Commit 304749c0 authored by Ojaswin Mujoo's avatar Ojaswin Mujoo Committed by Theodore Ts'o
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ext4: replace CR_FAST macro with inline function for readability 



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: default avatarOjaswin Mujoo <ojaswin@linux.ibm.com>
Reviewed-by: default avatarJan Kara <jack@suse.cz>
Reviewed-by: default avatarRitesh Harjani (IBM) <ritesh.list@gmail.com>
Link: https://lore.kernel.org/r/20230630085927.140137-1-ojaswin@linux.ibm.com


Signed-off-by: default avatarTheodore Ts'o <tytso@mit.edu>
parent 1e1566b9

fs/ext4/ext4.h

+4 −3
Original line number Diff line number Diff line
@@ -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,

fs/ext4/mballoc.c

+9 −4
Original line number Diff line number Diff line
@@ -2450,7 +2450,7 @@ 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
@@ -2634,7 +2634,12 @@ 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;
@@ -2658,7 +2663,7 @@ 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) &&
@@ -2852,7 +2857,7 @@ 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)) {