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Diffstat (limited to 'fs/xfs/xfs_log.c')
-rw-r--r--fs/xfs/xfs_log.c739
1 files changed, 335 insertions, 404 deletions
diff --git a/fs/xfs/xfs_log.c b/fs/xfs/xfs_log.c
index cee4ab9f8a9e..0bf24b11d0c4 100644
--- a/fs/xfs/xfs_log.c
+++ b/fs/xfs/xfs_log.c
@@ -47,7 +47,7 @@ STATIC xlog_t * xlog_alloc_log(xfs_mount_t *mp,
xfs_buftarg_t *log_target,
xfs_daddr_t blk_offset,
int num_bblks);
-STATIC int xlog_space_left(xlog_t *log, int cycle, int bytes);
+STATIC int xlog_space_left(struct log *log, atomic64_t *head);
STATIC int xlog_sync(xlog_t *log, xlog_in_core_t *iclog);
STATIC void xlog_dealloc_log(xlog_t *log);
@@ -70,7 +70,7 @@ STATIC void xlog_state_want_sync(xlog_t *log, xlog_in_core_t *iclog);
/* local functions to manipulate grant head */
STATIC int xlog_grant_log_space(xlog_t *log,
xlog_ticket_t *xtic);
-STATIC void xlog_grant_push_ail(xfs_mount_t *mp,
+STATIC void xlog_grant_push_ail(struct log *log,
int need_bytes);
STATIC void xlog_regrant_reserve_log_space(xlog_t *log,
xlog_ticket_t *ticket);
@@ -81,98 +81,73 @@ STATIC void xlog_ungrant_log_space(xlog_t *log,
#if defined(DEBUG)
STATIC void xlog_verify_dest_ptr(xlog_t *log, char *ptr);
-STATIC void xlog_verify_grant_head(xlog_t *log, int equals);
+STATIC void xlog_verify_grant_tail(struct log *log);
STATIC void xlog_verify_iclog(xlog_t *log, xlog_in_core_t *iclog,
int count, boolean_t syncing);
STATIC void xlog_verify_tail_lsn(xlog_t *log, xlog_in_core_t *iclog,
xfs_lsn_t tail_lsn);
#else
#define xlog_verify_dest_ptr(a,b)
-#define xlog_verify_grant_head(a,b)
+#define xlog_verify_grant_tail(a)
#define xlog_verify_iclog(a,b,c,d)
#define xlog_verify_tail_lsn(a,b,c)
#endif
STATIC int xlog_iclogs_empty(xlog_t *log);
-
static void
-xlog_ins_ticketq(struct xlog_ticket **qp, struct xlog_ticket *tic)
+xlog_grant_sub_space(
+ struct log *log,
+ atomic64_t *head,
+ int bytes)
{
- 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;
- }
+ int64_t head_val = atomic64_read(head);
+ int64_t new, old;
- tic->t_flags |= XLOG_TIC_IN_Q;
-}
+ do {
+ int cycle, space;
-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;
- }
+ xlog_crack_grant_head_val(head_val, &cycle, &space);
- tic->t_next = tic->t_prev = NULL;
- tic->t_flags &= ~XLOG_TIC_IN_Q;
+ space -= bytes;
+ if (space < 0) {
+ space += log->l_logsize;
+ cycle--;
+ }
+
+ old = head_val;
+ new = xlog_assign_grant_head_val(cycle, space);
+ head_val = atomic64_cmpxchg(head, old, new);
+ } while (head_val != old);
}
static void
-xlog_grant_sub_space(struct log *log, int bytes)
+xlog_grant_add_space(
+ struct log *log,
+ atomic64_t *head,
+ int bytes)
{
- log->l_grant_write_bytes -= bytes;
- if (log->l_grant_write_bytes < 0) {
- log->l_grant_write_bytes += log->l_logsize;
- log->l_grant_write_cycle--;
- }
-
- log->l_grant_reserve_bytes -= bytes;
- if ((log)->l_grant_reserve_bytes < 0) {
- log->l_grant_reserve_bytes += log->l_logsize;
- log->l_grant_reserve_cycle--;
- }
+ int64_t head_val = atomic64_read(head);
+ int64_t new, old;
-}
+ do {
+ int tmp;
+ int cycle, space;
-static void
-xlog_grant_add_space_write(struct log *log, int bytes)
-{
- int tmp = log->l_logsize - log->l_grant_write_bytes;
- if (tmp > bytes)
- log->l_grant_write_bytes += bytes;
- else {
- log->l_grant_write_cycle++;
- log->l_grant_write_bytes = bytes - tmp;
- }
-}
+ xlog_crack_grant_head_val(head_val, &cycle, &space);
-static void
-xlog_grant_add_space_reserve(struct log *log, int bytes)
-{
- int tmp = log->l_logsize - log->l_grant_reserve_bytes;
- if (tmp > bytes)
- log->l_grant_reserve_bytes += bytes;
- else {
- log->l_grant_reserve_cycle++;
- log->l_grant_reserve_bytes = bytes - tmp;
- }
-}
+ tmp = log->l_logsize - space;
+ if (tmp > bytes)
+ space += bytes;
+ else {
+ space = bytes - tmp;
+ cycle++;
+ }
-static inline void
-xlog_grant_add_space(struct log *log, int bytes)
-{
- xlog_grant_add_space_write(log, bytes);
