[PATCH v2] ext4: add sysfs attribute err_report_sec to control s_err_report timer

Baolin Liu
2025-12-11T03:05:36Z

From: Baolin Liu <liubaolin@kylinos.cn>

Add a new sysfs attribute "err_report_sec" to control the s_err_report
timer in ext4_sb_info. Writing '0' disables the timer, while writing
a non-zero value enables the timer and sets the timeout in seconds.

Signed-off-by: Baolin Liu <liubaolin@kylinos.cn>
---
Note:
v2:
- Restore the original timer_setup() call location to address
- the ‘WARNING: ODEBUG bug in ext4_update_super’ reported in v1.
---
fs/ext4/ext4.h | 4 +++-
fs/ext4/super.c | 27 ++++++++++++++++++---------
fs/ext4/sysfs.c | 36 ++++++++++++++++++++++++++++++++++++
3 files changed, 57 insertions(+), 10 deletions(-)

diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index 57087da6c7be..9eb5bf2a237a 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -1673,6 +1673,8 @@ struct ext4_sb_info {

/* timer for periodic error stats printing */
struct timer_list s_err_report;
+ /* timeout in seconds for s_err_report; 0 disables the timer. */
+ unsigned long s_err_report_sec;

/* Lazy inode table initialization info */
struct ext4_li_request *s_li_request;
@@ -2349,7 +2351,6 @@ static inline int ext4_emergency_state(struct super_block *sb)
#define EXT4_DEF_SB_UPDATE_INTERVAL_SEC (3600) /* seconds (1 hour) */
#define EXT4_DEF_SB_UPDATE_INTERVAL_KB (16384) /* kilobytes (16MB) */

-
/*
* Minimum number of groups in a flexgroup before we separate out
* directories into the first block group of a flexgroup
@@ -3187,6 +3188,7 @@ extern void ext4_mark_group_bitmap_corrupted(struct super_block *sb,
unsigned int flags);
extern unsigned int ext4_num_base_meta_blocks(struct super_block *sb,
ext4_group_t block_group);
+extern void print_daily_error_info(struct timer_list *t);

extern __printf(7, 8)
void __ext4_error(struct super_block *, const char *, unsigned int, bool,
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 33e7c08c9529..24ffda1a0dca 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -3635,10 +3635,12 @@ int ext4_feature_set_ok(struct super_block *sb, int readonly)
}

/*
- * This function is called once a day if we have errors logged
- * on the file system
+ * This function is called once a day by default if we have errors logged
+ * on the file system.
+ * Use the err_report_sec sysfs attribute to disable or adjust its call
+ * freequency.
*/
-static void print_daily_error_info(struct timer_list *t)
+void print_daily_error_info(struct timer_list *t)
{
struct ext4_sb_info *sbi = timer_container_of(sbi, t, s_err_report);
struct super_block *sb = sbi->s_sb;
@@ -3678,7 +3680,9 @@ static void print_daily_error_info(struct timer_list *t)
le64_to_cpu(es->s_last_error_block));
printk(KERN_CONT "\n");
}
- mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ); /* Once a day */
+
+ if (sbi->s_err_report_sec)
+ mod_timer(&sbi->s_err_report, jiffies + secs_to_jiffies(sbi->s_err_report_sec));
}

/* Find next suitable group and run ext4_init_inode_table */
@@ -5637,8 +5641,12 @@ static int __ext4_fill_super(struct fs_context *fc, struct super_block *sb)
clear_opt(sb, DISCARD);
}

- if (es->s_error_count)
- mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */
+ if (es->s_error_count) {
+ sbi->s_err_report_sec = 5*60; /* first time 5 minutes */
+ mod_timer(&sbi->s_err_report,
+ jiffies + secs_to_jiffies(sbi->s_err_report_sec));
+ }
+ sbi->s_err_report_sec = 24*60*60; /* Once a day */

