cond_resched-in-work-heavy-group-loops

   1 ext4: cond_resched in work-heavy group loops
   2
   3 From: Khazhismel Kumykov <khazhy@google.com>
   4
   5 Signed-off-by: Khazhismel Kumykov <khazhy@google.com>
   6 Signed-off-by: Theodore Ts'o <tytso@mit.edu>
   7 Reviewed-by: Andreas Dilger <adilger@dilger.ca>
   8 ---
   9 v2:
  10  - a few other places that in testing showed to be slow
  11
  12  fs/ext4/block_validity.c | 1 +
  13  fs/ext4/mballoc.c        | 2 ++
  14  2 files changed, 3 insertions(+)
  15
  16 diff --git a/fs/ext4/block_validity.c b/fs/ext4/block_validity.c
  17 index 913061c0de1b..16134469ea3c 100644
  18 --- a/fs/ext4/block_validity.c
  19 +++ b/fs/ext4/block_validity.c
  20 @@ -155,6 +155,7 @@ int ext4_setup_system_zone(struct super_block *sb)
  21                 return 0;
  22
  23         for (i=0; i < ngroups; i++) {
  24 +               cond_resched();
  25                 if (ext4_bg_has_super(sb, i) &&
  26                     ((i < 5) || ((i % flex_size) == 0)))
  27                         add_system_zone(sbi, ext4_group_first_block_no(sb, i),
  28 diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
  29 index 8ef5f12bbee2..99ba720dbb7a 100644
  30 --- a/fs/ext4/mballoc.c
  31 +++ b/fs/ext4/mballoc.c
  32 @@ -2490,6 +2490,7 @@ static int ext4_mb_init_backend(struct super_block *sb)
  33         sbi->s_buddy_cache->i_ino = EXT4_BAD_INO;
  34         EXT4_I(sbi->s_buddy_cache)->i_disksize = 0;
  35         for (i = 0; i < ngroups; i++) {
  36 +               cond_resched();
  37                 desc = ext4_get_group_desc(sb, i, NULL);
  38                 if (desc == NULL) {
  39                         ext4_msg(sb, KERN_ERR, "can't read descriptor %u", i);
  40 @@ -2705,6 +2706,7 @@ int ext4_mb_release(struct super_block *sb)
  41
  42         if (sbi->s_group_info) {
  43                 for (i = 0; i < ngroups; i++) {
  44 +                       cond_resched();
  45                         grinfo = ext4_get_group_info(sb, i);
  46  #ifdef DOUBLE_CHECK
  47                         kfree(grinfo->bb_bitmap);
  48 --
  49 2.21.0.593.g511ec345e18-goog
  50
  51