l_writeq);
-
- if (XLOG_FORCED_SHUTDOWN(log))
- goto error_return;
-
- xlog_grant_push_ail(log, need_bytes);
-
- XFS_STATS_INC(xs_sleep_logspace);
- trace_xfs_log_regrant_write_sleep2(log, tic);
- xlog_wait(&tic->t_wait, &log->l_grant_write_lock);
-
- trace_xfs_log_regrant_write_wake2(log, tic);
- goto redo;
- }
-
- if (!list_empty(&tic->t_queue)) {
+ if (!xlog_writeq_wake(log, &free_bytes) ||
+ free_bytes < need_bytes)
+ error = xlog_writeq_wait(log, tic, need_bytes);
+ spin_unlock(&log->l_grant_write_lock);
+ } else if (free_bytes < need_bytes) {
spin_lock(&log->l_grant_write_lock);
- list_del_init(&tic->t_queue);
+ error = xlog_writeq_wait(log, tic, need_bytes);
spin_unlock(&log->l_grant_write_lock);
}
- /* we've got enough space */
+ if (error)
+ return error;
+
xlog_grant_add_space(log, &log->l_grant_write_head, need_bytes);
trace_xfs_log_regrant_write_exit(log, tic);
xlog_verify_grant_tail(log);
return 0;
-
-
- error_return_unlocked:
- spin_lock(&log->l_grant_write_lock);
- error_return:
- list_del_init(&tic->t_queue);
- spin_unlock(&log->l_grant_write_lock);
- trace_xfs_log_regrant_write_error(log, tic);
-
- /*
- * If we are failing, make sure the ticket doesn't have any
- * current reservations. We don't want to add this back when
- * the ticket/transaction gets cancelled.
- */
- tic->t_curr_res = 0;
- tic->t_cnt = 0; /* ungrant will give back unit_res * t_cnt. */
- return XFS_ERROR(EIO);
-} /* xlog_regrant_write_log_space */
-
+}
/* The first cnt-1 times through here we don't need to
* move the grant write head because the permanent