Merge remote-tracking branch 'tip/sched/arm64' into for-next/core

[linux-2.6-microblaze.git] / fs / xfs / xfs_log_cil.c

diff --git a/fs/xfs/xfs_log_cil.c b/fs/xfs/xfs_log_cil.c
index b128aaa..4c44bc3 100644 (file)
--- a/fs/xfs/xfs_log_cil.c
+++ b/fs/xfs/xfs_log_cil.c
@@ -654,8 +654,9 @@ xlog_cil_push_work(
        struct xfs_trans_header thdr;
        struct xfs_log_iovec    lhdr;
        struct xfs_log_vec      lvhdr = { NULL };
+       xfs_lsn_t               preflush_tail_lsn;
        xfs_lsn_t               commit_lsn;
-       xfs_lsn_t               push_seq;
+       xfs_csn_t               push_seq;
        struct bio              bio;
        DECLARE_COMPLETION_ONSTACK(bdev_flush);
 
@@ -730,7 +731,15 @@ xlog_cil_push_work(
         * because we hold the flush lock exclusively. Hence we can now issue
         * a cache flush to ensure all the completed metadata in the journal we
         * are about to overwrite is on stable storage.
+        *
+        * Because we are issuing this cache flush before we've written the
+        * tail lsn to the iclog, we can have metadata IO completions move the
+        * tail forwards between the completion of this flush and the iclog
+        * being written. In this case, we need to re-issue the cache flush
+        * before the iclog write. To detect whether the log tail moves, sample
+        * the tail LSN *before* we issue the flush.
         */
+       preflush_tail_lsn = atomic64_read(&log->l_tail_lsn);
        xfs_flush_bdev_async(&bio, log->l_mp->m_ddev_targp->bt_bdev,
                                &bdev_flush);
 
@@ -941,7 +950,7 @@ restart:
         * storage.
         */
        commit_iclog->ic_flags |= XLOG_ICL_NEED_FUA;
-       xlog_state_release_iclog(log, commit_iclog);
+       xlog_state_release_iclog(log, commit_iclog, preflush_tail_lsn);
        spin_unlock(&log->l_icloglock);
        return;