/* Enable message ratelimiting. Default is 10 messages per 5 secs. */
ratelimit_state_init(&sbi->s_err_ratelimit_state, 5 * HZ, 10);
@@ -6184,10 +6192,11 @@ static void ext4_update_super(struct super_block *sb)
ext4_errno_to_code(sbi->s_last_error_code);
/*
* Start the daily error reporting function if it hasn't been
- * started already
+ * started already and sbi->s_err_report_sec is not zero
*/
- if (!es->s_error_count)
- mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);
+ if (!es->s_error_count && !sbi->s_err_report_sec)
+ mod_timer(&sbi->s_err_report,
+ jiffies + secs_to_jiffies(sbi->s_err_report_sec));
le32_add_cpu(&es->s_error_count, sbi->s_add_error_count);
sbi->s_add_error_count = 0;
}
diff --git a/fs/ext4/sysfs.c b/fs/ext4/sysfs.c
index 987bd00f916a..ce9c18f6ba26 100644
--- a/fs/ext4/sysfs.c
+++ b/fs/ext4/sysfs.c
@@ -40,6 +40,7 @@ typedef enum {
attr_pointer_string,
attr_pointer_atomic,
attr_journal_task,
+ attr_err_report_sec,
} attr_id_t;

typedef enum {
@@ -130,6 +131,36 @@ static ssize_t trigger_test_error(struct ext4_sb_info *sbi,
return count;
}

+static ssize_t err_report_sec_store(struct ext4_sb_info *sbi,
+ const char *buf, size_t count)
+{
+ unsigned long t;
+ int ret;
+
+ ret = kstrtoul(skip_spaces(buf), 0, &t);
+ if (ret)
+ return ret;
+
+ /*the maximum time interval must not exceed one year.*/
+ if (t > (365*24*60*60))
+ return -EINVAL;
+
+ if (sbi->s_err_report_sec == t) /*nothing to do*/
+ goto out;
+ else if (!sbi->s_err_report_sec && t) {
+ timer_setup(&sbi->s_err_report, print_daily_error_info, 0);
+ } else if (sbi->s_err_report_sec && !t) {
+ timer_delete_sync(&sbi->s_err_report);
+ goto out;
+ }
+
+ sbi->s_err_report_sec = t;
+ mod_timer(&sbi->s_err_report, jiffies + secs_to_jiffies(sbi->s_err_report_sec));
+
+out:
+ return count;
+}
+
static ssize_t journal_task_show(struct ext4_sb_info *sbi, char *buf)
{
if (!sbi->s_journal)
@@ -217,6 +248,7 @@ EXT4_ATTR_OFFSET(mb_group_prealloc, 0644, clusters_in_group,
ext4_sb_info, s_mb_group_prealloc);
EXT4_ATTR_OFFSET(mb_best_avail_max_trim_order, 0644, mb_order,
ext4_sb_info, s_mb_best_avail_max_trim_order);
+EXT4_ATTR_OFFSET(err_report_sec, 0644, err_report_sec, ext4_sb_info, s_err_report_sec);
EXT4_RW_ATTR_SBI_UI(inode_goal, s_inode_goal);
EXT4_RW_ATTR_SBI_UI(mb_stats, s_mb_stats);
EXT4_RW_ATTR_SBI_UI(mb_max_to_scan, s_mb_max_to_scan);
@@ -309,6 +341,7 @@ static struct attribute *ext4_attrs[] = {
ATTR_LIST(last_trim_minblks),
ATTR_LIST(sb_update_sec),
ATTR_LIST(sb_update_kb),
+ ATTR_LIST(err_report_sec),
NULL,
};
ATTRIBUTE_GROUPS(ext4);
@@ -396,6 +429,7 @@ static ssize_t ext4_generic_attr_show(struct ext4_attr *a,
return sysfs_emit(buf, "%u\n", le32_to_cpup(ptr));
return sysfs_emit(buf, "%u\n", *((unsigned int *) ptr));
case attr_pointer_ul:
+ case attr_err_report_sec:
return sysfs_emit(buf, "%lu\n", *((unsigned long *) ptr));
case attr_pointer_u8:
return sysfs_emit(buf, "%u\n", *((unsigned char *) ptr));
@@ -519,6 +553,8 @@ static ssize_t ext4_attr_store(struct kobject *kobj,
return inode_readahead_blks_store(sbi, buf, len);
case attr_trigger_test_error:
return trigger_test_error(sbi, buf, len);
+ case attr_err_report_sec:
+ return err_report_sec_store(sbi, buf, len);
default:
return ext4_generic_attr_store(a, sbi, buf, len);
}
--
2.39.2