[PATCH v13 00/10] xfs: Delayed Attributes

Allison Henderson
2020-10-23T06:34:45Z

Hi all,

This set is a subset of a larger series for parent pointers. Delayed attributes
allow attribute operations (set and remove) to be logged and committed in the same
way that other delayed operations do. This allows more complex operations (like
parent pointers) to be broken up into multiple smaller transactions. To do
this, the existing attr operations must be modified to operate as either a
delayed operation or a inline operation since older filesystems will not be
able to use the new log entries. This means that they cannot roll, commit, or
finish transactions. Instead, they return -EAGAIN to allow the calling
function to handle the transaction. In this series, we focus on only the clean
up and refactoring needed to accomplish this. We will introduce delayed attrs
and parent pointers in a later set.

At the moment, I would like people to focus their review efforts on just this
"delayed attribute" sub series, as I think that is a more conservative use of peoples
review time. I also think the set is a bit much to manage all at once, and we
need to get the infrastructure ironed out before we focus too much anything
that depends on it. But I do have the extended series for folks that want to
see the bigger picture of where this is going.

To help organize the set, I've arranged the patches to make sort of mini sets.
I thought it would help reviewers break down the reviewing some. For reviewing
purposes, the set could be broken up into 2 phases:

Delay Ready Attributes: (patches 1-4)
These are the remaining patches belonging to the "Delay Ready" series that
we've been working with. In these patches, transaction handling is removed
from the attr routines, and replaced with a state machine that allows a high
level function to roll the transaction and repeatedly recall the attr routines
until they are finished. The behavior of the attr set/remove routines
are now also compatible as a .finish_item callback
xfs: Add helper xfs_attr_node_remove_step
xfs: Add delay ready attr remove routines
xfs: Add delay ready attr set routines
xfs: Rename __xfs_attr_rmtval_remove

Delayed Attributes: (patches 5 - 10)
These patches go on to fully implement delayed attributes. New attr intent and
done items are introduced for use in the existing logging infrastructure. A
feature bit is added to toggle the feature on and off, and an error tag is added
to test the log replay
xfs: Set up infastructure for deferred attribute operations
xfs: Add xfs_attr_set_deferred and xfs_attr_remove_deferred
xfs: Add feature bit XFS_SB_FEAT_INCOMPAT_LOG_DELATTR
xfs: Enable delayed attributes
xfs Remove unused xfs_attr_-_args.patch
xfs: Add delayed attributes error tag

Updates since v12: Mostly integrating review feed back. I've refactored
xfs_attr_node_removename as discussed in the 2nd patch, and consolidated the
xfs_attr_item members into a single args pointer. I've gotten the dfops
mechanics to drive both delayed and non-delayed operations. Lastly the
xfs_attr_*_args functions are removed at the end of the set since the dfops
machinery replaces it. I did explore reorganizing xfs_da_args, though I think
thats big enough to be a separate project and I wanted to get a v13 out before
too much time gets away. Also updated the extended parent pointer series to
keep it functional for now.

xfs: Add helper xfs_attr_node_remove_step
New

xfs: Add delay ready attr remove routines
Fixed typo in commit message
Rebase adjustments
Refactored xfs_attr_node_removename to xfs_attr_node_removename_iter
Added state XFS_DAC_UNINIT to avoid warnings
Found I could remove blk from dac. Removed to simplify

xfs: Add delay ready attr set routines
Rebase adjustments

xfs: Set up infastructure for deferred attribute operations
Collapsed xfs_attr_item members into a single args pointer
Modified xfs_attr_create_intent routines to return null when delayed attrs not enabled
Modified xfs_trans_attr and xfs_attr_finish_item to avoid handling intent and
done items when delayed attrs not enabled Moved xfs_sb_version_hasdelattr stub
from "xfs: Add feature bit XFS_SB_FEAT_INCOMPAT_LOG_DELATTR" patch to this
patch. Used in managing when intents are recorded
Removed initialization logic from args xfs_attr_finish_item (no longer needed)
Simplified xfs_attr_recover to eliminate looping logic

xfs: Add xfs_attr_set_deferred and xfs_attr_remove_deferred
collapsed parameters into a single args pointer

xfs: Add feature bit XFS_SB_FEAT_INCOMPAT_LOG_DELATTR
Rebase adjustments: Fill in xfs_sb_version_hasdelattr stub from earlier patch

xfs: Enable delayed attributes
Removed logic to test for feature bit which is now handled by delayed attr mechanics

xfs: Remove unused xfs_attr_*_args
New

This series can be viewed on github here:
https://github.com/allisonhenderson/xfs_work/tree/delay_ready_attrs_v13

