Replace CR_FAST with ext4_mb_cr_expensive() inline function for better readability. This function returns true if the criteria is one of the expensive/slower ones where lots of disk IO/prefetching is acceptable. No functional changes are intended in this patch. Signed-off-by: Ojaswin Mujoo <ojaswin@xxxxxxxxxxxxx> Reviewed-by: Jan Kara <jack@xxxxxxx> --- Changes since v1 [1] * reworded an if condition in ext_mb_good_group_nolock and added a comment to better describe the intent of the condition * Picked up RVB from Jan. [1] https://lore.kernel.org/linux-ext4/ZJ2YIr5EVbz4ezIc@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx/T/#ma9428de15c4084937274f4d66dcd4d53f505d32a fs/ext4/ext4.h | 7 ++++--- fs/ext4/mballoc.c | 13 +++++++++---- 2 files changed, 13 insertions(+), 7 deletions(-) diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index 45a531446ea2..e404169a2858 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -176,9 +176,6 @@ enum criteria { EXT4_MB_NUM_CRS }; -/* criteria below which we use fast block scanning and avoid unnecessary IO */ -#define CR_FAST CR_GOAL_LEN_SLOW - /* * Flags used in mballoc's allocation_context flags field. * @@ -2924,6 +2921,10 @@ extern int ext4_trim_fs(struct super_block *, struct fstrim_range *); extern void ext4_process_freed_data(struct super_block *sb, tid_t commit_tid); extern void ext4_mb_mark_bb(struct super_block *sb, ext4_fsblk_t block, int len, int state); +static inline bool ext4_mb_cr_expensive(enum criteria cr) +{ + return cr >= CR_GOAL_LEN_SLOW; +} /* inode.c */ void ext4_inode_csum_set(struct inode *inode, struct ext4_inode *raw, diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index a2475b8c9fb5..542577f621c6 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -2446,7 +2446,7 @@ void ext4_mb_complex_scan_group(struct ext4_allocation_context *ac, break; } - if (ac->ac_criteria < CR_FAST) { + if (!ext4_mb_cr_expensive(ac->ac_criteria)) { /* * In CR_GOAL_LEN_FAST and CR_BEST_AVAIL_LEN, we are * sure that this group will have a large enough @@ -2630,7 +2630,12 @@ static int ext4_mb_good_group_nolock(struct ext4_allocation_context *ac, free = grp->bb_free; if (free == 0) goto out; - if (cr <= CR_FAST && free < ac->ac_g_ex.fe_len) + /* + * In all criterias except CR_ANY_FREE we try to avoid groups that + * can't possibly satisfy the full goal request due to insufficient + * free blocks. + */ + if (cr < CR_ANY_FREE && free < ac->ac_g_ex.fe_len) goto out; if (unlikely(EXT4_MB_GRP_BBITMAP_CORRUPT(grp))) goto out; @@ -2654,7 +2659,7 @@ static int ext4_mb_good_group_nolock(struct ext4_allocation_context *ac, * sure we locate metadata blocks in the first block group in * the flex_bg if possible. */ - if (cr < CR_FAST && + if (!ext4_mb_cr_expensive(cr) && (!sbi->s_log_groups_per_flex || ((group & ((1 << sbi->s_log_groups_per_flex) - 1)) != 0)) && !(ext4_has_group_desc_csum(sb) && @@ -2848,7 +2853,7 @@ ext4_mb_regular_allocator(struct ext4_allocation_context *ac) * spend a lot of time loading imperfect groups */ if ((prefetch_grp == group) && - (cr >= CR_FAST || + (ext4_mb_cr_expensive(cr) || prefetch_ios < sbi->s_mb_prefetch_limit)) { nr = sbi->s_mb_prefetch; if (ext4_has_feature_flex_bg(sb)) { -- 2.31.1
