[PATCH 2/2] f2fs: introduce gc_mode sysfs node

From: Yangtao Li
Date: Mon Oct 24 2022 - 23:32:45 EST


gc_mode sysfs node can show the current gc_mode as a string.
Introducing it increases readability.

Signed-off-by: Yangtao Li <frank.li@xxxxxxxx>
---
Documentation/ABI/testing/sysfs-fs-f2fs | 6 ++++++
fs/f2fs/f2fs.h | 1 +
fs/f2fs/sysfs.c | 18 ++++++++++++++++++
3 files changed, 25 insertions(+)

diff --git a/Documentation/ABI/testing/sysfs-fs-f2fs b/Documentation/ABI/testing/sysfs-fs-f2fs
index 483639fb727b..6466f3b1f0a9 100644
--- a/Documentation/ABI/testing/sysfs-fs-f2fs
+++ b/Documentation/ABI/testing/sysfs-fs-f2fs
@@ -634,3 +634,9 @@ Date: July 2022
Contact: "Daeho Jeong" <daehojeong@xxxxxxxxxx>
Description: Show the accumulated total revoked atomic write block count after boot.
If you write "0" here, you can initialize to "0".
+
+What: /sys/fs/f2fs/<disk>/gc_mode
+Date: October 2022
+Contact: "Yangtao Li" <frank.li@xxxxxxxx>
+Description: Show the current gc_mode as a string.
+ This is a read-only entry.
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index e6355a5683b7..80f23e44a442 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -1318,6 +1318,7 @@ enum {
MAX_TIME,
};

+/* Note that you need to keep synchronization with this gc_mode_names array */
enum {
GC_NORMAL,
GC_IDLE_CB,
diff --git a/fs/f2fs/sysfs.c b/fs/f2fs/sysfs.c
index 49898a7243ba..058857d8b3b9 100644
--- a/fs/f2fs/sysfs.c
+++ b/fs/f2fs/sysfs.c
@@ -41,6 +41,16 @@ enum {
ATGC_INFO, /* struct atgc_management */
};

+static const char *gc_mode_names[MAX_GC_MODE] = {
+ "GC_NORMAL",
+ "GC_IDLE_CB",
+ "GC_IDLE_GREEDY",
+ "GC_IDLE_AT",
+ "GC_URGENT_HIGH",
+ "GC_URGENT_LOW",
+ "GC_URGENT_MID"
+};
+
struct f2fs_attr {
struct attribute attr;
ssize_t (*show)(struct f2fs_attr *, struct f2fs_sb_info *, char *);
@@ -133,6 +143,12 @@ static ssize_t pending_discard_show(struct f2fs_attr *a,
&SM_I(sbi)->dcc_info->discard_cmd_cnt));
}

+static ssize_t gc_mode_show(struct f2fs_attr *a,
+ struct f2fs_sb_info *sbi, char *buf)
+{
+ return sprintf(buf, "%s\n", gc_mode_names[sbi->gc_mode]);
+}
+
static ssize_t features_show(struct f2fs_attr *a,
struct f2fs_sb_info *sbi, char *buf)
{
@@ -823,6 +839,7 @@ F2FS_GENERAL_RO_ATTR(encoding);
F2FS_GENERAL_RO_ATTR(mounted_time_sec);
F2FS_GENERAL_RO_ATTR(main_blkaddr);
F2FS_GENERAL_RO_ATTR(pending_discard);
+F2FS_GENERAL_RO_ATTR(gc_mode);
#ifdef CONFIG_F2FS_STAT_FS
F2FS_STAT_ATTR(STAT_INFO, f2fs_stat_info, cp_foreground_calls, cp_count);
F2FS_STAT_ATTR(STAT_INFO, f2fs_stat_info, cp_background_calls, bg_cp_count);
@@ -904,6 +921,7 @@ static struct attribute *f2fs_attrs[] = {
ATTR_LIST(max_discard_issue_time),
ATTR_LIST(discard_granularity),
ATTR_LIST(pending_discard),
+ ATTR_LIST(gc_mode),
ATTR_LIST(batched_trim_sections),
ATTR_LIST(ipu_policy),
ATTR_LIST(min_ipu_util),
--
2.25.1