Streamline the conditionals so that it is more obvious which specific case
form the top of the function comments is being handled. Use gotos only
for early returns.
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
fs/xfs/xfs_log.c | 144 ++++++++++++++++++++++++-------------------------------
1 file changed, 63 insertions(+), 81 deletions(-)
diff --git a/fs/xfs/xfs_log.c b/fs/xfs/xfs_log.c
index 14ab660a0bae..a37a8defcd39 100644
--- a/fs/xfs/xfs_log.c
+++ b/fs/xfs/xfs_log.c
@@ -3318,99 +3318,81 @@ xfs_log_force(
xlog_cil_force(log);
spin_lock(&log->l_icloglock);
-
iclog = log->l_iclog;
- if (iclog->ic_state & XLOG_STATE_IOERROR) {
- spin_unlock(&log->l_icloglock);
- return -EIO;
- }
+ if (iclog->ic_state & XLOG_STATE_IOERROR)
+ goto out_error;
- /* If the head iclog is not active nor dirty, we just attach
- * ourselves to the head and go to sleep.
- */
- if (iclog->ic_state == XLOG_STATE_ACTIVE ||
- iclog->ic_state == XLOG_STATE_DIRTY) {
+ if (iclog->ic_state == XLOG_STATE_DIRTY ||
+ (iclog->ic_state == XLOG_STATE_ACTIVE &&
+ atomic_read(&iclog->ic_refcnt) == 0 && iclog->ic_offset == 0)) {
/*
- * If the head is dirty or (active and empty), then
- * we need to look at the previous iclog. If the previous
- * iclog is active or dirty we are done. There is nothing
- * to sync out. Otherwise, we attach ourselves to the
+ * If the head is dirty or (active and empty), then we need to
+ * look at the previous iclog.
+ *
+ * If the previous iclog is active or dirty we are done. There
+ * is nothing to sync out. Otherwise, we attach ourselves to the
* previous iclog and go to sleep.
*/
- if (iclog->ic_state == XLOG_STATE_DIRTY ||
- (atomic_read(&iclog->ic_refcnt) == 0
- && iclog->ic_offset == 0)) {
- iclog = iclog->ic_prev;
- if (iclog->ic_state == XLOG_STATE_ACTIVE ||
- iclog->ic_state == XLOG_STATE_DIRTY)
- goto no_sleep;
- else
- goto maybe_sleep;
- } else {
- if (atomic_read(&iclog->ic_refcnt) == 0) {
- /* We are the only one with access to this
- * iclog. Flush it out now. There should
- * be a roundoff of zero to show that someone
- * has already taken care of the roundoff from
- * the previous sync.
- */
- atomic_inc(&iclog->ic_refcnt);
- lsn = be64_to_cpu(iclog->ic_header.h_lsn);
- xlog_state_switch_iclogs(log, iclog, 0);
- spin_unlock(&log->l_icloglock);
-
- if (xlog_state_release_iclog(log, iclog))
- return -EIO;
+ iclog = iclog->ic_prev;
+ if (iclog->ic_state == XLOG_STATE_ACTIVE ||
+ iclog->ic_state == XLOG_STATE_DIRTY)
+ goto out_unlock;
+ } else if (iclog->ic_state == XLOG_STATE_ACTIVE) {
+ if (atomic_read(&iclog->ic_refcnt) == 0) {
+ /*
+ * We are the only one with access to this iclog.
+ *
+ * Flush it out now. There should be a roundoff of zero
+ * to show that someone has already taken care of the
+ * roundoff from the previous sync.
+ */
+ atomic_inc(&iclog->ic_refcnt);
+ lsn = be64_to_cpu(iclog->ic_header.h_lsn);
+ xlog_state_switch_iclogs(log, iclog, 0);
+ spin_unlock(&log->l_icloglock);
- spin_lock(&log->l_icloglock);
- if (be64_to_cpu(iclog->ic_header.h_lsn) == lsn &&
- iclog->ic_state != XLOG_STATE_DIRTY)
- goto maybe_sleep;
- else
- goto no_sleep;
- } else {
- /* Someone else is writing to this iclog.
- * Use its call to flush out the data. However,
- * the other thread may not force out this LR,
- * so we mark it WANT_SYNC.
- */
- xlog_state_switch_iclogs(log, iclog, 0);
- goto maybe_sleep;
- }
- }
- }
+ if (xlog_state_release_iclog(log, iclog))
+ return -EIO;
- /* By the time we come around again, the iclog could've been filled
- * which would give it another lsn. If we have a new lsn, just
- * return because the relevant data has been flushed.
- */
-maybe_sleep:
- if (flags & XFS_LOG_SYNC) {
- /*
- * We must check if we're shutting down here, before
- * we wait, while we're holding the l_icloglock.
- * Then we check again after waking up, in case our
- * sleep was disturbed by a bad news.
- */
- if (iclog->ic_state & XLOG_STATE_IOERROR) {
- spin_unlock(&log->l_icloglock);
- return -EIO;
+ spin_lock(&log->l_icloglock);
+ if (be64_to_cpu(iclog->ic_header.h_lsn) != lsn ||
+ iclog->ic_state == XLOG_STATE_DIRTY)
+ goto out_unlock;
+ } else {
+ /*
+ * Someone else is writing to this iclog.
+ *
+ * Use its call to flush out the data. However, the
+ * other thread may not force out this LR, so we mark
+ * it WANT_SYNC.
+ */
+ xlog_state_switch_iclogs(log, iclog, 0);
}
- XFS_STATS_INC(mp, xs_log_force_sleep);
- xlog_wait(&iclog->ic_force_wait, &log->l_icloglock);
+ } else {
/*
- * No need to grab the log lock here since we're
- * only deciding whether or not to return EIO
- * and the memory read should be atomic.
+ * If the head iclog is not active nor dirty, we just attach
+ * ourselves to the head and go to sleep if necessary.
*/
- if (iclog->ic_state & XLOG_STATE_IOERROR)
- return -EIO;
- } else {
-
-no_sleep:
- spin_unlock(&log->l_icloglock);
+ ;
}
+
+ if (!(flags & XFS_LOG_SYNC))
+ goto out_unlock;
+
+ if (iclog->ic_state & XLOG_STATE_IOERROR)
+ goto out_error;
+ XFS_STATS_INC(mp, xs_log_force_sleep);
+ xlog_wait(&iclog->ic_force_wait, &log->l_icloglock);
+ if (iclog->ic_state & XLOG_STATE_IOERROR)
+ return -EIO;
return 0;
+
+out_unlock:
+ spin_unlock(&log->l_icloglock);
+ return 0;
+out_error:
+ spin_unlock(&log->l_icloglock);
+ return -EIO;
}
/*
--
2.14.2
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