f2fs: introduce sysfs atomic write statistics

introduce the below 4 new sysfs node for atomic write statistics.
- current_atomic_write: the total current atomic write block count,
                        which is not committed yet.
- peak_atomic_write: the peak value of total current atomic write block
                     count after boot.
- committed_atomic_block: the accumulated total committed atomic write
                          block count after boot.
- revoked_atomic_block: the accumulated total revoked atomic write block
                        count after boot.

Signed-off-by: Daeho Jeong <daehojeong@google.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

1 files changed, 46 insertions, 0 deletions

diff --git a/fs/f2fs/sysfs.c b/fs/f2fs/sysfs.c
index 6eeefe60a7af..eba5fb1629d7 100644
--- a/fs/f2fs/sysfs.c
+++ b/fs/f2fs/sysfs.c
@@ -339,6 +339,21 @@ static ssize_t f2fs_sbi_show(struct f2fs_attr *a,
 			sbi->gc_reclaimed_segs[sbi->gc_segment_mode]);
 	}
 
+	if (!strcmp(a->attr.name, "current_atomic_write")) {
+		s64 current_write = atomic64_read(&sbi->current_atomic_write);
+
+		return sysfs_emit(buf, "%lld\n", current_write);
+	}
+
+	if (!strcmp(a->attr.name, "peak_atomic_write"))
+		return sysfs_emit(buf, "%lld\n", sbi->peak_atomic_write);
+
+	if (!strcmp(a->attr.name, "committed_atomic_block"))
+		return sysfs_emit(buf, "%llu\n", sbi->committed_atomic_block);
+
+	if (!strcmp(a->attr.name, "revoked_atomic_block"))
+		return sysfs_emit(buf, "%llu\n", sbi->revoked_atomic_block);
+
 	ui = (unsigned int *)(ptr + a->offset);
 
 	return sprintf(buf, "%u\n", *ui);
@@ -608,6 +623,27 @@ out:
 		return count;
 	}
 
+	if (!strcmp(a->attr.name, "peak_atomic_write")) {
+		if (t != 0)
+			return -EINVAL;
+		sbi->peak_atomic_write = 0;
+		return count;
+	}
+
+	if (!strcmp(a->attr.name, "committed_atomic_block")) {
+		if (t != 0)
+			return -EINVAL;
+		sbi->committed_atomic_block = 0;
+		return count;
+	}
+
+	if (!strcmp(a->attr.name, "revoked_atomic_block")) {
+		if (t != 0)
+			return -EINVAL;
+		sbi->revoked_atomic_block = 0;
+		return count;
+	}
+
 	*ui = (unsigned int)t;
 
 	return count;
@@ -855,6 +891,12 @@ F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, gc_reclaimed_segments, gc_reclaimed_segs);
 F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, max_fragment_chunk, max_fragment_chunk);
 F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, max_fragment_hole, max_fragment_hole);
 
+/* For atomic write */
+F2FS_RO_ATTR(F2FS_SBI, f2fs_sb_info, current_atomic_write, current_atomic_write);
+F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, peak_atomic_write, peak_atomic_write);
+F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, committed_atomic_block, committed_atomic_block);
+F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, revoked_atomic_block, revoked_atomic_block);
+
 #define ATTR_LIST(name) (&f2fs_attr_##name.attr)
 static struct attribute *f2fs_attrs[] = {
 	ATTR_LIST(gc_urgent_sleep_time),
@@ -944,6 +986,10 @@ static struct attribute *f2fs_attrs[] = {
 	ATTR_LIST(gc_reclaimed_segments),
 	ATTR_LIST(max_fragment_chunk),
 	ATTR_LIST(max_fragment_hole),
+	ATTR_LIST(current_atomic_write),
+	ATTR_LIST(peak_atomic_write),
+	ATTR_LIST(committed_atomic_block),
+	ATTR_LIST(revoked_atomic_block),
 	NULL,
 };
 ATTRIBUTE_GROUPS(f2fs);