f2fs: add sysfs nodes to get GC info for each GC mode

Added gc_reclaimed_segments and gc_segment_mode sysfs nodes.
1) "gc_reclaimed_segments" shows how many segments have been
reclaimed by GC during a specific GC mode.
2) "gc_segment_mode" is used to control for which gc mode
the "gc_reclaimed_segments" node shows.

Signed-off-by: Daeho Jeong <daehojeong@google.com>
Reviewed-by: Chao Yu <chao@kernel.org>
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 ef4b921..845c4be 100644 (file)
--- a/Documentation/ABI/testing/sysfs-fs-f2fs
+++ b/Documentation/ABI/testing/sysfs-fs-f2fs
@@ -493,3 +493,17 @@ Contact:   "Chao Yu" <yuchao0@huawei.com>
 Description:   When ATGC is on, it controls age threshold to bypass GCing young
                candidates whose age is not beyond the threshold, by default it was
                initialized as 604800 seconds (equals to 7 days).
+
+What:          /sys/fs/f2fs/<disk>/gc_reclaimed_segments
+Date:          July 2021
+Contact:       "Daeho Jeong" <daehojeong@google.com>
+Description:   Show how many segments have been reclaimed by GC during a specific
+               GC mode (0: GC normal, 1: GC idle CB, 2: GC idle greedy,
+               3: GC idle AT, 4: GC urgent high, 5: GC urgent low)
+               You can re-initialize this value to "0".
+
+What:          /sys/fs/f2fs/<disk>/gc_segment_mode
+Date:          July 2021
+Contact:       "Daeho Jeong" <daehojeong@google.com>
+Description:   You can control for which gc mode the "gc_reclaimed_segments" node shows.
+               Refer to the description of the modes in "gc_reclaimed_segments".

diff --git a/fs/f2fs/debug.c b/fs/f2fs/debug.c
index 8333250..53ed1e9 100644 (file)
--- a/fs/f2fs/debug.c
+++ b/fs/f2fs/debug.c
@@ -450,6 +450,15 @@ static int stat_show(struct seq_file *s, void *v)
                                si->data_segs, si->bg_data_segs);
                seq_printf(s, "  - node segments : %d (%d)\n",
                                si->node_segs, si->bg_node_segs);
+               seq_printf(s, "  - Reclaimed segs : Normal (%d), Idle CB (%d), "
+                               "Idle Greedy (%d), Idle AT (%d), "
+                               "Urgent High (%d), Urgent Low (%d)\n",
+                               si->sbi->gc_reclaimed_segs[GC_NORMAL],
+                               si->sbi->gc_reclaimed_segs[GC_IDLE_CB],
+                               si->sbi->gc_reclaimed_segs[GC_IDLE_GREEDY],
+                               si->sbi->gc_reclaimed_segs[GC_IDLE_AT],
+                               si->sbi->gc_reclaimed_segs[GC_URGENT_HIGH],
+                               si->sbi->gc_reclaimed_segs[GC_URGENT_LOW]);
                seq_printf(s, "Try to move %d blocks (BG: %d)\n", si->tot_blks,
                                si->bg_data_blks + si->bg_node_blks);
                seq_printf(s, "  - data blocks : %d (%d)\n", si->data_blks,

diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index ee8eb33..49d35e2 100644 (file)
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -1253,6 +1253,7 @@ enum {
        GC_IDLE_AT,
        GC_URGENT_HIGH,
        GC_URGENT_LOW,
+       MAX_GC_MODE,
 };
 
 enum {
@@ -1733,6 +1734,10 @@ struct f2fs_sb_info {
        struct kmem_cache *inline_xattr_slab;   /* inline xattr entry */
        unsigned int inline_xattr_slab_size;    /* default inline xattr slab size */
 
+       /* For reclaimed segs statistics per each GC mode */
+       unsigned int gc_segment_mode;           /* GC state for reclaimed segments */
+       unsigned int gc_reclaimed_segs[MAX_GC_MODE];    /* Reclaimed segs for each mode */
+
 #ifdef CONFIG_F2FS_FS_COMPRESSION
        struct kmem_cache *page_array_slab;     /* page array entry */
        unsigned int page_array_slab_size;      /* default page array slab size */

diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c
index 0e42ee5..d951182 100644 (file)
--- a/fs/f2fs/gc.c
+++ b/fs/f2fs/gc.c
@@ -1646,6 +1646,7 @@ static int do_garbage_collect(struct f2fs_sb_info *sbi,
                                                        force_migrate);
 
                stat_inc_seg_count(sbi, type, gc_type);
+               sbi->gc_reclaimed_segs[sbi->gc_mode]++;
                migrated++;
 
 freed:

diff --git a/fs/f2fs/sysfs.c b/fs/f2fs/sysfs.c
index 6642246..15fe30d 100644 (file)
--- a/fs/f2fs/sysfs.c
+++ b/fs/f2fs/sysfs.c
@@ -307,6 +307,14 @@ static ssize_t f2fs_sbi_show(struct f2fs_attr *a,
                return sysfs_emit(buf, "%u\n", sbi->compr_new_inode);
 #endif
 
+       if (!strcmp(a->attr.name, "gc_segment_mode"))
+               return sysfs_emit(buf, "%u\n", sbi->gc_segment_mode);
+
+       if (!strcmp(a->attr.name, "gc_reclaimed_segments")) {
+               return sysfs_emit(buf, "%u\n",
+                       sbi->gc_reclaimed_segs[sbi->gc_segment_mode]);
+       }
+
        ui = (unsigned int *)(ptr + a->offset);
 
        return sprintf(buf, "%u\n", *ui);
@@ -515,6 +523,21 @@ out:
                return count;
        }
 
+       if (!strcmp(a->attr.name, "gc_segment_mode")) {
+               if (t < MAX_GC_MODE)
+                       sbi->gc_segment_mode = t;
+               else
+                       return -EINVAL;
+               return count;
+       }
+
+       if (!strcmp(a->attr.name, "gc_reclaimed_segments")) {
+               if (t != 0)
+                       return -EINVAL;
+               sbi->gc_reclaimed_segs[sbi->gc_segment_mode] = 0;
+               return count;
+       }
+
        *ui = (unsigned int)t;
 
        return count;
@@ -740,6 +763,9 @@ F2FS_RW_ATTR(ATGC_INFO, atgc_management, atgc_candidate_count, max_candidate_cou
 F2FS_RW_ATTR(ATGC_INFO, atgc_management, atgc_age_weight, age_weight);
 F2FS_RW_ATTR(ATGC_INFO, atgc_management, atgc_age_threshold, age_threshold);
 
+F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, gc_segment_mode, gc_segment_mode);
+F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, gc_reclaimed_segments, gc_reclaimed_segs);
+
 #define ATTR_LIST(name) (&f2fs_attr_##name.attr)
 static struct attribute *f2fs_attrs[] = {
        ATTR_LIST(gc_urgent_sleep_time),
@@ -812,6 +838,8 @@ static struct attribute *f2fs_attrs[] = {
        ATTR_LIST(atgc_candidate_count),
        ATTR_LIST(atgc_age_weight),
        ATTR_LIST(atgc_age_threshold),
+       ATTR_LIST(gc_segment_mode),
+       ATTR_LIST(gc_reclaimed_segments),
        NULL,
 };
 ATTRIBUTE_GROUPS(f2fs);