From 5dc7c10b87474c98116d3438739743cd77263e9f Mon Sep 17 00:00:00 2001 From: Dennis Zhou Date: Fri, 13 Dec 2019 16:22:21 -0800 Subject: btrfs: keep track of discardable_bytes for async discard Keep track of this metric so that we can understand how ahead or behind we are in discarding rate. This uses the same accounting method as discardable_extents, deltas between previous/current values and propagating them up. Signed-off-by: Dennis Zhou Reviewed-by: David Sterba [ update changelog ] Signed-off-by: David Sterba --- fs/btrfs/sysfs.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) (limited to 'fs/btrfs/sysfs.c') diff --git a/fs/btrfs/sysfs.c b/fs/btrfs/sysfs.c index 0ac122c67065..ce1da3fcd6c9 100644 --- a/fs/btrfs/sysfs.c +++ b/fs/btrfs/sysfs.c @@ -344,6 +344,17 @@ static const struct attribute_group btrfs_static_feature_attr_group = { */ #define discard_to_fs_info(_kobj) to_fs_info((_kobj)->parent->parent) +static ssize_t btrfs_discardable_bytes_show(struct kobject *kobj, + struct kobj_attribute *a, + char *buf) +{ + struct btrfs_fs_info *fs_info = discard_to_fs_info(kobj); + + return snprintf(buf, PAGE_SIZE, "%lld\n", + atomic64_read(&fs_info->discard_ctl.discardable_bytes)); +} +BTRFS_ATTR(discard, discardable_bytes, btrfs_discardable_bytes_show); + static ssize_t btrfs_discardable_extents_show(struct kobject *kobj, struct kobj_attribute *a, char *buf) @@ -356,6 +367,7 @@ static ssize_t btrfs_discardable_extents_show(struct kobject *kobj, BTRFS_ATTR(discard, discardable_extents, btrfs_discardable_extents_show); static const struct attribute *discard_debug_attrs[] = { + BTRFS_ATTR_PTR(discard, discardable_bytes), BTRFS_ATTR_PTR(discard, discardable_extents), NULL, }; -- cgit v1.2.3