>From 9e09fef78b2fa552c883bf8124af873abfde0805 Mon Sep 17 00:00:00 2001
From: Lokesh Nagappa Jaliminche <lokesh.jaliminche@xxxxxxxxxxx>
Added a check at the start of group search loop to
avoid looping unecessarily in case of empty group.
This also allow group search to jump directly to
"found_flex_bg" with "stats" and "group" already set,
so there is no need to go through the extra steps of
setting "best_desc" and "best_group" and then break
out of the loop just to set "stats" and "group" again.
Signed-off-by: Lokesh N Jaliminche <lokesh.jaliminche@xxxxxxxxx>
---
fs/ext4/ialloc.c | 8 ++++++++
1 files changed, 8 insertions(+), 0 deletions(-)
diff --git a/fs/ext4/ialloc.c b/fs/ext4/ialloc.c
index 1b8024d..588bf8e 100644
--- a/fs/ext4/ialloc.c
+++ b/fs/ext4/ialloc.c
@@ -446,6 +446,8 @@ static int find_group_orlov(struct super_block
*sb, struct inode *parent,
struct ext4_sb_info *sbi = EXT4_SB(sb);
ext4_group_t real_ngroups = ext4_get_groups_count(sb);
int inodes_per_group = EXT4_INODES_PER_GROUP(sb);
+ unsigned int inodes_per_flex_group;
+ long unsigned int blocks_per_clustre;
unsigned int freei, avefreei, grp_free;
ext4_fsblk_t freeb, avefreec;
unsigned int ndirs;
@@ -470,6 +472,8 @@ static int find_group_orlov(struct super_block
*sb, struct inode *parent,
percpu_counter_read_positive(&sbi->s_freeclusters_counter));
avefreec = freeb;
do_div(avefreec, ngroups);
+ inodes_per_flex_group = inodes_per_group * flex_size;
+ blocks_per_clustre = sbi->s_blocks_per_group * flex_size;
ndirs = percpu_counter_read_positive(&sbi->s_dirs_counter);
if (S_ISDIR(mode) &&
@@ -489,6 +493,10 @@ static int find_group_orlov(struct super_block
*sb, struct inode *parent,
for (i = 0; i < ngroups; i++) {
g = (parent_group + i) % ngroups;
get_orlov_stats(sb, g, flex_size, &stats);
+ /* the group can't get any better than empty */
+ if (inodes_per_flex_group == stats.free_inodes &&
+ blocks_per_clustre == stats.free_clusters)
+ goto found_flex_bg;
if (!stats.free_inodes)
continue;
if (stats.used_dirs >= best_ndir)
--
1.7.1
Attachment:
0001-EXT4-optimizing-group-serch-for-inode-allocation.patch
Description: Binary data
