f2fs: introduce reserved_pin_section sysfs entry

[ Upstream commit 59c1c89e9ba8cefff05aa982dd9e6719f25e8ec5 ]

This patch introduces /sys/fs/f2fs/<dev>/reserved_pin_section for tuning
@needed parameter of has_not_enough_free_secs(), if we configure it w/
zero, it can avoid f2fs_gc() as much as possible while fallocating on
pinned file.

Signed-off-by: Chao Yu <chao@kernel.org>
Reviewed-by: wangzijie <wangzijie1@honor.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Stable-dep-of: e462fc48ceb8 ("f2fs: maintain one time GC mode is enabled during whole zoned GC cycle")
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/Documentation/ABI/testing/sysfs-fs-f2fs b/Documentation/ABI/testing/sysfs-fs-f2fs
index 87b32ca7f3a466c2e2df9b3bef8f22418d6d189d..ade7da6352de6c0239e30e9f5e096495dc337b84 100644 (file)
--- a/Documentation/ABI/testing/sysfs-fs-f2fs
+++ b/Documentation/ABI/testing/sysfs-fs-f2fs
@@ -858,3 +858,12 @@ Description:       This is a read-only entry to show the value of sb.s_encoding_flags,
                SB_ENC_STRICT_MODE_FL            0x00000001
                SB_ENC_NO_COMPAT_FALLBACK_FL     0x00000002
                ============================     ==========
+
+What:          /sys/fs/f2fs/<disk>/reserved_pin_section
+Date:          June 2025
+Contact:       "Chao Yu" <chao@kernel.org>
+Description:   This threshold is used to control triggering garbage collection while
+               fallocating on pinned file, so, it can guarantee there is enough free
+               reserved section before preallocating on pinned file.
+               By default, the value is ovp_sections, especially, for zoned ufs, the
+               value is 1.

diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 08bab3de5c50d056a2d465daf01a1772f1714cb5..695f74875b8f1b0b413fc25a30ab0e390d358d0e 100644 (file)
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -1702,6 +1702,9 @@ struct f2fs_sb_info {
        /* for skip statistic */
        unsigned long long skipped_gc_rwsem;            /* FG_GC only */
 
+       /* free sections reserved for pinned file */
+       unsigned int reserved_pin_section;
+
        /* threshold for gc trials on pinned files */
        unsigned short gc_pin_file_threshold;
        struct f2fs_rwsem pin_sem;

diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index be32f672497d64b4ad6b10160a9f35bc25c886e5..67053bf6ca3ec5280fca3022f49627b4ccc8ece8 100644 (file)
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -1850,9 +1850,8 @@ next_alloc:
                        }
                }
 
-               if (has_not_enough_free_secs(sbi, 0, f2fs_sb_has_blkzoned(sbi) ?
-                       ZONED_PIN_SEC_REQUIRED_COUNT :
-                       GET_SEC_FROM_SEG(sbi, overprovision_segments(sbi)))) {
+               if (has_not_enough_free_secs(sbi, 0,
+                               sbi->reserved_pin_section)) {
                        f2fs_down_write(&sbi->gc_lock);
                        stat_inc_gc_call_count(sbi, FOREGROUND);
                        err = f2fs_gc(sbi, &gc_control);

diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
index ee8352246ce477e45d272a182b40da45c79663dd..ae726395440402ee2b21ab39ce6ed4463ae4e8bf 100644 (file)
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -4705,6 +4705,10 @@ try_onemore:
        /* get segno of first zoned block device */
        sbi->first_seq_zone_segno = get_first_seq_zone_segno(sbi);
 
+       sbi->reserved_pin_section = f2fs_sb_has_blkzoned(sbi) ?
+                       ZONED_PIN_SEC_REQUIRED_COUNT :
+                       GET_SEC_FROM_SEG(sbi, overprovision_segments(sbi));
+
        /* Read accumulated write IO statistics if exists */
        seg_i = CURSEG_I(sbi, CURSEG_HOT_NODE);
        if (__exist_node_summaries(sbi))

diff --git a/fs/f2fs/sysfs.c b/fs/f2fs/sysfs.c
index 309b73421dd92e9d684a3055c3b70b528515a0f8..624ce79f08fd2fde4d04bd74752605cfabf127d6 100644 (file)
--- a/fs/f2fs/sysfs.c
+++ b/fs/f2fs/sysfs.c
@@ -847,6 +847,13 @@ out:
                return count;
        }
 
+       if (!strcmp(a->attr.name, "reserved_pin_section")) {
+               if (t > GET_SEC_FROM_SEG(sbi, overprovision_segments(sbi)))
+                       return -EINVAL;
+               *ui = (unsigned int)t;
+               return count;
+       }
+
        *ui = (unsigned int)t;
 
        return count;
@@ -1153,6 +1160,7 @@ F2FS_SBI_GENERAL_RO_ATTR(unusable_blocks_per_sec);
 F2FS_SBI_GENERAL_RW_ATTR(blkzone_alloc_policy);
 #endif
 F2FS_SBI_GENERAL_RW_ATTR(carve_out);
+F2FS_SBI_GENERAL_RW_ATTR(reserved_pin_section);
 
 /* STAT_INFO ATTR */
 #ifdef CONFIG_F2FS_STAT_FS
@@ -1343,6 +1351,7 @@ static struct attribute *f2fs_attrs[] = {
        ATTR_LIST(last_age_weight),
        ATTR_LIST(max_read_extent_count),
        ATTR_LIST(carve_out),
+       ATTR_LIST(reserved_pin_section),
        NULL,
 };
 ATTRIBUTE_GROUPS(f2fs);