This patch introduces /sys/fs/f2fs/<disk>/critical_task_priority, w/ this new sysfs interface, we can tune priority of f2fs_ckpt thread and f2fs_gc thread.
Signed-off-by: Chao Yu <[email protected]> --- Documentation/ABI/testing/sysfs-fs-f2fs | 8 ++++++++ fs/f2fs/checkpoint.c | 2 ++ fs/f2fs/f2fs.h | 4 ++++ fs/f2fs/gc.c | 2 ++ fs/f2fs/super.c | 1 + fs/f2fs/sysfs.c | 17 +++++++++++++++++ 6 files changed, 34 insertions(+) diff --git a/Documentation/ABI/testing/sysfs-fs-f2fs b/Documentation/ABI/testing/sysfs-fs-f2fs index ea6474db8a31..c1d2b3fd9c65 100644 --- a/Documentation/ABI/testing/sysfs-fs-f2fs +++ b/Documentation/ABI/testing/sysfs-fs-f2fs @@ -987,3 +987,11 @@ Contact: "Chao Yu" <[email protected]> Description: f2fs can tune priority of thread which has entered into critical region covered by f2fs rwsemphore lock. This sysfs entry can be used to control priority value, the range is [100,139], by default the value is 120. + +What: /sys/fs/f2fs/<disk>/critical_task_priority +Date: February 2026 +Contact: "Chao Yu" <[email protected]> +Description: It can be used to tune priority of f2fs critical task, e.g. f2fs_ckpt, f2fs_gc + threads, limitation as below: + - it requires user has CAP_SYS_NICE capability. + - the range is [100, 139], by default the value is 100. diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c index 4afa5d9a19fc..6dd39b7de11a 100644 --- a/fs/f2fs/checkpoint.c +++ b/fs/f2fs/checkpoint.c @@ -2158,6 +2158,8 @@ int f2fs_start_ckpt_thread(struct f2fs_sb_info *sbi) } set_task_ioprio(cprc->f2fs_issue_ckpt, cprc->ckpt_thread_ioprio); + set_user_nice(cprc->f2fs_issue_ckpt, + PRIO_TO_NICE(sbi->critical_task_priority)); return 0; } diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h index a6e7368fc40a..aa0bca9f851d 100644 --- a/fs/f2fs/f2fs.h +++ b/fs/f2fs/f2fs.h @@ -1593,6 +1593,7 @@ enum node_type { #define MAX_LOCK_ELAPSED_TIME 500 #define F2FS_DEFAULT_TASK_PRIORITY (DEFAULT_PRIO) +#define F2FS_CRITICAL_TASK_PRIORITY NICE_TO_PRIO(0) static inline int f2fs_test_bit(unsigned int nr, char *addr); static inline void f2fs_set_bit(unsigned int nr, char *addr); @@ -2010,6 +2011,9 @@ struct f2fs_sb_info { /* adjust priority for task which is in critical region covered by lock */ unsigned int lock_duration_priority; + /* priority for critical task, e.g. f2fs_ckpt, f2fs_gc threads */ + long critical_task_priority; + #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 60378614bc54..f46b2673d31f 100644 --- a/fs/f2fs/gc.c +++ b/fs/f2fs/gc.c @@ -234,6 +234,8 @@ int f2fs_start_gc_thread(struct f2fs_sb_info *sbi) return err; } + set_user_nice(gc_th->f2fs_gc_task, + PRIO_TO_NICE(sbi->critical_task_priority)); return 0; } diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c index d5cf7265e5d3..1a755997aff5 100644 --- a/fs/f2fs/super.c +++ b/fs/f2fs/super.c @@ -4340,6 +4340,7 @@ static void init_sb_info(struct f2fs_sb_info *sbi) sbi->max_lock_elapsed_time = MAX_LOCK_ELAPSED_TIME; sbi->adjust_lock_priority = 0; sbi->lock_duration_priority = F2FS_DEFAULT_TASK_PRIORITY; + sbi->critical_task_priority = F2FS_CRITICAL_TASK_PRIORITY; sbi->sum_blocksize = f2fs_sb_has_packed_ssa(sbi) ? 4096 : sbi->blocksize; diff --git a/fs/f2fs/sysfs.c b/fs/f2fs/sysfs.c index 3a272e7edf23..5fbfdc96e502 100644 --- a/fs/f2fs/sysfs.c +++ b/fs/f2fs/sysfs.c @@ -969,6 +969,21 @@ static ssize_t __sbi_store(struct f2fs_attr *a, return count; } + if (!strcmp(a->attr.name, "critical_task_priority")) { + if (t < NICE_TO_PRIO(MIN_NICE) || t > NICE_TO_PRIO(MAX_NICE)) + return -EINVAL; + if (!capable(CAP_SYS_NICE)) + return -EPERM; + sbi->critical_task_priority = t; + if (sbi->cprc_info.f2fs_issue_ckpt) + set_user_nice(sbi->cprc_info.f2fs_issue_ckpt, + PRIO_TO_NICE(sbi->critical_task_priority)); + if (sbi->gc_thread && sbi->gc_thread->f2fs_gc_task) + set_user_nice(sbi->gc_thread->f2fs_gc_task, + PRIO_TO_NICE(sbi->critical_task_priority)); + return count; + } + __sbi_store_value(a, sbi, ptr + a->offset, t); return count; @@ -1288,6 +1303,7 @@ F2FS_SBI_GENERAL_RW_ATTR(bggc_io_aware); F2FS_SBI_GENERAL_RW_ATTR(max_lock_elapsed_time); F2FS_SBI_GENERAL_RW_ATTR(lock_duration_priority); F2FS_SBI_GENERAL_RW_ATTR(adjust_lock_priority); +F2FS_SBI_GENERAL_RW_ATTR(critical_task_priority); /* STAT_INFO ATTR */ #ifdef CONFIG_F2FS_STAT_FS @@ -1496,6 +1512,7 @@ static struct attribute *f2fs_attrs[] = { ATTR_LIST(max_lock_elapsed_time), ATTR_LIST(lock_duration_priority), ATTR_LIST(adjust_lock_priority), + ATTR_LIST(critical_task_priority), NULL, }; ATTRIBUTE_GROUPS(f2fs); -- 2.40.1 _______________________________________________ Linux-f2fs-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel
