f2fs: introduce lifetime write IO statistics

This patch introduces lifetime IO write statistics exposed to the sysfs interface.
The write IO amount is obtained from block layer, accumulated in the file system and
stored in the hot node summary of checkpoint.

Signed-off-by: Shuoran Liu <liushuoran@huawei.com>
Signed-off-by: Pengyang Hou <houpengyang@huawei.com>
[Jaegeuk Kim: add sysfs documentation]
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

diff --git a/Documentation/ABI/testing/sysfs-fs-f2fs b/Documentation/ABI/testing/sysfs-fs-f2fs
index 523cb9d4e27236eb2c4e2c18309992e6893e5a8e..a809f6005f1464ed7c86133db7b4b95d4a3c7388 100644 (file)
--- a/Documentation/ABI/testing/sysfs-fs-f2fs
+++ b/Documentation/ABI/testing/sysfs-fs-f2fs
@@ -106,3 +106,9 @@ Description:
                 Controls dirty nat entries ratio threshold, if current
                 ratio exceeds configured threshold, checkpoint will
                 be triggered for flushing dirty nat entries.
+
+What:          /sys/fs/f2fs/<disk>/lifetime_write_kbytes
+Date:          January 2016
+Contact:       "Shuoran Liu" <liushuoran@huawei.com>
+Description:
+                Shows total written kbytes issued to disk.

diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c
index 4b6f9c08f6fa2230d1671e27219c3a78f0f7291b..112e19fdbe08647124c84e20fa0e3d67cbb6ba1d 100644 (file)
--- a/fs/f2fs/checkpoint.c
+++ b/fs/f2fs/checkpoint.c
@@ -921,6 +921,9 @@ static int do_checkpoint(struct f2fs_sb_info *sbi, struct cp_control *cpc)
        int cp_payload_blks = __cp_payload(sbi);
        block_t discard_blk = NEXT_FREE_BLKADDR(sbi, curseg);
        bool invalidate = false;
+       struct super_block *sb = sbi->sb;
+       struct curseg_info *seg_i = CURSEG_I(sbi, CURSEG_HOT_NODE);
+       u64 kbytes_written;
 
        /*
         * This avoids to conduct wrong roll-forward operations and uses
@@ -1034,6 +1037,14 @@ static int do_checkpoint(struct f2fs_sb_info *sbi, struct cp_control *cpc)
 
        write_data_summaries(sbi, start_blk);
        start_blk += data_sum_blocks;
+
+       /* Record write statistics in the hot node summary */
+       kbytes_written = sbi->kbytes_written;
+       if (sb->s_bdev->bd_part)
+               kbytes_written += BD_PART_WRITTEN(sbi);
+
+       seg_i->sum_blk->info.kbytes_written = cpu_to_le64(kbytes_written);
+
        if (__remain_node_summaries(cpc->reason)) {
                write_node_summaries(sbi, start_blk);
                start_blk += NR_CURSEG_NODE_TYPE;

diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 4e7eab9f3f5afdf61cad38c7724b8a500268b17f..5b6fd541551cd2a017891d425566e65750353526 100644 (file)
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -846,8 +846,19 @@ struct f2fs_sb_info {
        struct list_head s_list;
        struct mutex umount_mutex;
        unsigned int shrinker_run_no;
+
+       /* For write statistics */
+       u64 sectors_written_start;
+       u64 kbytes_written;
 };
 
+/* For write statistics. Suppose sector size is 512 bytes,
+ * and the return value is in kbytes. s is of struct f2fs_sb_info.
+ */
+#define BD_PART_WRITTEN(s)                                              \
+(((u64)part_stat_read(s->sb->s_bdev->bd_part, sectors[1]) -             \
+               s->sectors_written_start) >> 1)
+
 static inline void f2fs_update_time(struct f2fs_sb_info *sbi, int type)
 {
        sbi->last_time[type] = jiffies;

diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
index 0ea5bcccab6d0306608d5861e7a0edccfc55a0ff..58d9a5574bb0d85ddf59c9061b5c7044dbcbcd70 100644 (file)
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -126,6 +126,19 @@ static unsigned char *__struct_ptr(struct f2fs_sb_info *sbi, int struct_type)
        return NULL;
 }
 
+static ssize_t lifetime_write_kbytes_show(struct f2fs_attr *a,
+               struct f2fs_sb_info *sbi, char *buf)
+{
+       struct super_block *sb = sbi->sb;
+
+       if (!sb->s_bdev->bd_part)
+               return snprintf(buf, PAGE_SIZE, "0\n");
+
+       return snprintf(buf, PAGE_SIZE, "%llu\n",
+               (unsigned long long)(sbi->kbytes_written +
+                       BD_PART_WRITTEN(sbi)));
+}
+
 static ssize_t f2fs_sbi_show(struct f2fs_attr *a,
                        struct f2fs_sb_info *sbi, char *buf)
 {
@@ -204,6 +217,9 @@ static struct f2fs_attr f2fs_attr_##_name = {                       \
                f2fs_sbi_show, f2fs_sbi_store,                  \
                offsetof(struct struct_name, elname))
 
+#define F2FS_GENERAL_RO_ATTR(name) \
+static struct f2fs_attr f2fs_attr_##name = __ATTR(name, 0444, name##_show, NULL)
+
 F2FS_RW_ATTR(GC_THREAD, f2fs_gc_kthread, gc_min_sleep_time, min_sleep_time);
 F2FS_RW_ATTR(GC_THREAD, f2fs_gc_kthread, gc_max_sleep_time, max_sleep_time);
 F2FS_RW_ATTR(GC_THREAD, f2fs_gc_kthread, gc_no_gc_sleep_time, no_gc_sleep_time);
@@ -221,6 +237,7 @@ F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, max_victim_search, max_victim_search);
 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_GENERAL_RO_ATTR(lifetime_write_kbytes);
 
 #define ATTR_LIST(name) (&f2fs_attr_##name.attr)
 static struct attribute *f2fs_attrs[] = {
@@ -241,6 +258,7 @@ static struct attribute *f2fs_attrs[] = {
        ATTR_LIST(dirty_nats_ratio),
        ATTR_LIST(cp_interval),
        ATTR_LIST(idle_interval),
+       ATTR_LIST(lifetime_write_kbytes),
        NULL,
 };
 
@@ -768,8 +786,6 @@ static int f2fs_remount(struct super_block *sb, int *flags, char *data)
        bool need_stop_gc = false;
        bool no_extent_cache = !test_opt(sbi, EXTENT_CACHE);
 
-       sync_filesystem(sb);
-
        /*
         * Save the old mount options in case we
         * need to restore them.
@@ -777,6 +793,13 @@ static int f2fs_remount(struct super_block *sb, int *flags, char *data)
        org_mount_opt = sbi->mount_opt;
        active_logs = sbi->active_logs;
 
+       if (*flags & MS_RDONLY) {
+               set_opt(sbi, FASTBOOT);
+               set_sbi_flag(sbi, SBI_IS_DIRTY);
+       }
+
+       sync_filesystem(sb);
+
        sbi->mount_opt.opt = 0;
        default_options(sbi);
 
@@ -1244,6 +1267,7 @@ static int f2fs_fill_super(struct super_block *sb, void *data, int silent)
        bool retry = true, need_fsck = false;
        char *options = NULL;
        int recovery, i, valid_super_block;
+       struct curseg_info *seg_i;
 
 try_onemore:
        err = -EINVAL;
@@ -1374,6 +1398,17 @@ try_onemore:
                goto free_nm;
        }
 
+       /* For write statistics */
+       if (sb->s_bdev->bd_part)
+               sbi->sectors_written_start =
+                       (u64)part_stat_read(sb->s_bdev->bd_part, sectors[1]);
+
+       /* Read accumulated write IO statistics if exists */
+       seg_i = CURSEG_I(sbi, CURSEG_HOT_NODE);
+       if (__exist_node_summaries(sbi))
+               sbi->kbytes_written =
+                       le64_to_cpu(seg_i->sum_blk->info.kbytes_written);
+
        build_gc_manager(sbi);
 
        /* get an inode for node space */

diff --git a/include/linux/f2fs_fs.h b/include/linux/f2fs_fs.h
index e59c3be921069635c90da255087b12978bf70c9a..67aa01df777d95cb4c9cb7d574ada3e97cb5fb37 100644 (file)
--- a/include/linux/f2fs_fs.h
+++ b/include/linux/f2fs_fs.h
@@ -358,6 +358,12 @@ struct summary_footer {
                                sizeof(struct sit_journal_entry))
 #define SIT_JOURNAL_RESERVED   ((SUM_JOURNAL_SIZE - 2) %\
                                sizeof(struct sit_journal_entry))
+
+/* Reserved area should make size of f2fs_extra_info equals to
+ * that of nat_journal and sit_journal.
+ */
+#define EXTRA_INFO_RESERVED    (SUM_JOURNAL_SIZE - 2 - 8)
+
 /*
  * frequently updated NAT/SIT entries can be stored in the spare area in
  * summary blocks
@@ -387,6 +393,11 @@ struct sit_journal {
        __u8 reserved[SIT_JOURNAL_RESERVED];
 } __packed;
 
+struct f2fs_extra_info {
+       __le64 kbytes_written;
+       __u8 reserved[EXTRA_INFO_RESERVED];
+} __packed;
+
 /* 4KB-sized summary block structure */
 struct f2fs_summary_block {
        struct f2fs_summary entries[ENTRIES_IN_SUM];
@@ -394,10 +405,11 @@ struct f2fs_summary_block {
                __le16 n_nats;
                __le16 n_sits;
        };
-       /* spare area is used by NAT or SIT journals */
+       /* spare area is used by NAT or SIT journals or extra info */
        union {
                struct nat_journal nat_j;
                struct sit_journal sit_j;
+               struct f2fs_extra_info info;
        };
        struct summary_footer footer;
 } __packed;