Re: [f2fs-dev] [PATCH v3] f2fs: rename checkpoint=merge mount option to checkpoint_merge
From: Chao Yu
Date: Tue Feb 02 2021 - 04:56:42 EST
On 2021/2/2 17:44, Daeho Jeong wrote:
When we remount it without the "checkpoint_merge" option, shouldn't we
need to clear "MERGE_CHECKPOINT" again?
This is actually what I intended, but I was wrong. Actually, I found this.
When we remount the filesystem, the previous mount option is passed
through the "data" argument in the below.
f2fs_remount(struct super_block *sb, int *flags, char *data)
If we don't provide the "nocheckpoint_merge" option, how can we turn
off the "checkpoint_merge" option which is turned on in the previous
mount?
We can use "mount -o remount /dev/xxx /mnt" to disable checkpoint_merge,
since that command won't pass old mount options to remount?
Quoted from man mount:
mount -o remount,rw /dev/foo /dir
After this call all old mount options are replaced and arbitrary stuff from fstab (or mtab) is ignored, except the loop= option which is internally generated and maintained by the
mount command.
mount -o remount,rw /dir
After this call mount reads fstab and merges these options with the options from the command line (-o). If no mountpoint found in fstab than remount with unspecified source is allowed.
Thanks,
2021년 2월 2일 (화) 오후 6:28, Chao Yu <yuchao0@xxxxxxxxxx>님이 작성:
On 2021/2/2 17:23, Daeho Jeong wrote:
From: Daeho Jeong <daehojeong@xxxxxxxxxx>
As checkpoint=merge comes in, mount option setting related to checkpoint
had been mixed up and it became hard to understand. So, I separated
this option from "checkpoint=" and made another mount option
"checkpoint_merge" for this.
Signed-off-by: Daeho Jeong <daehojeong@xxxxxxxxxx>
---
v2: renamed "checkpoint=merge" to "checkpoint_merge"
v3: removed "nocheckpoint_merge" option
---
Documentation/filesystems/f2fs.rst | 6 +++---
fs/f2fs/super.c | 21 +++++++++------------
2 files changed, 12 insertions(+), 15 deletions(-)
diff --git a/Documentation/filesystems/f2fs.rst b/Documentation/filesystems/f2fs.rst
index d0ead45dc706..475994ed8b15 100644
--- a/Documentation/filesystems/f2fs.rst
+++ b/Documentation/filesystems/f2fs.rst
@@ -247,9 +247,9 @@ checkpoint=%s[:%u[%]] Set to "disable" to turn off checkpointing. Set to "enabl
hide up to all remaining free space. The actual space that
would be unusable can be viewed at /sys/fs/f2fs/<disk>/unusable
This space is reclaimed once checkpoint=enable.
- Here is another option "merge", which creates a kernel daemon
- and makes it to merge concurrent checkpoint requests as much
- as possible to eliminate redundant checkpoint issues. Plus,
+checkpoint_merge When checkpoint is enabled, this can be used to create a kernel
+ daemon and make it to merge concurrent checkpoint requests as
+ much as possible to eliminate redundant checkpoint issues. Plus,
we can eliminate the sluggish issue caused by slow checkpoint
operation when the checkpoint is done in a process context in
a cgroup having low i/o budget and cpu shares. To make this
diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
index 56696f6cfa86..b60dcef7f9d0 100644
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -215,7 +215,7 @@ static match_table_t f2fs_tokens = {
{Opt_checkpoint_disable_cap, "checkpoint=disable:%u"},
{Opt_checkpoint_disable_cap_perc, "checkpoint=disable:%u%%"},
{Opt_checkpoint_enable, "checkpoint=enable"},
- {Opt_checkpoint_merge, "checkpoint=merge"},
+ {Opt_checkpoint_merge, "checkpoint_merge"},
{Opt_compress_algorithm, "compress_algorithm=%s"},
{Opt_compress_log_size, "compress_log_size=%u"},
{Opt_compress_extension, "compress_extension=%s"},
@@ -1142,12 +1142,6 @@ static int parse_options(struct super_block *sb, char *options, bool is_remount)
return -EINVAL;
}
- if (test_opt(sbi, DISABLE_CHECKPOINT) &&
- test_opt(sbi, MERGE_CHECKPOINT)) {
- f2fs_err(sbi, "checkpoint=merge cannot be used with checkpoint=disable\n");
- return -EINVAL;
- }
-
/* Not pass down write hints if the number of active logs is lesser
* than NR_CURSEG_PERSIST_TYPE.
*/
@@ -1782,7 +1776,7 @@ static int f2fs_show_options(struct seq_file *seq, struct dentry *root)
seq_printf(seq, ",checkpoint=disable:%u",
F2FS_OPTION(sbi).unusable_cap);
if (test_opt(sbi, MERGE_CHECKPOINT))
- seq_puts(seq, ",checkpoint=merge");
+ seq_puts(seq, ",checkpoint_merge");
if (F2FS_OPTION(sbi).fsync_mode == FSYNC_MODE_POSIX)
seq_printf(seq, ",fsync_mode=%s", "posix");
else if (F2FS_OPTION(sbi).fsync_mode == FSYNC_MODE_STRICT)
@@ -1827,6 +1821,7 @@ static void default_options(struct f2fs_sb_info *sbi)
sbi->sb->s_flags |= SB_LAZYTIME;
set_opt(sbi, FLUSH_MERGE);
set_opt(sbi, DISCARD);
+ clear_opt(sbi, MERGE_CHECKPOINT);
It's not needed here?
Thanks,
if (f2fs_sb_has_blkzoned(sbi))
F2FS_OPTION(sbi).fs_mode = FS_MODE_LFS;
else
@@ -2066,9 +2061,8 @@ static int f2fs_remount(struct super_block *sb, int *flags, char *data)
}
}
- if (!test_opt(sbi, MERGE_CHECKPOINT)) {
- f2fs_stop_ckpt_thread(sbi);
- } else {
+ if (!test_opt(sbi, DISABLE_CHECKPOINT) &&
+ test_opt(sbi, MERGE_CHECKPOINT)) {
err = f2fs_start_ckpt_thread(sbi);
if (err) {
f2fs_err(sbi,
@@ -2076,6 +2070,8 @@ static int f2fs_remount(struct super_block *sb, int *flags, char *data)
err);
goto restore_gc;
}
+ } else {
+ f2fs_stop_ckpt_thread(sbi);
}
/*
@@ -3831,7 +3827,8 @@ static int f2fs_fill_super(struct super_block *sb, void *data, int silent)
/* setup checkpoint request control and start checkpoint issue thread */
f2fs_init_ckpt_req_control(sbi);
- if (test_opt(sbi, MERGE_CHECKPOINT)) {
+ if (!test_opt(sbi, DISABLE_CHECKPOINT) &&
+ test_opt(sbi, MERGE_CHECKPOINT)) {
err = f2fs_start_ckpt_thread(sbi);
if (err) {
f2fs_err(sbi,
.