- xlog_grant_add_space_reserve(log, bytes);
+ old = head_val;
+ new = xlog_assign_grant_head_val(cycle, space);
+ head_val = atomic64_cmpxchg(head, old, new);
+ } while (head_val != old);
}
static void
@@ -355,7 +330,7 @@ xfs_log_reserve(
trace_xfs_log_reserve(log, internal_ticket);
- xlog_grant_push_ail(mp, internal_ticket->t_unit_res);
+ xlog_grant_push_ail(log, internal_ticket->t_unit_res);
retval = xlog_regrant_write_log_space(log, internal_ticket);
} else {
/* may sleep if need to allocate more tickets */
@@ -369,7 +344,7 @@ xfs_log_reserve(
trace_xfs_log_reserve(log, internal_ticket);
- xlog_grant_push_ail(mp,
+ xlog_grant_push_ail(log,
(internal_ticket->t_unit_res *
internal_ticket->t_cnt));
retval = xlog_grant_log_space(log, internal_ticket);
@@ -584,8 +559,8 @@ xfs_log_unmount_write(xfs_mount_t *mp)
if (!(iclog->ic_state == XLOG_STATE_ACTIVE ||
iclog->ic_state == XLOG_STATE_DIRTY)) {
if (!XLOG_FORCED_SHUTDOWN(log)) {
- sv_wait(&iclog->ic_force_wait, PMEM,
- &log->l_icloglock, s);
+ xlog_wait(&iclog->ic_force_wait,
+ &log->l_icloglock);
} else {
spin_unlock(&log->l_icloglock);
}
@@ -625,8 +600,8 @@ xfs_log_unmount_write(xfs_mount_t *mp)
|| iclog->ic_state == XLOG_STATE_DIRTY
|| iclog->ic_state == XLOG_STATE_IOERROR) ) {
- sv_wait(&iclog->ic_force_wait, PMEM,
- &log->l_icloglock, s);
+ xlog_wait(&iclog->ic_force_wait,
+ &log->l_icloglock);
} else {
spin_unlock(&log->l_icloglock);
}
@@ -703,55 +678,46 @@ xfs_log_move_tail(xfs_mount_t *mp,
{
xlog_ticket_t *tic;
xlog_t *log = mp->m_log;
- int need_bytes, free_bytes, cycle, bytes;
+ int need_bytes, free_bytes;
if (XLOG_FORCED_SHUTDOWN(log))
return;
- if (tail_lsn == 0) {
- /* needed since sync_lsn is 64 bits */
- spin_lock(&log->l_icloglock);
- tail_lsn = log->l_last_sync_lsn;
- spin_unlock(&log->l_icloglock);
- }
-
- spin_lock(&log->l_grant_lock);
+ if (tail_lsn == 0)
+ tail_lsn = atomic64_read(&log->l_last_sync_lsn);
- /* Also an invalid lsn. 1 implies that we aren't passing in a valid
- * tail_lsn.
- */
- if (tail_lsn != 1) {
- log->l_tail_lsn = tail_lsn;
- }
+ /* tail_lsn == 1 implies that we weren't passed a valid value. */
+ if (tail_lsn != 1)
+ atomic64_set(&log->l_tail_lsn, tail_lsn);
- if ((tic = log->l_write_headq)) {
+ if (!list_empty_careful(&log->l_writeq)) {
#ifdef DEBUG
if (log->l_flags & XLOG_ACTIVE_RECOVERY)
panic("Recovery problem");
#endif
- cycle = log->l_grant_write_cycle;
- bytes = log->l_grant_write_bytes;
- free_bytes = xlog_space_left(log, cycle, bytes);
- do {
+ spin_lock(&log->l_grant_write_lock);
+ free_bytes = xlog_space_left(log, &log->l_grant_write_head);
+ 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)
break;
tail_lsn = 0;
free_bytes -= tic->t_unit_res;
- sv_signal(&tic->t_wait);
- tic = tic->t_next;
- } while (tic != log->l_write_headq);
+ trace_xfs_log_regrant_write_wake_up(log, tic);
+ wake_up(&tic->t_wait);
+ }
+ spin_unlock(&log->l_grant_write_lock);
}
- if ((tic = log->l_reserve_headq)) {
+
+ if (!list_empty_careful(&log->l_reserveq)) {
#ifdef DEBUG
if (log->l_flags & XLOG_ACTIVE_RECOVERY)
panic("Recovery problem");
#endif
- cycle = log->l_grant_reserve_cycle;
- bytes = log->l_grant_reserve_bytes;
- free_bytes = xlog_space_left(log, cycle, bytes);
- do {
+ spin_lock(&log->l_grant_reserve_lock);
+ free_bytes = xlog_space_left(log, &log->l_grant_reserve_head);
+ 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
@@ -760,12 +726,12 @@ xfs_log_move_tail(xfs_mount_t *mp,
break;
tail_lsn = 0;
free_bytes -= need_bytes;
- sv_signal(&tic->t_wait);
- tic = tic->t_next;
- } while (tic != log->l_reserve_headq);
+ trace_xfs_log_grant_wake_up(log, tic);
+ wake_up(&tic->t_wait);
+ }
+ spin_unlock(&log->l_grant_reserve_lock);
}
- spin_unlock(&log->l_grant_lock);
-} /* xfs_log_move_tail */
+}
/*
* Determine if we have a transaction that has gone to disk
@@ -831,23 +797,19 @@ xfs_log_need_covered(xfs_mount_t *mp)
* We may be holding the log iclog lock upon entering this routine.
