Change some variable names to be more consistent and refactor some of the code to make it easier to read. There are no functional changes in this patch Signed-off-by: Ojaswin Mujoo <ojaswin@xxxxxxxxxxxxx> Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@xxxxxxxxx> --- fs/ext4/mballoc.c | 97 ++++++++++++++++++++++++----------------------- 1 file changed, 49 insertions(+), 48 deletions(-) diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index 8be6f8765a6f..84950df709bb 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -4000,7 +4000,8 @@ ext4_mb_normalize_request(struct ext4_allocation_context *ac, loff_t orig_size __maybe_unused; ext4_lblk_t start; struct ext4_inode_info *ei = EXT4_I(ac->ac_inode); - struct ext4_prealloc_space *pa; + struct ext4_prealloc_space *tmp_pa; + ext4_lblk_t tmp_pa_start, tmp_pa_end; /* do normalize only data requests, metadata requests do not need preallocation */ @@ -4103,56 +4104,53 @@ ext4_mb_normalize_request(struct ext4_allocation_context *ac, /* check we don't cross already preallocated blocks */ rcu_read_lock(); - list_for_each_entry_rcu(pa, &ei->i_prealloc_list, pa_inode_list) { - ext4_lblk_t pa_end; - - if (pa->pa_deleted) + list_for_each_entry_rcu(tmp_pa, &ei->i_prealloc_list, pa_inode_list) { + if (tmp_pa->pa_deleted) continue; - spin_lock(&pa->pa_lock); - if (pa->pa_deleted) { - spin_unlock(&pa->pa_lock); + spin_lock(&tmp_pa->pa_lock); + if (tmp_pa->pa_deleted) { + spin_unlock(&tmp_pa->pa_lock); continue; } - pa_end = pa->pa_lstart + EXT4_C2B(EXT4_SB(ac->ac_sb), - pa->pa_len); + tmp_pa_start = tmp_pa->pa_lstart; + tmp_pa_end = tmp_pa->pa_lstart + EXT4_C2B(sbi, tmp_pa->pa_len); /* PA must not overlap original request */ - BUG_ON(!(ac->ac_o_ex.fe_logical >= pa_end || - ac->ac_o_ex.fe_logical < pa->pa_lstart)); + BUG_ON(!(ac->ac_o_ex.fe_logical >= tmp_pa_end || + ac->ac_o_ex.fe_logical < tmp_pa_start)); /* skip PAs this normalized request doesn't overlap with */ - if (pa->pa_lstart >= end || pa_end <= start) { - spin_unlock(&pa->pa_lock); + if (tmp_pa_start >= end || tmp_pa_end <= start) { + spin_unlock(&tmp_pa->pa_lock); continue; } - BUG_ON(pa->pa_lstart <= start && pa_end >= end); + BUG_ON(tmp_pa_start <= start && tmp_pa_end >= end); /* adjust start or end to be adjacent to this pa */ - if (pa_end <= ac->ac_o_ex.fe_logical) { - BUG_ON(pa_end < start); - start = pa_end; - } else if (pa->pa_lstart > ac->ac_o_ex.fe_logical) { - BUG_ON(pa->pa_lstart > end); - end = pa->pa_lstart; + if (tmp_pa_end <= ac->ac_o_ex.fe_logical) { + BUG_ON(tmp_pa_end < start); + start = tmp_pa_end; + } else if (tmp_pa_start > ac->ac_o_ex.fe_logical) { + BUG_ON(tmp_pa_start > end); + end = tmp_pa_start; } - spin_unlock(&pa->pa_lock); + spin_unlock(&tmp_pa->pa_lock); } rcu_read_unlock(); size = end - start; /* XXX: extra loop to check we really don't overlap preallocations */ rcu_read_lock(); - list_for_each_entry_rcu(pa, &ei->i_prealloc_list, pa_inode_list) { - ext4_lblk_t pa_end; + list_for_each_entry_rcu(tmp_pa, &ei->i_prealloc_list, pa_inode_list) { + spin_lock(&tmp_pa->pa_lock); + if (tmp_pa->pa_deleted == 0) { + tmp_pa_start = tmp_pa->pa_lstart; + tmp_pa_end = tmp_pa->pa_lstart + EXT4_C2B(sbi, tmp_pa->pa_len); - spin_lock(&pa->pa_lock); - if (pa->pa_deleted == 0) { - pa_end = pa->pa_lstart + EXT4_C2B(EXT4_SB(ac->ac_sb), - pa->pa_len); - BUG_ON(!