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Message-ID: <0c36cfba-f8b8-b899-95db-09ce5b0a8e8a@kernel.org>
Date:   Fri, 9 Dec 2022 09:31:50 +0800
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Subject: Re: [f2fs-dev] [PATCH 1/6] f2fs: specify extent cache for read
 explicitly
To:     Jaegeuk Kim <jaegeuk@kernel.org>
Cc:     linux-kernel@vger.kernel.org,
        linux-f2fs-devel@lists.sourceforge.net
References: <20221205185433.3479699-1-jaegeuk@kernel.org>
 <8ffb43dd-3887-aa56-6f0a-1fb6ff0e191e@kernel.org>
 <Y5IfEkHlpZ0oBRID@google.com>
Content-Language: en-US
From:   Chao Yu <chao@kernel.org>
In-Reply-To: <Y5IfEkHlpZ0oBRID@google.com>
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On 2022/12/9 1:29, Jaegeuk Kim wrote:
> On 12/08, Chao Yu wrote:
>> On 2022/12/6 2:54, Jaegeuk Kim wrote:
>>> Let's descrbie it's read extent cache.
>>>
>>> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
>>> ---
>>>    fs/f2fs/extent_cache.c |  4 ++--
>>>    fs/f2fs/f2fs.h         | 10 +++++-----
>>>    fs/f2fs/inode.c        |  2 +-
>>>    fs/f2fs/node.c         |  2 +-
>>>    fs/f2fs/node.h         |  2 +-
>>>    fs/f2fs/segment.c      |  4 ++--
>>>    fs/f2fs/super.c        | 16 ++++++++--------
>>>    7 files changed, 20 insertions(+), 20 deletions(-)
>>>
>>> diff --git a/fs/f2fs/extent_cache.c b/fs/f2fs/extent_cache.c
>>> index 932c070173b9..8cd87aee0292 100644
>>> --- a/fs/f2fs/extent_cache.c
>>> +++ b/fs/f2fs/extent_cache.c
>>> @@ -383,7 +383,7 @@ static void __f2fs_init_extent_tree(struct inode *inode, struct page *ipage)
>>>    	if (!i_ext || !i_ext->len)
>>>    		return;
>>> -	get_extent_info(&ei, i_ext);
>>> +	get_read_extent_info(&ei, i_ext);
>>>    	write_lock(&et->lock);
>>>    	if (atomic_read(&et->node_cnt))
>>> @@ -710,7 +710,7 @@ unsigned int f2fs_shrink_extent_tree(struct f2fs_sb_info *sbi, int nr_shrink)
>>>    	unsigned int node_cnt = 0, tree_cnt = 0;
>>>    	int remained;
>>> -	if (!test_opt(sbi, EXTENT_CACHE))
>>> +	if (!test_opt(sbi, READ_EXTENT_CACHE))
>>>    		return 0;
>>>    	if (!atomic_read(&sbi->total_zombie_tree))
>>> diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
>>> index eb8c27c4e5fc..1c39f8145b61 100644
>>> --- a/fs/f2fs/f2fs.h
>>> +++ b/fs/f2fs/f2fs.h
>>> @@ -92,7 +92,7 @@ extern const char *f2fs_fault_name[FAULT_MAX];
>>>    #define F2FS_MOUNT_FLUSH_MERGE		0x00000400
>>>    #define F2FS_MOUNT_NOBARRIER		0x00000800
>>>    #define F2FS_MOUNT_FASTBOOT		0x00001000
>>> -#define F2FS_MOUNT_EXTENT_CACHE		0x00002000
>>> +#define F2FS_MOUNT_READ_EXTENT_CACHE	0x00002000
>>>    #define F2FS_MOUNT_DATA_FLUSH		0x00008000
>>>    #define F2FS_MOUNT_FAULT_INJECTION	0x00010000
>>>    #define F2FS_MOUNT_USRQUOTA		0x00080000
>>> @@ -600,7 +600,7 @@ enum {
>>>    #define F2FS_MIN_EXTENT_LEN	64	/* minimum extent length */
>>>    /* number of extent info in extent cache we try to shrink */
>>> -#define EXTENT_CACHE_SHRINK_NUMBER	128
>>> +#define READ_EXTENT_CACHE_SHRINK_NUMBER	128
>>>    #define RECOVERY_MAX_RA_BLOCKS		BIO_MAX_VECS
>>>    #define RECOVERY_MIN_RA_BLOCKS		1
>>> @@ -830,7 +830,7 @@ struct f2fs_inode_info {
>>>    	loff_t original_i_size;		/* original i_size before atomic write */
>>>    };
>>> -static inline void get_extent_info(struct extent_info *ext,
>>> +static inline void get_read_extent_info(struct extent_info *ext,
>>>    					struct f2fs_extent *i_ext)
>>>    {
>>>    	ext->fofs = le32_to_cpu(i_ext->fofs);
>>> @@ -838,7 +838,7 @@ static inline void get_extent_info(struct extent_info *ext,
>>>    	ext->len = le32_to_cpu(i_ext->len);
>>>    }
>>> -static inline void set_raw_extent(struct extent_info *ext,
>>> +static inline void set_raw_read_extent(struct extent_info *ext,
>>>    					struct f2fs_extent *i_ext)
>>>    {
>>>    	i_ext->fofs = cpu_to_le32(ext->fofs);
>>> @@ -4407,7 +4407,7 @@ static inline bool f2fs_may_extent_tree(struct inode *inode)
>>>    {
>>>    	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
