Commit c27e43a1 authored by Eric Whitney's avatar Eric Whitney Committed by Theodore Ts'o
Browse files

ext4: minor cleanup of ext4_da_reserve_space() 



Remove outdated comments and dead code from ext4_da_reserve_space.
Clean up its trace point, and relocate it to make it more useful.

While we're at it, fix a nearby conditional used to determine if
we have a non-bigalloc file system.  It doesn't match usage elsewhere
in the code, and misleadingly suggests that an s_cluster_ratio value
of 0 would be legal.

Signed-off-by: default avatarEric Whitney <enwlinux@gmail.com>
Signed-off-by: default avatarTheodore Ts'o <tytso@mit.edu>
parent 292db1bc

fs/ext4/inode.c

+5 −17
Original line number Diff line number Diff line
@@ -1261,13 +1261,12 @@ static int ext4_journalled_write_end(struct file *file, 
}



/*

 * Reserve a single cluster located at lblock

 * Reserve space for a single cluster

 */

static int ext4_da_reserve_space(struct inode *inode, ext4_lblk_t lblock)

static int ext4_da_reserve_space(struct inode *inode)

{

	struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);

	struct ext4_inode_info *ei = EXT4_I(inode);

	unsigned int md_needed;

	int ret;



	/*
@@ -1279,25 +1278,14 @@ static int ext4_da_reserve_space(struct inode *inode, ext4_lblk_t lblock) 
	if (ret)

		return ret;



	/*

	 * recalculate the amount of metadata blocks to reserve

	 * in order to allocate nrblocks

	 * worse case is one extent per block

	 */

	spin_lock(&ei->i_block_reservation_lock);

	/*

	 * ext4_calc_metadata_amount() has side effects, which we have

	 * to be prepared undo if we fail to claim space.

	 */

	md_needed = 0;

	trace_ext4_da_reserve_space(inode, 0);



	if (ext4_claim_free_clusters(sbi, 1, 0)) {

		spin_unlock(&ei->i_block_reservation_lock);

		dquot_release_reservation_block(inode, EXT4_C2B(sbi, 1));

		return -ENOSPC;

	}

	ei->i_reserved_data_blocks++;

	trace_ext4_da_reserve_space(inode);

	spin_unlock(&ei->i_block_reservation_lock);



	return 0;       /* success */
@@ -1566,9 +1554,9 @@ add_delayed: 
		 * then we don't need to reserve it again. However we still need

		 * to reserve metadata for every block we're going to write.

		 */

		if (EXT4_SB(inode->i_sb)->s_cluster_ratio <= 1 ||

		if (EXT4_SB(inode->i_sb)->s_cluster_ratio == 1 ||

		    !ext4_find_delalloc_cluster(inode, map->m_lblk)) {

			ret = ext4_da_reserve_space(inode, iblock);

			ret = ext4_da_reserve_space(inode);

			if (ret) {

				/* not enough space to reserve */

				retval = ret;

include/trace/events/ext4.h

+4 −6
Original line number Diff line number Diff line
@@ -1185,15 +1185,14 @@ TRACE_EVENT(ext4_da_update_reserve_space, 
);



TRACE_EVENT(ext4_da_reserve_space,

	TP_PROTO(struct inode *inode, int md_needed),

	TP_PROTO(struct inode *inode),



	TP_ARGS(inode, md_needed),

	TP_ARGS(inode),



	TP_STRUCT__entry(

		__field(	dev_t,	dev			)

		__field(	ino_t,	ino			)

		__field(	__u64,	i_blocks		)

		__field(	int,	md_needed		)

		__field(	int,	reserved_data_blocks	)

		__field(	int,	reserved_meta_blocks	)

		__field(	__u16,  mode			)
@@ -1203,18 +1202,17 @@ TRACE_EVENT(ext4_da_reserve_space, 
		__entry->dev	= inode->i_sb->s_dev;

		__entry->ino	= inode->i_ino;

		__entry->i_blocks = inode->i_blocks;

		__entry->md_needed = md_needed;

		__entry->reserved_data_blocks = EXT4_I(inode)->i_reserved_data_blocks;

		__entry->reserved_meta_blocks = EXT4_I(inode)->i_reserved_meta_blocks;

		__entry->mode	= inode->i_mode;

	),



	TP_printk("dev %d,%d ino %lu mode 0%o i_blocks %llu md_needed %d "

	TP_printk("dev %d,%d ino %lu mode 0%o i_blocks %llu "

		  "reserved_data_blocks %d reserved_meta_blocks %d",

		  MAJOR(__entry->dev), MINOR(__entry->dev),

		  (unsigned long) __entry->ino,

		  __entry->mode, __entry->i_blocks,

		  __entry->md_needed, __entry->reserved_data_blocks,

		  __entry->reserved_data_blocks,

		  __entry->reserved_meta_blocks)

);

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