[PATCH v4] f2fs: add new idle interval timing for discard and gc paths

From: Sahitya Tummala
Date: Wed Sep 19 2018 - 04:49:12 EST


This helps to control the frequency of submission of discard and
GC requests independently, based on the need.

Suggested-by: Chao Yu <yuchao0@xxxxxxxxxx>
Signed-off-by: Sahitya Tummala <stummala@xxxxxxxxxxxxxx>
---
v4:
- initialize and use sbi->last_time[discard_time], sbi->last_time[gc_time]

Documentation/ABI/testing/sysfs-fs-f2fs | 17 ++++++++++++++++-
fs/f2fs/f2fs.h | 30 +++++++++++++++++++++++++++---
fs/f2fs/gc.c | 2 +-
fs/f2fs/segment.c | 14 +++++---------
fs/f2fs/super.c | 2 ++
fs/f2fs/sysfs.c | 5 +++++
6 files changed, 56 insertions(+), 14 deletions(-)

diff --git a/Documentation/ABI/testing/sysfs-fs-f2fs b/Documentation/ABI/testing/sysfs-fs-f2fs
index 94a24ae..3ac4177 100644
--- a/Documentation/ABI/testing/sysfs-fs-f2fs
+++ b/Documentation/ABI/testing/sysfs-fs-f2fs
@@ -121,7 +121,22 @@ What: /sys/fs/f2fs/<disk>/idle_interval
Date: January 2016
Contact: "Jaegeuk Kim" <jaegeuk@xxxxxxxxxx>
Description:
- Controls the idle timing.
+ Controls the idle timing for all paths other than
+ discard and gc path.
+
+What: /sys/fs/f2fs/<disk>/discard_idle_interval
+Date: September 2018
+Contact: "Chao Yu" <yuchao0@xxxxxxxxxx>
+Contact: "Sahitya Tummala" <stummala@xxxxxxxxxxxxxx>
+Description:
+ Controls the idle timing for discard path.
+
+What: /sys/fs/f2fs/<disk>/gc_idle_interval
+Date: September 2018
+Contact: "Chao Yu" <yuchao0@xxxxxxxxxx>
+Contact: "Sahitya Tummala" <stummala@xxxxxxxxxxxxxx>
+Description:
+ Controls the idle timing for gc path.

What: /sys/fs/f2fs/<disk>/iostat_enable
Date: August 2017
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 88b8d50..c47b7d2 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -1095,6 +1095,8 @@ enum {
enum {
CP_TIME,
REQ_TIME,
+ DISCARD_TIME,
+ GC_TIME,
MAX_TIME,
};

@@ -1346,7 +1348,15 @@ static inline bool time_to_inject(struct f2fs_sb_info *sbi, int type)

static inline void f2fs_update_time(struct f2fs_sb_info *sbi, int type)
{
- sbi->last_time[type] = jiffies;
+ unsigned long now = jiffies;
+
+ sbi->last_time[type] = now;
+
+ /* DISCARD_TIME and GC_TIME are based on REQ_TIME */
+ if (type == REQ_TIME) {
+ sbi->last_time[DISCARD_TIME] = now;
+ sbi->last_time[GC_TIME] = now;
+ }
}

static inline bool f2fs_time_over(struct f2fs_sb_info *sbi, int type)
@@ -1356,7 +1366,21 @@ static inline bool f2fs_time_over(struct f2fs_sb_info *sbi, int type)
return time_after(jiffies, sbi->last_time[type] + interval);
}

-static inline bool is_idle(struct f2fs_sb_info *sbi)
+static inline unsigned int f2fs_time_to_wait(struct f2fs_sb_info *sbi,
+ int type)
+{
+ unsigned long interval = sbi->interval_time[type] * HZ;
+ unsigned int wait_ms = 0;
+ long delta;
+
+ delta = (sbi->last_time[type] + interval) - jiffies;
+ if (delta > 0)
+ wait_ms = jiffies_to_msecs(delta);
+
+ return wait_ms;
+}
+
+static inline bool is_idle(struct f2fs_sb_info *sbi, int type)
{
struct block_device *bdev = sbi->sb->s_bdev;
struct request_queue *q = bdev_get_queue(bdev);
@@ -1365,7 +1389,7 @@ static inline bool is_idle(struct f2fs_sb_info *sbi)
if (rl->count[BLK_RW_SYNC] || rl->count[BLK_RW_ASYNC])
return false;

- return f2fs_time_over(sbi, REQ_TIME);
+ return f2fs_time_over(sbi, type);
}

/*
diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c
index 5c8d004..49e2328 100644
--- a/fs/f2fs/gc.c
+++ b/fs/f2fs/gc.c
@@ -83,7 +83,7 @@ static int gc_thread_func(void *data)
if (!mutex_trylock(&sbi->gc_mutex))
goto next;

