From 9555c6c180600b40f6e86bd4dc53bf47e06ed663 Mon Sep 17 00:00:00 2001 From: Ilya Dryomov Date: Mon, 16 Jan 2012 22:04:48 +0200 Subject: Btrfs: add skip_balance mount option Since restriper kthread starts involuntarily on mount and can suck cpu and memory bandwidth add a mount option to forcefully skip it. The restriper in that case hangs around in paused state and can be resumed from userspace when it's convenient. Signed-off-by: Ilya Dryomov --- fs/btrfs/ctree.h | 1 + fs/btrfs/super.c | 11 +++++++++-- fs/btrfs/volumes.c | 10 +++++++--- 3 files changed, 17 insertions(+), 5 deletions(-) (limited to 'fs') diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index 9997a59e4f58..99eb2bcd9aa7 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -1492,6 +1492,7 @@ struct btrfs_ioctl_defrag_range_args { #define BTRFS_MOUNT_AUTO_DEFRAG (1 << 16) #define BTRFS_MOUNT_INODE_MAP_CACHE (1 << 17) #define BTRFS_MOUNT_RECOVERY (1 << 18) +#define BTRFS_MOUNT_SKIP_BALANCE (1 << 19) #define btrfs_clear_opt(o, opt) ((o) &= ~BTRFS_MOUNT_##opt) #define btrfs_set_opt(o, opt) ((o) |= BTRFS_MOUNT_##opt) diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c index 34a8b6112ea4..063b521e3ded 100644 --- a/fs/btrfs/super.c +++ b/fs/btrfs/super.c @@ -164,8 +164,9 @@ enum { Opt_compress_type, Opt_compress_force, Opt_compress_force_type, Opt_notreelog, Opt_ratio, Opt_flushoncommit, Opt_discard, Opt_space_cache, Opt_clear_cache, Opt_user_subvol_rm_allowed, - Opt_enospc_debug, Opt_subvolrootid, Opt_defrag, - Opt_inode_cache, Opt_no_space_cache, Opt_recovery, Opt_err, + Opt_enospc_debug, Opt_subvolrootid, Opt_defrag, Opt_inode_cache, + Opt_no_space_cache, Opt_recovery, Opt_skip_balance, + Opt_err, }; static match_table_t tokens = { @@ -200,6 +201,7 @@ static match_table_t tokens = { {Opt_inode_cache, "inode_cache"}, {Opt_no_space_cache, "nospace_cache"}, {Opt_recovery, "recovery"}, + {Opt_skip_balance, "skip_balance"}, {Opt_err, NULL}, }; @@ -398,6 +400,9 @@ int btrfs_parse_options(struct btrfs_root *root, char *options) printk(KERN_INFO "btrfs: enabling auto recovery"); btrfs_set_opt(info->mount_opt, RECOVERY); break; + case Opt_skip_balance: + btrfs_set_opt(info->mount_opt, SKIP_BALANCE); + break; case Opt_err: printk(KERN_INFO "btrfs: unrecognized mount option " "'%s'\n", p); @@ -723,6 +728,8 @@ static int btrfs_show_options(struct seq_file *seq, struct vfsmount *vfs) seq_puts(seq, ",autodefrag"); if (btrfs_test_opt(root, INODE_MAP_CACHE)) seq_puts(seq, ",inode_cache"); + if (btrfs_test_opt(root, SKIP_BALANCE)) + seq_puts(seq, ",skip_balance"); return 0; } diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index 17e565388de0..e0160607e6e2 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -2707,15 +2707,19 @@ static int balance_kthread(void *data) struct btrfs_balance_control *bctl = (struct btrfs_balance_control *)data; struct btrfs_fs_info *fs_info = bctl->fs_info; - int ret; + int ret = 0; mutex_lock(&fs_info->volume_mutex); mutex_lock(&fs_info->balance_mutex); set_balance_control(bctl); - printk(KERN_INFO "btrfs: continuing balance\n"); - ret = btrfs_balance(bctl, NULL); + if (btrfs_test_opt(fs_info->tree_root, SKIP_BALANCE)) { + printk(KERN_INFO "btrfs: force skipping balance\n"); + } else { + printk(KERN_INFO "btrfs: continuing balance\n"); + ret = btrfs_balance(bctl, NULL); + } mutex_unlock(&fs_info->balance_mutex); mutex_unlock(&fs_info->volume_mutex); -- cgit v1.2.3