*/
xfs_lsn_t
-xlog_assign_tail_lsn(xfs_mount_t *mp)
+xlog_assign_tail_lsn(
+ struct xfs_mount *mp)
{
- xfs_lsn_t tail_lsn;
- xlog_t *log = mp->m_log;
+ xfs_lsn_t tail_lsn;
+ struct log *log = mp->m_log;
tail_lsn = xfs_trans_ail_tail(mp->m_ail);
- spin_lock(&log->l_grant_lock);
- if (tail_lsn != 0) {
- log->l_tail_lsn = tail_lsn;
- } else {
- tail_lsn = log->l_tail_lsn = log->l_last_sync_lsn;
- }
- spin_unlock(&log->l_grant_lock);
+ if (!tail_lsn)
+ tail_lsn = atomic64_read(&log->l_last_sync_lsn);
+ atomic64_set(&log->l_tail_lsn, tail_lsn);
return tail_lsn;
-} /* xlog_assign_tail_lsn */
-
+}
/*
* Return the space in the log between the tail and the head. The head
@@ -864,21 +826,26 @@ xlog_assign_tail_lsn(xfs_mount_t *mp)
* result is that we return the size of the log as the amount of space left.
*/
STATIC int
-xlog_space_left(xlog_t *log, int cycle, int bytes)
-{
- int free_bytes;
- int tail_bytes;
- int tail_cycle;
-
- tail_bytes = BBTOB(BLOCK_LSN(log->l_tail_lsn));
- tail_cycle = CYCLE_LSN(log->l_tail_lsn);
- if ((tail_cycle == cycle) && (bytes >= tail_bytes)) {
- free_bytes = log->l_logsize - (bytes - tail_bytes);
- } else if ((tail_cycle + 1) < cycle) {
+xlog_space_left(
+ struct log *log,
+ atomic64_t *head)
+{
+ int free_bytes;
+ int tail_bytes;
+ int tail_cycle;
+ int head_cycle;
+ int head_bytes;
+
+ xlog_crack_grant_head(head, &head_cycle, &head_bytes);
+ xlog_crack_atomic_lsn(&log->l_tail_lsn, &tail_cycle, &tail_bytes);
+ tail_bytes = BBTOB(tail_bytes);
+ if (tail_cycle == head_cycle && head_bytes >= tail_bytes)
+ free_bytes = log->l_logsize - (head_bytes - tail_bytes);
+ else if (tail_cycle + 1 < head_cycle)
return 0;
- } else if (tail_cycle < cycle) {
- ASSERT(tail_cycle == (cycle - 1));
- free_bytes = tail_bytes - bytes;
+ else if (tail_cycle < head_cycle) {
+ ASSERT(tail_cycle == (head_cycle - 1));
+ free_bytes = tail_bytes - head_bytes;
} else {
/*
* The reservation head is behind the tail.
@@ -889,12 +856,12 @@ xlog_space_left(xlog_t *log, int cycle, int bytes)
"xlog_space_left: head behind tail\n"
" tail_cycle = %d, tail_bytes = %d\n"
" GH cycle = %d, GH bytes = %d",
- tail_cycle, tail_bytes, cycle, bytes);
+ tail_cycle, tail_bytes, head_cycle, head_bytes);
ASSERT(0);
free_bytes = log->l_logsize;
}
return free_bytes;
-} /* xlog_space_left */
+}
/*
@@ -1047,12 +1014,16 @@ xlog_alloc_log(xfs_mount_t *mp,
log->l_flags |= XLOG_ACTIVE_RECOVERY;
log->l_prev_block = -1;
- log->l_tail_lsn = xlog_assign_lsn(1, 0);
/* log->l_tail_lsn = 0x100000000LL; cycle = 1; current block = 0 */
- log->l_last_sync_lsn = log->l_tail_lsn;
+ xlog_assign_atomic_lsn(&log->l_tail_lsn, 1, 0);
+ xlog_assign_atomic_lsn(&log->l_last_sync_lsn, 1, 0);
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;
+ xlog_assign_grant_head(&log->l_grant_reserve_head, 1, 0);
+ xlog_assign_grant_head(&log->l_grant_write_head, 1, 0);
+ INIT_LIST_HEAD(&log->l_reserveq);
+ INIT_LIST_HEAD(&log->l_writeq);
+ spin_lock_init(&log->l_grant_reserve_lock);
+ spin_lock_init(&log->l_grant_write_lock);
error = EFSCORRUPTED;
if (xfs_sb_version_hassector(&mp->m_sb)) {
@@ -1094,8 +1065,7 @@ xlog_alloc_log(xfs_mount_t *mp,
log->l_xbuf = bp;
spin_lock_init(&log->l_icloglock);
- spin_lock_init(&log->l_grant_lock);
- sv_init(&log->l_flush_wait, 0, "flush_wait");
+ init_waitqueue_head(&log->l_flush_wait);
/* log record size must be multiple of BBSIZE; see xlog_rec_header_t */
ASSERT((XFS_BUF_SIZE(bp) & BBMASK) == 0);
@@ -1151,8 +1121,8 @@ xlog_alloc_log(xfs_mount_t *mp,
ASSERT(XFS_BUF_ISBUSY(iclog->ic_bp));
ASSERT(XFS_BUF_VALUSEMA(iclog->ic_bp) <= 0);
- sv_init(&iclog->ic_force_wait, SV_DEFAULT, "iclog-force");
- sv_init(&iclog->ic_write_wait, SV_DEFAULT, "iclog-write");
+ init_waitqueue_head(&iclog->ic_force_wait);
+ init_waitqueue_head(&iclog->ic_write_wait);
iclogp = &iclog->ic_next;
}
@@ -1167,15 +1137,11 @@ xlog_alloc_log(xfs_mount_t *mp,
out_free_iclog:
for (iclog = log->l_iclog; iclog; iclog = prev_iclog) {
prev_iclog = iclog->ic_next;
- if (iclog->ic_bp) {
- sv_destroy(&iclog->ic_force_wait);
- sv_destroy(&iclog->ic_write_wait);
+ if (iclog->ic_bp)
xfs_buf_free(iclog->ic_bp);
- }
kmem_free(iclog);
}
spinlock_destroy(&log->l_icloglock);
- spinlock_destroy(&log->l_grant_lock);
xfs_buf_free(log->l_xbuf);
out_free_log:
kmem_free(log);
@@ -1223,61 +1189,60 @@ xlog_commit_record(
* water mark. In this manner, we would be creating a low water mark.
