Add mount option "priority_alloc=%s", now %s only supports "usage" and "off". The latter is used for remount. "priority_alloc=usage" will active priority aware allocator. This mount option changes the way of find_free_extent to search block groups and may cost more time.
Signed-off-by: Su Yue <suy.f...@cn.fujitsu.com> --- fs/btrfs/super.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c index cbc9d0d2c12d..4a6ccd4c29fd 100644 --- a/fs/btrfs/super.c +++ b/fs/btrfs/super.c @@ -326,6 +326,7 @@ enum { Opt_treelog, Opt_notreelog, Opt_usebackuproot, Opt_user_subvol_rm_allowed, + Opt_priority_allocator, /* Deprecated options */ Opt_alloc_start, @@ -393,6 +394,7 @@ static const match_table_t tokens = { {Opt_notreelog, "notreelog"}, {Opt_usebackuproot, "usebackuproot"}, {Opt_user_subvol_rm_allowed, "user_subvol_rm_allowed"}, + {Opt_priority_allocator, "priority_alloc=%s"}, /* Deprecated options */ {Opt_alloc_start, "alloc_start=%s"}, @@ -765,6 +767,18 @@ int btrfs_parse_options(struct btrfs_fs_info *info, char *options, case Opt_skip_balance: btrfs_set_opt(info->mount_opt, SKIP_BALANCE); break; + case Opt_priority_allocator: + if (strcmp(args[0].from, "usage") == 0) { + btrfs_set_and_info(info, PRIORITY_USAGE, + "using priority usage-aware allocator"); + } else if (strcmp(args[0].from, "off") == 0) { + btrfs_clear_and_info(info, PRIORITY_USAGE, + "priority awareallocator disabled"); + } else { + ret = -EINVAL; + goto out; + } + break; #ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY case Opt_check_integrity_including_extent_data: btrfs_info(info, @@ -1337,6 +1351,10 @@ static int btrfs_show_options(struct seq_file *seq, struct dentry *dentry) seq_puts(seq, ",inode_cache"); if (btrfs_test_opt(info, SKIP_BALANCE)) seq_puts(seq, ",skip_balance"); + if (btrfs_test_opt(info, PRIORITY_USAGE)) + seq_puts(seq, ",priority_alloc=usage"); + else + seq_puts(seq, ",priority_alloc=off"); #ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY if (btrfs_test_opt(info, CHECK_INTEGRITY_INCLUDING_EXTENT_DATA)) seq_puts(seq, ",check_int_data"); -- 2.19.1