>>> -	if (!test_opt(sbi, EXTENT_CACHE) ||
>>> +	if (!test_opt(sbi, READ_EXTENT_CACHE) ||
>>>    			is_inode_flag_set(inode, FI_NO_EXTENT) ||
>>>    			(is_inode_flag_set(inode, FI_COMPRESSED_FILE) &&
>>>    			 !f2fs_sb_has_readonly(sbi)))
>>> diff --git a/fs/f2fs/inode.c b/fs/f2fs/inode.c
>>> index 577f109b4e1d..2c705c60019b 100644
>>> --- a/fs/f2fs/inode.c
>>> +++ b/fs/f2fs/inode.c
>>> @@ -629,7 +629,7 @@ void f2fs_update_inode(struct inode *inode, struct page *node_page)
>>>    	if (et) {
>>>    		read_lock(&et->lock);
>>> -		set_raw_extent(&et->largest, &ri->i_ext);
>>> +		set_raw_read_extent(&et->largest, &ri->i_ext);
>>>    		read_unlock(&et->lock);
>>>    	} else {
>>>    		memset(&ri->i_ext, 0, sizeof(ri->i_ext));
>>> diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
>>> index b9ee5a1176a0..84b147966080 100644
>>> --- a/fs/f2fs/node.c
>>> +++ b/fs/f2fs/node.c
>>> @@ -85,7 +85,7 @@ bool f2fs_available_free_memory(struct f2fs_sb_info *sbi, int type)
>>>    						sizeof(struct ino_entry);
>>>    		mem_size >>= PAGE_SHIFT;
>>>    		res = mem_size < ((avail_ram * nm_i->ram_thresh / 100) >> 1);
>>> -	} else if (type == EXTENT_CACHE) {
>>> +	} else if (type == READ_EXTENT_CACHE) {
>>>    		mem_size = (atomic_read(&sbi->total_ext_tree) *
>>>    				sizeof(struct extent_tree) +
>>>    				atomic_read(&sbi->total_ext_node) *
>>> diff --git a/fs/f2fs/node.h b/fs/f2fs/node.h
>>> index 3c09cae058b0..0aa48704c77a 100644
>>> --- a/fs/f2fs/node.h
>>> +++ b/fs/f2fs/node.h
>>> @@ -146,7 +146,7 @@ enum mem_type {
>>>    	NAT_ENTRIES,	/* indicates the cached nat entry */
>>>    	DIRTY_DENTS,	/* indicates dirty dentry pages */
>>>    	INO_ENTRIES,	/* indicates inode entries */
>>> -	EXTENT_CACHE,	/* indicates extent cache */
>>> +	READ_EXTENT_CACHE,	/* indicates read extent cache */
>>>    	DISCARD_CACHE,	/* indicates memory of cached discard cmds */
>>>    	COMPRESS_PAGE,	/* indicates memory of cached compressed pages */
>>>    	BASE_CHECK,	/* check kernel status */
>>> diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
>>> index 9486ca49ecb1..51de358bc452 100644
>>> --- a/fs/f2fs/segment.c
>>> +++ b/fs/f2fs/segment.c
>>> @@ -449,8 +449,8 @@ void f2fs_balance_fs_bg(struct f2fs_sb_info *sbi, bool from_bg)
>>>    		return;
>>>    	/* try to shrink extent cache when there is no enough memory */
>>> -	if (!f2fs_available_free_memory(sbi, EXTENT_CACHE))
>>> -		f2fs_shrink_extent_tree(sbi, EXTENT_CACHE_SHRINK_NUMBER);
>>> +	if (!f2fs_available_free_memory(sbi, READ_EXTENT_CACHE))
>>> +		f2fs_shrink_extent_tree(sbi, READ_EXTENT_CACHE_SHRINK_NUMBER);
>>>    	/* check the # of cached NAT entries */
>>>    	if (!f2fs_available_free_memory(sbi, NAT_ENTRIES))
>>> diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
>>> index 79bf1faf4161..10bd03bbefec 100644
>>> --- a/fs/f2fs/super.c
>>> +++ b/fs/f2fs/super.c
>>> @@ -814,10 +814,10 @@ static int parse_options(struct super_block *sb, char *options, bool is_remount)
>>>    			set_opt(sbi, FASTBOOT);
>>>    			break;
>>>    		case Opt_extent_cache:
>>> -			set_opt(sbi, EXTENT_CACHE);
>>> +			set_opt(sbi, READ_EXTENT_CACHE);
>>>    			break;
>>>    		case Opt_noextent_cache:
>>> -			clear_opt(sbi, EXTENT_CACHE);
>>> +			clear_opt(sbi, READ_EXTENT_CACHE);
>>>    			break;
>>>    		case Opt_noinline_data:
>>>    			clear_opt(sbi, INLINE_DATA);
>>> @@ -1954,10 +1954,10 @@ static int f2fs_show_options(struct seq_file *seq, struct dentry *root)
>>>    		seq_puts(seq, ",barrier");
>>>    	if (test_opt(sbi, FASTBOOT))
>>>    		seq_puts(seq, ",fastboot");
>>> -	if (test_opt(sbi, EXTENT_CACHE))
>>> -		seq_puts(seq, ",extent_cache");
>>> +	if (test_opt(sbi, READ_EXTENT_CACHE))
>>> +		seq_puts(seq, ",read_extent_cache");
>>
>> How about keeping consistent w/ description of f2fs.rst?
> 
> This doesn't change the mount options, but do show the exact name which
> would be better to say what's going on.