(start >= pa_end || end <= pa->pa_lstart)); + BUG_ON(!(start >= tmp_pa_end || end <= tmp_pa_start)); } - spin_unlock(&pa->pa_lock); + spin_unlock(&tmp_pa->pa_lock); } rcu_read_unlock(); @@ -4362,7 +4360,8 @@ ext4_mb_use_preallocated(struct ext4_allocation_context *ac) int order, i; struct ext4_inode_info *ei = EXT4_I(ac->ac_inode); struct ext4_locality_group *lg; - struct ext4_prealloc_space *pa, *cpa = NULL; + struct ext4_prealloc_space *tmp_pa, *cpa = NULL; + ext4_lblk_t tmp_pa_start, tmp_pa_end; ext4_fsblk_t goal_block; /* only data can be preallocated */ @@ -4371,18 +4370,20 @@ ext4_mb_use_preallocated(struct ext4_allocation_context *ac) /* first, try per-file preallocation */ rcu_read_lock(); - list_for_each_entry_rcu(pa, &ei->i_prealloc_list, pa_inode_list) { + list_for_each_entry_rcu(tmp_pa, &ei->i_prealloc_list, pa_inode_list) { /* all fields in this condition don't change, * so we can skip locking for them */ - if (ac->ac_o_ex.fe_logical < pa->pa_lstart || - ac->ac_o_ex.fe_logical >= (pa->pa_lstart + - EXT4_C2B(sbi, pa->pa_len))) + tmp_pa_start = tmp_pa->pa_lstart; + tmp_pa_end = tmp_pa->pa_lstart + EXT4_C2B(sbi, tmp_pa->pa_len); + + if (ac->ac_o_ex.fe_logical < tmp_pa_start || + ac->ac_o_ex.fe_logical >= tmp_pa_end) continue; /* non-extent files can't have physical blocks past 2^32 */ if (!(ext4_test_inode_flag(ac->ac_inode, EXT4_INODE_EXTENTS)) && - (pa->pa_pstart + EXT4_C2B(sbi, pa->pa_len) > + (tmp_pa->pa_pstart + EXT4_C2B(sbi, tmp_pa->pa_len) > EXT4_MAX_BLOCK_FILE_PHYS)) { /* * Since PAs don't overlap, we won't find any @@ -4392,16 +4393,16 @@ ext4_mb_use_preallocated(struct ext4_allocation_context *ac) } /* found preallocated blocks, use them */ - spin_lock(&pa->pa_lock); - if (pa->pa_deleted == 0 && pa->pa_free) { - atomic_inc(&pa->pa_count); - ext4_mb_use_inode_pa(ac, pa); - spin_unlock(&pa->pa_lock); + spin_lock(&tmp_pa->pa_lock); + if (tmp_pa->pa_deleted == 0 && tmp_pa->pa_free) { + atomic_inc(&tmp_pa->pa_count); + ext4_mb_use_inode_pa(ac, tmp_pa); + spin_unlock(&tmp_pa->pa_lock); ac->ac_criteria = 10; rcu_read_unlock(); return true; } - spin_unlock(&pa->pa_lock); + spin_unlock(&tmp_pa->pa_lock); } rcu_read_unlock(); @@ -4425,16 +4426,16 @@ ext4_mb_use_preallocated(struct ext4_allocation_context *ac) */ for (i = order; i < PREALLOC_TB_SIZE; i++) { rcu_read_lock(); - list_for_each_entry_rcu(pa, &lg->lg_prealloc_list[i], + list_for_each_entry_rcu(tmp_pa, &lg->lg_prealloc_list[i], pa_inode_list) { - spin_lock(&pa->pa_lock); - if (pa->pa_deleted == 0 && - pa->pa_free >= ac->ac_o_ex.fe_len) { + spin_lock(&tmp_pa->pa_lock); + if (tmp_pa->pa_deleted == 0 && + tmp_pa->pa_free >= ac->ac_o_ex.fe_len) { cpa = ext4_mb_check_group_pa(goal_block, - pa, cpa); + tmp_pa, cpa); } - spin_unlock(&pa->pa_lock); + spin_unlock(&tmp_pa->pa_lock); } rcu_read_unlock(); } -- 2.31.1