From 6aea6f5068cb86e89a6ac243c3fc131045b6563a Mon Sep 17 00:00:00 2001 From: Tristan Ye Date: Fri, 27 May 2011 15:19:56 +0800 Subject: Ocfs2/move_extents: Avoid doing division in extent moving. It's not wise enough to do a 64bits division anywhere in kernside, replace it with a decent helper or proper shifts. Signed-off-by: Tristan Ye --- fs/ocfs2/move_extents.c | 19 +++++++++---------- 1 file changed, 9 insertions(+), 10 deletions(-) diff --git a/fs/ocfs2/move_extents.c b/fs/ocfs2/move_extents.c index 4c54884..d184e0b 100644 --- a/fs/ocfs2/move_extents.c +++ b/fs/ocfs2/move_extents.c @@ -368,7 +368,7 @@ static int ocfs2_find_victim_alloc_group(struct inode *inode, int *vict_bit, struct buffer_head **ret_bh) { - int ret, i, blocks_per_unit = 1; + int ret, i, bits_per_unit = 0; u64 blkno; char namebuf[40]; @@ -398,14 +398,14 @@ static int ocfs2_find_victim_alloc_group(struct inode *inode, rec = &(cl->cl_recs[0]); if (type == GLOBAL_BITMAP_SYSTEM_INODE) - blocks_per_unit <<= (osb->s_clustersize_bits - - inode->i_sb->s_blocksize_bits); + bits_per_unit = osb->s_clustersize_bits - + inode->i_sb->s_blocksize_bits; /* * 'vict_blkno' was out of the valid range. */ if ((vict_blkno < le64_to_cpu(rec->c_blkno)) || - (vict_blkno >= (le32_to_cpu(ac_dinode->id1.bitmap1.i_total) * - blocks_per_unit))) { + (vict_blkno >= (le32_to_cpu(ac_dinode->id1.bitmap1.i_total) << + bits_per_unit))) { ret = -EINVAL; goto out; } @@ -441,8 +441,8 @@ static int ocfs2_find_victim_alloc_group(struct inode *inode, le16_to_cpu(bg->bg_bits))) { *ret_bh = gd_bh; - *vict_bit = (vict_blkno - blkno) / - blocks_per_unit; + *vict_bit = (vict_blkno - blkno) >> + bits_per_unit; mlog(0, "find the victim group: #%llu, " "total_bits: %u, vict_bit: %u\n", blkno, le16_to_cpu(bg->bg_bits), @@ -493,9 +493,8 @@ static int ocfs2_validate_and_adjust_move_goal(struct inode *inode, /* * make goal become cluster aligned. */ - if (range->me_goal % c_to_b) - range->me_goal = range->me_goal / c_to_b * c_to_b; - + range->me_goal = ocfs2_block_to_cluster_start(inode->i_sb, + range->me_goal); /* * moving goal is not allowd to start with a group desc blok(#0 blk) * let's compromise to the latter cluster. -- cgit v1.1 From ea5e1675ac832b42889ac8d254ea8fbfbdfaa8b2 Mon Sep 17 00:00:00 2001 From: Tristan Ye Date: Fri, 27 May 2011 15:24:14 +0800 Subject: Ocfs2/move_extents: Validate moving goal after the adjustment. though the goal_to_be_moved will be validated again in following moving, it's still a good idea to validate it after adjustment at the very beginning, instead of validating it before adjustment. Signed-off-by: Tristan Ye --- fs/ocfs2/move_extents.c | 26 +++++++++++++------------- 1 file changed, 13 insertions(+), 13 deletions(-) diff --git a/fs/ocfs2/move_extents.c b/fs/ocfs2/move_extents.c index d184e0b..cd94270 100644 --- a/fs/ocfs2/move_extents.c +++ b/fs/ocfs2/move_extents.c @@ -472,12 +472,24 @@ static int ocfs2_validate_and_adjust_move_goal(struct inode *inode, int ret, goal_bit = 0; struct buffer_head *gd_bh = NULL; - struct ocfs2_group_desc *bg; + struct ocfs2_group_desc *bg = NULL; struct ocfs2_super *osb = OCFS2_SB(inode->i_sb); int c_to_b = 1 << (osb->s_clustersize_bits - inode->i_sb->s_blocksize_bits); /* + * make goal become cluster aligned. + */ + range->me_goal = ocfs2_block_to_cluster_start(inode->i_sb, + range->me_goal); + /* + * moving goal is not allowd to start with a group desc blok(#0 blk) + * let's compromise to the latter cluster. + */ + if (range->me_goal == le64_to_cpu(bg->bg_blkno)) + range->me_goal += c_to_b; + + /* * validate goal sits within global_bitmap, and return the victim * group desc */ @@ -491,18 +503,6 @@ static int ocfs2_validate_and_adjust_move_goal(struct inode *inode, bg = (struct ocfs2_group_desc *)gd_bh->b_data; /* - * make goal become cluster aligned. - */ - range->me_goal = ocfs2_block_to_cluster_start(inode->i_sb, - range->me_goal); - /* - * moving goal is not allowd to start with a group desc blok(#0 blk) - * let's compromise to the latter cluster. - */ - if (range->me_goal == le64_to_cpu(bg->bg_blkno)) - range->me_goal += c_to_b; - - /* * movement is not gonna cross two groups. */ if ((le16_to_cpu(bg->bg_bits) - goal_bit) * osb->s_clustersize < -- cgit v1.1