- if (!is_idle(sbi)) {
+ if (!is_idle(sbi, GC_TIME)) {
increase_sleep_time(gc_th, &wait_ms);
mutex_unlock(&sbi->gc_mutex);
goto next;
diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
index 187c848..67cf7e4 100644
--- a/fs/f2fs/segment.c
+++ b/fs/f2fs/segment.c
@@ -511,7 +511,7 @@ void f2fs_balance_fs_bg(struct f2fs_sb_info *sbi)
else
f2fs_build_free_nids(sbi, false, false);

- if (!is_idle(sbi) &&
+ if (!is_idle(sbi, REQ_TIME) &&
(!excess_dirty_nats(sbi) && !excess_dirty_nodes(sbi)))
return;

@@ -1311,7 +1311,7 @@ static unsigned int __issue_discard_cmd_orderly(struct f2fs_sb_info *sbi,
if (dc->state != D_PREP)
goto next;

- if (dpolicy->io_aware && !is_idle(sbi)) {
+ if (dpolicy->io_aware && !is_idle(sbi, DISCARD_TIME)) {
io_interrupted = true;
break;
}
@@ -1371,7 +1371,7 @@ static int __issue_discard_cmd(struct f2fs_sb_info *sbi,
f2fs_bug_on(sbi, dc->state != D_PREP);

if (dpolicy->io_aware && i < dpolicy->io_aware_gran &&
- !is_idle(sbi)) {
+ !is_idle(sbi, DISCARD_TIME)) {
io_interrupted = true;
break;
}
@@ -1564,8 +1564,6 @@ static int issue_discard_thread(void *data)
struct discard_policy dpolicy;
unsigned int wait_ms = DEF_MIN_DISCARD_ISSUE_TIME;
int issued;
- unsigned long interval = sbi->interval_time[REQ_TIME] * HZ;
- long delta;

set_freezable();

@@ -1602,10 +1600,8 @@ static int issue_discard_thread(void *data)
__wait_all_discard_cmd(sbi, &dpolicy);
wait_ms = dpolicy.min_interval;
} else if (issued == -1){
- delta = (sbi->last_time[REQ_TIME] + interval) - jiffies;
- if (delta > 0)
- wait_ms = jiffies_to_msecs(delta);
- else
+ wait_ms = f2fs_time_to_wait(sbi, DISCARD_TIME);
+ if (!wait_ms)
wait_ms = dpolicy.mid_interval;
} else {
wait_ms = dpolicy.max_interval;
diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
index 3106da1..2f67948 100644
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -2463,6 +2463,8 @@ static void init_sb_info(struct f2fs_sb_info *sbi)
sbi->dir_level = DEF_DIR_LEVEL;
sbi->interval_time[CP_TIME] = DEF_CP_INTERVAL;
sbi->interval_time[REQ_TIME] = DEF_IDLE_INTERVAL;
+ sbi->interval_time[DISCARD_TIME] = DEF_IDLE_INTERVAL;
+ sbi->interval_time[GC_TIME] = DEF_IDLE_INTERVAL;
clear_sbi_flag(sbi, SBI_NEED_FSCK);

for (i = 0; i < NR_COUNT_TYPE; i++)
diff --git a/fs/f2fs/sysfs.c b/fs/f2fs/sysfs.c
index 81c0e53..0afe99c 100644
--- a/fs/f2fs/sysfs.c
+++ b/fs/f2fs/sysfs.c
@@ -407,6 +407,9 @@ static ssize_t f2fs_feature_show(struct f2fs_attr *a,
F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, dir_level, dir_level);
F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, cp_interval, interval_time[CP_TIME]);
F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, idle_interval, interval_time[REQ_TIME]);
+F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, discard_idle_interval,
+ interval_time[DISCARD_TIME]);
+F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, gc_idle_interval, interval_time[GC_TIME]);
F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, iostat_enable, iostat_enable);
F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, readdir_ra, readdir_ra);
F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, gc_pin_file_thresh, gc_pin_file_threshold);
@@ -460,6 +463,8 @@ static ssize_t f2fs_feature_show(struct f2fs_attr *a,
ATTR_LIST(dirty_nats_ratio),
ATTR_LIST(cp_interval),
ATTR_LIST(idle_interval),
+ ATTR_LIST(discard_idle_interval),
+ ATTR_LIST(gc_idle_interval),
ATTR_LIST(iostat_enable),
ATTR_LIST(readdir_ra),
ATTR_LIST(gc_pin_file_thresh),
--
Qualcomm India Private Limited, on behalf of Qualcomm Innovation Center, Inc.
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project.