*/
STATIC void
-xlog_grant_push_ail(xfs_mount_t *mp,
- int need_bytes)
+xlog_grant_push_ail(
+ struct log *log,
+ int need_bytes)
{
- xlog_t *log = mp->m_log; /* pointer to the log */
- xfs_lsn_t tail_lsn; /* lsn of the log tail */
- xfs_lsn_t threshold_lsn = 0; /* lsn we'd like to be at */
- int free_blocks; /* free blocks left to write to */
- int free_bytes; /* free bytes left to write to */
- int threshold_block; /* block in lsn we'd like to be at */
- int threshold_cycle; /* lsn cycle we'd like to be at */
- int free_threshold;
-
- ASSERT(BTOBB(need_bytes) < log->l_logBBsize);
-
- spin_lock(&log->l_grant_lock);
- free_bytes = xlog_space_left(log,
- log->l_grant_reserve_cycle,
- log->l_grant_reserve_bytes);
- tail_lsn = log->l_tail_lsn;
- free_blocks = BTOBBT(free_bytes);
-
- /*
- * Set the threshold for the minimum number of free blocks in the
- * log to the maximum of what the caller needs, one quarter of the
- * log, and 256 blocks.
- */
- free_threshold = BTOBB(need_bytes);
- free_threshold = MAX(free_threshold, (log->l_logBBsize >> 2));
- free_threshold = MAX(free_threshold, 256);
- if (free_blocks < free_threshold) {
- threshold_block = BLOCK_LSN(tail_lsn) + free_threshold;
- threshold_cycle = CYCLE_LSN(tail_lsn);
+ xfs_lsn_t threshold_lsn = 0;
+ xfs_lsn_t last_sync_lsn;
+ int free_blocks;
+ int free_bytes;
+ int threshold_block;
+ int threshold_cycle;
+ int free_threshold;
+
+ ASSERT(BTOBB(need_bytes) < log->l_logBBsize);
+
+ free_bytes = xlog_space_left(log, &log->l_grant_reserve_head);
+ free_blocks = BTOBBT(free_bytes);
+
+ /*
+ * Set the threshold for the minimum number of free blocks in the
+ * log to the maximum of what the caller needs, one quarter of the
+ * log, and 256 blocks.
+ */
+ free_threshold = BTOBB(need_bytes);
+ free_threshold = MAX(free_threshold, (log->l_logBBsize >> 2));
+ free_threshold = MAX(free_threshold, 256);
+ if (free_blocks >= free_threshold)
+ return;
+
+ xlog_crack_atomic_lsn(&log->l_tail_lsn, &threshold_cycle,
+ &threshold_block);
+ threshold_block += free_threshold;
if (threshold_block >= log->l_logBBsize) {
- threshold_block -= log->l_logBBsize;
- threshold_cycle += 1;
+ threshold_block -= log->l_logBBsize;
+ threshold_cycle += 1;
}
- threshold_lsn = xlog_assign_lsn(threshold_cycle, threshold_block);
+ threshold_lsn = xlog_assign_lsn(threshold_cycle,
+ threshold_block);
+ /*
+ * Don't pass in an lsn greater than the lsn of the last
+ * log record known to be on disk. Use a snapshot of the last sync lsn
+ * so that it doesn't change between the compare and the set.
+ */
+ last_sync_lsn = atomic64_read(&log->l_last_sync_lsn);
+ if (XFS_LSN_CMP(threshold_lsn, last_sync_lsn) > 0)
+ threshold_lsn = last_sync_lsn;
- /* Don't pass in an lsn greater than the lsn of the last
- * log record known to be on disk.
+ /*
+ * Get the transaction layer to kick the dirty buffers out to
+ * disk asynchronously. No point in trying to do this if
+ * the filesystem is shutting down.
*/
- if (XFS_LSN_CMP(threshold_lsn, log->l_last_sync_lsn) > 0)
- threshold_lsn = log->l_last_sync_lsn;
- }
- spin_unlock(&log->l_grant_lock);
-
- /*
- * Get the transaction layer to kick the dirty buffers out to
- * disk asynchronously. No point in trying to do this if
- * the filesystem is shutting down.
