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| author | Curt Wohlgemuth <curtw@google.com> | 2009-05-01 20:27:20 -0400 |
|---|---|---|
| committer | Theodore Ts'o <tytso@mit.edu> | 2009-05-01 20:27:20 -0400 |
| commit | f40339031b04279c3fdde7ac5fe97db33b2a7694 (patch) | |
| tree | 62b565c12488c63e620e5686304c16ed3434b735 /fs/ext4/mballoc.c | |
| parent | bb23c20a851a5038b255a3c0d0aa56093c1da3f8 (diff) | |
| download | op-kernel-dev-f40339031b04279c3fdde7ac5fe97db33b2a7694.zip op-kernel-dev-f40339031b04279c3fdde7ac5fe97db33b2a7694.tar.gz | |
ext4: Make the length of the mb_history file tunable
In memory-constrained systems with many partitions, the ~68K for each
partition for the mb_history buffer can be excessive.
This patch adds a new mount option, mb_history_length, as well as a
way of setting the default via a module parameter (or via a sysfs
parameter in /sys/module/ext4/parameter/default_mb_history_length).
If the mb_history_length is set to zero, the mb_history facility is
disabled entirely.
Signed-off-by: Curt Wohlgemuth <curtw@google.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Diffstat (limited to 'fs/ext4/mballoc.c')
| -rw-r--r-- | fs/ext4/mballoc.c | 13 |
1 files changed, 7 insertions, 6 deletions
diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index dbd47ea..df75855 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -2413,7 +2413,8 @@ static void ext4_mb_history_release(struct super_block *sb) if (sbi->s_proc != NULL) { remove_proc_entry("mb_groups", sbi->s_proc); - remove_proc_entry("mb_history", sbi->s_proc); + if (sbi->s_mb_history_max) + remove_proc_entry("mb_history", sbi->s_proc); } kfree(sbi->s_mb_history); } @@ -2424,17 +2425,17 @@ static void ext4_mb_history_init(struct super_block *sb) int i; if (sbi->s_proc != NULL) { - proc_create_data("mb_history", S_IRUGO, sbi->s_proc, - &ext4_mb_seq_history_fops, sb); + if (sbi->s_mb_history_max) + proc_create_data("mb_history", S_IRUGO, sbi->s_proc, + &ext4_mb_seq_history_fops, sb); proc_create_data("mb_groups", S_IRUGO, sbi->s_proc, &ext4_mb_seq_groups_fops, sb); } - sbi->s_mb_history_max = 1000; sbi->s_mb_history_cur = 0; spin_lock_init(&sbi->s_mb_history_lock); i = sbi->s_mb_history_max * sizeof(struct ext4_mb_history); - sbi->s_mb_history = kzalloc(i, GFP_KERNEL); + sbi->s_mb_history = i ? kzalloc(i, GFP_KERNEL) : NULL; /* if we can't allocate history, then we simple won't use it */ } @@ -2444,7 +2445,7 @@ ext4_mb_store_history(struct ext4_allocation_context *ac) struct ext4_sb_info *sbi = EXT4_SB(ac->ac_sb); struct ext4_mb_history h; - if (unlikely(sbi->s_mb_history == NULL)) + if (sbi->s_mb_history == NULL) return; if (!(ac->ac_op & sbi->s_mb_history_filter)) |
