Re: [PATCH 4/4] f2fs: clean up bggc mount option

From: Jaegeuk Kim
Date: Fri Feb 14 2020 - 13:42:29 EST

On 02/14, Chao Yu wrote:
> There are three status for background gc: on, off and sync, it's
> a little bit confused to use test_opt(BG_GC) and test_opt(FORCE_FG_GC)
> combinations to indicate status of background gc.
>
> So let's remove F2FS_MOUNT_BG_GC and F2FS_MOUNT_FORCE_FG_GC mount

I don't think we can do as well.

> options, and add F2FS_OPTION().bggc_mode with below three status
> to clean up codes and enhance bggc mode's scalability.
>
> enum {
> BGGC_MODE_ON, /* background gc is on */
> BGGC_MODE_OFF, /* background gc is off */
> BGGC_MODE_SYNC, /*
> * background gc is on, migrating blocks
> * like foreground gc
> */
> };
>
> Signed-off-by: Chao Yu <yuchao0@xxxxxxxxxx>
> ---
> fs/f2fs/f2fs.h | 12 ++++++++++--
> fs/f2fs/gc.c | 6 +++++-
> fs/f2fs/super.c | 29 +++++++++++++----------------
> 3 files changed, 28 insertions(+), 19 deletions(-)
>
> diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
> index d2d50827772c..9f65ba8057ad 100644
> --- a/fs/f2fs/f2fs.h
> +++ b/fs/f2fs/f2fs.h
> @@ -74,7 +74,6 @@ extern const char *f2fs_fault_name[FAULT_MAX];
> /*
> * For mount options
> */
> -#define F2FS_MOUNT_BG_GC 0x00000001
> #define F2FS_MOUNT_DISABLE_ROLL_FORWARD 0x00000002
> #define F2FS_MOUNT_DISCARD 0x00000004
> #define F2FS_MOUNT_NOHEAP 0x00000008
> @@ -88,7 +87,6 @@ extern const char *f2fs_fault_name[FAULT_MAX];
> #define F2FS_MOUNT_NOBARRIER 0x00000800
> #define F2FS_MOUNT_FASTBOOT 0x00001000
> #define F2FS_MOUNT_EXTENT_CACHE 0x00002000
> -#define F2FS_MOUNT_FORCE_FG_GC 0x00004000
> #define F2FS_MOUNT_DATA_FLUSH 0x00008000
> #define F2FS_MOUNT_FAULT_INJECTION 0x00010000
> #define F2FS_MOUNT_USRQUOTA 0x00080000
> @@ -137,6 +135,7 @@ struct f2fs_mount_info {
> int alloc_mode; /* segment allocation policy */
> int fsync_mode; /* fsync policy */
> int fs_mode; /* fs mode: LFS or ADAPTIVE */
> + int bggc_mode; /* bggc mode: off, on or sync */
> bool test_dummy_encryption; /* test dummy encryption */
> block_t unusable_cap; /* Amount of space allowed to be
> * unusable when disabling checkpoint
> @@ -1170,6 +1169,15 @@ enum {
> GC_URGENT,
> };
>
> +enum {
> + BGGC_MODE_ON, /* background gc is on */
> + BGGC_MODE_OFF, /* background gc is off */
> + BGGC_MODE_SYNC, /*
> + * background gc is on, migrating blocks
> + * like foreground gc
> + */
> +};
> +
> enum {
> FS_MODE_ADAPTIVE, /* use both lfs/ssr allocation */
> FS_MODE_LFS, /* use lfs allocation only */
> diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c
> index 8aebe2b9c655..897de003e423 100644
> --- a/fs/f2fs/gc.c
> +++ b/fs/f2fs/gc.c
> @@ -31,6 +31,8 @@ static int gc_thread_func(void *data)
>
> set_freezable();
> do {
> + bool sync_mode;
> +
> wait_event_interruptible_timeout(*wq,
> kthread_should_stop() || freezing(current) ||
> gc_th->gc_wake,
> @@ -101,8 +103,10 @@ static int gc_thread_func(void *data)
> do_gc:
> stat_inc_bggc_count(sbi->stat_info);
>
> + sync_mode = F2FS_OPTION(sbi).bggc_mode == BGGC_MODE_SYNC;
> +
> /* if return value is not zero, no victim was selected */