- */
- if (threshold_lsn &&
- !XLOG_FORCED_SHUTDOWN(log))
- xfs_trans_ail_push(log->l_ailp, threshold_lsn);
-} /* xlog_grant_push_ail */
+ if (!XLOG_FORCED_SHUTDOWN(log))
+ xfs_trans_ail_push(log->l_ailp, threshold_lsn);
+}
/*
* The bdstrat callback function for log bufs. This gives us a central
@@ -1372,9 +1337,8 @@ xlog_sync(xlog_t *log,
roundoff < BBTOB(1)));
/* move grant heads by roundoff in sync */
- spin_lock(&log->l_grant_lock);
- xlog_grant_add_space(log, roundoff);
- spin_unlock(&log->l_grant_lock);
+ xlog_grant_add_space(log, &log->l_grant_reserve_head, roundoff);
+ xlog_grant_add_space(log, &log->l_grant_write_head, roundoff);
/* put cycle number in every block */
xlog_pack_data(log, iclog, roundoff);
@@ -1489,15 +1453,12 @@ xlog_dealloc_log(xlog_t *log)
iclog = log->l_iclog;
for (i=0; i<log->l_iclog_bufs; i++) {
- sv_destroy(&iclog->ic_force_wait);
- sv_destroy(&iclog->ic_write_wait);
xfs_buf_free(iclog->ic_bp);
next_iclog = iclog->ic_next;
kmem_free(iclog);
iclog = next_iclog;
}
spinlock_destroy(&log->l_icloglock);
- spinlock_destroy(&log->l_grant_lock);
xfs_buf_free(log->l_xbuf);
log->l_mp->m_log = NULL;
@@ -2232,7 +2193,7 @@ xlog_state_do_callback(
lowest_lsn = xlog_get_lowest_lsn(log);
if (lowest_lsn &&
XFS_LSN_CMP(lowest_lsn,
- be64_to_cpu(iclog->ic_header.h_lsn)) < 0) {
+ be64_to_cpu(iclog->ic_header.h_lsn)) < 0) {
iclog = iclog->ic_next;
continue; /* Leave this iclog for
* another thread */
@@ -2240,23 +2201,21 @@ xlog_state_do_callback(
iclog->ic_state = XLOG_STATE_CALLBACK;
- spin_unlock(&log->l_icloglock);
- /* l_last_sync_lsn field protected by
- * l_grant_lock. Don't worry about iclog's lsn.
- * No one else can be here except us.
+ /*
+ * update the last_sync_lsn before we drop the
+ * icloglock to ensure we are the only one that
+ * can update it.
*/
- spin_lock(&log->l_grant_lock);
- ASSERT(XFS_LSN_CMP(log->l_last_sync_lsn,
- be64_to_cpu(iclog->ic_header.h_lsn)) <= 0);
- log->l_last_sync_lsn =
- be64_to_cpu(iclog->ic_header.h_lsn);
- spin_unlock(&log->l_grant_lock);
+ ASSERT(XFS_LSN_CMP(atomic64_read(&log->l_last_sync_lsn),
+ be64_to_cpu(iclog->ic_header.h_lsn)) <= 0);
+ atomic64_set(&log->l_last_sync_lsn,
+ be64_to_cpu(iclog->ic_header.h_lsn));
- } else {
- spin_unlock(&log->l_icloglock);
+ } else
ioerrors++;
- }
+
+ spin_unlock(&log->l_icloglock);
/*
* Keep processing entries in the callback list until
@@ -2297,7 +2256,7 @@ xlog_state_do_callback(
xlog_state_clean_log(log);
/* wake up threads waiting in xfs_log_force() */
- sv_broadcast(&iclog->ic_force_wait);
+ wake_up_all(&iclog->ic_force_wait);
iclog = iclog->ic_next;
} while (first_iclog != iclog);
@@ -2344,7 +2303,7 @@ xlog_state_do_callback(
spin_unlock(&log->l_icloglock);
if (wake)
- sv_broadcast(&log->l_flush_wait);
+ wake_up_all(&log->l_flush_wait);
}
@@ -2395,7 +2354,7 @@ xlog_state_done_syncing(
* iclog buffer, we wake them all, one will get to do the
* I/O, the others get to wait for the result.
*/
- sv_broadcast(&iclog->ic_write_wait);
+ wake_up_all(&iclog->ic_write_wait);
spin_unlock(&log->l_icloglock);
xlog_state_do_callback(log, aborted, iclog); /* also cleans log */
} /* xlog_state_done_syncing */
@@ -2444,7 +2403,7 @@ restart:
XFS_STATS_INC(xs_log_noiclogs);
/* Wait for log writes to have flushed */
- sv_wait(&log->l_flush_wait, 0, &log->l_icloglock, 0);
+ xlog_wait(&log->l_flush_wait, &log->l_icloglock);
goto restart;
}
@@ -2527,6 +2486,18 @@ restart:
*
* 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
+ * path. Hence any lock will be globally hot if we take it unconditionally on
+ * 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.
