[PATCH v2] f2fs: allow writeback on error status filesystem

From: Chao Yu
Date: Mon Jun 08 2020 - 08:01:19 EST


71.07% 0.01% kworker/u256:1+ [kernel.kallsyms] [k] wb_writeback
|
--71.06%--wb_writeback
|
|--68.96%--__writeback_inodes_wb
| |
| --68.95%--writeback_sb_inodes
| |
| |--65.08%--__writeback_single_inode
| | |
| | --64.35%--do_writepages
| | |
| | |--59.83%--f2fs_write_node_pages
| | | |
| | | --59.74%--f2fs_sync_node_pages
| | | |
| | | |--27.91%--pagevec_lookup_range_tag
| | | | |
| | | | --27.90%--find_get_pages_range_tag

If filesystem was injected checkpoint errror, before umount, kworker will
always hold one core in order to writeback a large number of node pages,
that looks not reasonable, to avoid that, we can allow data/node write in
such case, since we can force all data/node writes with OPU mode, and
clear recovery flag on node, and checkpoint is not allowed as well, so we
don't need to worry about writeback's effect on data/node in previous
checkpoint, then with this way, it can decrease memory footprint cost by
node/data pages and avoid looping into data/node writeback process.

Signed-off-by: Chao Yu <yuchao0@xxxxxxxxxx>
---
fs/f2fs/checkpoint.c | 7 +++++++
fs/f2fs/data.c | 22 +++++++++++++++-------
fs/f2fs/node.c | 7 +++++--
3 files changed, 27 insertions(+), 9 deletions(-)

diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c
index 236064930251..1bb8278a1c4a 100644
--- a/fs/f2fs/checkpoint.c
+++ b/fs/f2fs/checkpoint.c
@@ -1238,6 +1238,13 @@ static int block_operations(struct f2fs_sb_info *sbi)
goto retry_flush_nodes;
}

+ if (unlikely(f2fs_cp_error(sbi))) {
+ up_write(&sbi->node_write);
+ up_write(&sbi->node_change);
+ f2fs_unlock_all(sbi);
+ return -EIO;
+ }
+
/*
* sbi->node_change is used only for AIO write_begin path which produces
* dirty node blocks and some checkpoint values by block allocation.
diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index 267b5e76a02b..808e7734db19 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -2508,6 +2508,8 @@ bool f2fs_should_update_outplace(struct inode *inode, struct f2fs_io_info *fio)
{
struct f2fs_sb_info *sbi = F2FS_I_SB(inode);

+ if (unlikely(f2fs_cp_error(sbi)))
+ return true;
if (f2fs_lfs_mode(sbi))
return true;
if (S_ISDIR(inode->i_mode))
@@ -2691,13 +2693,19 @@ int f2fs_write_single_data_page(struct page *page, int *submitted,
/* we should bypass data pages to proceed the kworkder jobs */
if (unlikely(f2fs_cp_error(sbi))) {
mapping_set_error(page->mapping, -EIO);
- /*
- * don't drop any dirty dentry pages for keeping lastest
- * directory structure.
- */
- if (S_ISDIR(inode->i_mode))
- goto redirty_out;
- goto out;
+
+ if (is_sbi_flag_set(sbi, SBI_IS_CLOSE))
+ goto out;
+
+ if (has_not_enough_free_secs(sbi, 0, 0)) {
+ /*
+ * don't drop any dirty dentry pages for keeping lastest
+ * directory structure.
+ */
+ if (S_ISDIR(inode->i_mode))
+ goto redirty_out;
+ goto out;
+ }
}

if (unlikely(is_sbi_flag_set(sbi, SBI_POR_DOING)))
diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
index 03e24df1c84f..372c04efad38 100644
--- a/fs/f2fs/node.c
+++ b/fs/f2fs/node.c
@@ -1527,7 +1527,10 @@ static int __write_node_page(struct page *page, bool atomic, bool *submitted,
unlock_page(page);
return 0;
}
- goto redirty_out;
+ if (has_not_enough_free_secs(sbi, 0, 0))
+ goto redirty_out;
+ set_fsync_mark(page, 0);
+ set_dentry_mark(page, 0);
}

if (unlikely(is_sbi_flag_set(sbi, SBI_POR_DOING)))
@@ -1568,7 +1571,7 @@ static int __write_node_page(struct page *page, bool atomic, bool *submitted,
goto redirty_out;
}

- if (atomic && !test_opt(sbi, NOBARRIER))
+ if (atomic && !test_opt(sbi, NOBARRIER) && !f2fs_cp_error(sbi))
fio.op_flags |= REQ_PREFLUSH | REQ_FUA;

/* should add to global list before clearing PAGECACHE status */
--
2.18.0.rc1