From: Zhang Yi <yi.zhang@huawei.com>
Changes since v2:
- Rebase the codes on ext4.git dev-91ef18b567da.
- Move the first cleanup patch in v2 to patch 08 to facilitate easier
backporting.
- In patch 01, correct the mismatch comments for
EXT4_EXT_DATA_ENTIRE_VALID1 and EXT4_EXT_DATA_PARTIAL_VALID1.
- Modify patch 06 and add 07, cleanup the commit message to avoid
confusion, and don't always drop extent cache before splitting
extent, instead, do this only after PARTIAL_VALID1 zeroed out or
split extent fails.
- In patch 08, mark zero_ex to initialized.
- In patch 09, correct the word 'tag' to 'lable' in the commit message.
- In patch 11, add return value check of __es_remove_extent() in
ext4_es_cache_extent().
- Collecting RVB tags.
Thanks for the comments and suggestions from Jan, Ojaswin and Baokun!
Next, it is necessary to focus on refactoring and cleaning up the
code related to ext4_split_extent(). Ojaswin is going to take on this
work since he has already been exploring it on his local branch.
Changes since v1:
- Rebase the codes based on the latest linux-next 20251120.
- Add patches 01-05, fix two stale data problems caused by
EXT4_EXT_MAY_ZEROOUT when splitting extent.
- Add patches 06-07, fix two stale extent status entries problems also
caused by splitting extent.
- Modify patches 08-10, extend __es_remove_extent() and
ext4_es_cache_extent() to allow them to overwrite existing extents of
the same status when caching on-disk extents, while also checking
extents of different stauts and raising alarms to prevent misuse.
- Add patch 13 to clear the usage of ext4_es_insert_extent(), and
remove the TODO comment in it.
v2: https://lore.kernel.org/linux-ext4/20251121060811.1685783-1-yi.zhang@huaweicloud.com/
v1: https://lore.kernel.org/linux-ext4/20251031062905.4135909-1-yi.zhang@huaweicloud.com/
Original Description
This series addresses the optimization that Jan pointed out [1]
regarding the introduction of a sequence number to
ext4_es_insert_extent(). The proposal is to replace all instances where
the cache of on-disk extents is updated by using ext4_es_cache_extent()
instead of ext4_es_insert_extent(). This change can prevent excessive
cache invalidations caused by unnecessarily increasing the extent
sequence number when reading from the on-disk extent tree.
[1] https://lore.kernel.org/linux-ext4/ympvfypw3222g2k4xzd5pba4zhkz5jihw4td67iixvrqhuu43y@wse63ntv4s6u/
Cheers,
Yi.
Zhang Yi (14):
ext4: subdivide EXT4_EXT_DATA_VALID1
ext4: don't zero the entire extent if EXT4_EXT_DATA_PARTIAL_VALID1
ext4: don't set EXT4_GET_BLOCKS_CONVERT when splitting before
submitting I/O
ext4: correct the mapping status if the extent has been zeroed
ext4: don't cache extent during splitting extent
ext4: drop extent cache after doing PARTIAL_VALID1 zeroout
ext4: drop extent cache when splitting extent fails
ext4: cleanup zeroout in ext4_split_extent_at()
ext4: cleanup useless out label in __es_remove_extent()
ext4: make __es_remove_extent() check extent status
ext4: make ext4_es_cache_extent() support overwrite existing extents
ext4: adjust the debug info in ext4_es_cache_extent()
ext4: replace ext4_es_insert_extent() when caching on-disk extents
ext4: drop the TODO comment in ext4_es_insert_extent()
fs/ext4/extents.c | 135 ++++++++++++++++++++++++---------------
fs/ext4/extents_status.c | 124 ++++++++++++++++++++++++++---------
fs/ext4/inode.c | 18 +++---
3 files changed, 187 insertions(+), 90 deletions(-)
--
2.46.1