*/
STATIC int
xlog_grant_log_space(xlog_t *log,
@@ -2534,24 +2505,27 @@ xlog_grant_log_space(xlog_t *log,
{
int free_bytes;
int need_bytes;
-#ifdef DEBUG
- xfs_lsn_t tail_lsn;
-#endif
-
#ifdef DEBUG
if (log->l_flags & XLOG_ACTIVE_RECOVERY)
panic("grant Recovery problem");
#endif
- /* Is there space or do we need to sleep? */
- spin_lock(&log->l_grant_lock);
-
trace_xfs_log_grant_enter(log, tic);
+ 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 (log->l_reserve_headq) {
- xlog_ins_ticketq(&log->l_reserve_headq, tic);
+ 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);
@@ -2563,72 +2537,57 @@ xlog_grant_log_space(xlog_t *log,
goto error_return;
XFS_STATS_INC(xs_sleep_logspace);
- sv_wait(&tic->t_wait, PINOD|PLTWAIT, &log->l_grant_lock, s);
+ 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);
- spin_lock(&log->l_grant_lock);
}
- if (tic->t_flags & XFS_LOG_PERM_RESERV)
- need_bytes = tic->t_unit_res*tic->t_ocnt;
- else
- need_bytes = tic->t_unit_res;
redo:
if (XLOG_FORCED_SHUTDOWN(log))
- goto error_return;
+ goto error_return_unlocked;
- free_bytes = xlog_space_left(log, log->l_grant_reserve_cycle,
- log->l_grant_reserve_bytes);
+ free_bytes = xlog_space_left(log, &log->l_grant_reserve_head);
if (free_bytes < need_bytes) {
- if ((tic->t_flags & XLOG_TIC_IN_Q) == 0)
- xlog_ins_ticketq(&log->l_reserve_headq, tic);
+ 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);
- spin_unlock(&log->l_grant_lock);
- xlog_grant_push_ail(log->l_mp, need_bytes);
- spin_lock(&log->l_grant_lock);
-
- XFS_STATS_INC(xs_sleep_logspace);
- sv_wait(&tic->t_wait, PINOD|PLTWAIT, &log->l_grant_lock, s);
-
- spin_lock(&log->l_grant_lock);
if (XLOG_FORCED_SHUTDOWN(log))
goto error_return;
- trace_xfs_log_grant_wake2(log, tic);
+ 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;
- } else if (tic->t_flags & XLOG_TIC_IN_Q)
- xlog_del_ticketq(&log->l_reserve_headq, tic);
+ }
- /* we've got enough space */
- xlog_grant_add_space(log, need_bytes);
-#ifdef DEBUG
- tail_lsn = log->l_tail_lsn;
- /*
- * Check to make sure the grant write head didn't just over lap the
- * tail. If the cycles are the same, we can't be overlapping.
- * Otherwise, make sure that the cycles differ by exactly one and
- * check the byte count.
- */
- if (CYCLE_LSN(tail_lsn) != log->l_grant_write_cycle) {
- ASSERT(log->l_grant_write_cycle-1 == CYCLE_LSN(tail_lsn));
- ASSERT(log->l_grant_write_bytes <= BBTOB(BLOCK_LSN(tail_lsn)));
+ if (!list_empty(&tic->t_queue)) {
+ spin_lock(&log->l_grant_reserve_lock);
+ list_del_init(&tic->t_queue);
+ spin_unlock(&log->l_grant_reserve_lock);
}
-#endif
+
+ /* 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_head(log, 1);
- spin_unlock(&log->l_grant_lock);
+ xlog_verify_grant_tail(log);
return 0;
- error_return:
- if (tic->t_flags & XLOG_TIC_IN_Q)
- xlog_del_ticketq(&log->l_reserve_headq, tic);
-
+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);
/*
@@ -2638,7 +2597,6 @@ redo:
*/
tic->t_curr_res = 0;
tic->t_cnt = 0; /* ungrant will give back unit_res * t_cnt. */
- spin_unlock(&log->l_grant_lock);
return XFS_ERROR(EIO);
} /* xlog_grant_log_space */
@@ -2646,17 +2604,14 @@ redo:
/*
* Replenish the byte reservation required by moving the grant write head.
*
- *
+ * Similar to xlog_grant_log_space, the function is structured to have a lock
+ * free fast path.
*/
STATIC int
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
tic->t_curr_res = tic->t_unit_res;
xlog_tic_reset_res(tic);
@@ -2669,12 +2624,9 @@ xlog_regrant_write_log_space(xlog_t *log,
panic("regrant Recovery problem");
#endif
- spin_lock(&log->l_grant_lock);
-
trace_xfs_log_regrant_write_enter(log, tic);
-
if (XLOG_FORCED_SHUTDOWN(log))
- goto error_return;
+ 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,
@@ -2683,92 +2635,76 @@ xlog_regrant_write_log_space(xlog_t *log,
* this transaction.
