Keep track of how much we are discarding and how often we are reusing
with async discard.
Signed-off-by: Dennis Zhou <dennis@xxxxxxxxxx>
---
fs/btrfs/ctree.h | 3 +++
fs/btrfs/discard.c | 5 +++++
fs/btrfs/free-space-cache.c | 10 ++++++++++
fs/btrfs/sysfs.c | 36 ++++++++++++++++++++++++++++++++++++
4 files changed, 54 insertions(+)
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index b5608f8dc41a..2f52b29ff74c 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -453,6 +453,9 @@ struct btrfs_discard_ctl {
atomic_t delay;
atomic_t iops_limit;
atomic64_t bps_limit;
+ atomic64_t discard_extent_bytes;
+ atomic64_t discard_bitmap_bytes;
+ atomic64_t discard_bytes_saved;
};
/* delayed seq elem */
diff --git a/fs/btrfs/discard.c b/fs/btrfs/discard.c
index d99ba31e6f3b..f0088ca19d28 100644
--- a/fs/btrfs/discard.c
+++ b/fs/btrfs/discard.c
@@ -280,10 +280,12 @@ static void btrfs_discard_workfn(struct work_struct *work)
cache->discard_cursor,
btrfs_block_group_end(cache),
minlen, maxlen, true);
+ atomic64_add(trimmed, &discard_ctl->discard_bitmap_bytes);
} else {
btrfs_trim_block_group(cache, &trimmed, cache->discard_cursor,
btrfs_block_group_end(cache),
minlen, true);
+ atomic64_add(trimmed, &discard_ctl->discard_extent_bytes);
}
discard_ctl->prev_discard = trimmed;
@@ -408,6 +410,9 @@ void btrfs_discard_init(struct btrfs_fs_info *fs_info)
atomic_set(&discard_ctl->delay, BTRFS_DISCARD_MAX_DELAY);
atomic_set(&discard_ctl->iops_limit, BTRFS_DISCARD_MAX_IOPS);
atomic64_set(&discard_ctl->bps_limit, 0);
+ atomic64_set(&discard_ctl->discard_extent_bytes, 0);
+ atomic64_set(&discard_ctl->discard_bitmap_bytes, 0);
+ atomic64_set(&discard_ctl->discard_bytes_saved, 0);
}
void btrfs_discard_cleanup(struct btrfs_fs_info *fs_info)
diff --git a/fs/btrfs/free-space-cache.c b/fs/btrfs/free-space-cache.c
index ed35dc090df6..480119016c0d 100644
--- a/fs/btrfs/free-space-cache.c
+++ b/fs/btrfs/free-space-cache.c
@@ -2773,6 +2773,8 @@ u64 btrfs_find_space_for_alloc(struct btrfs_block_group_cache *block_group,
u64 *max_extent_size)
{
struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl;
+ struct btrfs_discard_ctl *discard_ctl =
+ &block_group->fs_info->discard_ctl;
struct btrfs_free_space *entry = NULL;
u64 bytes_search = bytes + empty_size;
u64 ret = 0;
@@ -2797,6 +2799,9 @@ u64 btrfs_find_space_for_alloc(struct btrfs_block_group_cache *block_group,
align_gap = entry->offset;
align_gap_flags = entry->flags;
+ if (!btrfs_free_space_trimmed(entry))
+ atomic64_add(bytes, &discard_ctl->discard_bytes_saved);
+
entry->offset = offset + bytes;
WARN_ON(entry->bytes < bytes + align_gap_len);
@@ -2901,6 +2906,8 @@ u64 btrfs_alloc_from_cluster(struct btrfs_block_group_cache *block_group,
u64 min_start, u64 *max_extent_size)
{
struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl;
+ struct btrfs_discard_ctl *discard_ctl =
+ &block_group->fs_info->discard_ctl;
struct btrfs_free_space *entry = NULL;
struct rb_node *node;
u64 ret = 0;
@@ -2965,6 +2972,9 @@ u64 btrfs_alloc_from_cluster(struct btrfs_block_group_cache *block_group,
spin_lock(&ctl->tree_lock);
+ if (!btrfs_free_space_trimmed(entry))
+ atomic64_add(bytes, &discard_ctl->discard_bytes_saved);
+
ctl->free_space -= bytes;
if (!entry->bitmap && !btrfs_free_space_trimmed(entry))
ctl->discardable_bytes[0] -= bytes;
diff --git a/fs/btrfs/sysfs.c b/fs/btrfs/sysfs.c
index 6fc4d644401b..29a290d75492 100644
--- a/fs/btrfs/sysfs.c
+++ b/fs/btrfs/sysfs.c
@@ -551,11 +551,47 @@ static ssize_t btrfs_discard_bps_limit_store(struct kobject *kobj,
BTRFS_ATTR_RW(discard, bps_limit, btrfs_discard_bps_limit_show,
btrfs_discard_bps_limit_store);
+static ssize_t btrfs_discard_extent_bytes_show(struct kobject *kobj,
+ struct kobj_attribute *a,
+ char *buf)
+{
+ struct btrfs_fs_info *fs_info = to_fs_info(kobj->parent);
+
+ return snprintf(buf, PAGE_SIZE, "%lld\n",
+ atomic64_read(&fs_info->discard_ctl.discard_extent_bytes));
+}
+BTRFS_ATTR(discard, discard_extent_bytes, btrfs_discard_extent_bytes_show);
+
+static ssize_t btrfs_discard_bitmap_bytes_show(struct kobject *kobj,
+ struct kobj_attribute *a,
+ char *buf)
+{
+ struct btrfs_fs_info *fs_info = to_fs_info(kobj->parent);
+
+ return snprintf(buf, PAGE_SIZE, "%lld\n",
+ atomic64_read(&fs_info->discard_ctl.discard_bitmap_bytes));
+}
+BTRFS_ATTR(discard, discard_bitmap_bytes, btrfs_discard_bitmap_bytes_show);
+
+static ssize_t btrfs_discard_bytes_saved_show(struct kobject *kobj,
+ struct kobj_attribute *a,
+ char *buf)
+{
+ struct btrfs_fs_info *fs_info = to_fs_info(kobj->parent);
+
+ return snprintf(buf, PAGE_SIZE, "%lld\n",
+ atomic64_read(&fs_info->discard_ctl.discard_bytes_saved));
+}
+BTRFS_ATTR(discard, discard_bytes_saved, btrfs_discard_bytes_saved_show);
+
static const struct attribute *discard_attrs[] = {
BTRFS_ATTR_PTR(discard, discard_extents),
BTRFS_ATTR_PTR(discard, discardable_bytes),
BTRFS_ATTR_PTR(discard, iops_limit),
BTRFS_ATTR_PTR(discard, bps_limit),
+ BTRFS_ATTR_PTR(discard, discard_extent_bytes),
+ BTRFS_ATTR_PTR(discard, discard_bitmap_bytes),
+ BTRFS_ATTR_PTR(discard, discard_bytes_saved),
NULL,
};
--
2.17.1