As well as the extended delayed attribute and parent pointer series:
https://github.com/allisonhenderson/xfs_work/tree/delay_ready_attrs_v13_extended

And the test cases:
https://github.com/allisonhenderson/xfs_work/tree/pptr_xfstests

In order to run the test cases, you will need have the corresponding xfsprogs
changes as well. Which can be found here:
https://github.com/allisonhenderson/xfs_work/tree/delay_ready_attrs_xfsprogs_v13
https://github.com/allisonhenderson/xfs_work/tree/delay_ready_attrs_xfsprogs_v13_extended

To run the xfs attributes tests run:
check -g attr

To run as delayed attributes run:
export MKFS_OPTIONS="-n delattr"
check -g attr

To run parent pointer tests:
check -g parent

I've also made the corresponding updates to the user space side as well, and ported anything
they need to seat correctly.

Questions, comment and feedback appreciated!

Thanks all!
Allison

Allison Collins (5):
xfs: Add helper xfs_attr_node_remove_step
xfs: Rename __xfs_attr_rmtval_remove
xfs: Add xfs_attr_set_deferred and xfs_attr_remove_deferred
xfs: Enable delayed attributes
xfs: Add delayed attributes error tag

Allison Henderson (5):
xfs: Add delay ready attr remove routines
xfs: Add delay ready attr set routines
xfs: Set up infastructure for deferred attribute operations
xfs: Add feature bit XFS_SB_FEAT_INCOMPAT_LOG_DELATTR
xfs: Remove unused xfs_attr_*_args

fs/xfs/Makefile | 1 +
fs/xfs/libxfs/xfs_attr.c | 550 +++++++++++++++++++----------
fs/xfs/libxfs/xfs_attr.h | 218 +++++++++++-
fs/xfs/libxfs/xfs_attr_leaf.c | 2 +-
fs/xfs/libxfs/xfs_attr_remote.c | 110 +++---
fs/xfs/libxfs/xfs_attr_remote.h | 7 +-
fs/xfs/libxfs/xfs_defer.c | 1 +
fs/xfs/libxfs/xfs_defer.h | 3 +
fs/xfs/libxfs/xfs_errortag.h | 4 +-
fs/xfs/libxfs/xfs_format.h | 11 +-
fs/xfs/libxfs/xfs_fs.h | 1 +
fs/xfs/libxfs/xfs_log_format.h | 44 ++-
fs/xfs/libxfs/xfs_log_recover.h | 2 +
fs/xfs/libxfs/xfs_sb.c | 2 +
fs/xfs/libxfs/xfs_types.h | 1 +
fs/xfs/scrub/common.c | 2 +
fs/xfs/xfs_acl.c | 2 +
fs/xfs/xfs_attr_inactive.c | 2 +-
fs/xfs/xfs_attr_item.c | 758 ++++++++++++++++++++++++++++++++++++++++
fs/xfs/xfs_attr_item.h | 76 ++++
fs/xfs/xfs_attr_list.c | 1 +
fs/xfs/xfs_error.c | 3 +
fs/xfs/xfs_ioctl.c | 2 +
fs/xfs/xfs_ioctl32.c | 2 +
fs/xfs/xfs_iops.c | 2 +
fs/xfs/xfs_log.c | 4 +
fs/xfs/xfs_log_recover.c | 2 +
fs/xfs/xfs_ondisk.h | 2 +
fs/xfs/xfs_super.c | 3 +
fs/xfs/xfs_trace.h | 1 -
fs/xfs/xfs_xattr.c | 1 +
31 files changed, 1591 insertions(+), 229 deletions(-)
create mode 100644 fs/xfs/xfs_attr_item.c
create mode 100644 fs/xfs/xfs_attr_item.h

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2.7.4