*/
need_bytes = tic->t_unit_res;
- if ((ntic = log->l_write_headq)) {
- free_bytes = xlog_space_left(log, log->l_grant_write_cycle,
- log->l_grant_write_bytes);
- do {
+ 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;
- 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);
+ 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);
- spin_unlock(&log->l_grant_lock);
- xlog_grant_push_ail(log->l_mp, need_bytes);
- spin_lock(&log->l_grant_lock);
+ xlog_grant_push_ail(log, need_bytes);
XFS_STATS_INC(xs_sleep_logspace);
- sv_wait(&tic->t_wait, PINOD|PLTWAIT,
- &log->l_grant_lock, s);
-
- /* If we're shutting down, this tic is already
- * off the queue */
- spin_lock(&log->l_grant_lock);
- if (XLOG_FORCED_SHUTDOWN(log))
- goto error_return;
-
+ 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;
+ goto error_return_unlocked;
- free_bytes = xlog_space_left(log, log->l_grant_write_cycle,
- log->l_grant_write_bytes);
+ free_bytes = xlog_space_left(log, &log->l_grant_write_head);
if (free_bytes < need_bytes) {
- if ((tic->t_flags & XLOG_TIC_IN_Q) == 0)
- xlog_ins_ticketq(&log->l_write_headq, tic);
- spin_unlock(&log->l_grant_lock);
- xlog_grant_push_ail(log->l_mp, need_bytes);
- spin_lock(&log->l_grant_lock);
-
- XFS_STATS_INC(xs_sleep_logspace);
- trace_xfs_log_regrant_write_sleep2(log, tic);
-
- sv_wait(&tic->t_wait, PINOD|PLTWAIT, &log->l_grant_lock, s);
+ spin_lock(&log->l_grant_write_lock);
+ if (list_empty(&tic->t_queue))
+ list_add_tail(&tic->t_queue, &log->l_writeq);
- /* If we're shutting down, this tic is already off the queue */
- spin_lock(&log->l_grant_lock);
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;
- } else if (tic->t_flags & XLOG_TIC_IN_Q)
- xlog_del_ticketq(&log->l_write_headq, tic);
+ }
- /* we've got enough space */
- xlog_grant_add_space_write(log, need_bytes);
-#ifdef DEBUG
- tail_lsn = log->l_tail_lsn;
- if (CYCLE_LSN(tail_lsn) != log->l_grant_write_cycle) {
- ASSERT(log->l_grant_write_cycle-1 == CYCLE_LSN(tail_lsn));
- ASSERT(log->l_grant_write_bytes <= BBTOB(BLOCK_LSN(tail_lsn)));
+ if (!list_empty(&tic->t_queue)) {
+ spin_lock(&log->l_grant_write_lock);
+ list_del_init(&tic->t_queue);
+ spin_unlock(&log->l_grant_write_lock);
}
-#endif
+ /* we've got enough space */
+ xlog_grant_add_space(log, &log->l_grant_write_head, need_bytes);
trace_xfs_log_regrant_write_exit(log, tic);
-
- xlog_verify_grant_head(log, 1);
- spin_unlock(&log->l_grant_lock);
+ xlog_verify_grant_tail(log);
return 0;
+ error_return_unlocked:
+ spin_lock(&log->l_grant_write_lock);
error_return:
- if (tic->t_flags & XLOG_TIC_IN_Q)
- xlog_del_ticketq(&log->l_reserve_headq, tic);
-
+ list_del_init(&tic->t_queue);
+ spin_unlock(&log->l_grant_write_lock);
trace_xfs_log_regrant_write_error(log, tic);
/*
@@ -2778,7 +2714,6 @@ redo:
*/
tic->t_curr_res = 0;
tic->t_cnt = 0; /* ungrant will give back unit_res * t_cnt. */
- spin_unlock(&log->l_grant_lock);
return XFS_ERROR(EIO);
} /* xlog_regrant_write_log_space */
@@ -2799,27 +2734,24 @@ xlog_regrant_reserve_log_space(xlog_t *log,
if (ticket->t_cnt > 0)
ticket->t_cnt--;
- spin_lock(&log->l_grant_lock);
- xlog_grant_sub_space(log, ticket->t_curr_res);
+ xlog_grant_sub_space(log, &log->l_grant_reserve_head,
+ ticket->t_curr_res);
+ xlog_grant_sub_space(log, &log->l_grant_write_head,
+ ticket->t_curr_res);
ticket->t_curr_res = ticket->t_unit_res;
xlog_tic_reset_res(ticket);
trace_xfs_log_regrant_reserve_sub(log, ticket);
- xlog_verify_grant_head(log, 1);
-
/* just return if we still have some of the pre-reserved space */
- if (ticket->t_cnt > 0) {
- spin_unlock(&log->l_grant_lock);
+ if (ticket->t_cnt > 0)
return;
- }
- xlog_grant_add_space_reserve(log, ticket->t_unit_res);
+ xlog_grant_add_space(log, &log->l_grant_reserve_head,
+ ticket->t_unit_res);
trace_xfs_log_regrant_reserve_exit(log, ticket);
- xlog_verify_grant_head(log, 0);
- spin_unlock(&log->l_grant_lock);
ticket->t_curr_res = ticket->t_unit_res;
xlog_tic_reset_res(ticket);
} /* xlog_regrant_reserve_log_space */
@@ -2843,28 +2775,29 @@ STATIC void
xlog_ungrant_log_space(xlog_t *log,
xlog_ticket_t *ticket)
{
+ int bytes;
+
if (ticket->t_cnt > 0)
ticket->t_cnt--;
- spin_lock(&log->l_grant_lock);
trace_xfs_log_ungrant_enter(log, ticket);
-
- xlog_grant_sub_space(log, ticket->t_curr_res);
-
trace_xfs_log_ungrant_sub(log, ticket);
- /* If this is a permanent reservation ticket, we may be able to free
+ /*
+ * If this is a permanent reservation ticket, we may be able to free
* up more space based on the remaining count.
