From f86186b44b4164600cce03d0d93ad48ec21fa429 Mon Sep 17 00:00:00 2001 From: Eric Sandeen Date: Tue, 28 Jun 2011 10:01:31 -0400 Subject: [PATCH] ext4: refactor duplicated block placement code I found that ext4_ext_find_goal() and ext4_find_near() share the same code for returning a coloured start block based on i_block_group. We can refactor this into a common function so that they don't diverge in the future. Thanks to adilger for suggesting the new function name. Signed-off-by: Eric Sandeen Signed-off-by: "Theodore Ts'o" --- fs/ext4/balloc.c | 48 ++++++++++++++++++++++++++++++++++++++++++++++ fs/ext4/ext4.h | 1 + fs/ext4/extents.c | 37 +---------------------------------- fs/ext4/indirect.c | 28 +-------------------------- 4 files changed, 51 insertions(+), 63 deletions(-) diff --git a/fs/ext4/balloc.c b/fs/ext4/balloc.c index 264f6949511e..f8224adf496e 100644 --- a/fs/ext4/balloc.c +++ b/fs/ext4/balloc.c @@ -620,3 +620,51 @@ unsigned long ext4_bg_num_gdb(struct super_block *sb, ext4_group_t group) } +/** + * ext4_inode_to_goal_block - return a hint for block allocation + * @inode: inode for block allocation + * + * Return the ideal location to start allocating blocks for a + * newly created inode. + */ +ext4_fsblk_t ext4_inode_to_goal_block(struct inode *inode) +{ + struct ext4_inode_info *ei = EXT4_I(inode); + ext4_group_t block_group; + ext4_grpblk_t colour; + int flex_size = ext4_flex_bg_size(EXT4_SB(inode->i_sb)); + ext4_fsblk_t bg_start; + ext4_fsblk_t last_block; + + block_group = ei->i_block_group; + if (flex_size >= EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME) { + /* + * If there are at least EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME + * block groups per flexgroup, reserve the first block + * group for directories and special files. Regular + * files will start at the second block group. This + * tends to speed up directory access and improves + * fsck times. + */ + block_group &= ~(flex_size-1); + if (S_ISREG(inode->i_mode)) + block_group++; + } + bg_start = ext4_group_first_block_no(inode->i_sb, block_group); + last_block = ext4_blocks_count(EXT4_SB(inode->i_sb)->s_es) - 1; + + /* + * If we are doing delayed allocation, we don't need take + * colour into account. + */ + if (test_opt(inode->i_sb, DELALLOC)) + return bg_start; + + if (bg_start + EXT4_BLOCKS_PER_GROUP(inode->i_sb) <= last_block) + colour = (current->pid % 16) * + (EXT4_BLOCKS_PER_GROUP(inode->i_sb) / 16); + else + colour = (current->pid % 16) * ((last_block - bg_start) / 16); + return bg_start + colour; +} + diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index ddaf5043fb38..49d2cea47382 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -1743,6 +1743,7 @@ extern unsigned ext4_init_block_bitmap(struct super_block *sb, struct ext4_group_desc *desc); #define ext4_free_blocks_after_init(sb, group, desc) \ ext4_init_block_bitmap(sb, NULL, group, desc) +ext4_fsblk_t ext4_inode_to_goal_block(struct inode *); /* dir.c */ extern int __ext4_check_dir_entry(const char *, unsigned int, struct inode *, diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c index eb63c7b8dfd2..f331e5010f68 100644 --- a/fs/ext4/extents.c +++ b/fs/ext4/extents.c @@ -114,12 +114,6 @@ static ext4_fsblk_t ext4_ext_find_goal(struct inode *inode, struct ext4_ext_path *path, ext4_lblk_t block) { - struct ext4_inode_info *ei = EXT4_I(inode); - ext4_fsblk_t bg_start; - ext4_fsblk_t last_block; - ext4_grpblk_t colour; - ext4_group_t block_group; - int flex_size = ext4_flex_bg_size(EXT4_SB(inode->i_sb)); int depth; if (path) { @@ -161,36 +155,7 @@ static ext4_fsblk_t ext4_ext_find_goal(struct inode *inode, } /* OK. use inode's group */ - block_group = ei->i_block_group; - if (flex_size >= EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME) { - /* - * If there are at least EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME - * block groups per flexgroup, reserve the first block - * group for directories and special files. Regular - * files will start at the second block group. This - * tends to speed up directory access and improves - * fsck times. - */ - block_group &= ~(flex_size-1); - if (S_ISREG(inode->i_mode)) - block_group++; - } - bg_start = ext4_group_first_block_no(inode->i_sb, block_group); - last_block = ext4_blocks_count(EXT4_SB(inode->i_sb)->s_es) - 1; - - /* - * If we are doing delayed allocation, we don't need take - * colour into account. - */ - if (test_opt(inode->i_sb, DELALLOC)) - return bg_start; - - if (bg_start + EXT4_BLOCKS_PER_GROUP(inode->i_sb) <= last_block) - colour = (current->pid % 16) * - (EXT4_BLOCKS_PER_GROUP(inode->i_sb) / 16); - else - colour = (current->pid % 16) * ((last_block - bg_start) / 16); - return bg_start + colour + block; + return ext4_inode_to_goal_block(inode); } /* diff --git a/fs/ext4/indirect.c b/fs/ext4/indirect.c index c3e85a86e821..6c271115dbb6 100644 --- a/fs/ext4/indirect.c +++ b/fs/ext4/indirect.c @@ -207,11 +207,6 @@ static ext4_fsblk_t ext4_find_near(struct inode *inode, Indirect *ind) struct ext4_inode_info *ei = EXT4_I(inode); __le32 *start = ind->bh ? (__le32 *) ind->bh->b_data : ei->i_data; __le32 *p; - ext4_fsblk_t bg_start; - ext4_fsblk_t last_block; - ext4_grpblk_t colour; - ext4_group_t block_group; - int flex_size = ext4_flex_bg_size(EXT4_SB(inode->i_sb)); /* Try to find previous block */ for (p = ind->p - 1; p >= start; p--) { @@ -227,28 +222,7 @@ static ext4_fsblk_t ext4_find_near(struct inode *inode, Indirect *ind) * It is going to be referred to from the inode itself? OK, just put it * into the same cylinder group then. */ - block_group = ei->i_block_group; - if (flex_size >= EXT4_FLEX_SIZE_DIR_ALLOC_SCHEME) { - block_group &= ~(flex_size-1); - if (S_ISREG(inode->i_mode)) - block_group++; - } - bg_start = ext4_group_first_block_no(inode->i_sb, block_group); - last_block = ext4_blocks_count(EXT4_SB(inode->i_sb)->s_es) - 1; - - /* - * If we are doing delayed allocation, we don't need take - * colour into account. - */ - if (test_opt(inode->i_sb, DELALLOC)) - return bg_start; - - if (bg_start + EXT4_BLOCKS_PER_GROUP(inode->i_sb) <= last_block) - colour = (current->pid % 16) * - (EXT4_BLOCKS_PER_GROUP(inode->i_sb) / 16); - else - colour = (current->pid % 16) * ((last_block - bg_start) / 16); - return bg_start + colour; + return ext4_inode_to_goal_block(inode); } /** -- 2.20.1