Skip to content

K
Kernel

openeuler / Kernel
1 年多 前同步成功

通知 8
Star 0
Fork 0
K
Kernel
切换分支/标签
  1. 29 6月, 2019 1 次提交
  3. 13 6月, 2019 1 次提交
  5. 12 6月, 2019 8 次提交
  7. 10 6月, 2019 1 次提交
  9. 04 6月, 2019 1 次提交
  11. 24 5月, 2019 1 次提交
    • D
      xfs: fix broken log reservation debugging · d31d7185
      由 Darrick J. Wong 提交于 
      xlog_print_tic_res() is supposed to print a human readable string for
each element of the log ticket reservation array.  Unfortunately, I
forgot to update the string array when we added rmap & reflink support,
so the debug message prints "region[3]: (null) - 352 bytes" which isn't
useful at all.  Add the missing elements and add a build check so that
we don't forget again to add a string when adding a new XLOG_REG_TYPE.
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
      d31d7185
  13. 21 5月, 2019 2 次提交
  15. 18 5月, 2019 1 次提交
  17. 02 5月, 2019 1 次提交
  19. 30 4月, 2019 4 次提交
  21. 27 4月, 2019 6 次提交
  23. 23 4月, 2019 7 次提交
  25. 17 4月, 2019 6 次提交
    • D
      xfs: merge adjacent io completions of the same type · 3994fc48
      由 Darrick J. Wong 提交于 
      It's possible for pagecache writeback to split up a large amount of work
into smaller pieces for throttling purposes or to reduce the amount of
time a writeback operation is pending.  Whatever the reason, XFS can end
up with a bunch of IO completions that call for the same operation to be
performed on a contiguous extent mapping.  Since mappings are extent
based in XFS, we'd prefer to run fewer transactions when we can.

When we're processing an ioend on the list of io completions, check to
see if the next items on the list are both adjacent and of the same
type.  If so, we can merge the completions to reduce transaction
overhead.

On fast storage this doesn't seem to make much of a difference in
performance, though the number of transactions for an overnight xfstests
run seems to drop by ~5%.
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
      3994fc48
    • D
      xfs: remove unused m_data_workqueue · 28408243
      由 Darrick J. Wong 提交于 
      Now that we're no longer using m_data_workqueue, remove it.
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
      28408243
    • D
      xfs: implement per-inode writeback completion queues · cb357bf3
      由 Darrick J. Wong 提交于 
      When scheduling writeback of dirty file data in the page cache, XFS uses
IO completion workqueue items to ensure that filesystem metadata only
updates after the write completes successfully.  This is essential for
converting unwritten extents to real extents at the right time and
performing COW remappings.

Unfortunately, XFS queues each IO completion work item to an unbounded
workqueue, which means that the kernel can spawn dozens of threads to
try to handle the items quickly.  These threads need to take the ILOCK
to update file metadata, which results in heavy ILOCK contention if a
large number of the work items target a single file, which is
inefficient.

Worse yet, the writeback completion threads get stuck waiting for the
ILOCK while holding transaction reservations, which can use up all
available log reservation space.  When that happens, metadata updates to
other parts of the filesystem grind to a halt, even if the filesystem
could otherwise have handled it.

Even worse, if one of the things grinding to a halt happens to be a
thread in the middle of a defer-ops finish holding the same ILOCK and
trying to obtain more log reservation having exhausted the permanent
reservation, we now have an ABBA deadlock - writeback completion has a
transaction reserved and wants the ILOCK, and someone else has the ILOCK
and wants a transaction reservation.

Therefore, we create a per-inode writeback io completion queue + work
item.  When writeback finishes, it can add the ioend to the per-inode
queue and let the single worker item process that queue.  This
dramatically cuts down on the number of kworkers and ILOCK contention in
the system, and seems to have eliminated an occasional deadlock I was
seeing while running generic/476.

Testing with a program that simulates a heavy random-write workload to a
single file demonstrates that the number of kworkers drops from
approximately 120 threads per file to 1, without dramatically changing
write bandwidth or pagecache access latency.

Note that we leave the xfs-conv workqueue's max_active alone because we
still want to be able to run ioend processing for as many inodes as the
system can handle.
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
      cb357bf3
    • D
      xfs: scrub should only cross-reference with healthy btrees · 4fb7951f
      由 Darrick J. Wong 提交于 
      Skip cross-referencing with a btree if the health report tells us that
it's known to be bad.  This should reduce the dmesg spew considerably.
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: NDave Chinner <dchinner@redhat.com>
      4fb7951f
    • D
      xfs: scrub/repair should update filesystem metadata health · 4860a05d
      由 Darrick J. Wong 提交于 
      Now that we have the ability to track sick metadata in-core, make scrub
and repair update those health assessments after doing work.
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: NDave Chinner <dchinner@redhat.com>
      4860a05d
    • D
      xfs: hoist the already_fixed variable to the scrub context · 160b5a78
      由 Darrick J. Wong 提交于 
      Now that we no longer memset the scrub context, we can move the
already_fixed variable into the scrub context's state flags instead of
passing around pointers to separate stack variables.
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: NDave Chinner <dchinner@redhat.com>
      160b5a78