*/
+ bytes = ticket->t_curr_res;
if (ticket->t_cnt > 0) {
ASSERT(ticket->t_flags & XLOG_TIC_PERM_RESERV);
- xlog_grant_sub_space(log, ticket->t_unit_res*ticket->t_cnt);
+ bytes += ticket->t_unit_res*ticket->t_cnt;
}
+ xlog_grant_sub_space(log, &log->l_grant_reserve_head, bytes);
+ xlog_grant_sub_space(log, &log->l_grant_write_head, bytes);
+
trace_xfs_log_ungrant_exit(log, ticket);
- xlog_verify_grant_head(log, 1);
- spin_unlock(&log->l_grant_lock);
xfs_log_move_tail(log->l_mp, 1);
} /* xlog_ungrant_log_space */
@@ -2901,11 +2834,11 @@ xlog_state_release_iclog(
if (iclog->ic_state == XLOG_STATE_WANT_SYNC) {
/* update tail before writing to iclog */
- xlog_assign_tail_lsn(log->l_mp);
+ xfs_lsn_t tail_lsn = xlog_assign_tail_lsn(log->l_mp);
sync++;
iclog->ic_state = XLOG_STATE_SYNCING;
- iclog->ic_header.h_tail_lsn = cpu_to_be64(log->l_tail_lsn);
- xlog_verify_tail_lsn(log, iclog, log->l_tail_lsn);
+ iclog->ic_header.h_tail_lsn = cpu_to_be64(tail_lsn);
+ xlog_verify_tail_lsn(log, iclog, tail_lsn);
/* cycle incremented when incrementing curr_block */
}
spin_unlock(&log->l_icloglock);
@@ -3088,7 +3021,7 @@ maybe_sleep:
return XFS_ERROR(EIO);
}
XFS_STATS_INC(xs_log_force_sleep);
- sv_wait(&iclog->ic_force_wait, PINOD, &log->l_icloglock, s);
+ xlog_wait(&iclog->ic_force_wait, &log->l_icloglock);
/*
* No need to grab the log lock here since we're
* only deciding whether or not to return EIO
@@ -3206,8 +3139,8 @@ try_again:
XFS_STATS_INC(xs_log_force_sleep);
- sv_wait(&iclog->ic_prev->ic_write_wait,
- PSWP, &log->l_icloglock, s);
+ xlog_wait(&iclog->ic_prev->ic_write_wait,
+ &log->l_icloglock);
if (log_flushed)
*log_flushed = 1;
already_slept = 1;
@@ -3235,7 +3168,7 @@ try_again:
return XFS_ERROR(EIO);
}
XFS_STATS_INC(xs_log_force_sleep);
- sv_wait(&iclog->ic_force_wait, PSWP, &log->l_icloglock, s);
+ xlog_wait(&iclog->ic_force_wait, &log->l_icloglock);
/*
* No need to grab the log lock here since we're
* only deciding whether or not to return EIO
@@ -3310,10 +3243,8 @@ 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 *
@@ -3435,6 +3366,7 @@ 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;
@@ -3445,7 +3377,7 @@ 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);
@@ -3484,18 +3416,25 @@ xlog_verify_dest_ptr(
}
STATIC void
-xlog_verify_grant_head(xlog_t *log, int equals)
+xlog_verify_grant_tail(
+ struct log *log)
{
- if (log->l_grant_reserve_cycle == log->l_grant_write_cycle) {
- if (equals)
- ASSERT(log->l_grant_reserve_bytes >= log->l_grant_write_bytes);
- else
- ASSERT(log->l_grant_reserve_bytes > log->l_grant_write_bytes);
- } else {
- ASSERT(log->l_grant_reserve_cycle-1 == log->l_grant_write_cycle);
- ASSERT(log->l_grant_write_bytes >= log->l_grant_reserve_bytes);
- }
-} /* xlog_verify_grant_head */
+ int tail_cycle, tail_blocks;
+ int cycle, space;
+
+ /*
+ * Check to make sure the grant write head didn't just over lap the
+ * tail. If the cycles are the same, we can't be overlapping.
+ * Otherwise, make sure that the cycles differ by exactly one and
+ * check the byte count.
+ */
+ xlog_crack_grant_head(&log->l_grant_write_head, &cycle, &space);
+ xlog_crack_atomic_lsn(&log->l_tail_lsn, &tail_cycle, &tail_blocks);
+ if (tail_cycle != cycle) {
+ ASSERT(cycle - 1 == tail_cycle);
+ ASSERT(space <= BBTOB(tail_blocks));
+ }
+}
/* check if it will fit */
STATIC void
@@ -3716,12 +3655,10 @@ xfs_log_force_umount(
xlog_cil_force(log);
/*
- * We must hold both the GRANT lock and the LOG lock,
- * before we mark the filesystem SHUTDOWN and wake
- * everybody up to tell the bad news.
+ * mark the filesystem and the as in a shutdown state and wake
+ * everybody up to tell them the bad news.
*/
spin_lock(&log->l_icloglock);
- spin_lock(&log->l_grant_lock);
mp->m_flags |= XFS_MOUNT_FS_SHUTDOWN;
if (mp->m_sb_bp)
XFS_BUF_DONE(mp->m_sb_bp);
@@ -3742,27 +3679,21 @@ 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 grant locks.
*/
- if ((tic = log->l_reserve_headq)) {
- do {
- sv_signal(&tic->t_wait);
- tic = tic->t_next;
- } while (tic != log->l_reserve_headq);
- }
-
- if ((tic = log->l_write_headq)) {
- do {
- sv_signal(&tic->t_wait);
- tic = tic->t_next;
- } while (tic != log->l_write_headq);
- }
- spin_unlock(&log->l_grant_lock);
+ spin_lock(&log->l_grant_reserve_lock);
+ list_for_each_entry(tic, &log->l_reserveq, t_queue)
+ wake_up(&tic->t_wait);
+ spin_unlock(&log->l_grant_reserve_lock);
+
+ spin_lock(&log->l_grant_write_lock);
+ list_for_each_entry(tic, &log->l_writeq, t_queue)
+ wake_up(&tic->t_wait);
+ spin_unlock(&log->l_grant_write_lock);
if (!(log->l_iclog->ic_state & XLOG_STATE_IOERROR)) {
ASSERT(!logerror);