btrfs: zoned: allow disabling of zone auto reclaim
Automatically reclaiming dirty zones might not always be desired for all
workloads, especially as there are currently still some rough edges with
the relocation code on zoned filesystems.
Allow disabling zone auto reclaim on a per filesystem basis by writing 0
as the threshold value.
Reviewed-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
diff --git a/fs/btrfs/sysfs.c b/fs/btrfs/sysfs.c
index bfe5e27..c126130 100644
--- a/fs/btrfs/sysfs.c
+++ b/fs/btrfs/sysfs.c
@@ -984,7 +984,8 @@ static ssize_t btrfs_bg_reclaim_threshold_show(struct kobject *kobj,
struct btrfs_fs_info *fs_info = to_fs_info(kobj);
ssize_t ret;
- ret = scnprintf(buf, PAGE_SIZE, "%d\n", fs_info->bg_reclaim_threshold);
+ ret = scnprintf(buf, PAGE_SIZE, "%d\n",
+ READ_ONCE(fs_info->bg_reclaim_threshold));
return ret;
}
@@ -1001,10 +1002,10 @@ static ssize_t btrfs_bg_reclaim_threshold_store(struct kobject *kobj,
if (ret)
return ret;
- if (thresh <= 50 || thresh > 100)
+ if (thresh != 0 && (thresh <= 50 || thresh > 100))
return -EINVAL;
- fs_info->bg_reclaim_threshold = thresh;
+ WRITE_ONCE(fs_info->bg_reclaim_threshold, thresh);
return len;
}