> - if (f2fs_gc(sbi, test_opt(sbi, FORCE_FG_GC), true, NULL_SEGNO))
> + if (f2fs_gc(sbi, sync_mode, true, NULL_SEGNO))
> wait_ms = gc_th->no_gc_sleep_time;
>
> trace_f2fs_background_gc(sbi->sb, wait_ms,
> diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
> index 427409eff354..4ef7e6eb37da 100644
> --- a/fs/f2fs/super.c
> +++ b/fs/f2fs/super.c
> @@ -427,14 +427,11 @@ static int parse_options(struct super_block *sb, char *options)
> if (!name)
> return -ENOMEM;
> if (strlen(name) == 2 && !strncmp(name, "on", 2)) {
> - set_opt(sbi, BG_GC);
> - clear_opt(sbi, FORCE_FG_GC);
> + F2FS_OPTION(sbi).bggc_mode = BGGC_MODE_ON;
> } else if (strlen(name) == 3 && !strncmp(name, "off", 3)) {
> - clear_opt(sbi, BG_GC);
> - clear_opt(sbi, FORCE_FG_GC);
> + F2FS_OPTION(sbi).bggc_mode = BGGC_MODE_OFF;
> } else if (strlen(name) == 4 && !strncmp(name, "sync", 4)) {
> - set_opt(sbi, BG_GC);
> - set_opt(sbi, FORCE_FG_GC);
> + F2FS_OPTION(sbi).bggc_mode = BGGC_MODE_SYNC;
> } else {
> kvfree(name);
> return -EINVAL;
> @@ -1436,14 +1433,13 @@ static int f2fs_show_options(struct seq_file *seq, struct dentry *root)
> {
> struct f2fs_sb_info *sbi = F2FS_SB(root->d_sb);
>
> - if (!f2fs_readonly(sbi->sb) && test_opt(sbi, BG_GC)) {
> - if (test_opt(sbi, FORCE_FG_GC))
> - seq_printf(seq, ",background_gc=%s", "sync");
> - else
> - seq_printf(seq, ",background_gc=%s", "on");
> - } else {
> + if (F2FS_OPTION(sbi).bggc_mode == BGGC_MODE_SYNC)
> + seq_printf(seq, ",background_gc=%s", "sync");
> + else if (F2FS_OPTION(sbi).bggc_mode == BGGC_MODE_ON)
> + seq_printf(seq, ",background_gc=%s", "on");
> + else if (F2FS_OPTION(sbi).bggc_mode == BGGC_MODE_OFF)
> seq_printf(seq, ",background_gc=%s", "off");
> - }
> +
> if (test_opt(sbi, DISABLE_ROLL_FORWARD))
> seq_puts(seq, ",disable_roll_forward");
> if (test_opt(sbi, DISCARD))
> @@ -1573,8 +1569,8 @@ static void default_options(struct f2fs_sb_info *sbi)
> F2FS_OPTION(sbi).compress_algorithm = COMPRESS_LZO;
> F2FS_OPTION(sbi).compress_log_size = MIN_COMPRESS_LOG_SIZE;
> F2FS_OPTION(sbi).compress_ext_cnt = 0;
> + F2FS_OPTION(sbi).bggc_mode = BGGC_MODE_ON;
>
> - set_opt(sbi, BG_GC);
> set_opt(sbi, INLINE_XATTR);
> set_opt(sbi, INLINE_DATA);
> set_opt(sbi, INLINE_DENTRY);
> @@ -1780,7 +1776,8 @@ static int f2fs_remount(struct super_block *sb, int *flags, char *data)
> * or if background_gc = off is passed in mount
> * option. Also sync the filesystem.
> */
> - if ((*flags & SB_RDONLY) || !test_opt(sbi, BG_GC)) {
> + if ((*flags & SB_RDONLY) ||
> + F2FS_OPTION(sbi).bggc_mode == BGGC_MODE_OFF) {
> if (sbi->gc_thread) {
> f2fs_stop_gc_thread(sbi);
> need_restart_gc = true;
> @@ -3664,7 +3661,7 @@ static int f2fs_fill_super(struct super_block *sb, void *data, int silent)
> * If filesystem is not mounted as read-only then
> * do start the gc_thread.
> */
> - if (test_opt(sbi, BG_GC) && !f2fs_readonly(sb)) {
> + if (F2FS_OPTION(sbi).bggc_mode != BGGC_MODE_OFF && !f2fs_readonly(sb)) {
> /* After POR, we can run background GC thread.*/
> err = f2fs_start_gc_thread(sbi);
> if (err)
> --
> 2.18.0.rc1