mount -t f2fs /dev/vda /mnt/f2fs
mount|grep f2fs
/dev/vda on /mnt/f2fs type f2fs (rw,relatime,lazytime,background_gc=on,discard,no_heap,user_xattr,inline_xattr,acl,inline_data,inline_dentry,flush_merge,barrier,read_extent_cache,mode=adaptive,active_logs=6,alloc_mode=reuse,check)

mount -t f2fs -o remount /mnt/f2fs/
[   63.142480] F2FS-fs (vda): Unrecognized mount option "read_extent_cache" or missing value

Quoted from manual of mount

"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 is found in fstab, then a
remount with unspecified source is allowed."

I guess above command tries to use previous mountoptions which were read
via .show_options().

Thanks,

> 
>>
>>>    	else
>>> -		seq_puts(seq, ",noextent_cache");
>>> +		seq_puts(seq, ",no_read_extent_cache");
>>
>> Ditto,
>>
>> Thanks,
>>
>>>    	if (test_opt(sbi, DATA_FLUSH))
>>>    		seq_puts(seq, ",data_flush");
>>> @@ -2076,7 +2076,7 @@ static void default_options(struct f2fs_sb_info *sbi)
>>>    	set_opt(sbi, INLINE_XATTR);
>>>    	set_opt(sbi, INLINE_DATA);
>>>    	set_opt(sbi, INLINE_DENTRY);
>>> -	set_opt(sbi, EXTENT_CACHE);
>>> +	set_opt(sbi, READ_EXTENT_CACHE);
>>>    	set_opt(sbi, NOHEAP);
>>>    	clear_opt(sbi, DISABLE_CHECKPOINT);
>>>    	set_opt(sbi, MERGE_CHECKPOINT);
>>> @@ -2218,7 +2218,7 @@ static int f2fs_remount(struct super_block *sb, int *flags, char *data)
>>>    	bool need_restart_ckpt = false, need_stop_ckpt = false;
>>>    	bool need_restart_flush = false, need_stop_flush = false;
>>>    	bool need_restart_discard = false, need_stop_discard = false;
>>> -	bool no_extent_cache = !test_opt(sbi, EXTENT_CACHE);
>>> +	bool no_read_extent_cache = !test_opt(sbi, READ_EXTENT_CACHE);
>>>    	bool enable_checkpoint = !test_opt(sbi, DISABLE_CHECKPOINT);
>>>    	bool no_io_align = !F2FS_IO_ALIGNED(sbi);
>>>    	bool no_atgc = !test_opt(sbi, ATGC);
>>> @@ -2308,7 +2308,7 @@ static int f2fs_remount(struct super_block *sb, int *flags, char *data)
>>>    	}
>>>    	/* disallow enable/disable extent_cache dynamically */
>>> -	if (no_extent_cache == !!test_opt(sbi, EXTENT_CACHE)) {
>>> +	if (no_read_extent_cache == !!test_opt(sbi, READ_EXTENT_CACHE)) {
>>>    		err = -EINVAL;
>>>    		f2fs_warn(sbi, "switch extent_cache option is not allowed");
>>>    		goto restore_opts;